CN121753136A

CN121753136A - Methods for manufacturing porous electrodes and batteries containing such electrodes

Info

Publication number: CN121753136A
Application number: CN202480055204.7A
Authority: CN
Inventors: 法比安·加邦; 伊恩·凯尔富克; 洛尔·吉罗内; 阿德南·萨伊格; 洛里斯·德绍; 迈赫迪·布马赫拉兹
Original assignee: I Ten Corp
Current assignee: I Ten Corp
Priority date: 2023-06-28
Filing date: 2024-06-27
Publication date: 2026-03-27
Also published as: EP4736244A1; TW202510381A; KR20260030129A; FR3150644B1; IL325651A; WO2025003357A1; FR3150644A1

Abstract

This invention relates to a porous electrode that can be used in energy storage devices or energy generation devices (e.g., lithium-ion batteries). The porous electrode is a porous layer comprising at least one electrode active material P and an oxide electronic conductor material.

Description

Method for manufacturing porous electrode and battery containing such electrode

Technical Field

The present invention relates to an energy storage device or an energy production device. More precisely, the invention relates to electrodes, such as capacitors, photovoltaic cells or ion intercalation cells, in particular lithium ion, sodium ion and potassium ion cells, which can be used in energy storage or production devices. The invention is applicable to negative and positive electrodes. It relates to porous electrodes that can be impregnated with an ion conducting phase (e.g., a solid electrolyte without a liquid phase or a liquid electrolyte).

The invention also relates to a method for producing such a porous electrode using an aggregate or agglomerate of nanoparticles of an electrode material and at least one oxide electron conductor material precursor, and to the electrode thus obtained. The invention also relates to a method for manufacturing an energy storage or generation device, in particular to a method for manufacturing a lithium ion battery comprising at least one of these electrodes, and the battery thus obtained.

Background

Among the various commercial electrochemical storage technologies, the energy density of lithium ion batteries is optimal. Electrodes of various structures and chemical compositions can be used to produce these cells. Methods for producing lithium Ion Batteries are presented in a number of articles and patents, reviewed in the 2002 publication (Kluever Academic/Plenum Press) entitled "ADVANCES IN lithium-Ion Batteries" (w. Van Schalkwijk and b. Scissati).

There is an increasing need for very small-sized rechargeable batteries that can be integrated on electronic circuit boards that can be used in many fields, such as cards for secure transactions, electronic tags, implantable medical devices, and in various micromechanical systems.

There is also an increasing demand for large capacity rechargeable batteries, in particular for powering transportation devices (electric bicycles, scooters, electric motorcycles, electric vehicles, electric commercial vehicles) and for storing electric energy, for example for storing electric power generated by intermittent power generation devices (wind turbines, photovoltaic panels) or for stabilizing electric grids affected by highly fluctuating supplies and demands.

There is also an increasing demand for medium-sized rechargeable batteries for various automatic and portable devices, such as mobile phones, portable computers, portable electric tools, and kitchen appliances for intermittent use.

In all these applications, the possibility of fast recharging of the battery is a very popular feature. Also, these cells have to be at risk of thermal runaway. Finally, it is desirable that they can operate over a wide temperature range.

According to the prior art, the electrodes of lithium ion batteries can be produced by means of a coating technique, in particular by means of coating. These methods make it possible to deposit on the surface of the substrate an ink composed of active material particles in powder form, the particles constituting such powder having an average particle size generally ranging from 5 μm to 15 μm in diameter.

These deposition techniques, in particular by coating, make it possible to produce layers having a thickness of about 20 μm to about 400 μm. The power and energy of the cell can be regulated by adjusting the thickness and porosity of the layers, the size of the active particles that make up the layers, and the presence of various components in the layers, such as binders or electronic conductor materials. In order to produce a microcell, it is desirable that each layer constituting the microcell have a relatively thin thickness.

In addition to the problems associated with ink formulations in order to obtain high performance electrodes at low production costs, it must be remembered that the ratio between the energy density and the power density of the electrode can be adjusted as a function of the active material particle size and indirectly as a function of the specific surface area of the electrode layer and its thickness. J. Newman's article （"Optimization of Porosityand Thickness of a Battery Electrode by Means of A Reaction-Zone Model", J.Electrochem. Soc.,142(1),, pages 97-101 (1995)) shows the respective effect of electrode thickness and its porosity on its discharge state (power) and energy density.

The binder-free mesoporous electrode layer for lithium ion batteries may be deposited by electrophoresis, as is known from WO2019/215407 (I-TEN). They can be impregnated with liquid electrolytes, but their resistivity is still quite high.

In order to increase the low electron conductivity of electrodes, particularly when these electrodes have a high thickness or are made of an electrode active material having low electron conductivity, a certain amount of an electron conductor material, such as carbon black, is generally added to the electrode active material particles. Ideally, the electron conductor particles should be available at any point on the surface of the electrode active material particles so as to be capable of simultaneous intercalation/deintercalation over the entire surface of the electrode active particles, thereby maximizing current density and minimizing stress and localized heating due to non-uniform electrical transport.

In practice, it is difficult to control the distribution of carbon black in the electrode. Furthermore, these problems become more prevalent as smaller and smaller active material particles are increasingly used. The uneven distribution of carbon black in the electrode results in a much higher polarization of the electrode, which results in an increase in the series resistance of a battery comprising such an electrode. The higher the current density, the more pronounced will be the imbalance of these local charge states. These imbalances thus lead to loss of cycle performance, safety risks, and power limitations of the battery cells (battery cells). The same is true when the electrode has a non-uniform porosity, i.e. a size distribution, which non-uniformity makes wetting of the electrode pores more difficult.

Under such circumstances, in order to reduce the resistivity of the electrode, the applicant has developed a mesoporous electrode comprising a mesoporous layer of at least one electrode active material, having a carbon coating on and within the pores of the mesoporous layer, as is known from WO2021/220174 (I-TEN). The presence of such carbon electron conductor coatings on the electrodes makes it possible to reduce their resistivity, but does not significantly increase their voltage, temperature and electrochemical stability. Furthermore, the production of carbon electronic conductor coatings on electrodes is costly and difficult to implement.

With the increasing demand for ultra-small-sized rechargeable batteries, the electrodes must meet increasingly stringent specifications. They must have high chemical and electrochemical stability, robustness and corrosion resistance in order for the batteries containing them to have high cycle performance, storage stability, temperature stability and long-term reliability in combination with high energy density and high power density. The present invention seeks to overcome at least some of the disadvantages of the prior art described above.

More precisely, the technical problem sought to be solved by the present invention is to provide a method for manufacturing a porous electrode having a high and uniform electronic conductivity and a controllable pore density, which is simple, safe, fast, easy to implement and low in cost.

The invention also aims to propose a safe porous electrode with high electronic conductivity, stable mechanical structure, good thermal stability (especially at high temperatures) and long service life, and whatever the thickness of the electrode.

Another object of the invention is to propose an electrode for a battery capable of operating at high temperatures without reliability problems and without risk of fire.

It is a further object of the present invention to provide a porous electrode which, in addition to the above features, can be readily wetted and impregnated by ionic liquids or polymers.

It is a further object of the present invention to provide a method for producing an energy storage device or an energy production device (e.g. a capacitor, supercapacitor, hybrid supercapacitor, photocell, photochemical cell or cell, in particular a lithium ion cell, sodium ion cell or even a potassium ion cell) comprising a porous electrode according to the present invention.

It is a further object of the present invention to provide an energy storage device or energy production device (e.g. battery, in particular lithium ion battery and micro-battery, capacitor, supercapacitor, hybrid supercapacitor, such as lithium ion hybrid supercapacitor, hereinafter abbreviated to LiC, sodium ion hybrid supercapacitor, hereinafter abbreviated to SIHC, potassium ion hybrid supercapacitor, hereinafter abbreviated to PIHC) capable of storing high energy density, recovering the energy at very high power density (in particular in capacitor or supercapacitor), withstanding high temperatures, having excellent cycle life, and increased safety.

Disclosure of Invention

In order to improve the performance of electrodes that can be used in energy storage devices or energy production devices, in particular in conventional lithium ion batteries, in particular by reducing their resistivity, while at the same time significantly improving their voltage, temperature and electrochemical stability, the inventors have sought to find alternatives to the carbon electronic conductor coatings proposed in application WO2021/220174 (I-TEN).

According to the invention, this problem is solved by an electrode for a lithium, sodium or potassium ion battery, which is completely ceramic, porous, free of organic binders and has a porosity of 25 to 60% by volume. The electrode according to the invention is a porous, preferably mesoporous, layer comprising at least one electrode active material and an oxide electron conductor material, the porosity of which is 25 to 60% by volume. Advantageously, the electrode according to the invention comprises a region of electrode active material P covered at least partially with a coating of oxide electron conductor material over the whole internal volume and surface of the electrode, preferably the electrode according to the invention comprises a region of electrode active material P covered with a coating of oxide electron conductor material over the whole internal volume and surface of the electrode.

Such a completely solid, porous, preferably mesoporous, layer free of organic components is obtained from agglomerates and/or aggregates of primary nanoparticles of at least one electrode active material and at least one oxide electron conductor material precursor. The primary particles constituting these agglomerates and/or aggregates are of a size of a nanometer order or several tens of nanometers, and the agglomerates and/or aggregates contain at least four primary particles.

The substrate may be a substrate capable of acting as an electrical sub-fluid in the first embodiment or a temporary intermediate substrate in the second embodiment, as will be explained in more detail below.

The fact that agglomerates of tens or even hundreds of nanometers in diameter are used instead of non-agglomerated primary particles (each particle having a size of the order of a few nanometers or tens of nanometers) enables the thickness of the deposit to be increased. However, the agglomerates must be kept small in order to be able to form a continuous mesoporous film during the heat treatment of the layer. If the agglomerates are too large, this will prevent them from sintering and two different types of voids are observed to form in the layer, voids between the agglomerates and voids inside the agglomerates.

After sintering, a porous, preferably mesoporous, layer or plate is obtained that is free of carbon black or organic binders, wherein all primary nanoparticles are joined (by necking, or other known) together to form a continuous mesoporous network characterized by a unimodal porosity. The porous layer, preferably the mesoporous layer, thus obtained is entirely solid and ceramic. During cycling there is no longer any risk of losing electrical contact between the active material particles, which improves the cycling performance of the battery. Furthermore, after sintering, the porous, preferably mesoporous, layer perfectly adheres to the metal substrate on which the deposition or transfer (in the case of initial deposition on the intermediate substrate) is carried out.

The heat treatment is performed at high temperature to sinter the nanoparticles together so that the electrode can be completely dried and any trace amounts of water or solvents or other organic additives (stabilizers, binders) adsorbed on the surface of the active material particles are eliminated. The low temperature heat treatment (sintering) may be preceded by a low temperature heat treatment (debonding) to dry the placed or deposited electrode and remove traces of water or solvents or other organic additives (stabilizers, binders) adsorbed on the surface of the active material particles, which debonding may be performed in an oxidizing atmosphere.

The porosity of the final electrode can be adjusted according to the sintering time and temperature. The porosity can be adjusted in the range of 25% to 60% depending on the energy density requirements.

In all cases, the power density of the electrodes thus obtained remains extremely high, due to the porosity, preferably due to the mesoporous nature. Furthermore, the dynamic balance of the cell remains perfect, regardless of the size of the pores in the active material (the concept of nanoparticles after sintering is known to be no longer applicable to materials with a three-dimensional structure of channels and mesoporous networks), which helps to maximize the power density and the service life of the cell.

The electrode according to the present invention has a high specific surface area, which reduces the ionic resistance of the electrode. However, in order for the electrode to provide maximum power, it must also have very good electron conductivity to prevent ohmic losses in the cell. The greater the electrode thickness, the more critical the improvement in the electrical conductivity of the cell. Furthermore, this electron conductivity must be completely uniform throughout the electrode to prevent localized having large resistive areas, which may lead to hot spots forming during power operation of the cell.

According to an essential feature of the invention, the electrode according to the invention comprises at least one electrode active material and an oxide electron conductor material, preferably a region of electrode active material P covered at least partially with a coating of oxide electron conductor material over the whole internal volume and surface of the electrode, preferably a region of electrode active material P covered with a coating of oxide electron conductor material in a perfectly distributed manner over the whole internal volume and surface of the electrode.

The coating of the oxide electron conductor material according to the invention is advantageously SnO ₂, aluminum-doped ZnO (ZnO: al, preferably with a Zn: al of 1:0.015 to 1:0.05), moO ₃、SrMoO₃、In₂O₃、Ga₂O₃ or indium tin oxide.

The thickness of the oxide electron conductor material coating of the entire electrode interior volume is advantageously less than 10nm a, preferably less than 7a nm a, preferably less than 5a nm a, more preferably from 5a nm a to 3a nm a, still more preferably less than 3a nm a. The oxide electron conductor material may be produced from at least one precursor of the oxide electron conductor material, in particular from at least one liquid precursor of the oxide electron conductor material.

The thickness is measured by any suitable technique, in particular by transmission electron microscopy.

More particularly, as mentioned above, the method according to the invention must comprise the step of forming a layer from agglomerated nanoparticles of electrode material (active material) and at least one precursor of oxide electron conductor material, resulting in the nanoparticles being "bonded" together naturally, resulting in a porous rigid three-dimensional structure after consolidation, such as annealing, without the need for organic binders, such porous layers, preferably mesoporous layers being well suited for surface treatment by gaseous or liquid means, or by impregnation into the depth of the open porous structure of the layer.

A first object of the present invention is a method for producing a porous electrode, in particular for an electrical energy storage device or an electrical energy production device (e.g. a battery), said electrode being a porous layer comprising at least one electrode active material P and an oxide electron conductor material deposited on a substrate, said electrode being binder-free, having a porosity of 25 to 60% by volume, preferably 25 to 50% by volume, and pores with an average diameter of less than 100 nm, said production method being characterized in that it comprises:

(a) Providing a substrate, at least one oxide electron conductor material precursor and a colloidal suspension or paste comprising aggregates or agglomerates of primary nanoparticles of at least one electrode active material P, the primary nanoparticles having an average primary diameter D ₅₀ of from 2 nm to 400 nm, preferably from 2 nm to 100 nm, more preferably from 2 nm to 60 nm, the aggregates or agglomerates having an average diameter D ₅₀ of from 50 nm to 900 nm, preferably from 100 nm to 800 nm, it being understood that the substrate may be a substrate capable of functioning as an electrical subset fluid, or an intermediate substrate,

(B) Mixing one or more oxide electron conductor material precursors provided in step (a) with the colloidal suspension or paste comprising aggregates or agglomerates of primary nanoparticles of at least one electrode active material P to form a mixture,

(C) Forming a layer from the mixture obtained at the end of step (b) by a method selected from the group consisting of electrophoresis, additive manufacturing methods, printing methods, preferably inkjet printing or flexographic printing, coating methods, preferably knife coating, roll coating, curtain coating, dip coating or slot die coating.

(D) Drying the layer obtained in step (c) so as to obtain a dried layer, which is separated from its intermediate substrate, if necessary, after drying step (d),

(E) Converting one or more oxide electron conductor material precursors to an oxide electron conductor material, such that the dried layer comprises the oxide electron conductor material,

(F) Curing the layer by heat treatment and/or mechanical treatment, preferably by sintering, to obtain a porous electrode, preferably a mesoporous electrode,

It will be appreciated that steps (e) and (f) may be performed in the same heat treatment process.

The method according to the invention may comprise, in step (e), in step (f) or between steps (e) and (f), subjecting the dried layer to a heat treatment, preferably in an oxidizing atmosphere.

Advantageously, after step (f), the pores of the porous electrode are impregnated with electrolyte. The electrolyte may include lithium, potassium or sodium salts, depending on the type of battery desired. The electrolyte is preferably a phase carrying lithium, sodium or potassium ions selected from the group consisting of:

electrolyte consisting of at least one aprotic solvent and at least one lithium, sodium or potassium salt;

electrolyte consisting of at least one ionic liquid and at least one lithium, sodium or potassium salt;

A mixture of at least one aprotic solvent and at least one ionic liquid and at least one lithium, sodium or potassium salt;

Ionic liquid polymer;

a polymer ion conductor made by adding at least one lithium, sodium or potassium salt, and

By adding a liquid electrolyte to the polymer phase or porous structure of the porous electrode, or a polymer ion conductor made of an ion conductor polymer,

The ion conductor polymer is preferably selected from the group consisting of polyethylene oxide (PEO), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), poly (propylene carbonate) (PPC), poly (carbonate) (PEC), poly (ethylene carbonate) (PVC), polyvinylidene fluoride (PVDF), polypropylene glycol (PPG), poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polydimethylsiloxane (PDMS), poly (epsilon-caprolactone) (PCL) and poly (trimethylene carbonate) (PTMC).

The phase carrying lithium ions may comprise a mixture of ionic liquids. Advantageously, the ionic liquid may be a cation of the type 1-ethyl-3-methylimidazolium (also known as emi+) and/or n-propyl-n-methylpyrrolidinium (also known as PYR ₁₃ ⁺) and/or n-butyl-n-methylpyrrolidinium (also known as PYR ₁₄ ⁺) combined with an anion of the type bis (trifluoromethylsulfonyl) imide (TFSI ^-) and/or bis (fluorosulfonyl) imide (FSI ^-). To form the electrolyte, a lithium salt such as LiTFSI may be dissolved in an ionic liquid as a solvent or in a solvent such as γ -butyrolactone. Gamma-butyrolactone prevents crystallization of ionic liquids, providing a greater working temperature range, especially at low temperatures. The phase carrying sodium or potassium ions may comprise a mixture of ionic liquids. The ionic liquid may be as described above. To form the electrolyte, sodium salts such as naffsi may be used in place of LiTFSI in sodium ion batteries or potassium salts such as KTFSI may be used in place of LiTFSI in potassium ion batteries. The phase carrying lithium, sodium or potassium ions may comprise an ionic liquid polymer, such as poly (1-vinyl-3-alkyl-imidazole) or poly (1-vinyl-N-alkyl-pyrrolidine).

In step (c), a layer may be formed on one or both sides of the substrate.

Advantageously, when the substrate is an intermediate substrate, after drying the layer, in particular after consolidation, the layer of the intermediate substrate is separated in step (d) to form a porous plate.

Advantageously, when the substrate is an intermediate substrate, after step (f), an electronically conductive sheet is provided, which sheet is covered on at least one face, respectively on both faces thereof, with a film of conductive adhesive, and then at least one porous plate is bonded to one face, preferably on each face, of the electronically conductive sheet to obtain a porous, preferably mesoporous, plate or layer on the substrate capable of acting as an electronic sub-fluid. In the present application, the terms "porous layer" and "porous plate" are interchangeable.

Advantageously, step (b) is performed by contacting the colloidal suspension or paste provided in step (a) comprising aggregates or agglomerates of primary nanoparticles of at least one electrode active material P with a liquid phase comprising at least one precursor of said oxide electron conductor material, and wherein the conversion of said one or more oxide electron conductor material precursors into oxide electron conductor material during step (e) is performed by a heat treatment, such as calcination, preferably in air or an oxidizing atmosphere.

Advantageously, the one or more oxide electron conductor material precursors are selected from organic salts containing one or more metal elements capable of forming an oxide electron conductor after a heat treatment such as calcination, and the conversion to an electron conductor material is a heat treatment such as calcination, preferably in air or an oxidizing atmosphere.

These organic salts are preferably selected from:

Alkoxides of at least one metal element capable of forming an oxide electron conductor after a heat treatment, such as calcination, preferably carried out in air or an oxidizing atmosphere,

Nitrate salts of at least one metallic element capable of forming an oxide electron conductor after a heat treatment, such as calcination, preferably carried out in air or an oxidizing atmosphere,

Oxalate of at least one metallic element capable of forming an oxide electronic conductor after a heat treatment, such as calcination, preferably carried out in air or an oxidizing atmosphere, and

Acetate of at least one metal element capable of forming an oxide electron conductor after a heat treatment, such as calcination, preferably carried out in air or an oxidizing atmosphere,

And/or preferably the metal element is selected from tin, zinc, indium, gallium, molybdenum or a mixture of two or three or four or five of these elements.

The metal element may include at least one doping element.

Advantageously, the porous layer obtained at the end of step (f) has a specific surface area of from 10m ²/g to 500m ²/g and/or a thickness of from 2 μm to 400 μm, preferably from 2 μm to 300 μm, more preferably from 3 μm to 200 μm.

Advantageously, when the substrate is a substrate capable of functioning as an electrical sub-fluid, said porous layer obtained at the end of step (f) has a specific surface area of 10m ²/g to 500m ²/g and/or a thickness of 2 μm to 20 μm.

Advantageously, when the substrate is an intermediate substrate, the porous layer obtained at the end of step (f) has a specific surface area of 10m ²/g to 500m ²/g and/or a thickness of 25 μm to 500 μm, preferably 50 μm to 400 μm.

Advantageously, when the colloidal suspension or paste provided in step (a) contains organic additives, such as ligands, stabilizers, binders or residual organic solvents, the dried layer or the porous plate obtained at the end of step (d) is subjected to a heat treatment, preferably in an oxidizing atmosphere, it being understood that this heat treatment and steps (e) and/or (f) may be carried out in the same heat treatment step.

Advantageously, the electrode active material P is selected from the group (a) formed by:

The oxide LiMn ₂O₄、Li_1+xMn_2-xO₄, wherein 0 <x< 0.15,LiCoO₂、LiNiO₂、LiMn_1.5Ni_0.5O₄、LiMn_1.5Ni_0.5-xX_xO₄, wherein X is selected from Al, fe, cr, co, rh, nd, other rare earth elements such as Sc, Y, lu, la, ce, pr, pm, sm, eu, gd, tb, dy, ho, er, tm, yb, and wherein 0 < X < 0.1, liMn _2-xM_xO₄, wherein m= Er, dy, gd, tb, yb, al, Y, ni, co, ti, sn, as, mg, or a mixture of these elements, and wherein 0 < x < 0.4,LiFeO₂、LiMn_1/ ₃Ni_1/3Co_1/3O₂、LiNi_0.8Co_0.15Al_0.05O₂、LiAl_xMn_2-xO₄, wherein 0 ≤ x < 0.15,LiNi_1/xCo_1/yMn_1/zO₂, wherein x+y+z=10;

Li _xM_yO₂, wherein 0.6≤y≤0.85, 0≤x+y≤2, and M is selected from Al, ti, cr, mn, fe, co, ni, cu, zn, zr, nb, mo, ru, sn and Sb, or mixtures of these elements, li _1.20Nb_0.20Mn_0.60O₂;

Li _1+xNb_yMe_zA_pO₂, wherein Me is at least one transition metal selected from Sc, ti, V, cr, mn, fe, co, ni, cu, zn, Y, zr, nb, mo, tc, ru, rh, pd, ag, cd, hf, ta, W, re, os, ir, pt, au, hg, and wherein 0.6< x <1, 0< y <0.5, 0.25≤z <1, wherein A. Noteq. Me and A. Noteq. Nb, and 0≤p≤0.2;

li _xNb_y-aN_aM_z-bP_bO_2-cF_c, wherein 1.2< x≤1.75, 0≤y <0.55, 0.1< z <1, 0≤a <0.5, 0≤b <1, 0≤c <0.8, and wherein M, N and P are each at least one element selected from the group consisting of Ti, ta, V, cr, mn, fe, co, ni, cu, zn, al, zr, Y, mo, ru, rh, ce and Sb;

○ Li_1.25Nb_0.25Mn_0.50O₂;Li_1.3Nb_0.3Mn_0.40O₂;Li_1.3Nb_0.3Fe_0.40O₂;Li_1.3Nb_0.43Ni_0.27O₂;Li_1.3Nb_0.43Co_0.27O₂;Li_1.4Nb_0.2Mn_0.53O₂;

Li _xNi_0.2Mn_0.6O_y, wherein 0.00≤x≤1.52, 1.07≤y <2.4, li _1.2Ni_0.2Mn_0.6O₂;

LiNi _xCo_yMn_1-x-yO₂, wherein 0≤x and y≤0.5, liNi _xCe_zCo_yMn_1-x-yO₂, wherein 0≤x and y≤0.5 and 0≤z;

Phosphate LiFePO₄、LiMnPO₄、LiCoPO₄、LiNiPO₄、Li₃V₂(PO₄)₃、Li₂MPO₄F, wherein m=fe, co, ni or a mixture of these different elements, liMPO ₄ F wherein m=v, fe, T or a mixture of these different elements, phosphate of formula Li MM ' PO ₄ wherein M and M ' (m+.m ') are selected from Fe, mn, ni, co, V, such as LiFe _xCo_1-xPO₄, and wherein 0 < x < 1;

Fe _0.9Co_0.1OF;FeF₃;LiMSO₄ F, where m= Fe, co, ni, mn, zn, mg;

Titanium oxysulfide (TiO _yS_z, where z=2-y and 0.3≤y≤1), tungsten oxysulfide (WO _yS_z, where 0.6< y <3 and 0.1< z < 2), cuS ₂,Li_xV₂O₅, where 0 < x≤2, li _xV₃O₈, where 0 < x≤1.7, li _xTiS₂, where 0 < x≤1, lithium titanium oxysulfide Li _xTiO_yS_z, where z=2-y, 0.3≤y≤1 and 0 < x≤1, li _xWO_yS_z, where z=2-y, 0.3≤y≤1 and 0 < x≤1, li _x CuS, where 0 < x≤1, li _xCuS₂, where 0 < x≤1;

or from the group (B) formed by:

-a transition metal oxide:

Na _xMO_2+z, wherein M is selected from Mg, ca, li, mn, ni, co, cr, sc, te, wherein z≤0.3 and 0< x≤1, preferably 0< x <0.44 or 0.44≤x≤0.67 or 0.67< x≤1;

Na _xM_u/2M'_v/2O_2+z where u+v=2 and M, M' is selected from Mg, ca, li, mn, ni, co, cr, sc, te, where z is equal to or less than 0.3 and 0< x is equal to or less than 1, preferably 0< x is equal to or less than 0.44 or 0.44 is equal to or less than 0.67 or 0.67 is equal to or less than 1;

Na _xM_u/3M'_v/3M''_w/3O_2+z wherein u+v+w=3 and M, M', M "is selected from Mg, ca, li, mn, ni, co, cr, sc, te, wherein z is equal to or less than 0.3 and 0< x is equal to or less than 1, preferably 0< x is equal to or less than 0.44 or 0.44 < x is equal to or less than 0.67 or 0.67< x is equal to or less than 1;

The first step is Na _xMn_yNi_zFe_0.1Mg_0.1O₂, wherein x is more than or equal to 0.67 and less than or equal to 1.0, and x is more than or equal to 0.5 and less than or equal to 1.0 y is less than or equal to 0.7 and 0.1 z is more than or equal to 0.3;

prussian blue and/or Prussian blue analogues, abbreviated as PBA:

Na _xM¹[M²'(CN)₆]_y.nH₂O,M¹ is a transition metal or transition metal alloy, M ²' is a transition metal, the transition metal and transition metal alloy being selected from the group consisting of Fe, ni, co and Mn, wherein 0≤x≤ 2;y≤1 and 0≤n≤12;

-a polyanionic compound:

Na _xM₂(XO₄)₃, wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W, e.g. Na ₃V₂(PO₄)₃;

na _xM₃(XO₄)₂(X₂O₇), wherein 0< X is less than or equal to 4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

na _xM(X₂O₇), wherein 0< X is less than or equal to 4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

Na _xM₂(XO₄)₂F₃, wherein 0< X is less than or equal to 4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

na _xM₂(XO₄)₂F_3-yO_y, wherein 0< X is 4 or less, m= V, fe, cr, mn, co, ni or Sc and 0.07 y is 0.12 or less and x= P, S, as, si, mo or W;

Na _xM₂O₂(XO₄)₂ F, wherein 0< X is less than or equal to 4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

na _xMXO₄, wherein 0< X is less than or equal to 4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

Or from the group (C) formed by:

-a transition metal oxide:

k _xMO_2+z, wherein M is selected from Mg, ca, li, mn, ni, co, cr, sc, te, wherein z≤0.3 and 0< x≤1, preferably 0< x <0.44 or 0.44≤x≤0.67 or 0.67< x≤1;

k _xM_u/2M'_v/2O_2+z, wherein u+v=2 and M, M' is selected from Mg, ca, li, mn, ni, co, cr, sc, te, wherein z is equal to or less than 0.3 and 0< x is equal to or less than 1, preferably 0< x is equal to or less than 0.44 or 0.44 is equal to or less than 0.67 or 0.67 is equal to or less than 1;

K _xM_u/3M'_v/3M''_w/3O_2+z wherein u+v+w=3 and M, M', M "is selected from Mg, ca, li, mn, ni, co, cr, sc, te, wherein z is equal to or less than 0.3 and 0< x is equal to or less than 1, preferably 0< x is equal to or less than 0.44 or 0.44 < x is equal to or less than 0.67 or 0.67< x is equal to or less than 1;

k _xMn_yNi_zFe_0.1Mg_0.1O₂, wherein 0.67≤x≤1.0, 0.5≤y≤0.7, and 0.1≤z≤0.3;

Prussian blue and/or Prussian blue analogues, abbreviated as PBA:

K _xM¹[M²'(CN)₆]_y.nH₂O,M¹ is a transition metal or transition metal alloy, M ²' is a transition metal, the transition metal and transition metal alloy being selected from Fe, ni, co and Mn, wherein 0≤x≤ 2;y≤1 and 0≤n≤12;

-a polyanionic compound:

K _xM₂(XO₄)₃, wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W, e.g. Na ₃V₂(PO₄)₃;

o K _xM₃(XO₄)₂(X₂O₇), wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

o K _xM(X₂O₇), wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

K _xM₂(XO₄)₂F₃, wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

k _xM₂(XO₄)₂F_3-yO_y, wherein 0< X is equal to or less than 4, m= V, fe, cr, mn, co, ni or Sc and 0.07 equal to or less than y is equal to or less than 0.12 and x= P, S, as, si, mo or W;

k _xM₂O₂(XO₄)₂ F, wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W;

k _xMXO₄, wherein 0< x+.4, m= V, fe, cr, mn, co, ni or Sc and x= P, S, as, si, mo or W.

Advantageously, the above electrode active material P is used for manufacturing a cathode.

Advantageously, the electrode active material P is selected from the group (D) formed by:

li ₄Ti₅O₁₂、Li₄Ti_5-xM_xO₁₂, where M= V, zr, hf, nb, ta and 0≤x≤0.25;

Niobium oxide and oxides of niobium mixed with titanium, germanium, cerium or tungsten, and is preferably selected from the group consisting of:

○ Nb₂O_5±δ、Nb₁₂WO_33±δ、Nb₁₄W₃O_44±δ、Nb₁₈W₁₆O_93±δ,Nb₁₆W₅O_55±δ, Wherein delta is more than or equal to 0 and less than or equal to 2, liNbO ₃,

TiNb ₂O_7±δ、Li_wTiNb₂O₇, wherein w is equal to or greater than 0, ti _1-xM¹ _xNb_2-yM² _yO_7±δ, or Li _wTi_1-xM¹ _xNb_2-yM² _yO_7±δ, wherein M ¹ and M ² are each at least one element selected from the group consisting of Nb, V, ta, fe, co, ti, bi, sb, as, P, cr, mo, W, B, na, mg, ca, ba, pb, al, zr, si, sr, K, cs and Sn, M ¹ and M ² may be the same or different from each other, and wherein 0≤w≤5 and 0≤x≤1 and 0≤y≤2 and 0≤delta≤0.3;

La _xTi_1-2xNb_2+xO₇, wherein 0< x <0.5;

○ M_xTi_1-2xNb_2+xO_7±δ,

wherein M is an element having an oxidation number of +III, more particularly M is at least one element selected from the group consisting of Fe, ga, mo, al, B and wherein 0< x≤0.20 and -0.3≤δ ≤0.3;Ga_0.10Ti_0.80Nb_2.10O₇;Fe_0.10Ti_0.80Nb_2.10O₇;

○ M_xTi_2-2xNb_10+xO_29±δ,

Wherein M is an element whose oxidation degree is +III, more particularly M is at least one element selected from the group consisting of Fe, ga, mo, al, B and wherein 0< x≤0.40 and-0.3≤ .delta≤0.3;

Ti _1-xM¹ _xNb_2-yM² _yO_7-zM³ _z or Li_wTi_1-xM¹ _xNb_2-yM² _yO_7-zM³ _z, therein

M ¹ and M ² are each at least one element selected from the group consisting of Nb, V, ta, fe, co, ti, bi, sb, as, P, cr, mo, W, B, na, mg, ca, ba, pb, al, zr, si, sr, K, cs and Sn,

The o's M ¹ and M ² may be the same or different from each other,

M ³ is at least one halogen,

O and wherein 0≤w≤5 and 0≤x not less than 1 and not less than 0 but not more than y 2 and z is less than or equal to 0.3;

TiNb ₂O_7-zM³ _z or Li _wTiNb₂O_7-zM³ _z, wherein M ³ is at least one halogen, preferably selected from F, cl, br, I or mixtures thereof, wherein 0 < z < 0.3 and 0 < w < 0.5;

○ Ti_1-xGe_xNb_2-yM¹ _yO_7±z、Li_wTi_1-xGe_xNb_2-yM¹ _yO_7±z、Ti_1-xCe_xNb_2-yM¹ _yO_7±z、Li_wTi_1- _xCe_xNb_2-yM¹ _yO_7±z, Wherein the method comprises the steps of

M ¹ is at least one element selected from the group consisting of Nb, V, ta, fe, co, ti, bi, sb, as, P, cr, mo, W, B, na, mg, ca, ba, pb, al, zr, si, sr, K, cs and Sn;

o is 0-5 and x is more than or equal to 0 and less than or equal to 1 and y is more than or equal to 0 and less than or equal to 2 and z is less than or equal to 0.3;

○ Ti_1-xGe_xNb_2-yM¹ _yO_7-zM² _z、Li_wTi_1-xGe_xNb_2-yM¹ _yO_7-zM² _z、Ti_1-xCe_xNb_2-yM¹ _yO_7-zM² _z、Li_wTi_1-xCe_xNb_2-yM¹ _yO_7-zM² _z, Wherein the method comprises the steps of

M ¹ and M ² are each at least one element selected from the group consisting of Nb, V, ta, fe, co, ti, bi, sb, as, P, cr, mo, W, B, na, mg, ca, ba, pb, al, zr, si, sr, K, cs, ce and Sn,

The o's M ¹ and M ² may be the same or different from each other,

O and wherein 0≤w≤5 and 0≤x not less than 1 and not less than 0 but not more than y2 and z is less than or equal to 0.3;

TiO ₂;TiO_xN_y, wherein x <2 and 0< y <0.2;

LiSiTON, tin and silicon based oxynitrides, more particularly formulation SiSn _0.87O_1.20N_1.72 and lithiated versions thereof;

A nitride and an MO _xN_y type oxynitride, wherein M is at least one element selected from Ge, si, sn, zn, co, ni, cu, fe or a mixture of one or more of these elements, wherein x is 0 or more and y is 0.3 or more;

Li _3-xM_x N, wherein M is at least one element selected from Cu, ni, co or a mixture of one or more of these elements and 0≤x≤1;

Li _3-xM_x N, wherein M is cobalt (Co) and 0≤x≤0.5, li _3-xM_x N, wherein M is nickel (Ni) and 0≤x≤0.6, li _3-xM_x N, wherein M is copper (Cu) and 0≤x≤0.3;

lithiated iron phosphate having a typical molecular formula LiFePO ₄;

Mixed silicon tin oxinitride of the typical formula Si _aSn_bO_yN_z, where a >0, b >0, a+b≤2, 0< y≤4, 0<z≤3, also known as SiTON, and especially SiSn _0.87O_1.2N_1.72, and oxinitride carbide of the typical formula Si _aSn_bC_cO_yN_z, where a >0, b >0, a+b≤2, 0< c <10, 0< y <24, 0< z <17;

Si _xN_y -type nitride, in particular wherein x=3 and y=4, sn _xN_y, in particular wherein x=3 and y=4, zn _xN_y, in particular wherein x=3 and y=2, li _3-xM_x N, wherein for m=co 0≤x≤0.5, for m=ni 0≤x≤0.6, for m=cu 0≤x≤0.3, si _3-xM_xN₄, wherein m=co or Fe and 0≤x≤0.3,

Oxide SnO ₂、SnO、Li₂SnO₃、SnSiO₃、Li_xSiO_y, where x > = 0 and 2>y>0,Li₄Ti₅O₁₂、TiNb₂O₇、Co₃O₄、SnB_0.6P_0.4O_2.9 and TiO ₂,

O Si, sn, siO ₂、SnO₂, siN, snN and mixtures thereof,

The composite oxide TiNb ₂O₇ comprising 0 to 10 wt% carbon, preferably carbon selected from graphene and carbon nanotubes;

Or selected from the group (E) consisting of:

si, ge, sn, sb, bi or P-based alloys and alloys of these different compounds

-Michaerenes, which are a two-dimensional class of materials with a stoichiometry of type M _n+1X_nT_x, wherein M is a transition metal, preferably chosen from Sc, ti, V, cr, Y, zr, nb, mo, hf, ta, W and X is chosen from C and/or N and the T surface terminator is chosen from F, cl, I, br, O, S, se, te, OH, NH ₂, 1≤n≤4

Conversion anode materials, e.g.

O.g ₂Ti₃O₇、G₄Ti₅O_12、GTi₂(PO₄)₃ oxide, G is Na or K

The oxides, sulfides, selenides, and phosphides of the following elements and their alloys Si, ge, sn, sb, bi.

Advantageously, the above electrode active material P is used for manufacturing an anode.

Another object of the invention is a porous electrode, in particular for an electrical energy storage device or an electrical energy production device, characterized in that it comprises at least one electrode active material P and an oxide electron conductor material, which is binder-free and has a porosity of 25 to 60% by volume, preferably 25 to 50% by volume.

Another object of the invention is a porous electrode obtainable by the method according to the invention. Another object of the invention is a porous electrode obtainable by the method according to the invention, characterized in that the porous electrode comprises at least one electrode active material P and an oxide electron conductor material, which is binder-free and has a porosity of 25 to 60% by volume, preferably 25 to 50% by volume.

Another object of the invention is a method for producing an electrical energy storage device or an electrical energy production device, implementing a method for producing a porous electrode according to the invention or using a porous electrode according to the invention, the device preferably being selected from the group consisting of a capacitor, a supercapacitor, a hybrid supercapacitor (such as a lithium-ion hybrid supercapacitor, a sodium-ion hybrid supercapacitor, a potassium-ion hybrid supercapacitor), a photovoltaic cell, a photoelectrochemical cell and a battery such as a lithium-ion battery, a sodium-ion battery, a potassium-ion battery. Another object of the invention is a method for producing an electrical energy storage device or an electrical energy production device, in particular a lithium ion, sodium ion or potassium ion battery, implementing a method for producing a porous electrode according to the invention, such as a battery, a capacitor, a supercapacitor, a hybrid supercapacitor (e.g. lithium ion hybrid supercapacitor, sodium ion hybrid supercapacitor, potassium ion hybrid supercapacitor), a photoelectrochemical cell, a photovoltaic cell.

Advantageously, when the electrical energy storage device or electrical energy production device is a lithium ion hybrid supercapacitor or lithium ion battery, the method of producing the cathode uses the electrode active material P selected in group (a), or the method of producing the anode uses the electrode active material P selected in group (D).

Advantageously, when the electrical energy storage device or electrical energy production device is a lithium-ion hybrid supercapacitor or lithium-ion battery, the method of producing the cathode uses the electrode active material P selected in group (B), or the method of producing the anode uses the electrode active material P selected in group (E) (G is Na, if necessary).

Advantageously, when the electrical energy storage device or electrical energy production device is a potassium-ion hybrid supercapacitor or potassium-ion battery, the method of producing the cathode uses the electrode active material P selected in group (C), or the method of producing the anode uses the electrode active material P selected in group (E) (G is Na, if necessary).

Advantageously, in the method of preparing a lithium ion battery, a method of preparing a porous electrode is performed to prepare a cathode with the electrode active material P selected from the group (a), or a method of preparing a porous electrode is performed to prepare an anode with the electrode active material P selected from the group (D).

In particular, this method is very suitable for the production of batteries, and in general, batteries according to the invention can be designed and dimensioned as surface mount assemblies (surface mount technology is often abbreviated to "SMT") so as to be compatible with manufacturing microelectronic methods, in particular with robotic methods for filling electronic circuit boards, termed "pick and place".

Advantageously, the porous electrode is impregnated with an electrolyte, preferably a phase carrying lithium, sodium or potassium ions, selected from the group consisting of:

Ionic liquid polymer;

A polymeric ion conductor made by adding a liquid electrolyte to the polymer phase or porous structure, or by an ion conductor polymer,

Another object of the invention is an electrical energy storage device or electrical energy production device obtainable by the method according to the invention, preferably a battery, preferably a lithium ion, sodium ion or potassium ion battery, obtainable by the method according to the invention.

Advantageously, the electrical energy storage device or electrical energy production device according to the invention is a capacitor, a supercapacitor, a hybrid supercapacitor (e.g. lithium-ion hybrid supercapacitor, sodium-ion hybrid supercapacitor, potassium-ion hybrid supercapacitor), a photovoltaic cell, a photoelectrochemical cell or a battery such as a lithium-ion battery, a sodium-ion battery or a potassium-ion battery.

Advantageously, when the electrical energy storage device or electrical energy production device is a lithium-ion hybrid supercapacitor or lithium-ion battery, the electrode active material P is selected for the cathode active material in group (a) and/or for the anode active material in group (D).

Advantageously, when the electrical energy storage device or electrical energy production device is a sodium-ion hybrid supercapacitor or sodium-ion battery, the electrode active material P is selected for the cathode active material in group (B) and/or for the anode active material in group (E) (G is Na, if necessary).

Advantageously, when the electrical energy storage device or electrical energy production device is a potassium-ion hybrid supercapacitor or potassium-ion battery, the electrode active material P is selected for the cathode active material in group (C) and/or for the anode active material in group (E) (G is K, if necessary).

The method according to the invention is particularly suitable for producing porous electrodes with a thickness of more than 1 μm, or even more than 3 μm, while ensuring a low series resistance of the battery.

Another object of the invention is an electrical energy storage device or electrical energy production device, such as a battery, a container, a supercapacitor, a photovoltaic cell or a photochemical cell, comprising a porous electrode according to the invention or obtainable by a method according to the invention.

Detailed Description

1. Definition of the definition

The present invention relates to a porous electrode covered with an oxide electron conductor material with an accessible surface, i.e. the outer surface of the electrode and the accessible inner pores of the electrode. The term "oxide electron conductor" includes oxide electron conductors and oxide electron semiconductors.

Within the scope of this document, the size of a particle is defined by its largest dimension. The term "nanoparticle" shall mean any particle or object of nanometer size having at least one dimension less than or equal to 400 nm.

The term "ionic liquid" shall mean any liquid salt capable of delivering electricity, which differs from molten salts in that the melting temperature is below 100 ℃. Some of these salts remain liquid at ambient temperature and do not cure even at very low temperatures. Such salts are known as "ambient temperature ionic liquids".

The term "electrolyte" refers to any ion-conducting material that is generated by the presence of mobile ions, and may be a solid without a liquid phase or a liquid. These ions are preferably Li+, na+ or K+. The liquid electrolyte may be in the form of a gel. To electrically isolate the electrodes, the electrolyte is electrically insulating.

The term "mesoporous" material shall mean any solid having pores within its structure, referred to as "mesopores", which have an intermediate dimension between micropores (width less than 2 nm) and macropores (width greater than 50 nm), i.e., a dimension of from 2 nm to 50 nm. The term corresponds to the term used by IUPAC (international union of pure and applied chemistry), which is a reference for a person skilled in the art. Thus, the term "nanopore" is not used herein, even though the mesopores defined above have a nano-size within the meaning of the definition of nanoparticle, it being understood that pores of size Yu Jiekong size are referred to by those skilled in the art as "micropores".

An introduction to the concept of porosity (and the terms explained immediately above) is given in the article "Texture DES MATERIALS pulverulents ou poreux" (Texture of powdery or porous materials) by rouquerol et al, page 1050 of the "Techniques de l'Ingénieur" (Techniques for the Engineer), treaties, Analyse et Caractérisation(Analysis and Characterisation), division, which also describes techniques for characterizing porosity, in particular the BET method.

Within the meaning of the present invention, the term "porous layer" refers to a layer having a plurality of pores. The term "mesoporous layer" refers to a layer having mesopores. In these layers, pores and mesopores contribute significantly to the total porous volume, which is revealed by the expression porous/mesoporous layer with a porosity of more than X volume% as used in the present description.

The term "aggregate" refers to a weakly bound aggregate of primary particles according to the IUPAC definition. In this case, these primary particles, preferably nanoparticles, are particles having a diameter that can be determined by transmission electron microscopy. The aggregates of aggregated primary nanoparticles can be destroyed (i.e., reduced to primary nanoparticles) typically by ultrasound in suspension in a liquid phase using techniques known to those skilled in the art.

The term "agglomerates" refers to a strongly bound collection of primary particles or aggregates, according to the IUPAC definition.

2. Preparation of nanoparticle suspensions

The porous electrode according to the invention is formed from a colloidal suspension or paste of clusters and/or agglomerates of nanoparticles.

In a more preferred embodiment of the present invention, the nanoparticles having their primary size are directly prepared by precipitation, pechini synthesis, spray pyrolysis, hydrothermal synthesis or solvothermal synthesis. Hydrothermal synthesis or solvothermal synthesis can be used to obtain nanoparticles, preferably nanoparticles with a very narrow size distribution, known as "monodisperse nanoparticles". The size of these non-aggregated or non-agglomerated nanopowders/nanoparticles is referred to as the primary size. It is generally between 2 nm and 400 nm, preferably between 2 nm and 100 nm, more preferably between 2 nm and 60 nm, advantageously between 10 nm and 50 nm, preferably between 10 nm and 30 nm, which promotes the formation of interconnected electron and ion conducting mesoporous networks by the "necking" phenomenon in the subsequent process steps.

Additives, such as binders, may also be added to the suspension of nanoparticles (clusters and/or aggregates of nanoparticles, which are also known to be in the form of nanoparticles) to promote the creation of deposits or green sheets (GREEN SHEET), particularly thick deposits without cracks.

A layer of at least one oxide electron conductor material precursor is formed on these preferably monodisperse aggregates and/or agglomerates of primary nanoparticles of at least one electrode active material P by any suitable means.

3. A mixture comprising at least one oxide electron conductor material precursor and a colloidal suspension or paste comprising aggregates and/or agglomerates of primary particles of at least one electrode active material P. A layer of at least one oxide electron conductor material precursor is formed on the aggregates and/or agglomerates of primary particles of at least one electrode active material P.

Very advantageously, the layer of oxide electron conductor material may be obtained in various ways and by any suitable way, in particular by contacting a colloidal suspension, paste comprising aggregates or agglomerates of primary nanoparticles of at least one electrode active material P with a liquid phase containing at least one oxide electron conductor material precursor, followed by conversion of said one or more electron conductor material precursors into an electron conductor material.

More generally, using the techniques described herein for producing a coating of at least one oxide electron conductor material precursor, only the accessible surface of the aggregates or agglomerates of primary nanoparticles of at least one electrode active material P is covered.

The formation of the layer of at least one precursor of an oxide electron conductor material on the aggregates or agglomerates in the form of a suspension or paste is advantageously carried out in the presence of a complexing agent such as polyvinylpyrrolidone (PVP) to promote complexation of one or more precursors at the surface of the aggregates/agglomerates.

The method is simple, quick and easy to implement. Advantageously, the one or more precursors of the electronically conductive material are selected from organic salts containing one or more metallic elements capable of forming an oxide electronic conductor after a heat treatment such as calcination (preferably carried out in air or an oxidizing atmosphere). The oxide electron conductor may optionally comprise at least one doping element. These metal elements, preferably metal cations, may advantageously be selected from tin, zinc, indium, gallium, molybdenum or mixtures of two or three or four of these elements. The organic salt is preferably selected from:

Acetate of at least one metal element capable of forming an oxide electronic conductor after a heat treatment, such as calcination, preferably carried out in air or an oxidizing atmosphere.

In order to obtain a layer of electron-conducting material (preferably oxide electron-conducting material) formed of alkoxide, nitrate, oxalate or acetate on the aggregates or agglomerates of primary nanoparticles of at least one electrode active material P, a colloidal suspension or paste comprising said aggregates or agglomerates of nanoparticles may be contacted with a solution enriched in the desired electron-conducting material precursor.

It is a mixture of such a colloidal suspension or paste comprising aggregates or agglomerates of primary nanoparticles of electrode active material P and at least one oxide electron conductor material precursor, which is then used to produce a porous dried layer and an electrode according to the invention. The mixture of the colloidal suspension or paste comprising aggregates or agglomerates of primary nanoparticles of the electrode active material P and at least one oxide electron conductor material precursor is hereinafter referred to as "mixture according to the invention". Advantageously, the mixture according to the invention is in the form of a colloidal suspension or paste (ink).

4. Manufacture of porous layers

The method of producing an electrode according to the present invention comprises applying a mixture of colloidal suspensions or pastes comprising aggregates or agglomerates of one or more oxide electron conductor material precursors and at least one primary nanoparticle of an electrode active material P onto a substrate to form a layer, and then drying the layer to obtain a porous layer. In order to increase the thickness of the porous layer, the sequence comprising applying the mixture to the substrate to form a layer and drying may be repeated a number of times. The final thickness of the porous layer is advantageously less than or equal to 5mm, preferably from about 1 μm to about 500 μm. The thickness of the porous layer is advantageously less than 500 μm, preferably from about 2 μm to about 400 μm, more preferably from 2 μm to 300 μm, still more preferably from 3 μm to 200 μm. In general, the mixtures according to the invention are deposited on the substrate in the form of colloidal suspensions or pastes by any suitable technique, in particular by means of electrophoresis, extrusion, additive manufacturing (or robot casting), ink-jet printing, spraying, flexographic printing, coating processes, preferably using doctor blades (known by the term "doctor blade (doctor blade)" or "cast"), roll coating, curtain slot die coating or dip coating.

In order to give the mixtures according to the invention a viscosity suitable for the coating techniques usually used for the manufacture of electrodes and thus to be deposited on a substrate, it is advantageous to use the mixtures according to the invention in the form of colloidal suspensions or pastes having a solids content of less than 30% by weight.

According to the applicant's findings, in case the average diameter of the aggregates or agglomerates of nanoparticles is 50 nm to 900 nm, preferably 100 nm to 800 nm (more preferably 100 nm to 400 nm), during the subsequent step of the method, a mesoporous layer with an average diameter of mesopores of 2 nm to 100 nm is obtained.

According to the invention, the porous layer may be deposited from the mixture according to the invention in the form of a highly concentrated suspension of nanoparticles comprising at least one oxide electron conductor material precursor and an active material P, by an inkjet printing method or by a coating method (in particular dip coating, roll coating, curtain coating, slot extrusion coating, or by doctor blade coating).

The porous electrode layer may also be deposited by electrophoresis, but the mixture according to the invention is advantageously used in the form of a suspension of a relatively low concentration comprising an agglomeration of nanoparticles of at least one oxide electron conductor material precursor and the active material P.

The method of depositing the mixture according to the invention by electrophoresis, extrusion, additive manufacturing, dip coating, ink jet, roll coating, curtain coating, doctor blade coating or slot die coating is a simple, safe, easy to implement and industrial method and enables to obtain a uniform final porous layer. Electrophoretic deposition makes it possible to deposit layers uniformly over a large surface at high deposition rates. Coating techniques, particularly those mentioned above, can simplify the management of the bath compared to electrophoretic deposition techniques, since the particles in suspension are not depleted during deposition. Deposition by inkjet printing can achieve localized deposition.

The thick porous layer, preferably having a thickness of 50 to 400 μm, can be produced in a single step by roll coating, curtain coating, slot die coating or by doctor blade coating (i.e. with a blade) or by extrusion.

The properties of the technique of depositing the mixture according to the invention in the form of a colloidal suspension or paste (ink) and of the deposition method must be adapted to the viscosity of the colloidal suspension or paste (ink) used and vice versa.

The substrate is advantageously an intermediate substrate or a substrate that can be used as a current collector.

4.1 Substrate capable of functioning as a current collector

In a first embodiment, the substrate is a substrate capable of acting as an electrical sub-fluid and is advantageously compatible with the heat treatment used in the method according to the invention. The substrate may advantageously be a metal substrate or a substrate made of electronically conductive carbon, in particular a substrate based on graphite, graphene and/or carbon nanotubes. The substrate on which the mixture according to the invention is deposited in the form of a colloidal suspension or paste (ink) ensures the current collector function of the electrode. The mixtures according to the invention in the form of colloidal suspensions or pastes (inks) can be deposited on one or both sides of the substrate, in particular by the deposition techniques described above.

The current collector in the electrochemical device using the electrode according to the present invention may be a substrate stable in the potential operation range of the electrochemical device. In a battery employing an electrode according to the invention, the current collector must be a substrate that is stable over a range of potentials (preferably, 2.5V to 5V for the cathode and 0V to 2.5V for the anode) relative to the potential of lithium. Advantageously, a metal substrate, such as a metal tape (i.e. a laminated metal sheet), is selected. The substrate may be made of tungsten, molybdenum, chromium, titanium, tantalum, zirconium, niobium, stainless steel or an alloy of two or more of these materials, among others. Such a metal substrate is quite expensive and can add significantly to the cost of the battery. Tungsten, molybdenum, chromium, titanium, tantalum, zirconium, niobium, stainless steel and alloys thereof are particularly resistant to high temperature heat treatment and, therefore, they are particularly suitable for use as sinterable electrode substrates. The reason for using these heat-resistant treated substrates is that it is possible to sinter the deposit, preferably a thin deposit, directly on the substrate.

It is also possible to cover such a substrate capable of acting as an electrical sub-fluid with a conductive or semiconductive oxide before depositing the mixture according to the invention in the form of a colloidal suspension or paste (ink), which makes it possible in particular to protect less noble substrates, such as copper, nickel, aluminum and carbon, in particular in the form of graphite. Thus, these less noble substrates may be used as electrode substrates, in particular due to their cost. It may involve conductive carbon sheets (typically made of graphite), metal sheets or non-metal sheets that are metallized (i.e. covered with a metal layer). The substrate is preferably selected from the group consisting of strips made of copper, nickel, molybdenum, tungsten, tantalum, chromium, niobium, zirconium, titanium, and alloy strips containing at least one of these elements. Stainless steel may also be used. These substrates have the advantage of being stable and resistant to heat treatment over a wide range of potentials.

Copper, nickel, molybdenum and alloys thereof are preferably used as the anode substrate. Carbon-based substrates, in particular substrates in the form of graphite, based on nickel-chromium, stainless steel, chromium, titanium, aluminum, tungsten, molybdenum, tantalum, zirconium, niobium alloys or alloys containing at least one of these elements, are preferably used as cathode electron current collector substrates. These anode and/or cathode substrates may or may not be coated with an electrochemically inert conductive layer. Such layers may be prepared by depositing nitrides, carbides, graphite, gold, palladium and/or platinum.

The mixture according to the invention in the form of a colloidal suspension or paste (ink) can be deposited on one or both sides of a substrate capable of acting as a current collector. The layer deposited on the substrate is then dried to obtain a porous layer comprising the electrode active material P and at least one precursor of the active electron conductor material.

The conversion of one or more oxide electron conductor material precursors to an oxide electron conductor material is then carried out on the porous dried layer, which is initially deposited on one or both sides of a substrate capable of functioning as a current collector.

4.2 Intermediate substrate

According to a second embodiment, the mixture according to the invention comprising the electrode active material P and at least one precursor of the active material electron conductor (ink) in the form of a colloidal suspension or paste is not deposited on a substrate capable of functioning as a current collector, but on an intermediate substrate, which is usually used in a temporary manner.

In this embodiment, the mixture according to the invention is deposited in the form of a colloidal suspension or paste (ink) on one face of the intermediate substrate, so that the obtained layer can be easily separated from the intermediate substrate afterwards.

In particular, a rather thick layer, called a "green sheet", may be deposited from the mixture according to the invention in the form of a suspension or paste comprising at least one oxide electron conductor material precursor and aggregates and/or agglomerates of nanoparticles of the electrode active material P, preferably from a concentrated suspension (i.e. less fluid, preferably pasty) comprising at least one oxide electron conductor material precursor and aggregates and/or agglomerates of nanoparticles of the electrode active material P. These thick layers may be deposited by any suitable method, in particular by inkjet printing methods, extrusion, additive manufacturing, spraying, flexographic printing, coating methods (doctor blade coating, roll coating, curtain coating, slot die coating or dip coating).

The method of depositing nanoparticles by dip coating, inkjet printing, roll coating, curtain coating, slot die coating, extrusion, additive manufacturing, spray coating, flexographic printing or doctor blade coating is simple, safe, easy to implement and industrialize, and can obtain a uniform deposit. Inkjet printing allows the deposition of the mixture according to the invention in a localized manner in the same way as doctor blade deposition under a mask. Thick layers can be obtained in a single step by roll coating, curtain coating, slot die coating, dip coating, extrusion, additive manufacturing or knife coating techniques.

The intermediate substrate may be a flexible substrate, which may be a polymer sheet, such as polyethylene terephthalate, abbreviated PET. In this second embodiment, the deposition step is advantageously carried out on one face of the intermediate substrate, so as to separate the layer from its substrate at a later time. In this second embodiment, the layer is separated from its substrate after drying and prior to any high temperature heat treatment. The thickness of the dried layer is advantageously less than or equal to 5mm, advantageously from about 1 μm to about 600 μm. The thickness of the layer after drying is advantageously less than 500 μm, preferably from about 3 μm to about 400 μm, more preferably from 3 μm to 300 μm.

In the second embodiment, a method of producing an electrode of an electrochemical device (e.g., a battery) uses an intermediate substrate preferably made of a polymer (e.g., PET), and produces a tape called "green tape". After drying, the green tape is then separated from its substrate, and then formed from a support plate or sheet (herein, hereinafter the term "plate" is used regardless of its thickness).

A process of converting one or more oxide electron conductor material precursors into an oxide electron conductor is then performed on these self-supporting porous plates or sheets.

5. Converting one or more oxide electron conductor material precursors present in the porous dried layer to an oxide electron conductor material

The self-supporting porous dried layer or porous plate comprising the electrode active material P and at least one precursor of the active material electron conductor is preferably heat treated in air or an oxidizing atmosphere at a sufficient temperature to convert the oxide electron conductor material or materials precursor(s) in question into an oxide electron conductor material. Thereby forming a region of electrode active material P which is at least partially covered by a coating of an electron conductor material, preferably a coating of an oxide electron conductor material, more preferably SnO ₂, aluminum doped ZnO (ZnO: al, preferably having a molar ratio Zn: al of 1:0.015 to 1:0.05), in ₂O₃、Ga₂O₃、MoO₃、SrMoO₃, a mixture comprising two of these oxides (for example indium tin oxide corresponding to a mixture of indium oxide (In ₂O₃) and tin oxide (SnO ₂)), a mixture of three of these oxides, a mixture of four of these oxides, a mixture of five of these oxides or a coating of a mixture of six of these oxides, in a fully distributed manner throughout the interior volume and surface of the electrode.

The heat treatment is preferably carried out in an oxidizing atmosphere, and can eliminate organic components, i.e., to effect debonding. Depending on the nature of the electrode active material P used and the temperature used to convert the oxide electron conductor material precursor or precursors in question into an oxide electron conductor material, the heat treatment also enables curing of the layer or porous plate, as will be explained in more detail in the following sections.

With respect to the prior art, in particular porous electrodes comprising carbon coatings on and in the pores of the electrode as described in application WO2021/220174, the presence of the region of the electrode active material P covered at least partially by the coating of the oxide electron conductor material, preferably by the coating of the oxide electron conductor material, in a perfectly distributed manner over the whole internal volume and surface of the electrode, gives the electrode a better electrochemical performance at high temperatures and significantly increases the stability of the electrode. The fact that this single three-dimensional structure (comprising the region of the electrode active material P covered at least partially by the coating of the oxide electron conductor material over the whole internal volume and the surface of the electrode, preferably comprising the region of the electrode active material P covered by the coating of the oxide electron conductor material over the whole internal volume and the surface of the electrode) gives in particular better performance of the final electrode. More specifically, the presence of the electrode active material P region at least partially covered by, preferably covered by, the coating of the oxide electronic conductor material over the entire internal volume and surface of the electrode may improve the final performance of the electrode, in particular the voltage stability of the electrode and its temperature stability, and improve the electrochemical stability of the electrode, in particular when it is to be in contact with a liquid electrolyte, to reduce the polarization resistance of the electrode, and this even when the electrode is thicker. When the electrode is thicker and/or the active material resistance of the porous layer is too high, it is particularly advantageous to use electron conductor materials In the form of oxides (In particular In ₂O₃、SnO₂, aluminum doped ZnO (ZnO: al, preferably with a molar ratio Zn: al of 1:0.015 to 1:0.05), ga ₂O₃ or one or more of these oxides or a mixture of these doped oxides) In the electrode volume.

The electrode according to the invention is porous, preferably mesoporous, and its specific surface area is advantageously large. Increasing the specific surface area of the electrode increases the exchange surface area and thus the power of the battery, but also accelerates parasitic reactions. The presence of these electron conductor coatings in the form of oxides in the electrode volume will cause these parasitic reactions to be blocked.

Furthermore, due to the fact that the specific surface area is very large, the effect of these oxide-form electron conductor coatings on the electron conductivity of the electrode will be more pronounced than in the case of conventional electrodes with smaller specific surface areas, even if the deposited conductor coating has a lower thickness. These oxide electron conductor coatings deposited within the volume of the electrode of the porous layer impart excellent electron conductivity to the electrode, particularly when the porous layer is formed of an electrode active material having poor electron conductivity. The oxide electron conductor material layer can improve the conductivity of the electrode while limiting the dissolution of the electrode, thereby making it possible to increase the power of the battery, particularly since the coating layer of the oxide electron conductor material having the electrode active material region P has a lower thickness.

This is essentially a unitary structure of the porous electrode produced according to the method of the present invention (including the electrode active material P region covered by the coating of oxide electron conductor material over the entire internal volume and surface of the electrode), which makes it possible to improve the final properties of the electrode, in particular to obtain a thick electrode without increasing the internal resistance of the electrode.

The thickness of the oxide electron conductor material coating covering the electrode active material P region is less than 10 nm a, preferably less than 7 a nm a, more preferably less than 5a nm a, still more preferably from 5a nm a to 3a nm a, still more preferably less than 3a nm a. The oxide electron conductor material coating over the entire internal volume of the electrode advantageously has an optimal thickness, which coating must be thick enough to improve electron conduction and thin enough not to impede ion conduction within the electrode and ultimately not to degrade the performance of the electrical energy storage device or electrical energy production device (e.g., a battery). In addition, the coating imparts good electron conductivity to the electrode due to the large specific surface area of the electrode.

Advantageously, the electron conductor material may be an oxide electron conductor material, preferably selected from:

Tin oxide (SnO ₂), aluminum-doped zinc oxide (ZnO: al) (preferably with a molar ratio Zn: al of 1:0.015 to 1:0.05), indium oxide (In ₂O₃), gallium oxide (Ga ₂O₃), molybdenum oxide (MoO ₃), strontium molybdenum oxide (SrMoO ₃), mixtures of two of these oxides (for example indium tin oxide corresponding to a mixture of indium oxide (In ₂O₃) and tin oxide (SnO ₂)), mixtures of three of these oxides, mixtures of four of these oxides, mixtures of five of these oxides or mixtures of six of these oxides,

Doped oxides based on zinc oxide, preferably doped with gallium (Ga) and/or aluminum (Al) and/or boron (B) and/or beryllium (Be), and/or chromium (Cr) and/or cerium (Ce) and/or titanium (Ti) and/or indium (In) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or manganese (Mn) and/or germanium (Ge) and/or molybdenum (Mo),

Doped oxides based on indium oxide, preferably doped with tin (Sn) and/or gallium (Ga) and/or chromium (Cr) and/or cerium (Ce) and/or titanium (Ti) and/or indium (In) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or manganese (Mn) and/or germanium (Ge) and/or molybdenum (Mo),

Doped tin oxide, preferably doped with arsenic (As) and/or fluorine (F) and/or nitrogen (N) and/or niobium (Nb) and/or phosphorus (P) and/or antimony (Sb) and/or aluminum (Al) and/or titanium (Ti) and/or gallium (Ga) and/or chromium (Cr) and/or cerium (Ce) and/or indium (In) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or manganese (Mn) and/or germanium (Ge) and/or molybdenum (Mo),

-Doped oxides based on molybdenum oxide, preferably doped lithium (Li) and/or sodium (Na) and/or potassium (K) and/or beryllium (Be) and/or magnesium (Mg) and/or calcium (Ca) and/or scandium (Sc) and/or titanium (Ti) and/or vanadium (V) and/or chromium (Cr) and/or manganese (Mn) and/or iron (Fe) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or zinc (Zn) and/or gallium (Ga) and/or germanium (Ge) and/or arsenic (As) and/or rubidium (Rb) and/or cesium (Cs) and/or yttrium (Y) and/or zirconium (Zr), and/or strontium (Sr) and/or tritium (Nb) and/or tritium (T) and/or iridium (Ir) and/or platinum (Pt) and/or gold (Au) and/or mercury (Pb) and/or bismuth (Pb).

6. The porous layer comprising the electrode active material P and the oxide electron conductor material is consolidated to obtain a porous, preferably mesoporous, electrode.

The porous layer or the self-supporting porous plate may then be subjected to a heat treatment, if necessary, preferably in an oxidizing atmosphere, to eliminate the organic components. The porous layer or the self-supporting porous plate may then be consolidated. Such consolidation may be carried out by pressing and/or heat treatment, i.e. by heat treatment (heating), by heat treatment followed by mechanical treatment, and optionally by thermo-mechanical treatment (typically hot pressing). In a very advantageous embodiment of the invention, this treatment results in partial coalescence of the primary nanoparticles into aggregates or agglomerates on the one hand and partial coalescence between adjacent aggregates or agglomerates by the presence of a coating of the oxide electron conductor material on the other hand, a phenomenon known as "necking" or "neck formation". Characterized in that the two contacting particles are partially agglomerated, which remain separate but are connected by a (restricted) neck. Lithium ions and electrons are mobile within these necks and can diffuse from one particle to another without encountering grain boundaries. The nanoparticles are bonded together to ensure electron conduction from one to the other. Adjacent aggregates or agglomerates are bonded together by the presence of the oxide electron conductor coating to ensure electron conduction from one aggregate or agglomerate to another. Electron conduction occurs in two different ways, in particular by nanoparticles of electrode active material P (1) being bonded together, and adjacent aggregates or agglomerates being bonded together by oxide electron conductor material (2), which is schematically shown in fig. 1.

Thus, the rigid mesoporous film without organic binder is formed from primary nanoparticles of the electrode active material P (1) and the oxide electron conductor material (2), forming a three-dimensional network with high ion mobility and electron conductivity, comprising interconnected pores, preferably mesopores. The porous layer, preferably a mesoporous layer, thus obtained is very suitable for impregnating the pores of an electrode with an ion conductor material that penetrates into the depth of the open porous structure of the layer.

The temperature required to obtain "necking" depends on the material, and the duration of the treatment depends on the temperature in view of the diffusion properties that lead to the phenomenon of necking. This method can be called sintering, and depending on its duration and temperature, a more or less pronounced coalescence (necking) is obtained, which has an effect on the porosity. Thus, electrodes of the desired porous or mesoporous ceramic structure with controlled porosity can be obtained while maintaining a completely uniform channel size. During such a thermo-mechanical or heat treatment the electrode layer will be free of any organic components and residues (e.g. liquid phase of the suspension of nanoparticles, binder and optionally surfactant product) that it becomes an inorganic (ceramic) layer.

The thickness of the porous electrodes or plates centered in this way is advantageously less than or equal to 5mm, advantageously about 1 μm to about 500 μm. The thickness of the porous plate after sintering is advantageously from 2 μm to 400 μm, preferably from 2 μm to about 300 μm, preferably from 3 μm to 200 μm.

According to a second embodiment, in order to obtain a porous electrode provided on a substrate capable of functioning as a current collector, there is also provided a conductive sheet covered on at least one of its faces, preferably on both of its faces, with a thin layer of conductive adhesive (loaded with graphite), or with a sol-gel deposit of conductive particles. The thin layer preferably has a thickness of less than 1 μm. The electronically conductive sheet may be a metal tape or a graphite sheet.

When the electronically conductive sheet is a metal, it is preferably a laminate sheet, i.e., obtained by lamination. Lamination may optionally be followed by a final anneal, which may be a softening anneal (in whole or in part) or a recrystallization, depending on metallurgical terms. Plates obtained by electrolytic deposition, such as electrodeposited copper sheets or electrodeposited nickel sheets, may also be used.

Then, after consolidation (i.e., sintering), the conductive sheet is placed on a plate or interposed between two previously obtained plates. The assembly is then advantageously pressed such that the intermediate thin layer of conductive adhesive promotes adhesion of the board to the substrate and forms a board/substrate or board/substrate/board assembly in order to obtain a rigid integrated sub-assembly.

One advantage of the second embodiment is that it allows for the use of cheaper substrates such as aluminium, copper or graphite tape. More specifically, the fact that these strips cannot withstand the heat treatment used to consolidate the deposited layers, and that they are bonded to the board after their heat treatment, also makes it possible to prevent them from oxidizing.

The plate/substrate or plate/substrate/plate subassembly thus obtained can be used for producing electrochemical devices, such as batteries.

Optionally, a porous electrode, preferably a self-supporting porous plate, according to the present invention may be impregnated with an ion conducting phase, i.e. a phase comprising at least one ion conductor material, such as an ion conductor polymer or an ionic liquid polymer. Such ion conductor materials may also be electronically conductive. The ion conductor material may be of different types. They may be liquids in gel form or solids. The impregnation of the solid ionic conductor is advantageously carried out by using the ionic conductor in the molten state or dissolved in a solvent, which is then evaporated. The ion conducting phase may comprise or be an ion conducting polymer, preferably selected from polyethylene oxide (PEO), polyacrylonitrile (PAN), poly (methyl methacrylate) (PMMA), poly (propylene carbonate) (PPC), poly (ethylene carbonate) (PEC, poly (ethylenecarbonate)), poly (ethylene carbonate) (PVC, poly (vinylcarbonate)), polyvinylidene fluoride (PVDF), polypropylene glycol (PPG), poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polydimethylsiloxane (PDMS), poly (epsilon-caprolactone) (PCL) and poly (trimethylene carbonate) (PTMC).

In the pores of the porous electrode, the ion conductor polymer is preferably present in the pores of the self-supporting porous plate, giving it better mechanical rigidity. The use of porous electrodes impregnated with ion conductor polymers according to the invention in energy storage devices or energy production devices such as batteries may increase their service life.

Optionally, a layer may be deposited on top of the porous electrode according to the invention, which layer is electronically insulating and has good ionic conductivity, the deposited layer typically having a thickness of about 0.5 nm to 20 nm, preferably less than 5 nm, and even more preferably less than 2 nm.

The ion conducting and electrically insulating layer may be inorganic or organic in nature. More specifically, inorganic layers that may be used include, for example, lithium ion oxide, phosphate or borate conductors, and organic layers that may be used include polymers (e.g., PEO or tetrafluoroethylene sulfonate copolymers optionally containing lithium salts, such as Nafion (TM), CAS number 31175-20-9). Such an ion-conducting and electrically insulating layer must be in stable contact with the electrode it is deposited on. A borate conductor of lithium ions is preferably used for the cathode.

Such an ion conducting and electrically insulating layer makes it possible to limit the dissolution of ions from the electrode and their migration to the electrolyte, it being understood that in an electrode made of LiMn ₂O₄, manganese risks dissolution in certain liquid electrolytes, especially at high temperatures.

When the electrode according to the invention is covered with an ion-conducting layer, it is the latter that ensures mainly a protective function (in particular avoiding dissolution of the electrode), as described above.

In summary, according to the invention, the presence of the region of the electrode active material P at least partially covered with a coating of an oxide electron conductor material, preferably a coating of an oxide electron conductor material, in the entire internal volume of the electrode and on the surface of the porous electrode allows at least an increase in the electron conductivity and, depending on the nature of the oxide electron conductor material, advantageously protects the electrode from dissolution in the electrolyte at high temperatures. According to the invention both effects are obtained only by a single arrangement of the oxide electron conductor material in the whole internal volume and on the electrode surface, or this specific arrangement of the oxide electron conductor material in the whole internal volume of the electrode according to the invention is insufficient to obtain both effects, in which case e.g. an ion-conducting and electronically insulating layer can be deposited on and in the pores of the electrode according to the invention in order to obtain additional protection at high temperatures.

According to the first and second embodiments, a porous electrode according to the invention is obtained, which is arranged on or on either side of a metal substrate used as an electrical sub-fluid. The electrode/substrate/electrode sub-assembly thus obtained by the first or second embodiment may be used for the production of electrochemical devices such as batteries, in particular microcells. The assembly by thermal bonding may also be performed by stacking and hot-pressing components of the structure of an electrochemical device, such as a battery, in particular a microcell, in which case a multi-layered stack comprising a first anode according to the invention, a metal substrate thereof, a second anode according to the invention, a solid electrolyte layer or electrolyte separator, a first cathode according to the invention, a metal substrate thereof, a second cathode according to the invention, a new solid electrolyte layer or new electrolyte separator, etc. is assembled.

The electrode/substrate/electrode sub-assembly may be used to produce electrochemical devices such as batteries (especially microcells). Regardless of the electrode/substrate/electrode subassembly embodiment, the electrolyte membrane or electrolyte separator is then deposited on the latter. Then, the necessary cuts are made to produce a cell with multiple basic cells, then the subassemblies are stacked (typically "head-to-tail") and hot pressed to join the anode and cathode together at the solid electrolyte.

Or the cuts required to produce a cell having multiple basic cells may be made before depositing electrolyte membranes or electrolytic separators on each anode/substrate/anode and cathode/substrate/cathode sub-assembly. The anode/substrate/anode sub-assembly and/or the cathode/substrate/cathode sub-assembly is then covered with an electrolyte membrane or an electrolytic separator, the sub-assemblies are then stacked and hot pressed to join the anode and cathode together at the electrolyte membrane or electrolytic separator and, if desired, the resulting stack is impregnated with an electrolyte, preferably a phase carrying lithium, sodium or potassium ions.

In both alternatives just proposed, the bonding by hot pressing can be performed at relatively low temperatures, in particular when the electrode according to the invention is impregnated with an ion conductor material, which may be an ion conductor polymer or an ionic liquid polymer. For this reason, oxidation of the substrate metal layer was not observed.

Examples

Example 1 production of LiMn ₂O₄ -based cathode according to the invention

An aqueous suspension of LiMn ₂O₄ nanoparticles was prepared by hydrothermal synthesis according to the method described in the article by lindle et al titled "A new one pot hydrothermal synthesis and electrochemical characterisation of Li_1+xMn_2-yO₄spinel structured compounds", Energy & Enviro nmental Science (2010), volume 3, pages 1339-1346:

14.85g of LiOH.H ₂ O were dissolved in 500mL of water. 43.1g of KMnO ₄ was added to the solution, and the liquid phase was poured into an autoclave. 28ml of isobutyraldehyde and water were added with stirring until a total volume of 3.54L was obtained. The autoclave was then heated to 180 ℃ and held at that temperature for 6 hours. After slow cooling, a suspension of the black precipitate in a solvent was obtained. The precipitate was subjected to a series of centrifugation steps in water-redispersion in water until an agglomerated suspension with a conductivity of about 300. Mu.S/cm and a zeta potential of-30 mV was obtained. The aggregates obtained are formed from aggregated primary particles having a size of 10 to 20 nm. The aggregates obtained have a spherical shape and an average diameter of about 150 nm, which were characterized by x-ray diffraction and electron microscopy.

1G of polyvinylpyrrolidone (abbreviated as PVP) having a molecular weight of 55,000g/mol was added to 50mL of distilled water at 40℃and then 3g of tin oxalate SnC ₂O₄ was added to the PVP aqueous solution.

The LiMn ₂O₄ suspension was re-concentrated by centrifugation and the particles were re-dispersed in the necessary volume of water to obtain a 16 wt% paste. The volume of aqueous solution of PVP and tin acetate (corresponding to a ratio of 10 mass% of tin acetate to LiMn ₂O₄) and the required amount of water were then added to the LiMn ₂O₄ suspension of nanoparticle aggregates to obtain a final aggregate suspension with a solids content of 10%.

The ink thus obtained was applied to a stainless steel (316L) belt having a thickness of 5. Mu.m. The obtained layer was dried in a temperature controlled oven. The thickness of the obtained layer was about 6 μm.

This layer is then heat treated in air at 600 ℃ for 5 hours, on the one hand in order to convert the precursor tin acetate of the oxide electron conductor material into SnO ₂, i.e. into the oxide electron conductor material, to remove reaction by-products, and on the other hand in order to join the primary nanoparticles together by the presence of the oxide electron conductor material SnO ₂ formed and in order to join adjacent aggregates together, in order to improve the adhesion to the substrate and in order to perfect the recrystallization of LiMn ₂O₄. The porous layer thus obtained had an open porosity of about 45% by volume, with pores having a size of 10 nm to 20 nm.

Example 2 production of Li ₄Ti₅O₁₂ -based mesoporous anodes according to the invention

Li ₄Ti₅O₁₂ nanoparticle suspension was prepared by sugar thermal synthesis 190 mL1, 4-butanediol was poured into a beaker and 4.25 g lithium acetate was added with stirring. The solution was kept stirring until the acetate was completely dissolved. 16.9 g titanium butoxide was taken under an inert atmosphere and introduced into the acetate solution. The solution was then stirred for several minutes and then transferred to an autoclave preloaded with another 60 mL butanediol. The autoclave was then closed and purged with nitrogen for at least 10 minutes. The autoclave was then heated to 300 ℃ at a rate of3 ℃/min and held at that temperature for 2 hours with stirring. Finally, it was allowed to cool while stirring was continued.

A suspension of white precipitate in solvent was obtained. The precipitate is subjected to a series of centrifugation steps-redispersion in ethanol to obtain a pure colloidal suspension with low ionic conductivity. It comprises an aggregate of about 150 nm formed from primary particles of 10 nm. Zeta potential was about-45 mV. The product was characterized by x-ray diffraction and electron microscopy.

Polyvinylpyrrolidone (abbreviated as PVP) having a molecular weight of 55,000 g/mol at 1 g was added to 50 mL ethanol at 40 ℃, and then 3 g tin oxalate was added to the PVP solution.

Then, to this suspension of Li ₄Ti₅O₁₂ nanoparticle aggregates, the volume of the aqueous solution of PVP and tin acetate (corresponding to the ratio of 10 mass% of tin acetate to LiMn ₂O₄) was added. Ethanol was evaporated until the suspension of aggregates had a solids content of 10%. The ink thus obtained was applied to a stainless steel (316L) belt having a thickness of 5. Mu.m. The obtained layer is dried in an oven with controlled temperature and humidity to avoid the formation of cracks during drying. The ink deposition and drying were then repeated to obtain a layer about 4 μm thick. The layer was then heat treated in air at 600 ℃ for 5 hours. This heat treatment is capable of converting the precursor tin acetate of the oxide electron conductor material into SnO ₂, i.e. into the oxide electron conductor material, to eliminate reaction by-products, thereby forming a porous layer comprising Li ₄Ti₅O₁₂ nanoparticle aggregates covered with a uniform SnO ₂ coating, and consolidating the layer, i.e. bonding the primary nanoparticles together and adjacent aggregates together by the presence of the formed oxide electron conductor material SnO ₂, to improve the adhesion of the Li ₄Ti₅O₁₂ nanoparticle aggregates covered with SnO ₂ coating to the substrate and to perfect the recrystallization of Li ₄Ti₅O₁₂.

Example 3 production of a cell Using a porous cathode and a porous anode according to the invention

A. Preparation of Li ₃PO₄ nanoparticle suspensions

Two solutions were prepared. CH ₃COOLi,2H₂ O of 11.44 g was dissolved in 112 ml water, then 56 ml water was added to the medium with vigorous stirring to obtain solution a. 4.0584 g H ₃PO₄ was diluted in 105.6 ml water and then 45.6 ml ethanol was added to the solution to obtain a second solution, hereinafter referred to as solution B.

Solution B was then added to solution a with vigorous stirring. The resulting solution, which is very clear after the disappearance of the bubbles formed during the mixing, is added to 1.2 liters of acetone under the action of a homogenizer type UltraturraxTM to homogenize the medium. A suspension of white precipitate in the liquid phase was immediately observed.

The reaction medium was homogenized for 5 minutes and then held under magnetic stirring for 10 minutes. It was allowed to decant for 1 to 2 hours. The supernatant was discarded and the remaining suspension was centrifuged at 6000 rpm for 10 minutes. Then, 300ml of water was added to put the precipitate into suspension (using a sonotrode, magnetic stirring). 125 ml of a 100 g/l sodium tripolyphosphate solution are added to the colloidal suspension thus obtained with vigorous stirring. The suspension then becomes more stable. The suspension is then sonicated using a sonicator. The suspension was then centrifuged at 8000 rpm for 15 minutes. The pellets were then redispersed in 150 ml water. The suspension obtained was then centrifuged again at 8000 rpm for 15 minutes and the pellet obtained was redispersed in 12 mL water.

A suspension of approximately 100nm agglomerates in water formed by primary particles of Li ₃PO₄ of 10 nm was thus obtained.

B. A porous inorganic layer was produced on the preformed anode and cathode layers from the Li ₃PO₄ nanoparticle suspension described above in section a).

A thin layer of porous Li ₃PO₄ was then deposited from a suspension of previously obtained Li ₃PO₄ nanoparticles by coating on the surfaces of the preformed anode and cathode to obtain a layer with a thickness of about 3 μm. The layer was dried in air at 120 ℃ to remove any trace organic residues and calcined in air at 350 ℃ for 1 hour.

C. production of electrochemical cells

After depositing 3 μm porous Li ₃PO₄ on each electrode formed in advance (see examples 1 and 2), two subsystems were stacked to bring the Li ₃PO₄ films into contact. The stack was then hot pressed under vacuum.

For this, the stack was placed under a pressure of 1.5MPa and then dried under vacuum at 10 ^-3 bar for 30 minutes. The plates of the press were then heated to 450 ℃ at a rate of 4 ℃ per second. The stack was then hot pressed at 450 ℃ for 1 minute at a pressure of 45MPa, and the system was then cooled to ambient temperature.

After assembly, a rigid multilayer system formed from one or more assembled battery cells is obtained.

The assembly is then immersed in an electrolyte solution containing LiTFSI in 0.7MPYR14TFSI. The electrolyte immediately enters the pores by capillary action. The system was soaked for 1 minute and then the surface of the cell stack was dried with an N ₂ air knife.

Claims

1. A method for producing a porous electrode, particularly a porous electrode for use in an energy storage device or an energy generation device, the electrode being a porous layer comprising at least one electrode active material P and an oxide electronic conductor material, the electrode being binder-free, having a porosity of 25 vol% to 60 vol%, preferably 25 vol% to 50 vol%, and pores with an average diameter of less than 100 nm, the method being characterized in that it comprises:

(a) A colloidal suspension or paste comprising a substrate, at least one oxide electronic conductor material precursor, and aggregates or agglomerates of primary nanoparticles containing at least one electrode active material P, wherein the primary nanoparticles have a primary median diameter _D50 of 2 nm to 400 nm, preferably 2 nm to 100 nm, more preferably 2 nm to 60 nm, and the aggregates or agglomerates have a median diameter _D50 of 50 nm to 900 nm, preferably 100 nm to 800 nm. It should be understood that the substrate may be a substrate capable of acting as a current collector or an intermediate substrate.

(b) The one or more oxide electronic conductor material precursors provided in step (a) are mixed with the colloidal suspension or paste of an aggregate or agglomerate containing at least one electrode active material P to form a mixture.

(c) A mixture layer is formed from the mixture obtained at the end of step (b) by a method selected from the group consisting of: electrophoresis, additive manufacturing, extrusion, printing (preferably inkjet printing or flexographic printing), coating (preferably blade coating, roller coating, curtain coating, dip coating or slot extrusion coating).

(d) Drying the layer obtained in step (c) to obtain a dried layer, wherein, if necessary, the dried layer is separated from its intermediate substrate after drying step (d).

(e) Converting the one or more oxide electronic conductor material precursors into an oxide electronic conductor material, such that the dried layer contains the oxide electronic conductor material.

(f) The layer is solidified by heating and/or mechanical treatment, preferably by sintering, to obtain a porous, preferably mesoporous electrode. It should be understood that steps (e) and (f) can be performed in the same heat treatment process.

2. The method for manufacturing a porous electrode according to claim 1, characterized in that step (b) is carried out by contacting a colloidal suspension or paste of an aggregate or cluster of primary nanoparticles containing at least one electrode active material P provided in step (a) with a liquid phase containing at least one precursor of the oxide electronic conductor material, and wherein the conversion of the one or more oxide electronic conductor material precursors to the oxide electronic conductor material during step (e) is carried out by heat treatment such as calcination, preferably in air or an oxidizing atmosphere.

3. The method for manufacturing a porous electrode according to claim 1 or 2, characterized in that, after step (f), the pores of the porous electrode are impregnated with an electrolyte, preferably with a phase containing lithium ions, sodium ions, or potassium ions, wherein the electrolyte is selected from:

- An electrolyte consisting of at least one aprotic solvent and at least one lithium, sodium, or potassium salt; - An electrolyte consisting of at least one ionic liquid and at least one lithium, sodium, or potassium salt; - A mixture of at least one aprotic solvent, at least one ionic liquid, and at least one lithium, sodium, or potassium salt; - An ionic liquid polymer; - A polymeric ionic conductor made by adding at least one lithium, sodium, or potassium salt; and - A polymeric ionic conductor made by adding a liquid electrolyte to a polymeric phase or porous structure of a porous electrode, or by using an ionic conductor polymer, wherein the ionic conductor polymer is preferably selected from polyethylene oxide (PEO), polyacrylonitrile (PAN), poly(methyl methacrylate) (PMMA), poly(propylene carbonate) (PPC), poly(carbonate) (PEC), poly(ethylene carbonate) (PVC), polyvinylidene fluoride (PVDF), polypropylene glycol (PPG), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polydimethylsiloxane (PDMS), poly(ε-caprolactone) (PCL), and poly(trimethylene carbonate) (PTMC).

4. The method for preparing a porous electrode according to any one of claims 1 to 3, characterized in that the one or more oxide electronic conductor material precursors are selected from organic salts containing one or more metal elements, wherein the metal elements are capable of forming oxide electronic conductors after heat treatment such as calcination, and characterized in that the conversion to an electronic conductor material is a heat treatment, such as calcination, preferably carried out in air or an oxidizing atmosphere, and these organic salts are preferably selected from:

- An alkoxide of at least one metallic element capable of forming an oxide electronic conductor after heat treatment, preferably in air or an oxidizing atmosphere, such as calcination; - A nitrate of at least one metallic element capable of forming an oxide electronic conductor after heat treatment, preferably in air or an oxidizing atmosphere, such as calcination; - An oxalate of at least one metallic element capable of forming an oxide electronic conductor after heat treatment, preferably in air or an oxidizing atmosphere, such as calcination; and - An acetate of at least one metallic element capable of forming an oxide electronic conductor after heat treatment, preferably in air or an oxidizing atmosphere, such as calcination.

- and/or preferably, the metallic element is selected from tin, zinc, indium, gallium, molybdenum, or a mixture of two, three, four, or five of these elements.

5. The method for producing a porous electrode according to any one of claims 1 to 4, characterized in that the oxide electronic conductor material is selected from: - tin oxide (SnO ₂ ), aluminum-doped zinc oxide (ZnO:Al), preferably having a molar ratio of 1:0.015 to 1:0.05 (Zn:Al), indium oxide (In _2O ₃ ), gallium oxide (Ga _2O ₃ ), molybdenum oxide (MoO ₃ ), strontium molybdenum oxide (SrMoO ₃ ), mixtures of two of these oxides, such as indium tin oxide corresponding to a mixture of indium oxide (In _2O ₃ ) and tin oxide (SnO ₂ ), mixtures of three of these oxides, mixtures of four of these oxides, mixtures of five of these oxides, or mixtures of six of these oxides.

- A zinc oxide-based doped oxide, preferably doped with gallium (Ga) and/or aluminum (Al) and/or boron (B) and/or beryllium (Be), and/or chromium (Cr) and/or cerium (Ce) and/or titanium (Ti) and/or indium (In) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or manganese (Mn) and/or germanium (Ge) and/or molybdenum (Mo).

- Indium oxide-based doped oxides, preferably doped with tin (Sn) and/or gallium (Ga) and/or chromium (Cr) and/or cerium (Ce) and/or titanium (Ti) and/or indium (In) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or manganese (Mn) and/or germanium (Ge) and/or molybdenum (Mo), - doped tin oxides, preferably doped with arsenic (As) and/or fluorine (F) and/or nitrogen (N) and/or niobium (Nb) and/or phosphorus (P) and/or antimony (Sb) and/or aluminum (Al) and/or titanium (Ti) and/or gallium (Ga) and/or chromium (Cr) and/or cerium (Ce) and/or indium (In) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or manganese (Mn) and/or germanium (Ge) and/or molybdenum (Mo), - based on oxide Molybdenum-doped oxides, preferably doped with lithium (Li) and/or sodium (Na) and/or potassium (K) and/or beryllium (Be) and/or magnesium (Mg) and/or calcium (Ca) and/or scandium (Sc) and/or titanium (Ti) and/or vanadium (V) and/or chromium (Cr) and/or manganese (Mn) and/or iron (Fe) and/or cobalt (Co) and/or nickel (Ni) and/or copper (Cu) and/or zinc (Z). n) and/or gallium (Ga) and/or germanium (Ge) and/or arsenic (As) and/or rubidium (Rb) and/or cesium (Cs) and/or yttrium (Y) and/or zirconium (Zr), and/or strontium (Sr) and/or niobium (Nb) and/or tritium (T) and/or rhenium and/or iridium (Ir) and/or platinum (Pt) and/or gold (Au) and/or mercury (Hg) and/or lead (Pb) and/or bismuth (Bi).

6. The method for manufacturing a porous electrode according to any one of claims 1 to 5, characterized in that the porous electrode obtained at the end of step (f) has a specific surface area of 10 ^m² /g to 500 ^m² /g and/or a thickness of 2 µm to 400 µm, preferably 2 µm to 300 µm, more preferably 3 µm to 200 µm.

7. The method for producing a porous electrode according to any one of claims 1 to 5, characterized in that the porous electrode obtained at the end of step (f) has a specific surface area of 10 ^m² /g to 500 ^m² /g; and/or

When the substrate is a substrate capable of acting as a current collector, it has a thickness of 2 μm to 20 μm, and/or

When the substrate is an intermediate substrate, it has a thickness of 25 μm to 500 μm, preferably 50 μm to 400 μm.

8. The method for producing a porous electrode according to any one of claims 1 to 5, characterized in that, when the substrate is an intermediate substrate, after drying the layer, the layer is separated from the intermediate substrate in step (d) to form a porous plate.

9. The method for producing a porous electrode according to any one of claims 1 to 8, characterized in that the colloidal suspension or paste provided in step (a) comprises an organic additive, such as a ligand, stabilizer, binder or residual organic solvent, and the dried layer obtained at the end of step (d) according to any one of claims 1 to 7 or the porous plate according to claim 8 is subjected to heat treatment, preferably in an oxidizing atmosphere, and it should be understood that the heat treatment and steps (e) and/or (f) can be performed in the same heat treatment step.

10. The method for producing a porous electrode according to any one of claims 1 to 9, wherein the electrode active material P is selected from the group (A) of the following:

- Oxides _LiMn₂O₄ , _Li₁+ _xMn₂- _xO₄ _, where 0 < x <0.15; LiCoO₂, _LiNiO₂ , _{LiMn₁.5Ni₀.5O₄} , _{LiMn₁.5Ni₀.5} _- _xX₀O₄ , where X is selected from Al, Fe, Cr, Co, _Rh , _Nd , other rare _earth elements such as Sc, Y, Lu, La, Ce, Pr, Pm, Sm, Eu, Gd, _Tb , Dy, Ho, Er, Tm, Yb, and where 0 < x <_0.1; LiMn₂ _- _xM₀O₄ , where M = Er, Dy, Gd, Tb, Yb, Al, Y, Ni, Co, Ti, Sn, As, Mg, or mixtures of these elements, and where 0 < x <0.4; _LiFeO₂ , LiMn₁ _/ ₃ Ni _1/3 Co _1/3 O ₂ , LiNi _0.8 Co _0.15 Al _0.05 O ₂ , LiAl _x Mn _2-x O ₄ , where 0 ≤ x < 0.15, LiNi _1/x Co _1/y Mn _1/z O ₂ , where x+y+z =10;

- Li _x _My O ₂ , where 0.6≤y≤0.85; 0≤x+y≤2; and M is selected from Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ru, Sn and Sb, or mixtures of these elements; Li _1.20 Nb _0.20 Mn _0.60 O ₂ ;

- Li _1+x Nb _y Me _z A _p O ₂ , wherein Me is at least one transition metal selected from the following: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, and wherein 0.6 < x <1; 0 < y <0.5; 0.25 ≤ z <1; wherein A ≠ Me and A ≠ Nb, and 0 ≤ p ≤ 0.2;

- Li _x Nb _ya N _a M _zb P _b O _2-c F _c , where 1.2 < x ≤ 1.75; 0 ≤ y <0.55; 0.1 < z <1; 0 ≤ a <0.5; 0 ≤ b <1; 0 ≤ c <0.8; and where M, N and P are each at least one element selected from the group consisting of: Ti, Ta, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Al, Zr, Y, Mo, Ru, Rh, Ce and Sb;

- Li _1.25 Nb _0.25 Mn _0.50 O ₂ ; Li _1.3 Nb _0.3 Mn _0.40 O ₂ ; Li _1.3 Nb _0.3 Fe _0.40 O ₂ ; Li _1.3 Nb _0.43 Ni _0.27 O ₂ ; Li _1.3 Nb _0.43 Co _0.27 O ₂ ;Li _1.4 Nb _0.2 Mn _0.53 O ₂ ;

- Li _x Ni _0.2 Mn _0.6 O _y , where 0.00≤x≤1.52; 1.07≤y<2.4; Li _1.2 Ni _0.2 Mn _0.6 O ₂ ;

- LiNi _x Co _y Mn _1-xy O ₂ , where 0 ≤ x and y ≤ 0.5; LiNi _x Ce _z Co _y Mn _1-xy O ₂ , where 0 ≤ x and y ≤ 0.5 and 0 ≤ z;

- Phosphates _of the formula _LiFePO4 , _LiMnPO4 , _LiCoPO4 , _LiNiPO4 , _Li3V2 ( _PO4 ) ₃ _, _Li2MPO4F , where M = Fe, Co, Ni or a mixture of these different elements; _LiMPO4F , where M = V, Fe, T or a mixture of these different elements; phosphates of the formula _LiMM'PO4 , where M and M' (M ≠ M') are selected from Fe, Mn, Ni, Co, V, for example _LiFexCo1 _-xPO4 _, and where 0 < x <1;

- Fe _0.9 Co _0.1 OF; FeF ₃ ; LiMSO ₄ F, where M = Fe, Co, Ni, Mn, Zn, Mg;

- Titanium oxysulfide (TiO _y S _z , where z = 2-y and 0.3 ≤ y ≤ 1), tungsten oxysulfide (WO _y S _z , where 0.6 < y < 3 and 0.1 < z < 2), CuS, CuS _2 , Li _x V ₂ O ₅ , where 0 < x ≤ 2, Li _x V _3 O_8 , where 0 < x ≤ 1.7, Li _x TiS _2 , where 0 < x ≤ 1, lithium titanium oxysulfide Li _x TiO _y S _z , where z = 2-y, 0.3 ≤ y ≤ 1 and 0 < x ≤ 1, Li _x _{WOy} _Sz, where z = 2-y, 0.3 ≤ y ≤ 1 and 0 < x ≤ 1, Li _x CuS, where 0 < x ≤ 1, Li _x CuS ₂ , where 0 < x ≤ 1;

Alternatively, choose from the following groups (B):

Transition metal oxides:

○ Na _x MO _2+z , where M is selected from Mg, Ca, Li, Mn, Ni, Co, Cr, Sc, Te, where z≤0.3 and 0<x≤1, preferably 0<x<0.44 or 0.44≤x≤0.67 or 0.67<x≤1;

○ Na _x M _u/2 M' _v/2 O _2+z where u+v=2 and M and M' are selected from Mg, Ca, Li, Mn, Ni, Co, Cr, Sc, Te, where z≤0.3 and 0<x≤1, preferably 0<x<0.44 or 0.44≤x≤0.67 or 0.67<x≤1;

○ Na _x M _u/3 M' _v/3 M'' _w/3 O _2+z where u+v+w=3 and M, M', M'' are selected from Mg, Ca, Li, Mn, Ni, Co, Cr, Sc, Te, where z≤0.3 and 0<x≤1, preferably 0<x<0.44 or 0.44≤x≤0.67 or 0.67<x≤1;

○ Na _x Mn _y Ni _z Fe _0.1 Mg _0.1 O ₂ , where 0.67≤x≤1.0; 0.5≤y≤0.7 and 0.1≤z≤0.3;

- Prussian blue and/or Prussian blue analogues, abbreviated as PBA:

○ Na _x M ¹ [ M ² '(CN) ₆ ] _y .nH ₂ O, where M ¹ is a transition metal or a transition metal alloy, M ² ' is a transition metal, and the transition metal and the transition metal alloy are selected from Fe, Ni, Co and Mn, where 0≤x≤2; y≤1 and 0≤n≤12;

- Polyanionic compounds:

○ Na _x M ₂ (XO ₄ ) ₃ , where 0 < x ≤ 4, M = V, Fe, Cr, Mn, Co, Ni or Sc and X = P, S, As, Si, Mo or W, for example Na ₃ V ₂ (PO ₄ ) ₃ ;

○ Na _x M ₃ (XO ₄ ) ₂ (X ₂ O ₇ ), where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ Na _x M(X ₂ O ₇ ), where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ Na _x M ₂ (XO ₄ ) ₂ F ₃ , where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ Na _x M ₂ (XO ₄ ) ₂ F _3-y O _y , where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and 0.07≤y≤0.12 and X=P,S,As,Si,Mo orW;

○ Na _x M ₂ O ₂ (XO ₄ ) ₂ F, where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ Na _x MXO ₄ , where 0 < x ≤ 4, M = V, Fe, Cr, Mn, Co, Ni or Sc and X = P, S, As, Si, Mo or W;

Alternatively, choose from the following groups (C):

-Transition metal oxides:

○ K _x MO _2+z , where M is selected from Mg, Ca, Li, Mn, Ni, Co, Cr, Sc, Te, where z≤0.3 and 0<x≤1, preferably 0<x<0.44 or 0.44≤x≤0.67 or 0.67<x≤1;

○ K _x M _u/2 M' _v/2 O _2+z , where u+v=2 and M and M' are selected from Mg, Ca, Li, Mn, Ni, Co, Cr, Sc, Te, where z≤0.3 and 0<x≤1, preferably 0<x<0.44 or 0.44≤x≤0.67 or 0.67<x≤1;

○ K _x M _u/3 M' _v/3 M'' _w/3 O _2+z , where u+v+w=3 and M, M', M'' are selected from Mg, Ca, Li, Mn, Ni, Co, Cr, Sc, Te, where z≤0.3 and 0<x≤1, preferably 0<x<0.44 or 0.44≤x≤0.67 or 0.67<x≤1;

○ K _x Mn _y Ni _z Fe _0.1 Mg _0.1 O ₂ , where 0.67≤x≤1.0; 0.5≤y≤0.7 and 0.1≤z≤0.3;

- Prussian blue and/or Prussian blue analogues, abbreviated as PBA:

○ L _x M ¹ [ M ² '(CN) ₆ ] _y .nH ₂ O, M ¹ is a transition metal or a transition metal alloy, M ² ' is a transition metal, wherein the transition metal and the transition metal alloy are selected from Fe, Ni, Co and Mn, wherein 0≤x≤2; y≤1 and 0≤n≤12;

- Polyanionic compounds:

○ K _x M ₂ (XO ₄ ) ₃ , where 0 < x ≤ 4, M = V, Fe, Cr, Mn, Co, Ni or Sc and X = P, S, As, Si, Mo or W, for example Na ₃ V ₂ (PO ₄ ) ₃ ;

○ K _x M ₃ (XO ₄ ) ₂ (X ₂ O ₇ ), where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ K _x M(X ₂ O ₇ ), where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ K _x M ₂ (XO ₄ ) ₂ F ₃ , where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ K _x M ₂ (XO ₄ ) ₂ F _3-y O _y , where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and 0.07≤y≤0.12 and X=P,S,As,Si,Mo orW;

○ K _x M ₂ O ₂ (XO ₄ ) ₂ F, where 0<x≤4, M=V,Fe,Cr,Mn,Co,Ni orSc and X=P,S,As,Si,Mo orW;

○ K _x MXO ₄ , where 0 < x ≤ 4, M = V, Fe, Cr, Mn, Co, Ni or Sc and X = P, S, As, Si, Mo or W.

11. The method for producing a porous electrode according to any one of claims 1 to 9, wherein the electrode active material P is selected from the group (D) of the following:

Li ₄ Ti ₅ O ₁₂ , Li ₄ Ti _5-x M _x O ₁₂ where M=V, Zr, Hf, Nb, Ta and 0≤x≤0.25;

Niobium oxides and mixed oxides of niobium with titanium, germanium, cerium or tungsten, preferably selected from the group consisting of:

Nb ₂ O _5±δ , Nb ₁₂ WO _33±δ , Nb ₁₄ W ₃ O _44±δ , Nb ₁₈ W ₁₆ O _93±δ , Nb ₁₆ W ₅ O _55±δ , where 0 ≤ δ ≤ 2, LiNbO ₃ ,

_TiNb₂O₇ _±δ , Li _wTiNb₂O₇ , where _w≥0 , Ti ¹ _-x _M₁x Nb₂ _-y M₂y ^O₇ _±δ or Li _wTi _1-x _M₁x ^Nb₂ _-y _M₂y ^O₇ _±δ , where ^M₁ _and ^M₂ are each at least one element selected from the group consisting of: Nb, V, Ta, _Fe , Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs and Sn, ^M₁ and ^M₂ may be the same as or different from each other, and where 0≤w≤5 and 0≤x≤1 and 0≤y≤2 and 0≤δ≤0.3;

La _x Ti _1-2x Nb _2+x O ₇ , where 0<x<0.5;

M _x Ti _1-2x Nb _2+x O _7±δ , where M is an element with an oxidation state of +III. More specifically, M is at least one element selected from the group consisting of Fe, Ga, Mo, Al, and B, where 0 < x ≤ 0.20 and -0.3 ≤ δ ≤ 0.3; Ga _0.10 Ti _0.80 Nb _2.10 O ₇ ; Fe _0.10 Ti _0.80 Nb _2.10 O ₇ ;

M _x Ti _2-2x Nb _10+x O _29±δ where M is an element with an oxidation state of +III, and more specifically, M is at least one element selected from the group consisting of Fe, Ga, Mo, Al, and B, wherein 0 < x ≤ 0.40 and -0.3 ≤ δ ≤ 0.3;

Ti _1-x M ¹ _x Nb _2-y M ² _y O _7-z M ³ _z or Li _w Ti _1-x M ¹ _x Nb _2-y M ² _y O _7-z M ³ _z where

- ^M1 and ^M2 are each at least one element selected from the group consisting of: Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, and Sn.

^M1 and ^M2 can be the same as or different from each other.

- ^M3 is at least one halogen.

- where 0≤w≤5, 0≤x≤1, 0≤y≤2, and z≤0.3;

_{TiNb₂O₇₇} _-z _M₃₇ ^or _{Li₂wTiNb₂O₇₇} _-z _M₃₇ ^, wherein ^M₃ is at least one halogen, preferably selected from F, Cl, Br, I or a mixture _thereof , and 0 ≤ z ≤ 0.3 and 0 ≤ w ≤ 5;

Ti _1-x Ge _x Nb _2-y M ¹ _y O _7±z , Li _w Ti _1-x Ge _x Nb _2-y M ¹ _y O _7±z , Ti _1-x Ce _x Nb _2-y M ¹ _y O _7±z , Li _w Ti _1-x Ce _x Nb _2- _y M ¹ _y O _7±z , where

- ^M1 is at least one element selected from the group consisting of: Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs and Sn;

- 0≤w≤5 and 0≤x≤1 and 0≤y≤2 and z≤0.3;

Ti _1-x Ge _x Nb _2-y M ¹ _y O _7-z M ² _z 、Li _w _Ti _1-x Ge _x Nb _2-y M ¹ _y O _7-z M ² _z 、Ti _1-x _Ce _x Nb ₂ _-y _M ¹ _y O ⁷ _- _z M ² _z 、Li w _Ti _1-x ^Ce _z , where

- ^M1 and ^M2 are each at least one element selected from the group consisting of: Nb, V, Ta, Fe, Co, Ti, Bi, Sb, As, P, Cr, Mo, W, B, Na, Mg, Ca, Ba, Pb, Al, Zr, Si, Sr, K, Cs, Ce, and Sn.

^M1 and ^M2 can be the same as or different from each other.

- where 0≤w≤5, 0≤x≤1, 0≤y≤2, and z≤0.3;

_TiO₂ ; _TiO₂xNy , where x < ₂ and 0 < y <0.2;

LiSiTON, a tin and silicon-based oxide nitride, and more particularly SiSn _0.87 O _1.20 N _1.72 and its lithiated form;

Nitrides and _MOxNy _type oxynitrides, wherein M is at least one element selected from the following: Ge, Si, Sn, Zn, Co, Ni, Cu, Fe or one or more of these elements, wherein x ≥ 0 and y ≥ 0.3;

Li _3-X M _x N, where M is at least one element selected from Cu, Ni, Co, or a mixture of one or more of these elements and 0 ≤ x ≤ 1;

Li _3-X M _x N, where M is cobalt (Co) and 0≤x≤0.5; Li _3-X M _x N, where M is nickel (Ni) and 0≤x≤0.6; Li _3- _X M _x N, where M is copper (Cu) and 0≤x≤0.3;

Lithium-ionized iron phosphate with the typical molecular formula _LiFePO4 ;

Mixed silicon-tin oxynitrides with the typical molecular formula Si _a Sn _b O _y N _z , where a>0, b>0, a+b≤2, 0<y≤4, 0<z≤3, are also called SiTON, specifically SiSn _0.87 O _1.2 N _1.72 ; and oxynitride carbides with the typical molecular formula Si _a Sn _b C _c O _y N _z , where a>0, b>0, a+b≤2, 0<c<10, 0<y<24, 0<z<17;

Si _x N _y type nitrides, particularly where x = 3 and y = 4; Sn _x N_y , particularly where x = 3 and y = 4; Zn _x N _y , particularly where x = 3 and y = 2; Li _{3-x} M _x N, where for M = Co, 0 ≤ x ≤ 0.5, for M = Ni, 0 ≤ x ≤ 0.6, for M = Cu, 0 ≤ x ≤ 0.3; Si _{3-x} M _x N ₄ , where M = Co or Fe and 0 ≤ x ≤ 3.

Oxides _SnO₂ , _SnO , _Li₂SnO₃ , _SnSiO₃ , _LiₓSiO₂y , _where _x > ₌ 0 and 2> _y >0, _{Li₄Ti₅O₁₂} , _TiNb₂O₇ _, _Co₃O₄ , _{SnB₀.₆P₀.₄O₂.₉} _and _TiO₂ _,

Si, Sn, _SiO2 , _SnO2 , SiN, SnN and their mixtures,

The _composite oxide _TiNb₂O₇ contains 0% to 10% carbon, preferably selected from graphene and carbon nanotubes.

Or choose from the following groups (E):

- Alloys based on Si, Ge, Sn, Sb, Bi, or P, and alloys of these different compounds.

- Maicoenes are a class of two-dimensional materials with a stoichiometry of Mn ₊₁ _XnTx _type , where M is a transition metal, preferably selected from Sc, Ti, V, Cr, Y, Zr, Nb, Mo, Hf, Ta, W, and X is selected from C and/or N, and T is a surface terminator selected from F, Cl, I, Br, O, S, Se, Te, OH, _NH2 , 1≤n≤4

-Convert anode materials, for example

○ _G2Ti3O7 , _G4Ti5O12 _, _GTi2 ( _PO4 ) ₃ type _oxides , _where _G is Na or K.

○ The oxides, sulfides, selenides, and phosphides of the following elements and their alloys: Si, Ge, Sn, Sb, Bi.

12. A porous electrode that can be obtained by the method according to any one of claims 1 to 11.

13. A method for manufacturing a porous electrode using any one of claims 1 to 11 or a method for manufacturing an energy storage device or a production device using a porous electrode according to claim 12.

14. The method according to claim 13, wherein the energy storage device or energy production device is selected from the group consisting of: capacitors, supercapacitors, hybrid supercapacitors, such as lithium-ion hybrid supercapacitors, sodium-ion hybrid supercapacitors, potassium-ion hybrid supercapacitors, photovoltaic cells, photoelectrochemical cells, or batteries such as lithium-ion batteries, sodium-ion batteries, or potassium-ion batteries.

15. The method of claim 14, wherein the apparatus is a lithium-ion battery, and the method of preparing a porous electrode according to claim 10 is implemented to produce a cathode using an electrode active material P selected from group (A), or the method of claim 11 is implemented to produce an anode using an electrode active material P selected from group (D).

16. The method of claim 14, wherein the apparatus is a sodium-ion battery, and the method of preparing a porous electrode according to claim 10 is implemented to produce a cathode using an electrode active material P selected from group (B), or the method of claim 11 is implemented to produce an anode using an electrode active material P selected from group (E).

17. The method of claim 14, wherein the device is a potassium-ion battery, and the method of preparing a porous electrode according to claim 10 is implemented to produce a cathode using an electrode active material P selected from group (C), or the method of claim 11 is implemented to produce an anode using an electrode active material P selected from group (E).

18. The method according to any one of claims 13 to 17, wherein the device is a lithium-ion battery, a sodium-ion battery, or a potassium-ion battery, and the porous electrode is impregnated with an electrolyte, preferably with a phase carrying lithium ions, sodium ions, or potassium ions, wherein the electrolyte is selected from the group consisting of:

- An electrolyte consisting of at least one aprotic solvent and at least one lithium, sodium, or potassium salt; - An electrolyte consisting of at least one ionic liquid and at least one lithium, sodium, or potassium salt; - A mixture of at least one aprotic solvent, at least one ionic liquid, and at least one lithium, sodium, or potassium salt; - An ionic liquid polymer; - A polymeric ionic conductor made by adding at least one lithium, sodium, or potassium salt; and - A polymeric ionic conductor made by adding a liquid electrolyte to a polymeric phase or porous structure of a porous electrode, or by using an ionic conductor polymer, preferably selected from polyethylene oxide (PEO), polyacrylonitrile (PAN), poly(methyl methacrylate) (PMMA), poly(propylene carbonate) (PPC), poly(carbonate) (PEC), poly(ethylene carbonate) (PVC), polyvinylidene fluoride (PVDF), polypropylene glycol (PPG), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), polydimethylsiloxane (PDMS), poly(ε-caprolactone) (PCL), and poly(trimethylene carbonate) (PTMC).

19. An energy storage device or an energy generation device that can be obtained by the method according to any one of claims 13 to 18.

20. The energy storage device or energy production device according to claim 19, characterized in that it is a capacitor, a supercapacitor, a hybrid supercapacitor, such as a lithium-ion hybrid supercapacitor, a sodium-ion hybrid supercapacitor, a potassium-ion hybrid supercapacitor, a photovoltaic cell, a photoelectrochemical cell, or a battery such as a lithium-ion battery, a sodium-ion battery, or a potassium-ion battery.