Battery structure

Abstract

A battery structure, comprising: a case (1); and an electrode group (3) provided in the case; a cover plate (2) covering the opening of the case so as to seal the electrode group in the case; a tab (4) extending from at least one side end surface of the electrode group, the tab being electrically connected to a pole (21), and the pole being arranged on the case or the cover plate; and a supporting assembly (5) arranged in the case, the supporting assembly abutting against the tab, so that at least part of the tab is directly or indirectly attached to the inner surface of the case and / or the inner surface of the cover plate.

Description

Battery structure

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on September 28, 2023, with application number 202311284966.8 and invention name “Battery Structure”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the technical field of battery devices, and in particular to a battery structure. Background Art

[0004] High-rate fast charging of batteries has gradually become a market trend. However, the problem brought about by fast charging is increased heat generation. Taking square battery cells as an example, the internal electrode group and the electrode cover are generally connected by the tab and the current collector. Under high-rate fast charging scenarios, the connection between the tab and the current collector is prone to high temperatures. The main reason is that the main heat transfer path at this location is from the tab to the electrode group and from the current collector to the electrode. The long heat transfer path is not easy to dissipate heat, making it difficult to support high-rate, high-current fast charging.

[0005] Summary of the Invention

[0006] In view of this, the present application provides a battery structure to solve the problem of poor heat dissipation at the tab position.

[0007] The present application provides a battery structure, comprising:

[0008] case;

[0009] The electrode group is arranged in the shell;

[0010] A cover plate is provided at the opening of the shell to seal the electrode group in the shell;

[0011] The pole tab is formed by extending from at least one end surface of the pole group. The pole tab is electrically connected to the pole post, which is provided on the housing or cover plate.

[0012] The support assembly is arranged in the shell and abuts against the tab so that at least a portion of the tab is directly or indirectly in contact with the inner surface of the shell and / or the inner surface of the cover plate.

[0013] Beneficial Effects: The battery structure provided by this application, by disposing a support assembly within the housing and abutting the support assembly against the tab, allows the tab to at least partially contact the inner surface of the housing or the inner surface of the cover plate, directly or indirectly. This allows heat from the tab to be transferred to the housing, facilitating heat dissipation from the tab, facilitating high-rate and high-current operating conditions, and improving the heat dissipation performance of the battery structure. This allows the tab to transfer heat directly to the housing, reducing the need for heat dissipation from the tab to the electrode assembly, shortening the heat transfer path, and improving the heat dissipation efficiency of the tab.

[0014] In an optional embodiment, it further includes: an insulating heat-conducting member, which is arranged between the inner surface of the pole tab and the shell, and / or between the inner surface of the pole tab and the cover plate.

[0015] Beneficial Effects: The insulating thermal conductive member is made of an insulating material. By providing insulation, short circuits between the tab and the housing, or between the tab and the cover, can be avoided. By making the insulating thermal conductive member inherently insulating, the use of separate insulating materials is reduced, thus reducing the overall weight of the battery structure.

[0016] In an optional embodiment, the tab is bent to form a groove, and the support assembly is arranged in the groove formed by the bending of the tab;

[0017] At least one outer surface of the support assembly is arranged in contact with the tab.

[0018] Beneficial Effects: By bending the tab to form a groove, the support assembly is positioned within the groove formed by the bent tab, which can stretch the tab so that the tab fits securely with the inner surface of the housing and / or the inner surface of the cover plate, ensuring a secure fit and improving heat dissipation efficiency. Furthermore, at least one outer surface of the support assembly is positioned in contact with the tab, further increasing the contact area between the support assembly and the tab, thereby improving heat dissipation efficiency.

[0019] In an optional embodiment, the electrode tab includes a lead portion connected to the electrode group and a connecting portion connected to the electrode column, and a bending portion is formed between the lead portion and the connecting portion;

[0020] The bent portion is arranged along the thickness direction of the battery structure close to the inner surface of the second side of the shell.

[0021] Beneficial effect: By arranging the bent portion close to the inner surface of the second side of the shell along the thickness direction of the battery structure, it is convenient for the support component to squeeze the pole ear so that more areas of the pole ear are in contact with the inner surface of the shell and / or the inner surface of the cover plate, thereby improving the heat dissipation efficiency.

[0022] In an optional embodiment, along the thickness direction of the battery structure, the support assembly has a second support surface abutting against the bent portion, and a first support surface abutting against the inner surface of the first side of the shell;

[0023] And / or, the tab is formed by stacking a plurality of single tabs, and as the single tabs are stacked, after the lead portion is formed on the tab, it is suitable for the lead portion to be inclined along the thickness direction;

[0024] And / or, the support assembly is further formed with an inclined guide surface that fits the lead-out portion, and the angle between the inclined guide surface and the second support surface is β, wherein β satisfies: 90°<β<180°.

[0025] Beneficial Effects: By forming an inclined guide surface on the support assembly that mates with the lead portion, the support assembly can be fitted to the tab, increasing the contact area and ensuring uniform heat dissipation. This also prevents excessive compression of the tab by the support assembly, preventing local tab breakage.

[0026] In an optional embodiment, the support assembly includes: a support shell and an inner core filled in the support shell;

[0027] The supporting shell is made of thermally conductive flexible material, and the inner core is made of elastic material;

[0028] Wherein, the material of the supporting shell includes graphene or boron nitride;

[0029] The inner core material includes foam;

[0030] When the supporting shell is graphene, the outer surface of the supporting shell is also covered with an insulating film.

[0031] Beneficial Effects: By making the support assembly a composite of multiple materials and coating the inner core with a support shell made of graphene or boron nitride, heat dissipation can be improved and good conductivity can be ensured. Furthermore, by making the inner core of foam, the flexible deformation of the foam can be utilized to achieve a better fit between the support assembly and the tab, increasing the contact area and ensuring uniform heat dissipation.

[0032] In an optional embodiment, the support assembly includes: a support shell and an inner core filled in the support shell;

[0033] The supporting shell is made of insulating sealing material;

[0034] The inner core is made of phase change material and is sealed inside the supporting shell;

[0035] The material of the inner core includes paraffin wax.

[0036] Beneficial effect: By making the inner core from phase change material, the high specific heat capacity of the phase change material can be utilized to quickly absorb the heat generated by the tabs, thereby accelerating the heat dissipation efficiency.

[0037] In an optional embodiment, the tab is provided on the tab lead-out surface of the electrode group;

[0038] Along the long side parallel to the tab lead surface, the length of the tab is W and satisfies:

[0039] W>0.3H, where H is the length of the tab lead surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0041] FIG1 is a perspective schematic diagram of the battery structure of the present application;

[0042] FIG2 is a schematic cross-sectional view of the battery structure of the present application;

[0043] Figure 3 is an enlarged view of point A in Figure 2;

[0044] FIG4 is an exploded schematic diagram of the battery structure of the present application;

[0045] FIG5 is an enlarged view of point A in FIG2.

[0046] Explanation of the accompanying drawings: 1. Shell; 11. Explosion-proof unit; 2. Cover plate; 21. Pole; 3. Pole group; 31. Tab lead-out surface; 4. Tab; 41. Lead-out portion; 42. Connecting portion; 43. Bending portion; 5. Support assembly; 51. Support shell; 511. First supporting surface; 512. Second supporting surface; 513. Inclined guide surface; 52. Inner core; 7. Insulating thermal conductor. DETAILED DESCRIPTION

[0047] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of this application.

[0048] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0050] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0051] The following describes an embodiment of the present application in conjunction with FIG. 1 to FIG. 4 .

[0052] According to an embodiment of the present application, a battery structure is provided, including:

[0053] Shell 1;

[0054] The pole group 3 is arranged in the housing 1;

[0055] The cover plate 2 is provided at the opening of the housing 1 to seal the electrode group 3 in the housing 1;

[0056] The pole tab 4 is formed by extending from at least one end surface of the pole group 3. The pole tab 4 is electrically connected to the pole post 21. The pole post 21 is provided on the housing 1 or the cover plate 2.

[0057] The support assembly 5 is disposed in the housing 1 and abuts against the tab 4 so that at least a portion of the tab 4 is directly or indirectly in contact with the inner surface of the housing 1 and / or the inner surface of the cover plate 2 .

[0058] This embodiment uses a prismatic battery as an example. The housing 1 encloses four sides, with an opening formed at one end or at both ends along the length of the battery structure. A cover plate 2 is placed over the opening in the housing 1 and sealed to the housing 1, thereby enclosing the electrode assembly 3 within the housing 1.

[0059] A pole tab 4 is formed extending from at least one end surface of the pole group 3 . In this embodiment, the pole group 3 has two pole tabs 4 , namely a positive pole tab and a negative pole tab.

[0060] The electrode tab 4 is electrically connected to the electrode post 21 , so that the electrode group 3 is connected to the external circuit for charging and discharging.

[0061] Optionally, the pole lug 4 is connected to the pole post 21 by welding.

[0062] Optionally, the pole 21 is provided on the housing 1 or the cover plate 2 .

[0063] The battery structure provided by the embodiment of the present application is provided with a support assembly 5 within the housing 1, so that the support assembly 5 abuts against the tab 4, so that the tab 4 is at least partially in direct or indirect contact with the inner surface of the housing 1 or the inner surface of the cover plate 2, thereby enabling heat from the tab 4 to be transferred to the housing 1, facilitating heat dissipation from the tab 4, and facilitating the use of high-rate and high-current operating conditions, thereby improving the heat dissipation performance of the battery structure. The ability to directly transfer heat from the tab 4 to the housing 1 reduces the need for the tab 4 to conduct heat dissipation to the electrode group 3, shortens the heat transfer path, and improves the heat dissipation efficiency of the tab 4.

[0064] At the same time, by quickly dissipating the heat of the tab 4, high temperature can be avoided inside the battery structure, the temperature curve inside the battery structure can be smoother, the service life of the electrode group can be improved, the melting of plastic parts caused by high temperature can be avoided, and the internal short circuit of the battery structure caused by excessive melting can be prevented, thereby improving the safety of the battery structure.

[0065] The tab 4 may be directly bonded to the inner surface of the housing 1 or the inner surface of the cover plate 2 , or may be indirectly bonded by providing a heat conducting member.

[0066] Since the tab 4 is conductive, the tab 4 and the housing 1 need to be insulated at their joints to avoid short circuits. Similarly, the tab 4 and the cover plate 2 need to be insulated at their joints to avoid short circuits.

[0067] In some embodiments, as shown in Figure 3, the battery structure also includes: an insulating heat-conducting member 7, which is arranged between the inner surface of the pole tab 4 and the shell 1, and / or the insulating heat-conducting member 7 is arranged between the inner surface of the pole tab 4 and the cover plate 2.

[0068] The insulating heat-conducting member 7 is made of an insulating material. By providing insulation, a short circuit between the tab 4 and the housing 1 or between the tab 4 and the cover 2 can be avoided. By making the insulating heat-conducting member 7 itself insulating, the use of separate insulating materials can be reduced, thereby reducing the overall weight of the battery structure.

[0069] Optionally, the insulating heat conductive member 7 is made of a heat conductive material, which can form a better contact surface between the tab 4 and the shell 1 to achieve a more effective heat conduction path; or, form a better contact surface between the tab 4 and the cover plate 2 to achieve a more effective heat conduction path.

[0070] Optionally, the insulating heat-conducting member 7 may be made of a thermally conductive pad, thermally conductive paste, thermally conductive glue or other materials.

[0071] In some embodiments, as shown in FIG3 , the tab 4 is bent to form a groove, and the support assembly 5 is disposed in the groove formed by the bending of the tab 4 ;

[0072] At least one outer surface of the support assembly 5 is arranged in contact with the tab 4 .

[0073] By bending the tab 4 to form a groove, the support assembly 5 is arranged in the groove formed by the bending of the tab 4, which can stretch the tab 4 so that the tab 4 fits with the inner surface of the shell 1 and / or the inner surface of the cover plate 2, ensuring a firm fit and improving the heat dissipation efficiency.

[0074] At the same time, at least one outer surface of the support assembly 5 is arranged in contact with the tab 4 , which can further increase the contact area between the support assembly 5 and the tab 4 and improve the heat dissipation efficiency.

[0075] Optionally, multiple outer surfaces of the support assembly 5 corresponding to the tab 4 are all arranged in contact with the tab 4, thereby ensuring that heat can be dissipated uniformly in all areas of the tab 4, thereby improving the heat conduction effect of the tab 4 in a limited space.

[0076] Because the tabs 4 are composed of a plurality of stacked individual tabs, as the tabs are stacked, to ensure that the tabs 4 are positioned close to the inner surface of the second side of the housing 1 along the thickness of the battery structure, the multiple individual tabs need to be tilted toward the second side of the housing 1. Furthermore, because the tabs 4 need to be welded to the posts 21, they naturally form a groove after being formed. Therefore, by placing the support assembly 5 within the groove formed by the bending of the tabs 4, the kneading of the tabs 4 can be effectively utilized, facilitating welding of the tabs 4 to the cover plate 2 while also increasing the heat dissipation area of ​​the tabs 4.

[0077] In some embodiments, as shown in FIG5 , the tab 4 includes a lead portion 41 connected to the pole group 3 and a connection portion 42 connected to the pole 21 , and a bent portion 43 is formed between the lead portion 41 and the connection portion 42 ;

[0078] The bent portion 43 is disposed along the thickness direction of the battery structure close to the inner surface of the second side of the housing 1 .

[0079] By arranging the bending portion 43 close to the inner surface of the second side of the shell 1 along the thickness direction of the battery structure, it is convenient for the support component 5 to extrude the pole ear 4 so that more areas of the pole ear 4 are in contact with the inner surface of the shell 1 and / or the inner surface of the cover plate 2, thereby improving the heat dissipation efficiency.

[0080] In some embodiments, as shown in FIG5 , along the thickness direction of the battery structure, the support assembly 5 has a second support surface 512 abutting against the bent portion 43 , and a first support surface 511 abutting against the inner surface of the first side of the housing 1 ;

[0081] The tab 4 is formed by stacking a plurality of single tabs. As the tabs are stacked, the tab 4 forms a lead portion 41, which is adapted to be inclined along the thickness direction.

[0082] The support assembly 5 is further formed with an inclined guide surface 513 that fits with the lead-out portion 41 . The angle between the inclined guide surface 513 and the second support surface 512 is β, where β satisfies: 90°<β<180°.

[0083] By forming the support assembly 5 with an inclined guide surface 513 that mates with the lead portion 41, the support assembly 5 can be fitted with the tab 4, thereby increasing the contact area and ensuring uniform heat dissipation. At the same time, the support assembly 5 can be prevented from excessively squeezing the tab 4, thereby preventing local tab breakage.

[0084] In some embodiments, as shown in FIG4 , the support assembly 5 includes: a support shell 51 and an inner core 52 filled in the support shell 51 ;

[0085] The supporting shell 51 is made of a thermally conductive flexible material, and the inner core 52 is made of an elastic material;

[0086] The material of the support shell 51 includes graphene or boron nitride;

[0087] The material of the inner core 52 includes foam;

[0088] When the supporting shell 51 is graphene, the outer surface of the supporting shell 51 is further covered with an insulating film.

[0089] By making the support assembly 5 from a composite of multiple materials, and coating the inner core 52 with a support shell 51, where the support shell 51 is made of graphene or boron nitride, heat dissipation can be improved and good conductivity can be ensured. Furthermore, by making the inner core 52 from foam, the flexible deformation of the foam can be utilized to achieve a better fit between the support assembly 5 and the tab 4, increasing the contact area and ensuring uniform heat dissipation.

[0090] When the support shell 51 is made of graphene, since graphene has conductive properties, an insulating film needs to be coated on the outer surface of the support shell 51 to prevent the tab 4 from being short-circuited with the shell 1 .

[0091] As a modified embodiment, the support assembly 5 includes: a support shell 51 and an inner core 52 filled in the support shell 51;

[0092] The supporting shell 51 is made of insulating sealing material;

[0093] The inner core 52 is made of phase change material and is sealed inside the supporting shell 51;

[0094] The material of the inner core 52 includes paraffin.

[0095] By making the inner core 52 from a phase change material, the high specific heat capacity of the phase change material can be utilized to quickly absorb the heat generated by the tab, thereby increasing the heat dissipation efficiency.

[0096] When the inner core 52 is made of paraffin wax, since paraffin wax melts when heated, the support shell 51 needs to be made of an insulating sealing material to seal the paraffin wax inside the support shell 51 to prevent it from flowing out, while also facilitating the inward transfer of heat from the support shell 51. In this case, the support shell 51 can also be made of a thermally conductive material to improve the thermal conductivity of the support shell 51 to the tab 4.

[0097] In some embodiments, as shown in FIG4 , the tab 4 is disposed on the tab lead-out surface 31 of the electrode group 3 ;

[0098] Along the long side parallel to the tab lead-out surface 31, the length W of the tab 4 satisfies:

[0099] W>0.3H, where H is the length of the tab lead surface 31 .

[0100] In order to achieve a better heat conduction effect, by ensuring the length of the tab 4 , the tab 4 can have a larger heat dissipation area.

[0101] In some embodiments, as shown in FIG. 1 , the battery structure further includes an explosion-proof unit 11 . The explosion-proof unit 11 is not disposed on the same housing 1 or cover plate 2 as the pole 21 .

[0102] The explosion-proof unit 11 may specifically be an explosion-proof valve.

[0103] By not providing the explosion-proof unit 11 and the pole 21 on the same housing 1 or cover 2 at the same time, it can be ensured that the explosion-proof unit 11 and the pole 21 are not on the same surface, so that the pole lug 4 is independently arranged on the surface of one side, which helps to make the pole lug 4 larger in size to ensure heat dissipation efficiency.

[0104] The pole 21 includes a positive pole and a negative pole; as an implementation form, the positive pole and the negative pole are not in the same plane, thereby ensuring that a single surface of the battery structure has a single output pole, so that the corresponding pole lug 4 can be made larger. For example, in this embodiment, the positive pole and the negative pole are respectively located at the two ends of the pole group 3 along the length direction, that is, the two faces with the shortest edges of the battery structure. As another implementation form, the positive pole and the negative pole are arranged in the same plane. For example, the positive pole and the negative pole can be simultaneously arranged on the surface formed by the longest edge of the battery structure. The length of the pole lugs corresponding to the positive pole and the negative pole are both less than half of the longest edge. In this case, the length of the pole lug 4 can also be guaranteed.

[0105] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Although the embodiments of the present application are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations are all within the scope defined in the present application.

Claims

1. A battery structure, characterized in that: include: case; A pole group is arranged in the shell; A cover plate, which is arranged at the opening of the shell to seal the electrode group in the shell; A pole ear, formed by extending from at least one end surface of the pole group, the pole ear is electrically connected to a pole, and the pole is arranged on the housing or the cover plate; A support assembly is disposed in the shell, and the support assembly abuts against the pole lug, so that at least a portion of the pole lug is directly or indirectly in contact with the inner surface of the shell and / or the inner surface of the cover plate.

2. The battery structure according to claim 1, characterized in that: Also includes: The insulating heat-conducting member is arranged between the inner surface of the pole ear and the shell body, and / or between the inner surface of the pole ear and the cover plate.

3. The battery structure according to claim 1, characterized in that: The tab is bent to form a groove, and the support assembly is arranged in the groove formed by the bending of the tab; At least one outer surface of the support assembly is disposed in contact with the tab.

4. The battery structure according to claim 3, characterized in that: The pole lug includes a lead-out portion connected to the pole group and a connecting portion connected to the pole column, and a bending portion is formed between the lead-out portion and the connecting portion; The bent portion is disposed along the thickness direction of the battery structure close to the inner surface of the second side of the shell.

5. The battery structure according to claim 4, characterized in that: Along the thickness direction of the battery structure, the support assembly has a second support surface abutting against the bent portion, and a first support surface abutting against the inner surface of the first side of the shell; And / or, the tab is formed by stacking a plurality of single tabs, and as the single tabs are stacked, after the lead-out portion is formed, the tab is adapted to be inclined in the thickness direction; And / or, the support assembly is further formed with an inclined guide surface that fits the lead-out portion, and the angle between the inclined guide surface and the second support surface is β, wherein β satisfies: 90°<β<180°.

6. The battery structure according to any one of claims 1 to 5, characterized in that: The support assembly comprises: a support shell and an inner core filled in the support shell; The supporting shell is made of a heat-conductive flexible material, and the inner core is made of an elastic material.

7. The battery structure according to claim 6, characterized in that: The material of the support shell includes graphene or boron nitride; the material of the inner core includes foam; When the supporting shell is graphene, the outer surface of the supporting shell is also covered with an insulating film.

8. The battery structure according to any one of claims 1 to 5, characterized in that: The support assembly comprises: a support shell and an inner core filled in the support shell; The supporting shell is made of insulating sealing material; The inner core is made of phase change material and is sealed inside the supporting shell.

9. The battery structure according to claim 8, characterized in that: The material of the inner core includes paraffin.

10. The battery structure according to any one of claims 1 to 5, characterized in that: The pole lug is arranged on the pole lug lead-out surface of the pole group; Along the long side parallel to the lead-out surface of the tab, the length of the tab is W and satisfies: W>0.3H, wherein H is the length of the lead-out surface of the tab.

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