Button cell

Abstract

The utility model provides a button battery which comprises a shell, a battery cell assembly is arranged in the shell, the battery cell assembly comprises a positive pole piece, a negative pole piece and an insulating diaphragm, and the insulating diaphragm is located between the positive pole piece and the negative pole piece; and the insulating spacing layer coats the end part of the positive pole piece and / or the end part of the negative pole piece so as to separate the end part of the positive pole piece from the end part of the negative pole piece. According to the application, the insulating spacing layer is arranged at the end part of the positive pole piece and / or the negative pole piece, so that the end parts of the positive pole piece and the negative pole piece can be separated, and the insulating spacing layer can avoid direct contact between the positive pole piece and the negative pole piece when the battery is extruded, impacted by a heavy object, collided, needled, dropped and the like; therefore, the phenomena of short circuit and thermal runaway are avoided, and the safety problems of the button cell in the conditions of extrusion, heavy object impact, collision, needling, falling and the like are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a button battery. Background Art

[0002] The internal structure of button batteries with traditional structures can be easily damaged when they are squeezed, hit by heavy objects, collided, punctured, or dropped. The positive and negative electrodes inside the battery can easily come into contact, the positive electrode and the cover assembly can easily come into contact, and the negative electrode and the electrode can easily come into contact, which can easily lead to short circuits and thermal runaway, thus causing safety problems. Utility Model Content

[0003] The embodiment of the utility model provides a button battery, which can improve the thermal runaway problem that is prone to occur when the internal structure of the button battery is damaged.

[0004] The embodiment of the utility model provides a button battery, comprising:

[0005] A shell, wherein a battery cell assembly is disposed in the shell, wherein the battery cell assembly includes a positive electrode sheet, a negative electrode sheet and an insulating diaphragm, wherein the insulating diaphragm is located between the positive electrode sheet and the negative electrode sheet;

[0006] The insulating spacer layer is coated on the end of the positive electrode sheet and / or the end of the negative electrode sheet to separate the end of the positive electrode sheet from the end of the negative electrode sheet.

[0007] In an embodiment of the present application, an insulating spacer layer is coated on the end of the positive electrode sheet and / or the end of the negative electrode sheet, so that the positive electrode sheet can be separated from the end of the negative electrode sheet. When the battery is squeezed, impacted by heavy objects, collided, punctured, or dropped, the insulating spacer layer can avoid direct contact between the positive electrode sheet and the negative electrode sheet, thereby avoiding short circuit and thermal runaway, thereby improving the safety issues of button batteries in situations such as squeezing, impacted by heavy objects, collided, punctured, or dropped.

[0008] In one embodiment, the insulating spacer layer and the insulating membrane are integrally provided.

[0009] In one embodiment, the end of the insulating separator exceeds the end of the positive electrode sheet and the negative electrode sheet.

[0010] In an embodiment of the present application, setting the end of the insulating diaphragm to extend beyond the end of the positive electrode plate and the negative electrode plate can ensure that the positive electrode plate and the negative electrode plate do not come into direct contact when the battery is squeezed, impacted by heavy objects, collided, punctured, or dropped.

[0011] In one embodiment, the outer shell includes a shell cover and a shell body sealed with the shell cover, the pole is passed through the shell cover and is electrically insulated from the shell cover, and a first insulating layer is provided on a surface of the pole close to the battery cell assembly.

[0012] In one embodiment, a positive electrode tab is provided at one end of the positive electrode sheet close to the shell cover, the positive electrode tab is electrically connected to the pole, and a second insulating layer is provided on the surface of the positive electrode tab exposed inside the shell.

[0013] In the embodiment of the present application, by providing a first insulating layer on the surface of the pole, when the battery is squeezed, impacted by heavy objects, collided, punctured, and dropped, the pole can be separated from the negative pole piece, and the direct contact between the negative pole piece and the pole can be prevented, thereby avoiding short circuit and thermal runaway phenomena, and improving the safety of the battery. By providing a second insulating layer on the surface of the positive pole ear, when the battery is squeezed, impacted by heavy objects, collided, punctured, and dropped, the positive pole ear can be separated from the negative pole piece, and the direct contact between the negative pole piece and the positive pole ear can be prevented, thereby avoiding short circuit and thermal runaway phenomena, and improving the safety of the battery.

[0014] In one embodiment, a negative electrode tab is provided at one end of the negative electrode plate close to the shell cover, the negative electrode tab is electrically connected to the shell cover and the shell, and a third insulating layer is provided on the surface of the negative electrode tab exposed in the shell.

[0015] In an embodiment of the present application, by providing a third insulating layer on the surface of the negative electrode tab, the negative electrode tab can be separated from the positive electrode plate when the battery is squeezed, impacted by heavy objects, collided, punctured, or dropped, etc., and direct contact between the negative electrode tab and the positive electrode plate can be prevented, thereby avoiding short circuit and thermal runaway phenomena and improving the safety of the battery.

[0016] In one embodiment, a fourth insulating layer is provided on a surface of the shell cover exposed inside the housing.

[0017] In an embodiment of the present application, by providing a fourth insulating layer on the surface of the shell cover, the shell cover and the positive electrode plate can be separated when the battery is squeezed, impacted by heavy objects, collided, punctured, or dropped, etc., and direct contact between the shell cover and the positive electrode plate can be prevented, thereby avoiding short circuits and thermal runaway phenomena, thereby improving the safety of the battery.

[0018] In one embodiment, the pole is disposed through the middle of the shell cover, and the fourth insulating layer is in a circular ring shape.

[0019] In one embodiment, the battery cell assembly is wound, and a support rod is arranged at the center of the wound battery cell assembly, and the length of the support rod is smaller than the length of the battery cell assembly along the winding axis.

[0020] In the embodiments of the present application, by arranging a support rod in the center of the battery cell assembly, the battery can be prevented from deformation and damage when it is squeezed, impacted by heavy objects, collided, punctured, or dropped, thereby avoiding short circuit or thermal runaway and improving the safety of the battery. The support rod plays a supporting role in the process of button cell extrusion deformation, and can control the degree of deformation of the button cell and the internal winding core during the extrusion process, avoiding bending of the positive and negative pole pieces, thereby piercing the diaphragm and directly contacting, causing short circuit and thermal runaway. At the same time, the length of the support rod is less than the length of the battery cell assembly along the winding axis, which can avoid affecting the welding seal after liquid injection.

[0021] In one embodiment, the support rod is a cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 is a cross-sectional view of a button battery provided by one embodiment of the utility model;

[0024] Figure 2 is a cross-sectional view of a button battery provided by one embodiment of the utility model;

[0025] Figure 3 is a cross-sectional view of a button battery provided by one embodiment of the utility model;

[0026] Figure 4 It is a schematic structural diagram of a positive electrode tab and a positive electrode sheet provided in an embodiment of the utility model;

[0027] Figure 5 It is a top view of a battery cell assembly provided by an embodiment of the utility model (the positive electrode tab, the negative electrode tab, the second insulating layer, and the third insulating layer are not shown).

[0028] Among them, 10 is an outer shell, 101 is a shell, 102 is a shell cover, 20 is a battery cell assembly, 201 is a positive electrode plate, 202 is a negative electrode plate, 203 is an insulating diaphragm, 204 is a support rod, 205 is a positive electrode ear, 206 is a negative electrode ear, 207 is a second insulating layer, 208 is a third insulating layer, 30 is a pole, 40 is a first insulating layer, and 50 is a fourth insulating layer. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the utility model, and are not used to limit the utility model. In the utility model, unless otherwise stated, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0030] See also Figure 1 , 2 , 3 and Figure 5 , an embodiment of the present application provides a button battery, comprising:

[0031] The housing 10 has a battery cell assembly 20 disposed therein. The battery cell assembly 20 includes a positive electrode sheet 201, a negative electrode sheet 202, and an insulating diaphragm 203. The insulating diaphragm 203 is located between the positive electrode sheet 201 and the negative electrode sheet 202.

[0032] The insulating spacer layer is coated on the end of the positive electrode sheet 201 and / or the end of the negative electrode sheet 202 to separate the end of the positive electrode sheet 201 from the end of the negative electrode sheet 202 .

[0033] It is understood that the insulating spacer layer can be an insulating material such as an insulating film or insulating tape. The insulating spacer layer can only cover the end of the negative electrode plate 202 (such as Figure 1 As shown), it is also possible to only cover the end of the positive electrode sheet 201 (as shown Figure 2 As shown), the end of the positive electrode sheet 201 may be partially covered by the insulating spacer layer, and the end of the positive electrode sheet 201 may be partially covered by the insulating spacer layer (as shown). Figure 3 As shown), it can also cover both the end of the positive electrode sheet 201 and the end of the negative electrode sheet 202.

[0034] In one embodiment, the insulating spacer layer and the insulating membrane 203 are integrally formed.

[0035] It can be understood that the insulating spacer layer can be a part of the insulating diaphragm 203, and the length of the insulating diaphragm 203 can be set to exceed both ends of the positive electrode plate 201 and the negative electrode plate 202. The insulating spacer layer can also be an insulating material such as an insulating film or insulating tape arranged on the insulating diaphragm 203.

[0036] See also Figures 1 to 3 and Figure 4 In one embodiment, the outer shell 10 includes a shell cover 102 and a shell body 101 sealed and connected to the shell cover 102, a pole 30 is arranged on the shell cover 102, the pole 30 is passed through the shell cover 102 and is electrically insulated from the shell cover 102, a positive pole ear 205 is arranged at one end of the positive pole sheet 201 close to the shell cover 102, the positive pole ear 205 is electrically connected to the pole 30, and a first insulating layer 40 is arranged on the surface of the pole 30 close to the battery cell assembly 20.

[0037] It can be understood that the first insulating layer 40 is used to cover the surface of the pole 30 to prevent direct contact between the negative electrode plate 202 and the pole 30. The first insulating layer 40 can cover the entire surface or part of the surface of the pole 30 close to the battery cell assembly 20. The first insulating layer 40 can cover the positive electrode tab 205 and the surface of the pole 30 close to the battery cell assembly 20.

[0038] In one embodiment, a second insulating layer 207 is disposed on the surface of the positive electrode tab 205 exposed inside the housing 10 .

[0039] It can be understood that the second insulating layer 207 is used to cover the surface of the positive electrode tab 205 to prevent direct contact between the negative electrode plate 202 and the positive electrode tab 205. The second insulating layer 207 can cover the entire surface or part of the surface of the positive electrode tab 205 exposed in the shell 10.

[0040] In one embodiment, a negative electrode tab 206 is provided at one end of the negative electrode plate 202 close to the shell cover 102 , the negative electrode tab 206 is electrically connected to the shell cover 102 and the shell 101 , and a third insulating layer 208 is provided on the surface of the negative electrode tab 206 exposed in the shell 10 .

[0041] It can be understood that the third insulating layer 208 is used to cover the surface of the negative electrode tab 206 to prevent the negative electrode tab 206 from directly contacting the positive electrode plate 201 . The third insulating layer 208 can cover the entire surface or part of the surface of the negative electrode tab 206 exposed in the shell 10 .

[0042] In one embodiment, a fourth insulating layer 50 is disposed on the surface of the housing cover 102 exposed to the inside of the housing 10 .

[0043] It can be understood that the fourth insulating layer 50 is used to cover the surface of the shell cover 102 to prevent the shell cover 102 from directly contacting the positive electrode plate 201. The fourth insulating layer 50 can cover the entire surface or part of the surface of the shell cover 102 exposed inside the outer shell 10.

[0044] In some embodiments, the pole 30 is disposed through the middle of the shell cover 102 , and the fourth insulating layer 50 is in a ring shape.

[0045] It can be understood that the pole 30 passes through the middle of the shell cover 102, the surface of the shell cover 102 exposed to the shell 10 is annular, and the fourth insulating layer 50 can cover the entire surface of the shell cover 102, and the fourth insulating layer 50 can be annular.

[0046] In one embodiment, the battery cell assembly 20 is wound, and a support rod 204 is disposed at the center of the wound battery cell assembly 20 . The length of the support rod 204 is smaller than the length of the battery cell assembly 20 along the winding axis.

[0047] It is understood that the support rod 204 can be a steel rod or a plastic rod. A hollow space can be preset in the center of the battery cell assembly 20 for setting the support rod 204, and the diameter of the support rod 204 can be flexibly adjusted according to the diameter of the hollow space in the center of the battery cell assembly 20, and the height of the support rod 204 can be flexibly adjusted according to the height of the battery and the battery cell assembly 20.

[0048] In one embodiment, the support rod 204 is a cylinder.

[0049] In a second aspect, an embodiment of the present application provides a method for manufacturing a button battery, comprising:

[0050] A battery cell assembly 20 is provided, the battery cell assembly 20 includes a positive electrode sheet 201, a negative electrode sheet 202 and an insulating separator 203, wherein the insulating separator 203 is located between the positive electrode sheet 201 and the negative electrode sheet 202;

[0051] An insulating spacer layer is provided at the end of the positive electrode sheet 201 and / or the end of the negative electrode sheet 202, and the insulating spacer layer is coated on the end of the positive electrode sheet 201 and / or the end of the negative electrode sheet 202 to separate the end of the positive electrode sheet 201 from the end of the negative electrode sheet 202, thereby obtaining a battery cell assembly 20 formed with an insulating spacer layer;

[0052] The cell assembly 20 with the insulating spacer layer is packaged in a shell to obtain a button battery.

[0053] It can be understood that the insulating spacer layer can be provided by heating or flat pressing, among which the insulating spacer layer formed by heating has a better effect.

[0054] In one embodiment, at least a portion of the insulating diaphragm 203 forms an insulating spacer layer; the insulating spacer layer is coated on the end of the positive electrode plate 201 and / or the end of the negative electrode plate 202, and includes:

[0055] The end of the cell assembly 20 is heated so that the insulating spacer layer is heated and then coated on the end of the positive electrode sheet 201 and / or the end of the negative electrode sheet 202 .

[0056] It can be understood that the insulating separator 203 will soften after heating, so that it can be coated on the ends of the positive electrode sheet 201 and / or the negative electrode sheet 202. After heating, the insulating separator 203 can only coat the ends of the positive electrode sheet 201, or only coat the ends of the negative electrode sheet 202, or coat both the ends of the positive electrode sheet 201 and the ends of the negative electrode sheet 202, or part of the insulating separator 203 can coat the ends of the positive electrode sheet 201, and part of the insulating separator 203 can coat the ends of the positive electrode sheet 201. The length of the insulating separator 203 can be set to exceed the ends of the positive electrode sheet 201 and the negative electrode sheet 202, so that it can easily coat the ends of the positive electrode sheet 201 and the negative electrode sheet 202.

[0057] In one embodiment, the heating temperature is 20-120° C., and the heating time is 1-180 seconds.

[0058] It can be understood that the heating temperature can be 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, etc. The heating time can be 10S, 20S, 30S, 40S, 50S, 60S, 70S, 80S, 90S, 100S, 110S, 120S, 130S, 140S, 150S, 160S, 170S, etc.

[0059] In one embodiment, the battery cell assembly 20 is wound, and before heating the end of the battery cell assembly 20, the method further includes:

[0060] A support rod 204 is provided and disposed at the center of the wound battery cell assembly 20 .

[0061] It is understood that the battery cell assembly 20 can be pre-hollowed in the center during the winding process, so as to facilitate the setting of the support rod 204 in the center of the battery cell assembly 20. The support rod 204 can be added to the center of the battery cell assembly 20 before the battery cell assembly 20 is heated, and can also be added to the center of the battery cell assembly 20 after the battery cell assembly 20 is heated.

[0062] In one embodiment, the battery cell assembly 20 further includes a positive electrode tab 205 disposed at one end of the positive electrode sheet 201 and a negative electrode tab 206 disposed at one end of the negative electrode sheet 202, and the method further includes:

[0063] A second insulating layer 207 is disposed on the surface of the positive electrode tab 205;

[0064] A third insulating layer 208 is disposed on the surface of the negative electrode tab 206 .

[0065] It can be understood that the positive pole tab 205 and the negative pole tab 206 can be connected to the positive pole sheet 201 and the negative pole sheet 202 before the positive pole sheet 201 and the negative pole sheet 202 are wound to form a battery cell assembly. The connection method of the positive pole tab 205 and the negative pole tab 206 to the positive pole sheet 201 and the negative pole sheet 202 can be welding. An insulating layer is provided on the surface of the positive pole tab 205 and the negative pole tab 206, and the positive pole tab 205 and the negative pole tab 206 can be connected to the positive pole sheet 201 and the negative pole sheet 202, so as to facilitate processing. The second insulating layer 207 and the third insulating layer 208 can be provided by sticking insulating layer tape on the positive pole tab and the negative pole tab.

[0066] In one embodiment, the step of encapsulating the cell assembly 20 having the insulating spacer layer into a shell to obtain a button battery includes:

[0067] A housing 10 is provided, the housing 10 comprises a housing cover 102 and a shell 101 sealedly connected to the housing cover 102, a pole 30 is arranged on the housing cover 102, the pole 30 penetrates the housing cover 102 and is electrically insulated from the housing cover 102;

[0068] The end of the positive electrode tab 205 away from the positive electrode sheet 201 is electrically connected to the pole 30, and then a first insulating layer 40 is provided on a side of the pole 30 close to the battery cell assembly 20;

[0069] A fourth insulating layer 50 is disposed on a side of the shell cover 102 close to the battery cell assembly 20, and then an end of the negative electrode tab 206 away from the negative electrode plate 202 is electrically connected to the shell cover 102 and the housing 101;

[0070] The cell assembly 20 with the insulating spacer layer is sealed in the housing 10, and then the electrolyte is injected into the housing 10, and the housing 10 is sealed by welding to obtain a button battery.

[0071] It can be understood that the positive electrode tab 205 and the pole 30 can be connected by welding. The negative electrode tab 206 and the shell cover 102 and the shell 101 can be connected by welding. The first insulating layer 40 and the fourth insulating layer 50 can be set by sticking insulating tape on the pole with the positive electrode tab welded, and sticking the insulating tape on the inner side of the shell cover 102.

[0072] The above is a detailed introduction to the embodiments of the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for technicians in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A button battery, characterized in that: include: A shell, wherein a battery cell assembly is disposed in the shell, wherein the battery cell assembly includes a positive electrode sheet, a negative electrode sheet and an insulating diaphragm, wherein the insulating diaphragm is located between the positive electrode sheet and the negative electrode sheet; An insulating spacer layer, covering the end of the positive electrode sheet and / or the end of the negative electrode sheet, so as to separate the end of the positive electrode sheet from the end of the negative electrode sheet; The housing comprises a shell cover and a shell body sealed with the shell cover, the shell cover is provided with a pole, the pole is passed through the shell cover and is electrically insulated from the shell cover, and a first insulating layer is provided on a surface of the pole close to the battery cell assembly; The battery cell assembly is wound, and a support rod is arranged at the center of the wound battery cell assembly.

2. The button battery according to claim 1, characterized in that: The insulating spacer layer is integrally provided with the insulating diaphragm.

3. The button battery according to claim 1, characterized in that: The end of the insulating separator exceeds the end of the positive electrode sheet and the negative electrode sheet.

4. The button battery according to claim 1, characterized in that: A positive electrode tab is provided at one end of the positive electrode sheet close to the shell cover, the positive electrode tab is electrically connected to the pole, and a second insulating layer is provided on the surface of the positive electrode tab exposed in the shell.

5. The button battery according to claim 1, characterized in that: A negative electrode tab is provided at one end of the negative electrode plate close to the shell cover, the negative electrode tab is electrically connected to the shell cover and the shell, and a third insulating layer is provided on the surface of the negative electrode tab exposed in the shell.

6. The button battery according to claim 1, characterized in that: A fourth insulating layer is disposed on a surface of the shell cover exposed inside the housing.

7. The button battery according to claim 6, characterized in that: The pole is disposed through the middle of the shell cover, and the fourth insulating layer is in a circular ring shape.

8. The button battery according to any one of claims 1 to 4, characterized in that: The length of the support rod is smaller than the length of the battery core assembly along the winding axis.

9. The button battery according to claim 8, characterized in that: The supporting rod is a cylinder.

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