CN205488409U - Short circuit testing arrangement in battery - Google Patents

Abstract

The utility model relates to a short circuit testing arrangement in battery, include the battery and set up in the inside interior short circuit triggering element of this battery that this battery is including separating the diaphragm anodal and negative pole, short circuit triggering element be the sheet structure in being somebody's turn to do supporting part and a plurality of deformation portion, these a plurality of deformation portions and this supporting part structure as an organic whole, these a plurality of deformation portions symmetry mutual for this supporting part sets up, and this deformation portion has the pointed end, should have the temperature of triggering by interior short circuit triggering element, and short circuit triggering element's temperature equals or is higher than in the time of should triggering the temperature in this, and deformation takes place and makes this pointed end impale this diaphragm to this unfamiliar direction for this deformation portion to cause the interior short circuit of this battery.

Description

Battery internal short circuit test device

technical field

The utility model belongs to the technical field of batteries, in particular to a battery internal short-circuit testing device.

Background technique

Most safety issues of lithium-ion power batteries can be controlled or mitigated through external measures such as electrical management or temperature management. Most electric vehicle manufacturers today have applied such measures in their power battery modules to improve safety. However, thermal runaway caused by internal short circuit is the most difficult and difficult issue among all safety issues. There are many causes of internal short circuit, and various situations or reasons may lead to different degrees of internal short circuit and danger. Some external measures such as electrical management or temperature management can be effectively controlled and mitigated. Most of the safety problems in the normal use of batteries are related to internal short circuits, not only in the field of electric vehicles, but also in other fields that use lithium-ion batteries, such as digital products and aircraft.

At present, the discovery and prediction of internal short circuit is still a difficult point in battery safety. The internal short circuit test methods in many standards, such as extrusion, acupuncture, external short circuit, etc., will destroy the integrity of the battery during the test and cause serious damage to the battery, which is fundamentally different from the internal short circuit that occurs during actual use. The difference can not truly simulate the internal short circuit state of the battery. Therefore, the main difficulty in today's internal short circuit testing and research is to find a suitable method to trigger the internal short circuit.

Utility model content

In view of this, it is indeed necessary to provide a battery internal short-circuit test device that can truly simulate the internal short-circuit state of the battery.

A battery internal short-circuit test device, including a battery and an internal short-circuit trigger element arranged inside the battery, the battery includes a separator separating the positive electrode and the negative electrode, the internal short-circuit trigger element is a sheet structure, including a support part and a plurality of deformation parts , the plurality of deformation parts and the support part are integrally structured, the plurality of deformation parts are arranged symmetrically with respect to the support part, the deformation part has a sharp point, and the internal short-circuit trigger element has a trigger temperature. When the internal short-circuit trigger element When the temperature is equal to or higher than the triggering temperature, the deformation part deforms toward the diaphragm and the tip pierces the diaphragm, thereby causing a short circuit in the battery.

The battery internal short circuit test device and trigger method provided by the utility model trigger the deformation of the internal short circuit trigger element through temperature changes to pierce the battery diaphragm to cause the battery internal short circuit. The method is simple, convenient and easy to operate. The internal short circuit trigger element does not It will damage the integrity of the battery, and can more realistically simulate the internal short circuit state of the battery during actual use, which provides a reliable and efficient internal short circuit for battery safety research and safety performance evaluation and comparison during battery design The triggering method plays a key role in the research in the field of battery internal short circuit, as well as the safety performance evaluation in battery design, development and performance comparison.

Description of drawings

FIG. 1 is a schematic structural diagram of a battery internal short-circuit test device according to a first embodiment of the present invention.

Fig. 2 is a top view of an internal short circuit trigger element according to an embodiment of the present invention.

Fig. 3 is a top view of an internal short-circuit trigger element according to another embodiment of the present invention.

Fig. 4 is a top view of an internal short-circuit trigger element according to another embodiment of the present invention.

Fig. 5a is a side view of the internal short-circuit trigger element before deformation according to an embodiment of the present invention.

Fig. 5b is a side view of an internal short-circuit trigger element deformed according to an embodiment of the present invention.

6 is a schematic diagram of the internal short circuit triggering element triggering the positive electrode material-negative electrode material type internal short circuit according to the first embodiment of the present invention.

7 is a schematic diagram of the internal short circuit triggering element triggering the negative electrode material-positive electrode current collector type internal short circuit according to the first embodiment of the present invention.

FIG. 8 is a schematic structural diagram of a battery internal short-circuit test device according to a second embodiment of the present invention.

9 is a schematic diagram of the internal short circuit triggering element triggering the positive electrode material-negative electrode current collector type internal short circuit according to the second embodiment of the present invention.

10 is a schematic diagram of the internal short circuit triggering element triggering the positive electrode current collector-negative electrode current collector type internal short circuit according to the second embodiment of the present invention.

Description of main component symbols

Test device 10

battery 100

Positive current collector 110

Cathode material layer 120

Diaphragm 130

Negative electrode material layer 140

Negative electrode collector 150

Internal short-circuit trigger element 200

Deformation Department 210

Tip 212

Support 220

The following specific embodiments will further illustrate the utility model in conjunction with the above-mentioned accompanying drawings.

detailed description

A battery internal short-circuit testing device of the present invention will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 1 , the first embodiment of the present invention provides a battery internal short circuit testing device 10 , which includes a battery 100 and at least one internal short circuit triggering element 200 disposed inside the battery 100 . The battery 100 includes a diaphragm 130 , and the internal short-circuit triggering element 200 is a sheet-like structure, including a support portion 220 and a plurality of deformation portions 210 , and the plurality of deformation portions 210 are integrated with the support portion. The plurality of deforming parts 210 are arranged symmetrically with respect to the supporting part 220 . Each deformation portion 210 has at least one tip 212 . The internal short-circuit triggering element 200 has a triggering temperature. When the temperature of the internal short-circuit triggering element 200 is equal to or higher than the triggering temperature, the deformation part 210 deforms toward the diaphragm 130 and makes the tip 212 deform the diaphragm 130 piercing, thereby causing a short circuit in the battery 100 , and the support portion 220 does not deform. The plurality of deformable parts 210 are disposed around the supporting part 220 and arranged symmetrically, preferably with the same shape, so that the supporting part 220 is evenly stressed and kept in a fixed position in the battery 100, so that the deformable parts 210 are deformed. Provide support when piercing the septum 130 during the procedure.

The internal short-circuit triggering element 200 is an integrally formed polygonal sheet structure, which can be arranged parallel to the diaphragm 130 . In this embodiment, the diaphragm 130 is in direct contact with the diaphragm 130 and is stacked. The internal short-circuit trigger element 200 has a temperature memory effect, and can deform the deformation portion 210 at the trigger temperature. When the deformation part 210 is deformed, the side of the deformation part 210 with the tip 212 bends toward the diaphragm 130 , and the tip 212 pierces the diaphragm, thereby causing an internal short circuit of the battery 100 . The internal short trigger element 200 has the strength to pierce the separator 130 or other internal components of the battery 100 . The length of the deformation portion 210 is greater than the thickness of the diaphragm 130 . It can be understood that, since the thickness of the diaphragm 130 is relatively thin, the length of the deformation portion 210 may be relatively small, such as 0.5 mm˜1 mm.

Please refer to FIG. 2 , in one embodiment, the supporting portion 220 of the internal short-circuit triggering element 200 is rectangular. The deforming part 210 is triangular in shape, and there are four in number, which are respectively arranged on the four sides of the rectangle of the support part 220 , and the side connected to the support part 220 is equal to the length of the side of the rectangle. The outward corner of the deformation part 210 has the tip 212 . Preferably, the supporting part 220 is a square, and the deforming part 210 is an isosceles triangle or an equilateral triangle.

Please refer to FIG. 3 , in another embodiment, the supporting portion 220 of the internal short-circuit triggering element 200 is a centrally symmetrical 12-sided shape. The deforming part 210 is triangular in shape, and there are four in number, which are respectively arranged on four sides symmetrical to the center of the 12-sided shape of the supporting part 220 . The outward corner of the deformation part 210 has the tip 212 . Preferably, the deformation portion 210 is an isosceles triangle or an equilateral triangle. The outward angle of the deformation portion 210 is preferably an acute angle, such as 30°.

Please refer to FIG. 4 , in yet another embodiment, the support portion 220 of the internal short-circuit trigger element 200 is rectangular, the deformation portion 210 is a right triangle, and the number is four, which are respectively arranged on the four corners of the support portion 220 . A right angle of the deformation part 210 is disposed on a corner of the support part 220 , and a right angle side of the deformation part 210 is aligned with a side of the support part 220 .

In one embodiment, the internal short circuit triggering element 200 is a memory alloy, such as Nitinol, which has a transition temperature, ie, the triggering temperature. Please refer to FIG. 5 , before being assembled into the battery 100, the internal short-circuit trigger element 200 is processed above the transformation temperature to make the battery 100 undergo an internal short circuit, that is, the deformed shape of the internal short-circuit trigger element 200, and then Below the transformation temperature, the internal short-circuit triggering element 200 is processed into a shape when it is not triggered inside the battery 100 , as shown in FIG. 5 a . When the temperature of the battery 100 reaches the above transition temperature, the internal short circuit trigger element 200 is deformed and the diaphragm 130 is pierced to cause an internal short circuit of the battery 100, as shown in FIG. 5b, the transition temperature is the internal short circuit trigger element 200 trigger temperature. Since there are multiple deformation parts 210 , when deformation occurs, multiple sharp ends 212 deform simultaneously, piercing the septum 130 at multiple positions.

The trigger temperature can be higher than the normal use temperature of the battery 100 and lower than the melting point of the separator 130, so that the internal short circuit trigger element 200 will not affect the normal use of the battery 100 when it is not triggered, but when it is triggered, the The diaphragm 130 will not melt, and the internal short circuit of the battery 100 is controlled only by the deformation of the internal short circuit triggering element 200 . Preferably, the trigger temperature is from 55°C to 170°C. The normal use of the battery 100 refers to the daily use state in which the battery 100 is not intentionally heated in products such as electric vehicles and mobile phones.

The number of the internal short circuit triggering element 200 may be one, and the one internal short circuit triggering element 200 may be arranged at different positions in the battery 100 to realize internal short circuits at different positions. The number of the internal short circuit triggering elements 200 can also be multiple, and the multiple internal short circuit triggering elements 200 can be arranged at different positions in the battery 100, so that the battery 100 triggers internal short circuits at multiple positions at the same time.

The battery 100 includes a positive electrode current collector 110 , a positive electrode material layer 120 , a separator 130 , a negative electrode material layer 140 and a negative electrode current collector 150 . The positive electrode material layer 120 is disposed on the surface of the positive electrode current collector 110 . The negative electrode material layer 140 is disposed on the surface of the negative electrode current collector 150 . The positive electrode material layer 120 is spaced apart from the negative electrode material layer 140 through the separator 130 . The positive electrode collector 110 , the positive electrode material layer 120 , the separator 130 , the negative electrode material layer 140 and the negative electrode current collector 150 are sequentially stacked. The battery 100 may further include an electrolyte or electrolyte solution (not shown in the figure), disposed between the positive electrode material layer 120 and the negative electrode material layer 140 . The battery 100 may further include an encapsulation structure (not shown in the figure), the encapsulation structure accommodates the anode current collector 110 , the anode material layer 120 , the separator 130 , the anode material layer 140 and the anode current collector 150 . The battery 100 can be a stacked battery or a wound battery.

The internal short-circuit trigger element 200 can be disposed in the positive electrode material layer 120, in the negative electrode material layer 140, between the positive electrode material layer 120 and the positive electrode current collector 110, between the positive electrode material layer 120 and the separator 130, the Between the negative electrode material layer 140 and the negative electrode current collector 150 or between the negative electrode material layer 140 and the separator 130 .

Please refer to FIG. 6 , when the internal short-circuit triggering element 200 is in use, when the temperature of the internal short-circuit triggering element 200 is deformed due to the overcharging of the battery 100 or the overheating of the ambient temperature, the deformation part 210 has a tip 212 The side is bent in the direction of the diaphragm 130, thereby directly piercing the diaphragm 130 to cause an internal short circuit. In this embodiment, when the internal short circuit triggering element 200 is deformed, only the separator 130 is pierced, thereby initiating a positive electrode material-negative electrode material type internal short circuit. When it is only necessary to initiate an internal short circuit of the positive electrode material-negative electrode material type, the deformation part 210 of the internal short circuit trigger element 200 can be insulating or conductive, such as a memory alloy metal sheet wrapped by an insulating material, as long as It is sufficient that the positive and negative electrode materials can be brought into contact when the separator 130 is pierced.

Please refer to FIG. 7 , in another embodiment, the deformation part 210 has a larger size, and can contact the opposite current collector after triggering the deformation. When the deformation part 210 is deformed, the separator 130 and the positive electrode material layer 120 are simultaneously pierced and contacted with the positive electrode current collector 110, causing an internal short circuit of the negative electrode material-positive electrode current collector type; when the internal short circuit triggers the element When 200 is placed between the positive electrode material layer 120 and the separator, when the deformation part 210 is deformed, the separator 130 and the negative electrode material layer 140 are simultaneously pierced, and come into contact with the negative electrode current collector 150, resulting in positive electrode material-negative electrode collector Fluid type internal short circuit. In this embodiment, the internal short-circuit triggering element 200 is electrically conductive as a whole.

Please refer to FIG. 8 , the second embodiment of the utility model provides a battery internal short circuit test device 10, the structure is basically the same as that of the first embodiment, the only difference is that the internal short circuit trigger element 200 is arranged between the negative electrode current collector 150 and the negative electrode between the material layers 140 , or between the positive electrode current collector 110 and the positive electrode material layer 120 .

Please refer to FIG. 9, for example, when the internal short circuit trigger element 200 is disposed between the negative electrode current collector 150 and the negative electrode material layer 140, when the internal short circuit trigger element 200 is deformed, the plurality of deformed parts 210 have One side of the tip 212 bends toward the separator 130 , and simultaneously pierces the negative electrode material layer 140 and the separator 130 to cause an internal short circuit. The length of the deformation portion 210 is greater than the sum of the thicknesses of the separator 130 and the negative electrode material layer 140 , and smaller than the sum of the thicknesses of the separator 130 , the positive electrode material layer 120 and the negative electrode material layer 140 . The entire internal short-circuit triggering element 200 may be conductive. When the internal short circuit triggering element 200 is deformed, only the negative electrode material layer 140 and the separator 130 are pierced simultaneously, thereby triggering a positive electrode material-negative electrode current collector type internal short circuit.

Please refer to FIG. 10 , in another embodiment, the internal short-circuit triggering element 200 may be conductive as a whole. The length of the deformation portion 210 is equal to or greater than the sum of the thicknesses of the separator 130 , the positive electrode material layer 120 and the negative electrode material layer 140 . When the internal short-circuit trigger element 200 is deformed, the negative electrode material layer 140, the separator 130, and the positive electrode material layer 120 are pierced simultaneously, and are in contact with the positive electrode current collector 110, thereby triggering a positive electrode current collector-negative electrode current collector type internal short circuit.

Similar to the above, the internal short circuit triggering element 200 can be disposed between the positive electrode current collector 110 and the positive electrode material layer 120 to trigger an internal short circuit of positive electrode current collector-negative electrode material type or positive electrode current collector-negative electrode current collector type.

When using the test device 100 to perform a battery internal short circuit test, a heating device (not shown) can be used to heat the battery 100 as a whole and heat up the battery 100 as a whole, thereby heating up the internal short circuit trigger element 200 and causing the battery 100 to heat up. When the internal short circuit triggering element 200 reaches its trigger temperature, it is deformed to cause the internal short circuit of the battery 100 .

The internal short-circuit trigger element only needs to make the tip pierce the diaphragm, so the area of the internal short-circuit trigger element required is very small, far less than the total area of the battery diaphragm, so that when the internal short-circuit trigger element is not triggered The original performance of the battery will not be affected. In one embodiment, the area of the internal short trigger element is less than 1% of the total area of the diaphragm.

Different locations, different initial sizes and different types of batteries have different extension speeds and severity of short circuits. The material, shape, size parameters, deformation and conductivity of the internal short-circuit trigger element can be designed, as well as the setting position of the internal short-circuit trigger element in the battery can be designed, so as to realize different positions, different initial scales and different types The internal short circuit of the battery provides a reliable and efficient internal short circuit trigger method for battery safety research and battery design safety performance evaluation and comparison. The test device and the triggering method play a key role in the research of the battery internal short circuit field, as well as the safety performance evaluation in battery design, development and performance comparison.

In addition, those skilled in the art can also make other changes within the spirit of the utility model. Of course, these changes made according to the spirit of the utility model should be included in the scope of protection claimed by the utility model.

Claims (10)

1. a battery internal short-circuit test device, including battery, this battery includes separating positive pole and the barrier film of negative pole, it is characterized in that, farther include to be arranged at the internal short-circuit trigger element of this inside battery, this internal short-circuit trigger element is laminated structure, including supporting part and multiple deformations, the plurality of deformations is structure as a whole with this supporting part, the plurality of deformations is symmetrically set relative to this supporting part, this deformations has tip, this internal short-circuit trigger element has a triggering temperature, when the temperature of this internal short-circuit trigger element is equal to or higher than this triggering temperature, this deformations deforms upon and makes this tip to be pierced through by this barrier film to the direction of this barrier film, thus cause this battery internal short-circuit.

2. battery internal short-circuit test device as claimed in claim 1, it is characterised in that the plurality of deformations is arranged on around this supporting part, and the plurality of deformations is of similar shape.

3. battery internal short-circuit test device as claimed in claim 2, it is characterized in that, it is characterized in that, the supporting part of this internal short-circuit trigger element is rectangle, this deformations is triangle, quantity is 4, is separately positioned on the four edges of this supporting part rectangle, and equal with the length of side of this rectangle with the limit that this supporting part connects.

4. battery internal short-circuit test device as claimed in claim 2, it is characterised in that it is characterized in that, 12 limit shapes symmetrical centered by the supporting part of this internal short-circuit trigger element, this deformations is triangle, and quantity is 4, is separately positioned in 12 limit shapes of this supporting part on the four edges being centrosymmetric.

5. battery internal short-circuit test device as claimed in claim 2, it is characterized in that, the supporting part of this internal short-circuit trigger element is rectangle, this deformations is right angled triangle, quantity is 4, the right angle of this deformations is arranged on the angle of this supporting part, and a right-angle side of this deformations aligns with a limit of this supporting part.

6. battery internal short-circuit test device as claimed in claim 1, it is characterised in that this internal short-circuit trigger element is arranged with this membrane contacts stacking, and the length of this deformations is more than the thickness of this barrier film.

7. battery internal short-circuit test device as claimed in claim 6, it is characterized in that, this battery farther includes positive electrode material layer and the negative electrode material layer separated by this barrier film, this internal short-circuit trigger element is arranged between this positive electrode material layer and this barrier film, and the length of this deformations is more than or equal to this barrier film and the thickness sum of this negative electrode material layer.

8. battery internal short-circuit test device as claimed in claim 6, it is characterized in that, this battery farther includes positive electrode material layer and the negative electrode material layer separated by this barrier film, this internal short-circuit trigger element is arranged between the negative electrode material layer of this battery and this barrier film, and the length of this deformations is more than or equal to this barrier film and the thickness sum of this positive electrode material layer.

9. battery internal short-circuit test device as claimed in claim 1, it is characterized in that, this battery farther includes plus plate current-collecting body, the positive electrode material layer being arranged on this plus plate current-collecting body, negative current collector and the negative electrode material layer being arranged on this negative current collector, this positive electrode material layer is separated by this barrier film with this negative electrode material layer, this internal short-circuit trigger element is arranged between this negative electrode material layer and this negative current collector, and the length of this deformations is more than this barrier film and the thickness sum of this negative electrode material layer.

10. battery internal short-circuit test device as claimed in claim 1, it is characterized in that, this battery farther includes plus plate current-collecting body, the positive electrode material layer being arranged on this plus plate current-collecting body, negative current collector and the negative electrode material layer being arranged on this negative current collector, this positive electrode material layer is separated by this barrier film with this negative electrode material layer, this internal short-circuit trigger element is arranged between this positive electrode material layer and this plus plate current-collecting body, and the length of this deformations is more than this barrier film and the thickness sum of this positive electrode material layer.