Cover plate structure and battery

Abstract

The utility model relates to the technical field of batteries, and discloses a cover plate structure and a battery, the cover plate structure comprises: a plate body provided with a mounting hole; the polar column is riveted at the mounting hole of the plate body, and a riveting rib and an external connection part are respectively formed on two sides of the polar column on the plate body along the axis direction of the mounting hole; the external connection part is suitable for being electrically connected with an external structure, and the riveting rib is suitable for riveting the pole with the plate body; in the axial direction of the mounting hole, the post terminal is locally sunken from one side of the external connection part to one side of the riveting rib to form a groove part, and a welding part is formed at the bottom of the groove part of the post terminal; the welding part is suitable for being directly welded with the tab. According to the cover plate structure provided by the utility model, a connecting sheet does not need to be arranged between the pole and the tab of the pole group, so that the number of parts is reduced, and the space utilization rate is improved; working procedures in the machining process are reduced, and the reject ratio is reduced.

Description

Technical Field

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

[0002] In the related art, the cover plate of a square battery and the tab of the electrode group are often connected by a connecting piece. The tab needs to be bent and then welded to the connecting piece, and then the connecting piece is welded to the pole column on the cover plate; this results in complex processes, low space utilization rate, a relatively high risk of tab tearing, and a high cost and defective rate due to a large number of components. Summary of the Utility Model

[0003] In view of this, the utility model provides a cover plate structure and a battery to solve the problems of complex processes, low space utilization rate, and relatively high risk of tab tearing caused by connecting the cover plate and the tab by a connecting piece.

[0004] In the first aspect, the utility model provides a cover plate structure, including:

[0005] A plate body, which is provided with a mounting hole;

[0006] A pole column, riveted at the mounting hole of the plate body. Along the axis direction of the mounting hole, the pole column forms a riveting rib and an external connection part on both sides of the plate body respectively; the external connection part is suitable for being electrically connected with an external structure, and the riveting rib is suitable for riveting the pole column and the plate body;

[0007] And along the axis direction of the mounting hole, the pole column is partially recessed from the side of the external connection part towards the side of the riveting rib to form a groove part, and a welding part is formed at the bottom of the pole column where the groove part is located;

[0008] The welding part is suitable for being directly welded to the tab.

[0009] Beneficial effects: In the cover plate structure provided by the embodiment of the utility model, the pole column is riveted at the mounting hole of the plate body. Along the axis direction of the mounting hole, the pole column forms a riveting rib and an external connection part on both sides of the plate body respectively; and along the axis direction of the mounting hole, the pole column is partially recessed from the side of the external connection part towards the side of the riveting rib to form a groove part, and a welding part is formed at the bottom of the pole column where the groove part is located; the welding part is suitable for being directly welded to the tab. Thus, laser welding can be used to make the laser penetrate the welding part and directly weld the welding part to the tab of the electrode group to achieve electrical connection. There is no need to set a connecting piece between the pole column and the tab of the electrode group, thus reducing the number of parts, eliminating the need to reserve the design thickness of the connecting piece, and improving the space utilization rate; at the same time, the number of process steps in the processing process is reduced, the number of error and omission points is reduced, and the defective rate is lowered. Moreover, the welding part can be directly attached to the tab, avoiding the deviation in the assembly of the tab and the pole column, and facilitating the improvement of the welding yield and the assembly effect.

[0010] In an alternative embodiment, along the axial direction of the mounting hole, the projection of the groove portion is within the projection range of the mounting hole.

[0011] Beneficial effects: Along the axial direction of the mounting hole, by making the projection of the groove portion within the projection range of the mounting hole, after the terminal post passes through the mounting hole, the groove portion can be free from interference by the plate body, thereby ensuring that the welding portion can be directly attached to the tab, facilitating laser welding, enabling the laser to penetrate the welding portion, directly welding the welding portion to the tab of the electrode group, and achieving electrical connection.

[0012] In an alternative embodiment, the surface of the welding portion facing the tab is flush with the surface of the riveting rib facing the tab.

[0013] Beneficial effects: By making the surface of the welding portion facing the tab flush with the surface of the riveting rib facing the tab, the contact area at the bottom of the terminal post can be increased, the current-carrying area can be ensured, the matching degree between the terminal post and the tab can be improved, and the assembly and welding of the terminal post and the tab can be facilitated.

[0014] In an alternative embodiment, along the axial direction of the mounting hole, the thickness of the welding portion is S, and 0.4 mm ≤ S ≤ 1.2 mm is satisfied.

[0015] Beneficial effects: By setting the upper limit of the thickness S of the welding portion, the laser can penetrate the welding portion to achieve the welding of the terminal post and the tab. By setting the lower limit of the thickness S of the welding portion, the situation of insufficient connection strength caused by too thin a welding portion can be avoided, and the current-carrying area after welding the terminal post and the tab can be ensured.

[0016] In an alternative embodiment, the terminal post is further recessed to form a counterbore portion, and the counterbore portion is adapted to place an external conductive element;

[0017] In the direction perpendicular to the axial direction of the mounting hole, the cross-sectional area of the counterbore portion is larger than the cross-sectional area of the groove portion;

[0018] And along the axial direction of the mounting hole, the projection of the counterbore portion at least partially overlaps with the projection of the groove portion.

[0019] Beneficial effects: By providing the counterbore portion, the counterbore portion is adapted to place an external conductive element; thereby facilitating the connection between the terminal post and the external conductive element, and the external conductive element is arranged in the counterbore portion, which can reduce the overall height of the battery, so that after assembling to form a battery pack, more space can be saved, and the energy density of the entire battery pack can be improved.

[0020] In a second aspect, the present invention further provides a battery, including:

[0021] A housing, openings are formed at both ends of the housing along the length direction;

[0022] and a cover plate structure as described above, covering the opening of the housing; the cover plate structure and the housing jointly enclose a receiving cavity;

[0023] It further includes: a pole group, disposed in the receiving cavity.

[0024] In an alternative embodiment, a tab is formed on the side of the pole group facing the cover plate structure;

[0025] The tab is made by a flattening process.

[0026] Advantageous effects: For the battery provided by the embodiment of the present utility model, the tab is processed by a flattening process, there is no need to provide a connecting piece between the pole post and the tab, and the tab does not need to be bent, reducing the space occupied by the tab and avoiding the risk of tearing of the tab.

[0027] In an alternative embodiment, the tab is disposed in contact with the welding portion, and the tab is welded to the welding portion, and a weld mark is formed in the welding area; the area of the weld mark is less than or equal to the cross-sectional area of the groove portion in the direction perpendicular to the axis of the mounting hole.

[0028] In an alternative embodiment, the height of the tab protruding from the end face of the pole group facing the cover plate structure is D, and it satisfies: D > S; where S is the thickness of the welding portion in the direction of the axis of the mounting hole.

[0029] Advantageous effects: By setting the height D of the tab protruding from the end face of the pole group facing the cover plate structure to be greater than the thickness S of the welding portion, it is possible to facilitate laser penetration welding of the welding portion and avoid further laser penetration of the tab to damage the pole group, improving safety.

[0030] In an alternative embodiment, the height of the tab protruding from the end face of the pole group facing the cover plate structure is D, and it satisfies: 0.8 mm ≤ D ≤ 2.5 mm.

[0031] Advantageous effects: By setting the upper limit of the height D of the tab protruding from the end face of the pole group facing the cover plate structure, it is possible to avoid material waste caused by the tab being too thick and reduce the space occupied by the tab. At the same time, by setting the lower limit of the height D of the tab protruding from the end face of the pole group facing the cover plate structure, it is possible to avoid further laser penetration of the tab to damage the pole group, improving safety. Description of the Drawings

[0032] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 Schematic diagram of the battery of the present utility model;

[0034] Figure 2 Cross-sectional schematic diagram of the battery of the present utility model;

[0035] Figure 3 is Figure 2 Enlarged view of position A in

[0036] Figure 4 Schematic diagram of the cooperation between the terminal post and the electrode group;

[0037] Figure 5 Schematic diagram of the electrode group of the present utility model;

[0038] Figure 6 Schematic diagram of the cover plate structure of the present utility model;

[0039] Explanation of reference numerals in the drawings:

[0040] 1. Housing; 2. Cover plate structure; 21. Terminal post; 211. Groove portion; 212. Counterbore portion; 213. Riveting rib; 214. Welding portion; 215. External connection portion; 22. Plate body; 221. Mounting hole;

[0041] 3. Electrode group; 31. Tab; 4. External conductive element; 5. Weld mark. Detailed implementation manners

[0042] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0043] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present utility model. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0044] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0045] In addition, the technical features involved in different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0046] The following Figures 1 to 6 is combined to describe the embodiments of the present utility model.

[0047] According to an embodiment of the present utility model, on the one hand, a cover plate structure 2 is provided, including:

[0048] A plate body 22 is provided with an installation hole 221;

[0049] A pole column 21 is riveted at the installation hole 221 of the plate body 22. Along the axial direction of the installation hole 221, the pole column 21 is respectively formed with a riveting rib 213 and an external connection part 215 on both sides of the plate body 22; the external connection part 215 is adapted to be electrically connected to an external structure, and the riveting rib 213 is adapted to rivet the pole column 21 and the plate body 22;

[0050] And along the axial direction of the installation hole 221, the pole column 21 is locally recessed from the side of the external connection part 215 towards the side of the riveting rib 213 to form a groove part 211, and a welding part 214 is formed at the bottom of the pole column 21 where the groove part 211 is located;

[0051] The welding part 214 is adapted to be directly welded to the pole ear 31.

[0052] In this embodiment, the cover plate structure 2 includes a plate body 22, and the plate body 22 covers the opening of the housing 1. The cover plate structure may further include an insulating member. By providing an installation hole 221 on the plate body 22 and riveting the pole column 21 at the installation hole 221 of the plate body 22, the pole column 21 can fixedly connect the various components of the cover plate structure. The pole column 21 penetrates the plate body 22 and is insulated from the plate body 22, so that the pole column 21 can be adapted to connect the pole group inside the battery and the external conductive element 4.

[0053] Combined with Figure 4As shown in the figure, the terminal post 21 of this embodiment is configured in a "work" - shaped structure. Along the axial direction of the mounting hole 221, the terminal post 21 is respectively formed with riveting ribs 213 and external connection parts 215 on both sides of the plate body 22; among them, the external connection part 215 is suitable for being electrically connected to the external conductive element 4, and specifically, the conduction between the external connection part 215 and the external conductive element 4 can be realized by means such as welding or screwing. The riveting ribs 213 are suitable for riveting the terminal post 21 to the plate body 22; in the specific production process of the battery, before the terminal post 21 is inserted into the mounting hole 221 of the plate body 22, the extending direction of the riveting ribs 213 can be parallel to the axial direction of the mounting hole 221, so as to facilitate the insertion of the terminal post 21 into the mounting hole 221 of the plate body 22 and avoid interference of the riveting ribs 213; after the terminal post 21 is inserted into the mounting hole 221 of the plate body 22, the riveting ribs 213 are folded by rolling, and then the extending direction of the riveting ribs 213 is perpendicular to or at an angle with the axial direction of the mounting hole 221, so as to prevent the riveting ribs 213 of the terminal post 21 from coming out of the mounting hole 221 of the plate body 22 and realize the riveting of the terminal post 21 to the plate body 22.

[0054] Combined Figure 4 As shown in the figure, and along the axial direction of the mounting hole 221, a groove part 211 is locally recessed from the side of the external connection part 215 towards the side of the riveting ribs 213 of the terminal post 21. By providing the groove part 211, the thickness of the terminal post 21 can be reduced, so that a welding part 214 is formed at the bottom of the groove part 211 of the terminal post 21; so as to enable laser welding, make the laser penetrate the welding part 214, and directly weld the welding part 214 to the tab 31 of the electrode group 3 to realize electrical connection.

[0055] The cover plate structure provided by the embodiment of the present utility model rivets the terminal post 21 at the mounting hole 221 of the plate body 22. Along the axial direction of the mounting hole 221, the terminal post 21 is respectively formed with riveting ribs 213 and external connection parts 215 on both sides of the plate body 22; and along the axial direction of the mounting hole 221, a groove part 211 is locally recessed from the side of the external connection part 215 towards the side of the riveting ribs 213 of the terminal post 21, and a welding part 214 is formed at the bottom of the groove part 211 of the terminal post 21; the welding part 214 is suitable for directly welding to the tab 31. Thus, laser welding can be used to make the laser penetrate the welding part 214 and directly weld the welding part 214 to the tab 31 of the electrode group 3 to realize electrical connection. There is no need to set a connecting piece between the terminal post 21 and the tab of the electrode group, thus reducing the number of parts, without reserving the design thickness of the connecting piece, improving the space utilization rate; at the same time, reducing the process steps in the processing process, reducing the error - prone points and reducing the defective rate. And, the welding part 214 can directly fit with the tab 31, avoiding the deviation in the assembly of the tab 31 and the terminal post 21, facilitating the improvement of the welding yield and the assembly effect.

[0056] In this embodiment, both the welding portion 214 and the riveting rib 213 are provided on the side of the pole column 21 close to the pole ear 31; in combination with Figure 4 as shown, that is, the bottom of the "I"-shaped structure, so as to facilitate the fitting of the pole column 21 and the pole ear 31 and ensure sufficient contact area.

[0057] In some embodiments, in combination with Figure 3 as shown, along the axial direction of the mounting hole 221, the projection of the groove portion 211 is within the projection range of the mounting hole 221.

[0058] Along the axial direction of the mounting hole 221, by making the projection of the groove portion 211 within the projection range of the mounting hole 221, after the pole column 21 passes through the mounting hole 221, the groove portion 211 can be free from the interference of the plate body 22, and further ensure that the welding portion 214 can be directly fitted with the pole ear 31, facilitating laser welding, enabling the laser to penetrate the welding portion 214, directly welding the welding portion 214 with the pole ear 31 of the pole group 3, and realizing electrical connection.

[0059] In some embodiments, in combination with Figure 4 as shown, the surface of the welding portion 214 facing the pole ear 31 is flush with the surface of the riveting rib 213 facing the pole ear 31.

[0060] By making the surface of the welding portion 214 facing the pole ear 31 flush with the surface of the riveting rib 213 facing the pole ear 31, the contact area at the bottom of the pole column 21 can be increased, the current-carrying area can be ensured, the matching degree between the pole column 21 and the pole ear 31 can be improved, and the assembly and welding of the pole column 21 and the pole ear 31 can be facilitated.

[0061] In some embodiments, in combination with Figure 4 as shown, along the axial direction of the mounting hole 221, the thickness of the welding portion 214 is S, and 0.4 mm ≤ S ≤ 1.2 mm is satisfied.

[0062] As an optional implementation form, the value of the thickness S of the welding portion 214 can be 0.4 mm or 0.5 mm or 0.6 mm or 0.7 mm or 0.8 mm or 1 mm or 1.1 mm or 1.2 mm, etc.

[0063] In this embodiment, the thickness of the welding portion 214 specifically refers to the thickness between the bottom of the groove portion 211 and the bottom of the pole column 21 along the axial direction of the mounting hole 221.

[0064] By setting the upper limit of the thickness S of the welding portion 214, it can ensure that the laser penetrates the welding portion 214 to realize the welding of the pole column 21 and the pole ear 31. And by setting the lower limit of the thickness S of the welding portion 214, it can avoid the situation of insufficient connection strength caused by the too thin thickness of the welding portion 214, and at the same time ensure the current-carrying area after the welding of the pole column 21 and the pole ear 31.

[0065] In some embodiments, in combination with Figure 4 As shown, a counterbore portion 212 is further recessed in the terminal post 21, and the counterbore portion 212 is adapted to place an external conductive element 4;

[0066] In a direction perpendicular to the axis of the mounting hole 221, the cross-sectional area of the counterbore portion 212 is larger than the cross-sectional area of the groove portion 211;

[0067] And along the axis direction of the mounting hole 221, at least a part of the projection of the counterbore portion 212 overlaps with the projection of the groove portion 211.

[0068] By providing the counterbore portion 212, the counterbore portion 212 is adapted to place the external conductive element 4; thereby facilitating the connection between the terminal post 21 and the external conductive element 4, and the external conductive element 4 is arranged in the counterbore portion 212, which can reduce the overall height of the battery, so that after assembling the battery pack, more space can be saved, and the energy density of the whole battery pack can be improved.

[0069] According to an embodiment of the present invention, on the other hand, a battery is further provided, including:

[0070] A housing 1, with openings formed at both ends of the housing 1 along the length direction;

[0071] And the cover plate structure 2 as described above, covering the opening of the housing 1; the cover plate structure and the housing 1 jointly enclose a receiving cavity;

[0072] It further includes: a pole group 3, arranged in the receiving cavity.

[0073] The length of the battery along the length direction is L, satisfying: L≥300mm.

[0074] The battery provided by the embodiment of the present utility model rivets the pole column 21 at the installation hole 221 of the plate body 22. Along the axial direction of the installation hole 221, the pole column 21 is respectively formed with a riveting rib 213 and an external connection part 215 on both sides of the plate body 22; and along the axial direction of the installation hole 221, the pole column 21 is locally recessed from the side of the external connection part 215 towards the side of the riveting rib 213 to form a groove part 211, and a welding part 214 is formed at the bottom of the pole column 21 where the groove part 211 is located; the welding part 214 is suitable for directly welding with the pole tab 31. Thus, through laser welding, the laser can penetrate the welding part 214 to directly weld the welding part 214 with the pole tab 31 of the pole group 3 to achieve electrical connection. There is no need to set a connecting piece between the pole column 21 and the pole tab of the pole group, thereby reducing the number of parts, eliminating the need to reserve the design thickness of the connecting piece, and improving the space utilization rate; at the same time, the process steps in the processing process are reduced, the error and omission points are reduced, and the defective rate is lowered. Moreover, the welding part 214 can directly fit with the pole tab 31, avoiding the deviation in the assembly of the pole tab 31 and the pole column 21, which is convenient for improving the welding yield and the assembly effect.

[0075] The embodiment of the present utility model is applicable to a battery with pole tabs protruding from both ends of the pole group. The two pole tabs are respectively a positive pole tab and a negative pole tab, and the connection form between the two pole tabs and the cover plate structure both adopts the form of directly welding the welding part 214 with the pole tab 31, thereby improving the assembly efficiency and the space utilization rate.

[0076] In some embodiments, as shown in Figure 5 a pole tab 31 is formed on one side of the pole group 3 facing the cover plate structure;

[0077] The pole tab 31 is made by a flattening process.

[0078] For the battery provided by the embodiment of the present utility model, the pole tab 31 is processed by a flattening process. There is no need to set a connecting piece between the pole column 21 and the pole tab 31, and the pole tab 31 does not need to be bent, reducing the space occupied by the pole tab 31 and avoiding the risk of tearing of the pole tab 31.

[0079] In some embodiments, as shown in Figure 3 the pole tab 31 is arranged in a fitting manner with the welding part 214, and the pole tab 31 is welded to the welding part 214, and a welding mark 5 is formed in the welding area; the area of the welding mark 5 is less than or equal to the cross-sectional area of the groove part 211 in the direction perpendicular to the axial direction of the installation hole 221.

[0080] Since the laser needs to penetrate the welding part 214 for welding, and the welding part 214 is formed at the bottom of the groove part 211, that is, the area of the groove part 211 defines the welding area. In this embodiment, the size of the groove part 211 is determined by the capacity and rate of the product.

[0081] In some embodiments, as shown in Figure 4As shown, the height of the tab 31 protruding from the end face of the electrode group 3 towards the cover plate structure is D, and it satisfies: D > S; where S is the thickness of the welding part 214 along the axis direction of the mounting hole 221.

[0082] By setting the height D of the tab 31 protruding from the end face of the electrode group 3 towards the cover plate structure to be greater than the thickness S of the welding part 214, it is convenient for the laser to penetrate the welding part 214 for welding, and it can avoid the laser from further penetrating the tab 31 and causing damage to the electrode group, thus improving safety.

[0083] In some embodiments, in combination with Figure 4 As shown, the height of the tab 31 protruding from the end face of the electrode group 3 towards the cover plate structure is D, and it satisfies: 0.8 mm ≤ D ≤ 2.5 mm.

[0084] As an optional implementation form, the value of the height D of the tab 31 protruding from the end face of the electrode group 3 towards the cover plate structure can be 0.8 mm or 1 mm or 1.2 mm or 1.5 mm or 1.7 mm or 2 mm or 2.2 mm or 2.3 mm or 2.4 mm or 2.5 mm, etc.

[0085] By setting the upper limit of the height D of the tab 31 protruding from the end face of the electrode group 3 towards the cover plate structure, it can avoid material waste caused by the tab 31 being too thick and reduce the space occupied by the tab 31. At the same time, by setting the lower limit of the height D of the tab 31 protruding from the end face of the electrode group 3 towards the cover plate structure, it can avoid the laser from further penetrating the tab 31 and causing damage to the electrode group, thus improving safety.

[0086] Obviously, the above embodiments are only examples for clear illustration and not limitations on the implementation manners. Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A cover plate structure, characterized in that: include: The plate body (22) is provided with a mounting hole (221); A pole (21) is riveted to the mounting hole (221) of the plate body (22); along the axial direction of the mounting hole (221), riveting ribs (213) and external connection parts (215) are respectively formed on both sides of the pole (21) located on the plate body (22); the external connection part (215) is suitable for being electrically connected to an external structure, and the riveting ribs (213) are suitable for riveting the pole (21) to the plate body (22); Furthermore, along the axial direction of the mounting hole (221), the pole (21) is partially recessed from one side of the external connection portion (215) toward one side of the rivet rib (213) to form a groove portion (211), and the pole (21) is formed with a welding portion (214) at the bottom of the groove portion (211); The welding portion (214) is suitable for being directly welded to the pole tab (31).

2. The cover plate structure according to claim 1, characterized in that: Along the axial direction of the mounting hole (221), the projection of the groove portion (211) is located within the projection range of the mounting hole (221).

3. The cover plate structure according to claim 1, characterized in that: A surface of one side of the welding portion (214) facing the pole lug (31) is flush with a surface of one side of the rivet rib (213) facing the pole lug (31).

4. The cover plate structure according to any one of claims 1 to 3, characterized in that: Along the axial direction of the mounting hole (221), the thickness of the welding portion (214) is S, and satisfies 0.4 mm ≤ S ≤ 1.2 mm.

5. The cover plate structure according to any one of claims 1 to 3, characterized in that: The pole (21) is also recessed to form a recessed platform (212), and the recessed platform (212) is suitable for placing an external conductive element (4); In a direction perpendicular to the axis of the mounting hole (221), the cross-sectional area of ​​the recessed portion (212) is greater than the cross-sectional area of ​​the recessed portion (211); Furthermore, along the axial direction of the mounting hole (221), the projection of the recessed platform portion (212) at least partially overlaps with the projection of the recessed groove portion (211).

6. A battery, characterized in that: include: A shell (1), wherein openings are formed at both ends of the shell (1) along the length direction; And the cover plate structure as described in any one of claims 1 to 5 above, which is covered at the opening of the shell (1); the cover plate structure and the shell (1) together enclose a receiving cavity; It also includes: a pole group (3) arranged in the accommodating cavity.

7. The battery according to claim 6, characterized in that A pole ear (31) is formed on one side of the pole group (3) facing the cover plate structure; The pole lug (31) is made by a flattening process.

8. The battery according to claim 7, characterized in that The pole lug (31) and the welding portion (214) are arranged in close contact with each other, and the pole lug (31) and the welding portion (214) are welded to each other, and a weld mark (5) is formed in the welding area; the area of ​​the weld mark (5) is less than or equal to the cross-sectional area of ​​the groove portion (211) in a direction perpendicular to the axis of the mounting hole (221).

9. The battery according to claim 7, characterized in that The height of the pole lug (31) protruding from the pole group (3) toward the end surface of the cover plate structure is D, and satisfies: D>S; wherein S is the thickness of the welding portion (214) along the axial direction of the mounting hole (221).

10. The battery according to claim 9, characterized in that The height of the pole lug (31) protruding from the end surface of the pole group (3) toward the cover plate structure is D, and satisfies the following: 0.8 mm ≤ D ≤ 2.5 mm.

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