CN105576287B - Solid electrolyte lithium ion battery and preparation method thereof of the integration without interface - Google Patents

Abstract

The present invention provides a kind of integrated solid electrolyte lithium ion batteries without interface, binders for electrodes in its solid electrolyte lithium ion battery contains same material component with solid electrolyte material, particularly preferably contains fluorine-containing sulfimide moiety polymeric material components of the same race.There is good compatibility between electrolyte and electrode material in the integration lithium ion battery, there is lower lithium ion dissociation energy when preferably comprising fluorine-containing sulfimide moiety, to improve conductivity of the lithium ion in charge and discharge process, reduce the internal resistance of cell.In addition, the invention also provides the high integrated battery preparation methods of two kinds of simple production process, the electrode active material layers uniformity, it is with a wide range of applications in solid electrolyte field of lithium ion battery, especially high magnification, high-capacity dynamical solid electrolyte field of lithium ion battery.

Description

Integrated non-interface solid-state electrolyte lithium-ion battery and preparation method thereof

technical field

The invention belongs to the field of lithium-ion batteries and their manufacture, and in particular relates to an integrated interfaceless solid-state electrolyte lithium-ion battery and a preparation method thereof.

Background technique

At present, traditional lithium-ion batteries usually use toxic and leaky organic liquid electrolytes, so there are certain safety hazards and environmental pollution problems. The polymer lithium battery that appeared in the 1990s uses a solid or gel polymer electrolyte, so it has higher safety, stability and better environmental friendliness. In addition, polymer lithium-ion batteries also have the advantages of flexible shaping, high specific energy, wide electrochemical stability window, less capacity loss, and high volume utilization. They are the main development direction of lithium-ion batteries in the future.

However, compared with the liquid electrolyte that can fully soak into the electrode pole piece, the polymer electrolyte has solid properties, and the conductivity of lithium ions in the solid electrolyte is much lower than that of the liquid electrolyte; and between the polymer electrolyte and the electrode pole piece There is a problem of poor contact tightness. In addition, since the passivation film of the solid electrolyte is relatively stable, if the solid electrolyte used is poorly compatible with the electrode sheet, the passivation film will grow with time, thereby increasing the internal resistance of the battery. Therefore, improving the compatibility between electrode materials and electrolytes is a key technical issue that needs to be solved urgently in the application and development of solid-state electrolyte lithium batteries.

In response to this technical bottleneck, researchers have tried to simplify the internal structure of lithium-ion batteries by constructing an integrated structure, improve the contact state between different components, and then improve the compatibility between battery components and reduce the internal resistance of lithium-ion batteries. to achieve better energy storage performance. In the Chinese invention patent with the publication number CN1219779A, the researchers poured the polymer electrolyte solution into the active material layer containing the active material and binder of the positive and negative electrodes, so that the polymer electrolyte penetrated into the positive and negative active material layers. ; Then the solvent is evaporated, and the positive and negative electrode sheets containing the electrolyte face each other; finally, the two pole sheets are fused together by an external hot melt agent to form a flat solid electrolyte polymer lithium battery. The method improves the contact between the electrolyte and the active material through the penetration of the electrolyte in the electrode active material layer, reduces the internal resistance of the battery, and obtains a lithium ion battery with excellent contact performance and high discharge output. The Chinese invention patent with the publication number CN103413966A has improved the compatibility between the electrode material and the inorganic diaphragm layer. The researchers sprayed the inorganic ceramic particles soaked in the electrolyte on the electrode pole piece, dried and rolled to obtain a lithium-ion battery. Use a membrane electrode. This kind of membrane electrode sheet realizes the integration of the positive and negative electrode sheets and the separator, simplifies the structure of the lithium-ion battery, and the obtained lithium battery shows better high-temperature stability than the traditional structure of the lithium-ion battery.

However, in order to further reduce the internal resistance of the battery and obtain a solid-state electrolyte lithium-ion battery with excellent contact performance and high discharge output performance, it is still necessary to further improve the compatible contact between the electrolyte and the electrode active material, and strive to achieve an integrated solid-state electrolyte with no interface. Lithium Ion Battery.

Contents of the invention

The technical purpose of the present invention is to provide a solid-state electrolyte lithium-ion battery with the advantages of low battery internal resistance, excellent contact performance and high discharge specific capacity in view of the technical status quo of the above-mentioned solid-state electrolyte lithium-ion battery. Interfacial solid electrolyte lithium-ion batteries.

The technical scheme adopted in the present invention is: an integrated non-interface solid electrolyte lithium ion battery, comprising a positive electrode current collector, a positive electrode active material layer on the positive electrode current collector, a negative electrode current collector, a negative electrode active material layer on the negative electrode current collector, and Solid state electrolyte, the positive electrode active material layer includes a positive electrode active material, a conductive agent and a binder, and the negative electrode active material layer includes a negative electrode active material, a conductive agent and a binder; it is characterized in that: the bonding The agent contains the same material components as the solid electrolyte, that is, the following cases are included:

(1) When the binder and the solid electrolyte are both a single material, the binder material is the same as the solid electrolyte material;

(2) When the binder is a combined material and the solid electrolyte is a single material, the solid electrolyte material is one of the binder materials;

(3) When the binder is a composite material and the solid electrolyte is a composite material, the same material components exist in the binder and the solid electrolyte.

That is to say, the electrode binder and the solid electrolyte material in the solid electrolyte lithium ion battery of the present invention are selected from the same material, or the same material components exist in the two, which is conducive to improving the phase between the electrode and the electrolyte of the battery. Capacitance, improve the conductivity of lithium ions in the process of charging and discharging, reduce the internal resistance of the battery, and can simplify the battery production process and improve the uniformity of the electrode material layer. Therefore, in the field of solid electrolyte lithium ion batteries, especially high rate, large It has broad application prospects in the field of capacity power solid-state electrolyte lithium-ion batteries.

In the present invention, the solid electrolyte material preferably includes a polymer material with high ion conductivity and high binding property. Preferably, the solid-state electrolyte is a fluorine-containing sulfonimide-based polymer material, or a material containing a fluorine-containing sulfonimide-based polymer component, and both the binder and the solid-state electrolyte contain Fluorosulfonimide polymer components, that is, include the following cases:

(1) When the binder material and the solid electrolyte material are both a single material, the binder material and the solid electrolyte material are the same fluorine-containing sulfonimide-based polymer;

(2) When the binder material is a combination material and the solid electrolyte material is a single material, the solid electrolyte material is a fluorine-containing sulfonimide-based polymer, and the binder material contains the same fluorine-containing sulfonyl imide Amine-based polymer components;

(3) When the binder material is a composite material and the solid electrolyte material is also a composite material, the same fluorine-containing sulfonimide-based polymer component exists in the binder material and the solid electrolyte material.

The fluorine-containing sulfonimide-based polymer material is a polymer whose main chain or side chain contains both fluorine atom groups and sulfonimide groups and its inorganic nanocomposite materials, including poly(5-sulfonyl chloride- 3-Oxa) Lithium salt of perfluorosulfonamide, polyether ether ketone resin with fluorine-containing sulfonimide group as the side chain, fluorine-containing sulfonimide materials such as fluorine-containing sulfonimide-based polymer modified graphene one or a mixture of several.

The positive electrode active material is not limited, including oxides containing lithium and transition metals such as lithium iron oxide, lithium cobalt oxide, lithium nickel oxide, such as lithium cobaltate, lithium manganate, lithium nickel manganate and other compound materials , can also include sulfur-based cathode materials.

The negative electrode active material is not limited, including graphite, graphene, carbon nanotubes and other carbon materials and their composite materials, lithium metal, lithium-containing transition metal nitrides, silicon oxide and silicon-based composite materials, sulfur-containing inorganic compounds, etc. .

The material of the conductive agent is not limited, including acetylene black, Super P, carbon black and the like.

The positive current collector is not limited, and may be made of aluminum foil and other materials.

The negative electrode current collector is not limited, it can be copper foil and other materials.

The present invention also provides two methods for preparing the above-mentioned integrated non-interface solid electrolyte lithium-ion battery, one of which is shown in Figure 1, including the following steps:

(1) Mix the positive electrode active material, conductive agent, binder and the first solvent uniformly to prepare the positive electrode active slurry; mix the negative electrode active material, conductive agent, binder and the second solvent uniformly to obtain the negative active electrode slurry;

(2) Coating the positive electrode active slurry on the surface of the positive electrode collector to prepare the positive electrode sheet 1; coating the negative electrode active slurry on the surface of the negative electrode collector to prepare the negative electrode sheet 2;

(3) dissolving the solid electrolyte material in a third solvent to obtain an electrolyte solution;

(4) The electrolytic solution is coated on the surface of the positive electrode sheet and the surface of the negative electrode sheet respectively, and the electrolyte film 3 is formed after drying to remove the third solvent. In contrast, molding is then used to form a whole, and finally an integrated lithium-ion battery is made through subsequent processes such as slicing, winding, welding tabs, and packaging.

The first solvent is not limited, and includes water, methanol, ethanol, n-propanol, isopropanol, n-butanol, N-methylpyrrolidone, etc. or a mixture of two or more materials mixed in any proportion.

The second solvent is not limited, and includes water, methanol, ethanol, n-propanol, isopropanol, n-butanol, N-methylpyrrolidone, etc. or a mixture of two or more materials mixed in any proportion.

The third solvent is not limited, including ethylene carbonate (EC), propylene carbonate (CP), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), Y- Butyl propyl ester (GBL), methyl formate (MF), methyl acetate (MVA), tetrahydrofuran (THF), l,2-dimethoxyethane (DME), etc. a mixture of solvents.

In the step (2), the coating method is not limited, including spin coating, casting, printing and other methods.

Preferably, the thickness of the positive electrode sheet is 10-300 μm±10 μm.

Preferably, the thickness of the negative electrode sheet is 10-300 μm±10 μm.

Preferably, the thickness of the electrolyte layer is 50-200 μm.

The above preparation method is simple and feasible, and the compatibility between the electrolyte and the active material layer is improved through the penetration of the electrolyte in the electrode active material layer, thereby reducing the internal resistance of the battery and obtaining a lithium ion battery with high specific capacity.

However, in the above preparation method, the problems of uneven coating and poor material contact are prone to occur during the coating of electrode active particles and electrolyte coating. In addition, in the process of pressing the electrode pole piece and the solid electrolyte membrane together, gaps or mold deformation are likely to occur at the interface of the electrolyte membrane, which will affect the performance of the battery due to the uneven structure of the solid electrolyte material.

For this reason, the present invention also provides another kind of improved preparation method, spraying method, as shown in Figure 2, comprises the steps:

(1) Mix the positive electrode active material, conductive agent, binder and the first solvent uniformly to prepare the positive electrode active slurry; mix the negative electrode active material, conductive agent, binder and the second solvent uniformly to obtain the negative active electrode slurry;

(2) Spraying the positive electrode active slurry and the negative electrode active slurry on both sides of the solid electrolyte membrane;

(3) The positive electrode current collector is arranged on the side of the electrolyte membrane coated with the positive electrode active slurry, and the negative electrode current collector is arranged on the side of the electrolyte membrane coated with the negative electrode active slurry, and then pressed into one body by rolling.

The first solvent is not limited, and includes water, methanol, ethanol, n-propanol, isopropanol, n-butanol, N-methylpyrrolidone, etc. or a mixture of two or more materials mixed in any proportion.

The second solvent is not limited, and includes water, methanol, ethanol, n-propanol, isopropanol, n-butanol, N-methylpyrrolidone, or a mixture of two materials mixed in any proportion.

In the above method, after step (3), follow-up processes such as slicing, winding, welding tabs, and packaging are carried out.

The above method has the following advantages:

(1) Spraying the positive and negative electrode active slurry on both sides of the solid electrolyte membrane greatly improves the uniformity of the components of the positive and negative electrode active material layers, and improves the combination degree of the electrode active material and the solid electrolyte;

(2) The positive and negative electrode active slurry is sprayed on both sides of the solid electrolyte membrane, and then rolled together with the positive and negative electrode current collectors to form a whole, so the solid electrolyte material always maintains integrity and alleviates the uneven structure of the solid electrolyte material problems affecting battery performance.

Description of drawings

Fig. 1 is the schematic diagram that utilizes coating method to prepare the solid-state electrolyte lithium-ion battery of integration without interface of the present invention;

Fig. 2 is a schematic diagram of preparing the integrated non-interface solid electrolyte lithium-ion battery of the present invention by spraying method.

Detailed ways

The present invention will be further described in detail below with reference to the embodiments of the accompanying drawings. It should be noted that the following embodiments are intended to facilitate the understanding of the present invention, but do not limit it in any way.

Example 1:

In this example, an integrated lithium-ion battery was prepared by a coating method. In the integrated non-interface solid electrolyte lithium-ion battery, the positive electrode current collector is aluminum foil, and the positive active material layer on the positive electrode current collector is composed of LiFePO ₄ , Super P, and a binder; the negative electrode current collector is copper foil, and the positive electrode active material layer on the negative electrode current collector is copper foil. The negative electrode active material layer is composed of graphite, Super P, and a binder; the solid electrolyte material and the binder material are polyarylethersulfone lithium salts containing fluorine-containing sulfonimide groups in the side chain, and its structural formula is as follows:

The preparation method of the integrated non-interface solid electrolyte lithium-ion battery is shown in Figure 1, including the following

step:

(1) Preparation of binder solution

Dissolve the polyarylethersulfone lithium salt whose side chain is a fluorine-containing sulfonimide group in N-methylpyrrolidone at a concentration of 5wt% at 50°C, and stir thoroughly for 12 hours to prepare a fluorine-containing sulfonimide-based The binder solution of the base polymer lithium salt.

(2) Making positive and negative pole pieces

Stir and blend 80 parts by weight of LiFePO ₄ , 10 parts by weight of Super P and 10 parts by weight of binder solution that have been ground in advance to prepare a positive electrode active slurry; then coat the slurry evenly on a 20 μm aluminum foil, and coat The thickness of the covered positive electrode sheet is controlled at 200 μm±10 μm; after rolling, the positive electrode sheet 1 with a thickness of about 100 μm is obtained.

The preparation method of the negative electrode sheet is similar to the preparation of the positive electrode sheet, that is, 80 parts by weight of pre-ground graphite, 10 parts by weight of Super P and 10 parts by weight of binder solution are stirred and blended to prepare a negative electrode active slurry; The slurry is evenly coated on a 10 μm copper foil, and the total thickness of the coated negative electrode sheet is controlled at 180 μm±10 μm; after rolling, a negative electrode sheet 2 with a thickness of about 90 μm is obtained.

(3) Preparation of electrolyte membrane

Dissolve polyaryl ether sulfone lithium salt whose side chain is a fluorine-containing sulfonimide group in N-methylpyrrolidone at a concentration of 25 wt%, and stir thoroughly for 24 hours to obtain an electrolyte solution; the electrolyte solution is cast Coated on the active layer of the positive and negative electrode sheets; the total thickness of the electrode sheet is controlled within the range of 50-300 μm; the electrode sheet coated with the electrolyte is heated and dried for 72 hours in a vacuum environment to obtain the electrolyte membrane 3 . Among them, the thickness of the electrolyte membrane is optimal at 150 μm.

(4) The electrolyte membranes 3 of the dried positive and negative pole pieces are stacked facing each other, and the stack is pressed into a flat battery core with a thickness of less than 500 μm by hot rolling; finally, through slicing, winding, welding An integrated interfaceless lithium-ion battery is obtained through the processes of tab, packaging, electrification, and exhaust.

Example 2:

In this example, the preparation method of the integrated non-interface solid-state electrolyte lithium-ion battery is basically the same as in Example 1, except that the solid-state electrolyte material and the binder are both poly(5-sulfonyl chloride-3-oxa) Perfluorosulfonamide polymer lithium salt, wherein the thickness of the solid electrolyte membrane is still about 150 μm.

Example 3:

In this example, the preparation method of the integrated non-interface solid electrolyte lithium-ion battery is basically similar to Example 2, except that the binder material is a heterogeneous material but poly(5-sulfonyl chloride-3-oxa ) a mixture of perfluorosulfonamide polymer lithium salt and polyvinylidene fluoride (PVDF) in a mass ratio of 1:1.

The preparation method of the integrated non-interface solid electrolyte lithium-ion battery is shown in Figure 1, comprising the following steps:

(1) Preparation of binder solution

Poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide polymer lithium salt is mixed with polyvinylidene fluoride (PVDF) at a mass ratio of 1:1; the mixture is dissolved in N- In methylpyrrolidone, after fully stirring for 12 hours, a binder solution based on fluorine-containing sulfonimide-based polymer was prepared.

(2) Making positive and negative pole pieces

Stir and blend 80 parts by weight of LiFePO ₄ , 10 parts by weight of Super P and 10 parts by weight of binder solution that have been ground in advance to prepare a positive electrode active slurry; then coat the slurry evenly on a 20 μm aluminum foil. The thickness of the covered positive electrode sheet is controlled at 200 μm±10 μm; after rolling, the positive electrode sheet 1 with a thickness of about 100 μm is obtained.

The preparation method of the negative electrode sheet is similar to the preparation of the positive electrode sheet, that is, 80 parts by weight of pre-ground graphite, 10 parts by weight of Super P and 10 parts by weight of binder solution are stirred and blended to prepare a negative electrode active slurry; The slurry is evenly coated on a 10 μm copper foil, and the total thickness of the coated negative electrode sheet is controlled at 180 μm±10 μm; after rolling, a negative electrode sheet 2 with a thickness of about 90 μm is obtained.

(3) Preparation of electrolyte membrane

Dissolve poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide polymer lithium salt in N-methylpyrrolidone at a concentration of 25 wt%, and stir thoroughly for 24 hours to obtain an electrolyte solution; Coated on the active layer of the positive and negative electrode sheets; the total thickness of the electrode sheet was controlled within the range of 50-300 μm; the electrode sheet coated with the electrolyte was heated and dried for 72 hours in a vacuum environment to obtain the electrolyte membrane 3 . Among them, the thickness of the electrolyte membrane is optimal at 150 μm;

(4) The electrolyte membranes 3 of the dried positive and negative pole pieces are stacked facing each other, and the stack is pressed into a flat battery core with a thickness of less than 500 μm by hot rolling; finally, through slicing, winding, welding An integrated interfaceless lithium-ion battery is obtained through the processes of tab, packaging, electrification, and exhaust.

Example 4:

In this example, an integrated solid-state electrolyte lithium-ion battery without an interface is prepared by a spray coating method. Among them, the positive current collector is aluminum foil, and the positive active material layer on the positive current collector is composed of LiFePO ₄ , Super P, and a binder; the negative current collector is copper foil, and the negative active material layer on the negative current collector is made of graphite, SuperP , and the composition of the binder; the solid electrolyte material and the binder material are both poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide lithium salt.

The method of the integrated non-interface solid-state electrolyte lithium-ion battery is shown in Figure 2, comprising the following steps:

(1) Preparation of electrolyte membrane

Dissolve poly(5-sulfonyl chloride-3-oxa)perfluorosulfonamide lithium salt in N-methylpyrrolidone at a concentration of 25wt%, and stir thoroughly for 24 hours to obtain an electrolyte viscous solution; the electrolyte membrane is prepared by casting membrane method 4. The thickness of the film is about 50-200μm;

(2) Preparation of binder solution

Poly(5-sulfonyl chloride-3-oxa)perfluorosulfonamide lithium salt was dissolved in N-methylpyrrolidone at a concentration of 5wt%, and after stirring for 12 hours, a fluorine-containing sulfonimide-based polymer was prepared. binder solution;

(3) Preparation of positive and negative active slurry

Stirring and blending 80 parts by weight of LiFePO ₄ , 10 parts by weight of Super P and 10 parts by weight of binder solution to prepare positive electrode active slurry 5; the preparation method of negative electrode sheet and the preparation of positive electrode sheet Similar, be about to pre-ground 80 parts by weight of graphite, 10 parts by weight of Super P and 10 parts by weight of binder solution stirring and blending to prepare negative electrode active slurry 6;

(4) Active slurry spraying

The positive and negative electrode active slurry 5 and 6 are sprayed on both sides of the electrolyte membrane 4 respectively to form a three-layer sandwich film structure; the electrolyte membrane coating coated with the positive electrode active slurry corresponds to the positive electrode current collector 7-aluminum foil, and the negative electrode is coated with The electrolyte membrane coating of the active slurry corresponds to the negative current collector 8-copper foil, and is molded together with the electrolyte membrane on a roller press; finally, it is obtained by slicing, winding, welding tabs, packaging, electrochemistry, and exhaust. All-in-one interfaceless Li-ion battery.

Example 5:

In this example, the preparation method of the integrated non-interface solid electrolyte lithium-ion battery is basically similar to Example 4, except that the binder material is a heterogeneous material but poly(5-sulfonyl chloride-3-oxa ) a mixture of perfluorosulfonamide polymer lithium salt and polyvinylidene fluoride (PVDF) in a mass ratio of 1:1.

The method of the integrated non-interface solid-state electrolyte lithium-ion battery is shown in Figure 2, comprising the following steps:

(1) Preparation of electrolyte membrane

Dissolve poly(5-sulfonyl chloride-3-oxa)perfluorosulfonamide lithium salt in N-methylpyrrolidone at a concentration of 25wt%, and stir thoroughly for 24 hours to obtain an electrolyte viscous solution; the electrolyte is obtained by casting a film method The film 4 has a film thickness of about 50-200 μm.

(2) Prepare binder solution:

Mix poly(5-sulfonyl chloride-3-oxa)perfluorosulfonamide lithium salt with polyvinylidene fluoride (PVDF) at a mass ratio of 1:1; the mixture is dissolved in N-methylpyrrolidone at a concentration of 5wt%, After fully stirring for 12 hours, a binder solution based on a fluorine-containing sulfonimide-based polymer is prepared;

(3) Preparation of positive and negative active slurry

Stir and blend 80 parts by weight of LiFePO ₄ , 10 parts by weight of Super P and 10 parts by weight of binder solution that have been ground in advance to prepare positive active slurry 5; the preparation method of negative electrode sheet and the preparation of positive electrode sheet Similar, the graphite that is about to grind in advance 80 parts by weight, the Super P of 10 parts by weight and the binder solution of 10 parts by weight are stirred and blended and prepared into negative electrode active slurry 6;

(4) Active slurry spraying:

Spray the positive and negative electrode active slurry on both sides of the electrolyte membrane respectively to form a three-layer sandwich film structure; the electrolyte membrane coating coated with the positive electrode active slurry corresponds to the positive electrode current collector 7-aluminum foil, and the layer coated with the negative electrode active slurry The electrolyte membrane coating corresponds to the negative current collector 8-copper foil, and the electrolyte membrane is molded together on a roller press; finally, an integrated interface-free Lithium Ion Battery.

Embodiment 6:

In this example, the preparation method of the integrated non-interface solid electrolyte lithium-ion battery is basically similar to Example 4, the difference is that the solid electrolyte material and the binder material are both side chains containing fluorine-containing sulfonimide groups Group of polyether ether ketone resin material.

The method of the integrated non-interface solid-state electrolyte lithium-ion battery is shown in Figure 2, comprising the following steps:

(1) Preparation of electrolyte membrane

Dissolve polyetheretherketone resin whose side chain is a fluorine-containing sulfonimide group in N-methylpyrrolidone at a concentration of 30 wt%, and stir thoroughly for 24 hours to obtain an electrolyte viscous solution; the electrolyte membrane is prepared by casting membrane method 4. The thickness of the film is about 50-200μm;

(2) Preparation of binder solution

Mix the polyether ether ketone resin whose side chain is a fluorine-containing sulfonimide group with polyvinylidene fluoride (PVDF) at a mass ratio of 1:1; the mixture is dissolved in N-methyl In base pyrrolidone, after fully stirring for 12 hours, a binder solution based on a fluorine-containing sulfonimide-based polymer was prepared;

(3) Preparation of positive and negative active slurry

Pre-ground 80 parts by weight of LiFePO ₄ , 10 parts by weight of Super P and 10 parts by weight of binder solution are stirred and blended to prepare positive active slurry 5; the preparation method of negative electrode sheet is similar to that of positive electrode sheet , the graphite that is about to grind in advance 80 parts by weight, the Super P of 10 parts by weight and the binder solution of 10 parts by weight are stirred and blended and prepared into negative electrode active slurry 6;

(4) Active slurry spraying

The positive and negative active material slurries are sprayed on both sides of the electrolyte membrane respectively to form a three-layer sandwich film structure; the electrolyte membrane coating coated with the positive active material corresponds to the positive current collector 7-aluminum foil, and the electrolyte coated with the negative active material The film coating corresponds to the negative electrode current collector 8-copper foil, and is molded together with the electrolyte film on a roller press; finally, an integrated interfaceless lithium battery is obtained through slicing, winding, welding tabs, packaging, electrochemistry, and exhaust. ion battery.

Embodiment 7:

In this example, the preparation method of the integrated non-interface solid electrolyte lithium-ion battery is basically similar to Example 4, the difference is that the solid electrolyte membrane solid electrolyte material is poly(5-sulfonyl chloride-3-oxa) perfluoro A mixture of sulfonamide lithium salt surface-modified graphene composite material and poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide lithium salt blended at 5:95, the binder material is poly(5- A mixture of sulfonyl chloride-3-oxa)perfluorosulfonamide lithium salt and polyvinylidene fluoride (PVDF) at a mass ratio of 1:1.

The method of the integrated non-interface solid-state electrolyte lithium-ion battery is shown in Figure 2, comprising the following steps:

(1) Preparation of electrolyte membrane

The poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide lithium salt surface modified graphene composite material and poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide lithium salt were combined at 5:95 mixed, and dissolved in N-methylpyrrolidone at a concentration of 25wt% of the total mass fraction of solid mixed substances, and fully stirred for 24 hours to obtain an electrolyte viscous solution; the electrolyte membrane 4 was prepared by casting a membrane method, and the thickness of the membrane was about 50- 200μm;

(2) Preparation of binder solution

Mix poly(5-sulfonyl chloride-3-oxa)perfluorosulfonamide lithium salt with polyvinylidene fluoride (PVDF) at a mass ratio of 1:1; In base pyrrolidone, after fully stirring for 12 hours, a binder solution based on a fluorine-containing sulfonimide-based polymer was prepared;

(3) Preparation of positive and negative active slurry

Stir and blend 80 parts by weight of LiFePO ₄ , 10 parts by weight of Super P and 10 parts by weight of binder solution that have been ground in advance to prepare positive active slurry 5; the preparation method of negative electrode sheet and the preparation of positive electrode sheet Similar, 80 parts by weight of pre-ground poly(5-sulfonyl chloride-3-oxa) perfluorosulfonamide lithium salt surface modified graphene, 10 parts by weight of Super P and 10 parts by weight of binder solution Stirring and blending to prepare negative electrode active slurry 6;

(4) Active slurry spraying

Spray the positive and negative electrode active slurry on both sides of the electrolyte membrane respectively to form a three-layer sandwich film structure; the electrolyte membrane coating coated with the positive electrode active slurry corresponds to the positive electrode current collector 7-aluminum foil, and the electrolyte coated with the negative electrode active material The film coating corresponds to the negative electrode current collector 8-copper foil and the electrolyte film are molded together on a roller press; finally, an integrated interfaceless lithium ion is obtained through slicing, winding, welding tabs, packaging, electrochemistry, and exhaust. Battery.

Claims (8)

1. the preparation method of the integrated solid electrolyte lithium ion battery without interface, the solid electrolyte lithium ion battery packet Include plus plate current-collecting body, anode active material layer, negative current collector, anode active material layer, solid electrolyte membrane；The anode Active material layer includes positive electrode active materials, conductive agent and binder；The anode active material layer includes negative electrode active material Material, conductive agent and binder；It is characterized in that：The binder polymerize with solid electrolyte comprising fluorine-containing sulfimide of the same race Object component；

The fluorine-containing sulfonimide polymer is that the straight chain polymer of fluorine-containing sulfimide base or fluorine-containing sulfimide base gather Close the composite material of object surface-modified inorganic nano particle；

The preparation method includes the following steps：

(1) positive electrode active materials, conductive agent, binder and the first solvent are uniformly mixed, positive-active slurry is made；It will bear Pole active material, conductive agent, binder and the second solvent are uniformly mixed, and negative electrode active slurry is made；

(2) positive-active slurry is coated on plus plate current-collecting body surface, prepares anode pole piece；Negative electrode active slurry is coated on negative Pole collection liquid surface, prepares cathode pole piece；

(3) solid electrolyte material is dissolved in third solvent, electrolyte solution is made；

(4) electrolyte solution is respectively coated in anode pole piece surface and cathode pole piece surface, drying removes shape after third solvent At dielectric film, anode pole piece is superimposed with cathode pole piece, keeps the two sides of coated electrolyte film opposite, then hot-rolling pressure, it will be electric Pole layer and dielectric film consolidation.

2. the preparation method of solid electrolyte lithium ion battery of the integration without interface as described in claim 1, it is characterized in that： The fluorine-containing sulfonimide polymer is poly- (the chloro- 3- oxa-s of 5- sulphonyl) perfluor sulfonyl amine lithium salts, and fluorine-containing sulfimide base is poly- One or both of polymer modified graphene.

3. the preparation method of solid electrolyte lithium ion battery of the integration without interface as described in claim 1, it is characterized in that： The positive electrode active materials include the mixing material of one or more of cobalt acid lithium, LiMn2O4, nickel ion doped.

4. the preparation method of solid electrolyte lithium ion battery of the integration without interface as described in claim 1, it is characterized in that： The negative electrode active material includes that graphite, graphene, carbon nanotube, lithium-containing transition metal nitride, silica, silicon substrate are compound The mixing material of one or more of material, sulfur-bearing inorganic compound.

5. the preparation method of solid electrolyte lithium ion battery of the integration without interface as described in claim 1, it is characterized in that： The conductive agent includes the mixing material of one or more of acetylene black, Super P, carbon black.

6. the preparation method of solid electrolyte lithium ion battery of the integration without interface as described in claim 1, it is characterized in that： First solvent include one kind in water, methanol, ethyl alcohol, normal propyl alcohol, isopropanol, n-butanol, N-Methyl pyrrolidone or Two or more mixtures；

Second solvent includes one in water, methanol, ethyl alcohol, normal propyl alcohol, isopropanol, n-butanol, N-Methyl pyrrolidone Kind material or two or more mixtures；

The third solvent includes ethylene carbonate (EC), propene carbonate (CP), dimethyl carbonate (DMC), methyl ethyl carbonate Ester (EMC), diethyl carbonate (DEC), Y- fourths propyl ester (GBL), methyl formate (MF), methyl acetate (MVA), tetrahydrochysene bark and mutter (THF), a kind of solvent in l, 2- dimethoxy-ethane (DME) or two or more mixtures.

7. the preparation method of the integrated solid electrolyte lithium ion battery without interface, it is characterized in that：The solid electrolyte lithium Ion battery includes plus plate current-collecting body, anode active material layer, negative current collector, anode active material layer, solid electrolyte membrane； The anode active material layer includes positive electrode active materials, conductive agent and binder；The anode active material layer includes Negative electrode active material, conductive agent and binder；It is characterized in that：Include fluorine-containing sulphur of the same race in the binder and solid electrolyte Imide polymer component；

The fluorine-containing sulfonimide polymer is that the straight chain polymer of fluorine-containing sulfimide base or fluorine-containing sulfimide base gather Close the composite material of object surface-modified inorganic nano particle；

The preparation method includes the following steps：

(1) positive electrode active materials, conductive agent, binder and the first solvent are uniformly mixed, positive-active slurry is made；It will bear Pole active material, conductive agent, binder and the second solvent are uniformly mixed, and negative electrode active slurry is made；

(2) positive-active slurry and negative electrode active slurry are sprayed on to the two sides of solid electrolyte membrane respectively；

(3) plus plate current-collecting body is arranged to the side for being coated with positive-active slurry in dielectric film, negative current collector 8 is arranged in electricity Solution plasma membrane is coated with the side of negative electrode active slurry, then hot-rolling pressure, and electrode layer and dielectric film compacting are integrated.

8. the preparation method of solid electrolyte lithium ion battery of the integration without interface as claimed in claim 7, it is characterized in that： First solvent include one kind in water, methanol, ethyl alcohol, normal propyl alcohol, isopropanol, n-butanol, N-Methyl pyrrolidone or Two or more arbitrary proportion mixtures；

Second solvent includes one in water, methanol, ethyl alcohol, normal propyl alcohol, isopropanol, n-butanol, N-Methyl pyrrolidone Kind or two or more arbitrary proportion mixtures.