Battery cell and battery pack
By setting an insulator between the pole group of the battery cell and the connecting piece, the problem of internal short circuit of the battery cell caused by the easy deformation of the connecting piece and damage to the diaphragm is solved, and the safety of the battery is improved.
Patent Information
- Application Number
- CN202422106486.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-08-28
AI Technical Summary
The internal short circuit of the battery cell in the battery is often an important reason for the safety failure of the battery, mainly because the connecting plate is prone to deforming and damage the diaphragm in the pole group.
By providing an insulator between the electrode group and the connecting sheet of the first cover plate assembly, the first through-hole of the insulator can achieve the connection between the electrode group and the connecting sheet, thereby achieving an electrical connection between the electrode group and the first pole through the connecting sheet. The insulating member is disposed between the connecting sheet and the pole group to prevent the connecting sheet from deforming and damaging the diaphragm.
It effectively prevents the connecting plate from deforming and damaging the diaphragm, reduces and even eliminates the internal short circuit of the battery cell, and improves the safety of the battery.
Smart Images
Figure CN222995590U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, and in particular to a battery core and a battery pack. Background Art
[0002] Internal short circuits in battery cells are often an important cause of battery safety failure. In some technical solutions, the electrode group in the battery cell is connected to the connecting piece, and the connecting piece is electrically connected to the pole column to achieve the transmission of electrical energy. In related technologies, the connecting piece is usually located between the electrode group and the pole column. However, the connecting piece is easy to deform and damage the diaphragm in the electrode group, which in turn causes an internal short circuit in the battery cell and affects the safety of the battery. Utility Model Content
[0003] The utility model aims to overcome the defect in the related art that the connecting piece is easy to deform and damage the diaphragm, causing internal short circuit of the battery cell and affecting the safety of the battery, thereby providing a battery cell and a battery pack.
[0004] In the first aspect, the utility model provides a battery cell, comprising: a shell having a first opening and a second opening relative to each other; a pole group disposed in the shell; a first cover plate assembly, comprising a first cover body and a first pole and a connecting piece disposed on the first cover body; the first cover body is connected to the shell and blocks the first opening; the connecting piece is located on a side of the first cover body close to the pole group, the connecting piece is electrically connected to the first pole, and is electrically connected to the pole group; an insulating member is disposed between the connecting piece and the pole group, and the insulating member is provided with a first through hole, and the pole group is electrically connected to the connecting piece through the first through hole; a second cover plate assembly is connected to the shell and blocks the second opening; the second cover plate assembly includes a second pole, and the second pole is electrically connected to the pole group.
[0005] Optionally, the pole group has a first end face, and the first end face is provided with a first pole ear; the insulating member is arranged on the first end face, and the first through hole is arranged corresponding to the first pole ear; the first pole ear is passed through the first through hole, and at least part of the structure extends out of the first through hole and is bent to form an accommodation space; the connecting piece is arranged in the accommodation space and is electrically connected to the first pole ear.
[0006] Optionally, a minimum distance d1 between the first through hole and the first electrode tab is ≥1 mm.
[0007] Optionally, the pole group has a first end face and a second end face arranged opposite to each other; in the direction from the first end face to the second end face, the projection of the insulating member is located within the first end face; wherein the distance d2 between the edge of the insulating member and the edge of the first end face satisfies: d2<d1.
[0008] Optionally, the connecting piece includes a first connecting portion and a second connecting portion which are connected to each other, the first connecting portion is electrically connected to the first pole, the second connecting portion is electrically connected to the first pole tab, and the connecting portion of the second connecting portion and the first pole tab is located in the accommodating space.
[0009] Optionally, the minimum distance between the first through hole and the first electrode tab is d1; the distance between the end of the second connecting portion away from the first connecting portion and the first through hole is d3; wherein d3>d1.
[0010] Optionally, a minimum distance d4 between the first through hole and the edge of the insulating member is ≥1.5 mm.
[0011] Optionally, the first cover body is provided with a second through hole, and the second through hole is arranged corresponding to at least a portion of the bent structure of the first electrode tab, so as to weld the first electrode tab to the second connecting portion.
[0012] Optionally, the second cover plate assembly further includes a second cover body, an explosion-proof valve and a liquid injection hole, the second cover body is connected to the shell and blocks the second opening; the second pole, the explosion-proof valve and the liquid injection hole are all arranged on the second cover body.
[0013] In a second aspect, the utility model further provides a battery pack, comprising: at least one battery cell as described above.
[0014] By utilizing the technical solution of the utility model, an insulating member is provided between the electrode group and the connecting sheet of the first cover plate assembly, and the first through hole of the insulating member can realize the connection between the electrode group and the connecting sheet, and then realize the electrical connection between the electrode group and the first pole through the connecting sheet; and the insulating member is arranged between the connecting sheet and the electrode group, which can prevent the connecting sheet from deforming and damaging the diaphragm, reduce or even eliminate the occurrence of internal short circuit of the battery cell, and improve the safety of the battery. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 This is a schematic structural diagram of a battery cell according to an embodiment of the utility model from a first viewing angle;
[0017] Figure 2 This is a schematic structural diagram of a battery cell according to an embodiment of the utility model from a second viewing angle;
[0018] Figure 3 A cross-sectional view of a battery cell according to an embodiment of the utility model;
[0019] Figure 4 A cross-sectional view of a first cover plate assembly according to an embodiment of the utility model;
[0020] Figure 5 This is a structural schematic diagram of a first cover plate assembly in a first viewing angle according to an embodiment of the utility model;
[0021] Figure 6 This is a schematic structural diagram of a first cover plate assembly in a second viewing angle according to an embodiment of the utility model;
[0022] Figure 7 This is a schematic structural diagram of an insulating member according to an embodiment of the utility model;
[0023] Figure 8 This is a schematic diagram of the assembly process of a pole group, an insulating member and a connecting piece according to an embodiment of the utility model; wherein: Figure 8 (a) is a schematic diagram of the assembly of the pole group and the insulating parts; Figure 8 (b) is a schematic diagram of the assembly of the pole group, insulating parts and connecting pieces; Figure 8 (c) is a schematic diagram of the assembly of the first pole ear and the connecting piece of the pole group;
[0024] Fig. 9 for Figure 8 (a) is a side cross-sectional view;
[0025] Fig.10 for Figure 8 A local enlarged schematic diagram of point A in (b);
[0026] Fig.11 for Figure 8 (c) is a side cross-sectional view;
[0027] Fig.12 It is a schematic diagram of the assembly of the pole group, the insulating member and the first cover plate assembly;
[0028] Fig.13 It is a schematic diagram of the assembly of the first electrode tab and the first cover plate assembly.
[0029] Description of reference numerals:
[0030] 1. housing; 11. first opening; 12. second opening;
[0031] 2. pole group; 21. first pole ear; 211. bending portion; 212. accommodation space; 22. second pole ear; 23. first end face; 24. second end face;
[0032] 3. Insulating member; 31. First through hole;
[0033] 4. First cover plate assembly; 41. First cover body; 411. Second through hole; 412. Welding area; 42. First pole; 43. Connecting piece; 431. First connecting part; 432. Second connecting part; 44. Sealing plate;
[0034] 5. Second cover plate assembly; 51. Second cover body; 52. Second pole; 53. Explosion-proof valve; 54. Liquid injection hole. DETAILED DESCRIPTION
[0035] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of 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.
[0036] Combine the following Figures 1 to 13 , describing an embodiment of the utility model.
[0037] According to an embodiment of the present invention, a battery pack is provided, comprising at least one battery cell. It is understandable that the battery pack may include one, two or more battery cells, and the present invention does not specifically limit the number of battery cells, as long as the design requirements are met.
[0038] Specifically, Figure 1 and 2 As shown, the battery cell includes a shell 1, an electrode group 2, and a first cover plate assembly 4 and a second cover plate assembly 5 arranged at opposite ends of the shell 1. The shell 1 is hollow inside and has a first opening 11 and a second opening 12 opposite to each other, and the electrode group 2 is arranged inside the shell 1. The first cover plate assembly 4 is connected to the shell 1 and blocks the first opening 11, and the first pole 42 of the first cover plate assembly 4 is electrically connected to the first end of the electrode group 2. The second cover plate assembly 5 is connected to the shell 1 and blocks the second opening 12, and the second pole 52 of the second cover plate assembly 5 is electrically connected to the second end of the electrode group 2.
[0039] It can be understood that the first end of the pole group 2 is disposed corresponding to the first opening 11 of the shell 1 , and the second end of the pole group 2 is disposed corresponding to the second opening 12 of the shell 1 .
[0040] In some embodiments, the first pole 42 may be a positive terminal of the battery cell, and the second pole 52 may be a negative terminal of the battery cell. Alternatively, in some embodiments, the first pole 42 may be a negative terminal of the battery cell, and the second pole 52 may be a positive terminal of the battery cell.
[0041] Furthermore, in some embodiments, Figure 3As shown, the first cover plate assembly 4 includes a first cover body 41 and the above-mentioned first pole 42 and a connecting piece 43 arranged on the first cover body 41. Among them, the first cover body 41 is connected to the shell 1 and blocks the first opening 11. Exemplarily, the side of the first cover body 41 facing the shell 1 is welded to the shell 1, specifically, the inner side of the first cover body 41 is welded to the shell wall at the first opening 11 of the shell 1. The connecting piece 43 is located on the side of the first cover body 41 close to the shell 1, that is, the side close to the pole group 2, more specifically, the connecting piece 43 is connected to the inner side of the first cover body 41. The connecting piece 43 is electrically connected to the first pole 42 and the pole group 2. The first pole 42 extends from the inner side to the outer side of the first cover body 41, and the partial structure of the first pole 42 located on the inner side of the first cover body 41 is electrically connected to the connecting piece 43, and at least a part of the structure of the first pole 42 is exposed on the outer side of the first cover body 41 to facilitate electrical transmission with external components.
[0042] It can be understood that the inner side of the first cover body 41 refers to the side of the first cover body 41 close to the shell 1 when assembled on the shell 1, and the outer side of the first cover body 41 refers to the side of the first cover body 41 away from the shell 1 when assembled on the shell 1.
[0043] Furthermore, in this embodiment, an insulating member 3 is provided between the connecting piece 43 and the electrode group 2 , and the insulating member 3 is provided with a first through hole 31 , and the electrode group 2 is electrically connected to the connecting piece 43 through the first through hole 31 .
[0044] By utilizing the technical solution of the utility model, an insulating member 3 is provided between the pole group 2 and the connecting piece 43 of the first cover plate assembly 4, and the first through hole 31 of the insulating member 3 can realize the connection between the pole group 2 and the connecting piece 43, and then realize the electrical connection between the pole group 2 and the first pole 42 through the connecting piece 43; and, the insulating member 3 is arranged between the connecting piece 43 and the pole group 2, which can prevent the connecting piece 43 from deforming and damaging the diaphragm, reduce or even eliminate the occurrence of internal short circuit of the battery cell, and improve the safety of the battery.
[0045] Specifically, in some embodiments, the pole group 2 is relatively provided with a first end face 23 and a second end face 24, the first end face 23 is formed at the first end of the pole group 2, and the second end face 24 is formed at the second end of the pole group 2. The first end face 23 of the pole group 2 is provided with a first pole ear 21, and the first pole ear 21 is electrically connected to the first pole column 42; the second end face 24 of the pole group 2 is provided with a second pole ear 22, and the second pole ear 22 is electrically connected to the second pole column 52.
[0046] It can be understood that the first pole lug 21, the second pole lug 22 and the connecting piece 43 are all made of metal materials, and electrical connection can be achieved through stable mechanical connection. Exemplarily, the first pole lug 21 is welded to the connecting piece 43, and the connecting piece 43 is welded to the first pole 42, thereby achieving electrical connection between the first pole lug 21 and the first pole 42. Exemplarily, the second pole lug 22 is welded to the second pole 52, thereby achieving electrical connection between the second pole lug 22 and the second pole 52.
[0047] Further, in some embodiments, the insulating member 3 is disposed on the first end surface 23, and the first through hole 31 of the insulating member 3 is disposed corresponding to the first pole tab 21. The first pole tab 21 is inserted into the first through hole 31, and at least a portion of the structure extends out of the first through hole 31 and is bent to form an accommodation space 212. The connecting piece 43 is disposed in the accommodation space 212 and is electrically connected to the first pole tab 21.
[0048] For example, Fig.11 As shown, in this embodiment, at least part of the structure of the first pole tab 21 extends out of the first through hole 31 and is bent to form a bent portion 211. An accommodation space 212 is formed between the bent portion 211 and the insulating member 3, and the connecting piece 43 is placed in the accommodation space 212 and welded to the first pole tab 21.
[0049] In the present embodiment, the electrical connection between the first pole ear 21 and the connecting piece 43 can be achieved by bending the first pole ear 21. The connecting piece 43 does not need to be bent, thereby reducing the bending process of the connecting piece 43 and improving the production efficiency of the battery cell; and the connecting piece 43 is located in the accommodating space 212 formed after the first pole ear 21 is bent, which saves the space required for the connection between the two to the maximum extent and improves the space utilization inside the battery cell.
[0050] Furthermore, in some embodiments, the first pole tab 21 is inserted into the first through hole 31, and a gap is provided between the first through hole 31 and the outer peripheral side of the first pole tab 21. Fig. 9 As shown, the minimum distance between the first through hole 31 and the first pole tab 21 is defined as d1, and the value of d1 is greater than or equal to 1 mm, so that the first pole tab 21 can be easily installed in the connecting piece 43 during assembly and avoid interference with the insulating member 3 and tearing of the first pole tab 21.
[0051] Furthermore, in the direction from the first end face 23 to the second end face 24, the projection of the insulating member 3 is located inside the first end face 23, and the projection of the connecting piece 43 is located inside the insulating member 3. That is, in the direction from the first end face 23 to the second end face 24, the cross-sectional area of the insulating member 3 is smaller than the cross-sectional area of the first end face 23, and the cross-sectional area of the connecting piece 43 is smaller than the cross-sectional area of the insulating member 3. With such a configuration, the insulating member 3 can be fully isolated between the connecting piece 43 and the electrode group 2, further improving the safety of the battery cell. Figure 1 and Figure 2 The Z direction is shown.
[0052] Among them, Fig. 9 As shown, there is a distance between the edge of the insulating member 3 and the edge of the first end face 23 , and the distance is defined as d2 . The value of d2 is smaller than the value of d1 to avoid interference between the insulating member 3 and the first pole ear 21 due to assembly error.
[0053] For ease of description, Figure 1 and 2 As shown, the height direction of the battery cell is defined as the Z direction, the length direction of the battery cell is defined as the X direction, and the width direction of the battery cell is defined as the Y direction. After assembly, the first cover plate assembly 4 and the second cover plate assembly 5 are respectively located at both ends of the Z direction of the shell 1. The thickness direction of the insulating member 3 corresponds to the Z direction of the battery cell, the length direction of the insulating member 3 corresponds to the X direction of the battery cell, and the width direction of the insulating member 3 corresponds to the Y direction of the battery cell. The first pole ear 21 extends along the Z direction, and the length direction of the first pole ear 21 corresponds to the X direction, and the thickness direction of the first pole ear 21 corresponds to the Y direction.
[0054] For example, Figure 7 As shown, the insulating member 3 is configured as a sheet structure, the first through hole 31 is configured as a long hole, and the first through hole 31 extends along the length direction of the insulating member 3 .
[0055] The length of the first through hole 31 is greater than the length of the first pole tab 21. In some embodiments, the difference between the length of the first through hole 31 and the length of the first pole tab 21 is greater than 1 mm, preferably greater than 2 mm. Exemplarily, the difference is 3 mm. In some embodiments, the length of the first through hole 31 ranges from 10 to 100 mm.
[0056] The dimension of the first through hole 31 in the width direction is greater than the dimension of the first pole tab 21 in the thickness direction, and the difference between the dimension of the first through hole 31 in the width direction and the dimension of the first pole tab 21 in the thickness direction is greater than 1 mm, preferably greater than 2 mm. In some embodiments, the width of the first through hole 31 ranges from 10 to 35 mm, and the thickness of the first pole tab 21 ranges from 0.08 to 1.1 mm.
[0057] The utility model does not specifically limit the length and width of the insulating member 3, and the length and width of the insulating member 3 depend on the size of the first end face 23 of the pole group 2. Specifically, the length of the insulating member 3 can be equal to the size of the first end face 23 in the X direction, or the length of the insulating member 3 is smaller than the size of the first end face 23 in the X direction; the width of the insulating member 3 can be equal to the size of the first end face 23 in the Y direction, or the width of the insulating member 3 is smaller than the size of the first end face 23 in the Y direction.
[0058] In some embodiments, the thickness of the insulating member 3 is in the range of 0.2-1.2 mm.
[0059] Furthermore, if Figure 3 As shown, in some embodiments, the connecting piece 43 includes a first connecting portion 431 and a second connecting portion 432 connected to each other, the first connecting portion 431 is electrically connected to the first pole 42, the second connecting portion 432 is electrically connected to the first pole lug 21, and the connecting portion of the second connecting portion 432 with the first pole lug 21 is located in the accommodation space 212 formed by the bending portion 211 of the first pole lug 21. In this way, the first pole 42 and the first pole lug 21 are respectively connected to the two parts of the connecting piece 43, so that the first pole 42 and the first pole lug 21 can be staggered in the length direction (X direction) of the battery cell, saving the internal space in the height (Z direction) of the battery cell.
[0060] For example, Figure 6 As shown, the first connection portion 431 and the second connection portion 432 are both configured as sheet structures, and in the Y direction, the width of the first connection portion 431 is greater than the width of the second connection portion 432 .
[0061] Among them, Figure 8 and 10 As shown, the distance between the end of the second connection portion 432 away from the first connection portion 431 and the first through hole 31 is defined as d3, and the value of d3 is greater than the value of d1 to prevent the connection sheet 43 from contacting the diaphragm in the electrode group 2.
[0062] It can be understood that the first through hole 31 is arranged through the insulating member 3 in the thickness direction, and the arrangement position of the first through hole 31 on the insulating member 3 depends on the arrangement position of the first electrode tab 21. Fig. 9As shown, the minimum distance between the first through hole 31 and the edge of the insulating member 3 is defined as d4. In some embodiments, the value of d4 is greater than or equal to 1.5 mm, which can not only ensure the structural strength of the insulating member 3, but also ensure that the diaphragm of the electrode group 2 is not punctured by the connecting piece 43, thereby improving the safety of the battery.
[0063] Furthermore, in some embodiments, Figure 4-6 As shown, the first cover 41 is provided with a second through hole 411, which penetrates the inner side and the outer side of the first cover 41, and the second through hole 411 is arranged corresponding to at least a part of the bent structure of the first pole tab 21, that is, the second through hole 411 is arranged corresponding to the bent portion 211 of the first pole tab 21. Fig.13 As shown, a welding channel between the bent portion 211 of the first pole tab 21 and the second connecting portion 432 is formed at the second through hole 411, so as to facilitate welding the first pole tab 21 and the second connecting portion 432 to form a welding area 412. It can be understood that after assembly, the direction from the inside to the outside of the first cover body 41 corresponds to the above-mentioned Z direction.
[0064] Specifically, Figure 6 As shown, the second connection portion 432 of the connection sheet 43 is arranged corresponding to the second through hole 411 , and at least part of the second connection portion 432 and the second through hole 411 are staggered so that the first electrode tab 21 can extend out of the first cover 41 through the second through hole 411 .
[0065] Accordingly, if Figure 4 As shown, the first cover plate assembly 4 further includes a sealing plate 44, which is disposed at the second through hole 411, and the sealing plate 44 is connected to the first cover body 41 and blocks the second through hole 411. Exemplarily, the sealing plate 44 is welded to the first cover body 41.
[0066] Furthermore, if Figure 2 and 3 As shown, in some embodiments, the second cover plate assembly 5 further includes a second cover body 51 and a second pole 52, an explosion-proof valve 53 and an injection hole 54 arranged on the second cover body 51. The second cover body 51 is connected to the shell 1 and blocks the second opening 12. For example, the side of the second cover body 51 facing the shell 1 is welded to the shell 1, specifically, the inner side of the second shell 1 is welded to the shell wall at the second opening 12 of the shell 1. The second pole 52 extends from the inner side to the outer side of the second cover body 51, and the part of the second pole 52 located on the inner side of the second cover body 51 is electrically connected to the second pole ear 22, and at least part of the second pole 52 is exposed on the outer side of the second cover body 51 to facilitate electrical transmission with external elements. The explosion-proof valve 53 can be a weak area arranged on the second cover body 51. The injection hole 54 is connected to the inside of the pole group 2 and the outer side of the second cover body 51, and the injection hole 54 is used to inject electrolyte into the pole group 2.
[0067] It can be understood that the inner side of the second cover body 51 refers to the side of the second cover body 51 close to the shell 1 when assembled on the shell 1, and the outer side of the second cover body 51 refers to the side of the second cover body 51 away from the shell 1 when assembled on the shell 1.
[0068] The assembly process of the pole group 2, the insulating member 3 and the connecting piece 43 of the utility model is as follows Figure 8 As shown, Figure 8 (a) is a schematic diagram of the assembly of the pole group 2 and the insulating member 3; Figure 8 (b) is a schematic diagram of the assembly of the pole group 2, the insulating member 3 and the connecting piece 43; Figure 8 (c) is a schematic diagram of the assembly of the first electrode tab 21 of the electrode group 2 and the connecting piece 43 .
[0069] The assembly process of the utility model is:
[0070] like Figure 8 As shown in (a), the insulating member 3 is installed on the first end surface 23 of the pole group 2, and the first pole tab 21 passes through the first through hole 31; in this step, the first pole tab 21 can be roughly located in the middle of the first through hole 31 by a positioning tool;
[0071] like Figure 8 As shown in (b), the connecting piece 43 is placed on the insulating member 3, and the second connecting portion 432 of the connecting piece 43 is located on one side of the first electrode tab 21;
[0072] like Figure 8 As shown in (c), the first electrode tab 21 is bent toward the second connection portion 432 and connected to the second connection portion 432, that is, welded, to form a welding area 412.
[0073] It can be understood that in some embodiments, the first cover plate assembly 4 is supplied as an assembly, that is, the connecting piece 43 is connected to the first cover body 41 as an integral structure before assembly. The assembly process is as follows: Fig.12 and 13 As shown:
[0074] like Figure 8 As shown in (a), the insulating member 3 is installed on the first end surface 23 of the pole group 2, and the first pole ear 21 passes through the first through hole 31;
[0075] like Fig.12 As shown, the first cover plate assembly 4 is installed on the housing 1, wherein the first pole ear 21 passes through the second through hole 411 of the first cover body 41, and the second connecting portion 432 of the connecting sheet 43 is located at one side of the first pole ear 21;
[0076] like Fig.13As shown, the first electrode tab 21 is bent toward the second connection portion 432 and connected to the second connection portion 432 , ie, welded, to form a welding area 412 .
[0077] Although the embodiments of the present invention 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 invention, and such modifications and variations are all within the scope defined by the appended claims.
Claims
1. A battery cell, characterized in that: include: A housing having a first opening and a second opening opposite to each other; A pole group, arranged in the shell; A first cover plate assembly, comprising a first cover body and a first pole and a connecting piece provided on the first cover body; the first cover body is connected to the housing and blocks the first opening; the connecting piece is located on a side of the first cover body close to the pole group, the connecting piece is electrically connected to the first pole and the pole group; An insulating member is disposed between the connecting sheet and the electrode group, and the insulating member is provided with a first through hole, and the electrode group is electrically connected to the connecting sheet through the first through hole; The second cover plate assembly is connected to the shell and blocks the second opening; the second cover plate assembly includes a second pole, and the second pole is electrically connected to the pole group.
2. The battery cell according to claim 1, characterized in that: The pole group has a first end surface, and the first end surface is provided with a first pole lug; The insulating member is arranged on the first end surface, and the first through hole is arranged corresponding to the first electrode tab; The first electrode tab is inserted into the first through hole, and at least a portion of the structure extends out of the first through hole and is bent to form an accommodation space; The connecting sheet is disposed in the accommodating space and is electrically connected to the first electrode tab.
3. The battery cell according to claim 2, characterized in that: A minimum distance d1 between the first through hole and the first electrode tab is ≥1 mm.
4. The battery cell according to claim 3, characterized in that: The pole group has a first end face and a second end face that are arranged opposite to each other; in the direction from the first end face to the second end face, the projection of the insulating member is located within the first end face; Wherein, a distance d2 between the edge of the insulating member and the edge of the first end surface satisfies: d2<d1.
5. The battery cell according to claim 2, characterized in that: The connecting piece includes a first connecting portion and a second connecting portion which are connected to each other. The first connecting portion is electrically connected to the first pole, the second connecting portion is electrically connected to the first pole tab, and a connecting portion of the second connecting portion and the first pole tab is located in the accommodating space.
6. The battery cell according to claim 5, characterized in that: The minimum distance between the first through hole and the first electrode tab is d1; the distance between the end of the second connecting portion away from the first connecting portion and the first through hole is d3; wherein d3>d1.
7. The battery cell according to claim 1, characterized in that: A minimum distance d4 between the first through hole and the edge of the insulating member is ≥1.5 mm.
8. The battery cell according to claim 5, characterized in that: The first cover body is provided with a second through hole, and the second through hole is arranged corresponding to the at least partial structure of the bent first electrode tab, so as to weld the first electrode tab to the second connecting portion.
9. The battery cell according to any one of claims 1 to 8, characterized in that: The second cover plate assembly also includes a second cover body, an explosion-proof valve and a liquid injection hole. The second cover body is connected to the shell and blocks the second opening. The second pole, the explosion-proof valve and the liquid injection hole are all arranged on the second cover body.
10. A battery pack, characterized in that: include: At least one battery cell according to any one of claims 1 to 9.