Batteries and battery packs

Abstract

The present invention relates to the field of battery technology, and discloses a battery and a battery pack, wherein the battery comprises a shell, a pole group and a negative pole cover. The shell comprises a bottom wall arranged at one end, and the bottom wall comprises a bottom wall body and an elastic rib surface which is recessed inwardly from the bottom wall body; the pole group is arranged in the shell, and the pole group is electrically connected to at least part of the elastic rib surface, and the elastic rib surface is suitable for elastic deformation along the height direction of the pole group; the negative pole cover is arranged on the elastic rib surface, and the negative pole cover is connected to the shell. In the battery provided by the present invention, when the manufacturing error of the pole group in height is large, the elastic rib surface can compensate for the height of the pole group, make up for the defect of insufficient height accuracy of the pole group, increase the flexibility of product processing and manufacturing, and improve the yield rate and product performance. The pole group and at least part of the elastic rib surface are electrically connected, thereby eliminating the negative pole connecting piece, reducing the number of parts, greatly saving product costs, simplifying the assembly process, and improving production efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to batteries and battery packs. Background Art

[0002] As lithium-ion battery technology becomes increasingly mature, power batteries are widely used in electric vehicles as a new type of battery, and the performance and safety requirements of power batteries are increasing.

[0003] The electrode structure of cylindrical batteries currently on the market includes upper plastic, lower plastic, pole, sealing ring, positive electrode connecting piece, negative electrode connecting piece, negative electrode cover, sealing cover and sealing nails. The existing electrode structure has the following disadvantages: more parts, higher cost, complex assembly process, especially more welding processes, which can easily lead to poor performance and quality problems; due to the low manufacturing accuracy in the height direction of the pole group, the battery yield is low. Summary of the invention

[0004] In view of this, the present invention provides a battery and a battery pack to solve at least one of the following technical problems: the battery has many parts and components, the cost is high, the assembly process is complicated, the production efficiency is low, and the yield rate is low.

[0005] In a first aspect, the present invention provides a battery, comprising a housing, an electrode group and a negative electrode cover. The housing comprises a bottom wall arranged at one end, the bottom wall comprising a bottom wall body and an elastic rib surface recessed inwardly from the bottom wall body; the electrode group is arranged in the housing, the electrode group is electrically connected to at least part of the elastic rib surface, and the elastic rib surface is suitable for elastic deformation along the height direction of the electrode group; the negative electrode cover is arranged on the elastic rib surface, and the negative electrode cover is connected to the housing.

[0006] With the battery provided by the present invention, since the elastic rib surface is arranged on the bottom wall of the shell, it can support the electrode group. When the manufacturing error of the electrode group in height is large, the elastic rib surface can compensate for the height of the electrode group, make up for the defect of insufficient height precision of the electrode group, increase the flexibility of product processing and manufacturing, and improve the yield rate and product performance. The elastic rib surface is arranged in a concave shape, and the electrode group and at least part of the elastic rib surface are electrically connected, thereby eliminating the negative electrode connecting sheet, reducing the number of parts, greatly saving product costs, simplifying the assembly process, and improving production efficiency, so that it has sufficient market competitiveness.

[0007] In an optional embodiment, the elastic rib surface includes at least two welding areas and at least two isolation areas, the welding areas and the isolation areas are alternately arranged around the center of the pole group, and the welding areas and the pole group are penetrated and welded.

[0008] This arrangement ensures that the elastic rib surface has sufficient elasticity, thereby improving the performance of the elastic rib surface in compensating for the manufacturing accuracy of the electrode group height and ensuring stable performance of the battery cell.

[0009] In an optional embodiment, the ratio of the area of ​​the welding region to the area of ​​the bottom surface of the electrode group is not less than 2 / 5.

[0010] When the ratio of the area of ​​the welding area to the area of ​​the bottom surface of the electrode group is controlled within a range of not less than 2 / 5, the current capacity can be guaranteed. When it exceeds this range, the welding area is small, the welding performance is reduced, and the stability of the battery performance is affected. Preferably, the ratio of the area of ​​the welding area to the area of ​​the bottom surface of the electrode group is 1 / 2.

[0011] In an optional implementation, the isolation area is a through hole penetrating the elastic rib surface.

[0012] The through hole is provided, the structure is simple, and the processing and manufacturing are convenient, which is beneficial to improving the battery production efficiency.

[0013] In an optional embodiment, the shell is cylindrical, the elastic rib surface is annular, the welding area is a sector with the center of the elastic rib surface as the center, and the welding areas are evenly spaced around the center of the elastic rib surface.

[0014] This arrangement allows the pole group and the elastic rib surface to be welded together radially from the inside to the outside, thereby increasing the welding area and improving the welding performance and effect.

[0015] In an optional embodiment, the deformation range of the elastic rib surface along the height direction of the pole group is -0.3 mm to 0.3 mm.

[0016] Controlling the deformation stroke of the elastic rib surface within the range of -0.3mm to 0.3mm can compensate for the manufacturing accuracy error of the electrode group in the height direction and ensure the stable performance of the battery cell. When it exceeds this range, the structural strength of the elastic rib surface will be affected.

[0017] In an optional embodiment, the elastic rib surface and the bottom wall of the shell are integrally formed.

[0018] With this arrangement, the elastic rib surface and the shell are made of the same material, and the one-piece molding facilitates processing and manufacturing, which is beneficial to simplifying the battery assembly process and improving battery production efficiency.

[0019] In an optional embodiment, it also includes a positive cover plate, which includes a positive cover plate body and a recessed portion arranged in the middle of the positive cover plate body and facing the electrode group. The periphery of the positive cover plate body and the periphery of the other end of the shell are welded, and the recessed portion is provided with a mounting hole. The mounting hole is connected to a pole via an insulating seal, and the pole post is electrically connected to the positive pole of the electrode group.

[0020] Compared with the existing seals and insulating parts which are independent components, the battery in the embodiment of the present invention integrates the seals and insulating parts into one structural part, which not only improves the sealing and insulation performance, but also reduces the number of parts, simplifies the assembly process, greatly saves battery costs, and improves the competitiveness of the product.

[0021] In an optional embodiment, the positive electrode cover plate also includes a protrusion arranged toward the electrode group away from the electrode group, the protrusion is arranged around the recessed portion, the inner circle of the protrusion is connected to the recessed portion, and the outer circle of the protrusion is connected to the positive electrode cover plate body; the protrusion is provided with an explosion-proof valve; and the negative electrode cover plate is provided with a liquid injection hole.

[0022] The explosion-proof valve is arranged on the raised part, and the injection hole is arranged on the negative electrode cover plate. The explosion-proof valve and the injection hole are separately arranged on different end faces. When the explosion-proof valve leaks due to breakdown, the injection hole is prevented from being contaminated, thereby improving the assembly yield of the product and saving product costs.

[0023] In a second aspect, the present invention further provides a battery pack, comprising a battery according to any one of the above technical solutions.

[0024] Since the battery pack includes the above-mentioned battery, it has the same effect as the battery and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention 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 present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A three-dimensional diagram of a battery housing and a negative electrode cover plate after being assembled according to an embodiment of the present invention;

[0027] Figure 2 for Figure 1 A top view of the battery shown;

[0028] Figure 3 for Figure 1 Sectional view along AA;

[0029] Figure 4 for Figure 3 A partial enlarged schematic diagram of point B in the middle;

[0030] Figure 5 is a schematic diagram of the structure of the shell;

[0031] Figure 6 for Figure 5 A top view of

[0032] Figure 7 A schematic structural diagram of a positive electrode cover plate of a battery according to an embodiment of the present invention;

[0033] Figure 8 for Figure 7 A top view of

[0034] Fig. 9 for Figure 8 Cross-sectional view at the middle edge CC;

[0035] Fig.10 for Fig. 9 A partial enlarged schematic diagram of point D in the middle;

[0036] Fig.11 is a three-dimensional diagram of a battery according to an embodiment of the present invention;

[0037] Fig.12 for Fig.11 A cross-sectional view of

[0038] Fig.13 for Fig.12 A partial enlarged schematic diagram of the positive terminal;

[0039] Fig.14 for Fig.12 A partial enlarged schematic diagram of the middle negative terminal.

[0040] Description of reference numerals:

[0041] 1. Shell; 101. Bottom wall; 102. Elastic rib surface; 1021. Welding area; 1022. Isolation area; 2. Pole group; 3. Negative electrode cover; 301. Negative electrode cover body; 302. Raised ridge; 4. Positive electrode cover; 401. Positive electrode cover body; 402. Recessed portion; 403. Raised portion; 5. Explosion-proof valve; 6. Liquid injection hole; 7. Pole; 701. Pole body; 702. First convex edge; 703. Second convex edge; 8. Insulating seal; 801. First sealing section; 802. Second sealing section; 803. Third sealing section; 9. Positive electrode connecting piece. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0043] In the related art, the electrode structure of the cylindrical battery includes upper plastic, lower plastic, pole, sealing ring, positive electrode connecting piece, negative electrode connecting piece, negative electrode cover, sealing cover and sealing nails and other components, among which the positive and negative electrode connecting pieces and pole groups, the positive electrode connecting piece and pole, the negative electrode connecting piece and shell, and the negative electrode cover and shell are all connected by welding; after the pole is assembled into the shell, the upper and lower plastics and the sealing ring are compacted by riveting to achieve a sealing and insulating effect; after the pole group is put into the shell, the negative pole and the negative electrode connecting piece are laser welded, the negative electrode connecting piece is laser welded to the shell, and then the negative electrode cover and the shell are laser welded. After the injection is completed, the sealing cover and the negative electrode cover are laser welded.

[0044] Combine the following Figures 1 to 14 , describing an embodiment of the present invention.

[0045] According to an embodiment of the present invention, on the one hand, a battery is provided, comprising a housing 1, an electrode group 2 and a negative electrode cover plate 3. The housing 1 comprises a bottom wall 101 arranged at one end, the bottom wall 101 comprises a bottom wall 101 body and an elastic rib surface 102 which is recessed inwardly from the bottom wall 101 body; the electrode group 2 is arranged in the housing 1, the electrode group 2 is electrically connected to at least part of the elastic rib surface 102, and the elastic rib surface 102 is suitable for elastic deformation along the height direction of the electrode group 2; the negative electrode cover plate 3 is arranged on the elastic rib surface 102, and the negative electrode cover plate 3 is connected to the housing 1.

[0046] With the battery provided by the present invention, since the elastic rib surface 102 is provided on the bottom wall 101 of the shell 1, it can support the electrode group 2. When the manufacturing error of the electrode group 2 in height is large, the elastic rib surface 102 can compensate for the height of the electrode group 2, make up for the defect of insufficient height precision of the electrode group 2, increase the flexibility of product processing and manufacturing, and improve the yield rate and product performance. The elastic rib surface 102 is concavely arranged to electrically connect the electrode group 2 and at least part of the elastic rib surface 102, thereby eliminating the negative electrode connecting sheet, reducing the number of parts, greatly saving product costs, simplifying the assembly process, and improving production efficiency, making it sufficiently competitive in the market.

[0047] Since the manufacturing error of the electrode group 2 in height is ±0.3mm, the elastic rib surface 102 is provided so that the electrode group 2 has the ability of elastic deformation in the height direction, and can compensate for the manufacturing error of the electrode group 2 in the height direction. For example, when the error of the electrode group 2 in the height direction is -0.3mm, the elastic rib surface 102 is close to the deformation stroke of the electrode group 2 of 0.3mm, so that the elastic rib surface 102 and the electrode group 2 are tightly welded. Otherwise, there is a gap between the elastic rib surface 102 and the electrode group 2, which is prone to large welding spots or weak welding, resulting in a weak connection between the negative electrode cover plate 3 and the electrode group 2, and a poor contact phenomenon; when the error of the electrode group 2 in the height direction is 0.3mm, the elastic rib surface 102 is away from the deformation stroke of the electrode group 2 of 0.3mm, so as to ensure the welding performance between the electrode group 2 and the negative electrode cover plate 3.

[0048] In addition, since the negative terminal of the battery has only two layers of structure, namely the bottom wall of the shell and the negative electrode cover plate, compared with the negative electrode cover plate with a multi-layer structure in the related art, the number of parts is reduced and the assembly process is simplified.

[0049] Specifically, the structure of the housing 1 can be cylindrical, suitable for cylindrical batteries, or can be a cubic structure, suitable for square batteries. Figure 1 The housing 1 comprises a cylindrical housing body 1 having a cavity for accommodating the pole group 2. The bottom wall 101 of the housing 1 is arranged at one end of the housing body 1.

[0050] In an optional embodiment, referring to Figure 5 and Figure 6 The elastic rib surface 102 includes at least two welding areas 1021 and at least two isolation areas 1022. The welding areas 1021 and the isolation areas 1022 are alternately arranged around the center of the electrode group 2. The welding areas 1021 and the electrode group 2 are penetrated and welded. Specifically, in this embodiment, three welding areas 1021 are provided, and three isolation areas 1022 are provided. The three welding areas 1021 and the three isolation areas 1022 are alternately arranged around the center of the electrode group 2.

[0051] Such an arrangement enables the elastic rib surface 102 to have sufficient elasticity, thereby improving the performance of the elastic rib surface 102 in compensating for the manufacturing accuracy of the electrode group 2 height, and ensuring stable performance of the battery cell.

[0052] In an optional implementation, the ratio of the area of ​​the welding region 1021 to the area of ​​the bottom surface of the electrode group 2 is not less than 2 / 5.

[0053] Specifically, the structure of the electrode group 2 is adapted to the structure of the housing 1. In this embodiment, the electrode group 2 is a cylindrical structure. The two ends of the electrode group 2 are respectively a positive terminal and a negative terminal, and the end surfaces of the two ends of the electrode group 2 are the bottom surface of the electrode group 2. The area of ​​the bottom surface of the electrode group 2 is the area of ​​any end surface of the electrode group 2.

[0054] When the ratio of the area of ​​the welding area 1021 to the area of ​​the bottom surface of the electrode group 2 is controlled within a range of not less than 2 / 5, the current capacity can be guaranteed. When it exceeds this range, the welding area is small, the welding performance is reduced, and the stability of the battery performance is affected. Preferably, the ratio of the area of ​​the welding area 1021 to the area of ​​the bottom surface of the electrode group 2 is 1 / 2.

[0055] In an optional implementation, the isolation area 1022 is a through hole penetrating the elastic rib surface 102 .

[0056] The through hole is provided, the structure is simple, and the processing and manufacturing are convenient, which is beneficial to improve the battery production efficiency. Of course, in some other embodiments, the isolation area 1022 can also be a thinned area, that is, the thickness of the isolation area 1022 is less than the thickness of the welding area 1021.

[0057] In an optional embodiment, the shell 1 is cylindrical, the elastic rib surface 102 is annular, the welding area 1021 is a sector with the center of the elastic rib surface 102 as the center, and the welding area 1021 is evenly spaced around the center of the elastic rib surface 102 .

[0058] Such an arrangement enables the electrode group 2 and the elastic rib surface 102 to be welded together from the inside to the outside in the radial direction, thereby increasing the welding area and improving the welding performance and effect.

[0059] In an optional embodiment, the deformation range of the elastic rib surface 102 along the height direction of the pole group 2 is -0.3mm to 0.3mm. Specifically, taking the surface parallel to the bottom surface of the pole group 2 as the reference plane, the deformation stroke of the elastic rib surface 102 toward the side close to the pole group 2 is recorded as negative, and the deformation stroke of the elastic rib surface 102 toward the side away from the pole group 2 is recorded as positive, that is, the deformation range of the elastic rib surface 102 along the height direction of the pole group 2 is -0.3mm to 0.3mm, which can also be said that relative to the reference plane, the deformation range of the elastic rib surface 102 is 0.3mm upward or downward.

[0060] Controlling the deformation stroke of the elastic rib surface 102 within the range of -0.3 mm to 0.3 mm can compensate for the manufacturing precision error of the electrode group 2 in the height direction and ensure the stability of the battery core performance. When the deformation stroke exceeds this range, the structural strength of the elastic rib surface 102 will be affected.

[0061] In an optional embodiment, the elastic rib surface 102 and the bottom wall 101 of the shell 1 are integrally formed.

[0062] With this arrangement, the elastic rib surface 102 and the shell 1 are made of the same material and are integrally formed for easy processing and manufacturing, thereby simplifying the battery assembly process and improving battery production efficiency.

[0063] In an optional embodiment, referring to Figures 1 to 4 The negative electrode cover plate 3 includes a negative electrode cover plate body 301 and a plurality of ridges 302 disposed on the negative electrode cover plate body 301. Specifically, in this embodiment, the negative electrode cover plate body 301 is circular, and the ridges 302 are ring-shaped around the negative electrode cover plate body 301.

[0064] This arrangement can enhance the structural strength of the negative electrode cover 3, making it less likely to deform and improving the stability of battery performance. Figure 4Since the elastic rib surface 102 is provided on the bottom wall 101 of the housing 1, and the elastic rib surface 102 is recessed in the bottom wall 101 of the housing 1, a groove is formed on the bottom wall 101 of the housing 1, and the negative electrode cover 3 is arranged in the groove. The negative electrode cover body 301 abuts against the elastic rib surface 102, and an annular cavity is formed between the ridge 302 and the elastic rib surface 102. In some other embodiments, such as Figure 4 As shown, the upper surface of the ridge 302 is flush with the upper surface of the bottom wall 101 of the housing 1 .

[0065] In an optional embodiment, it also includes a positive electrode cover plate 4, referring to Figures 7 to 10 The positive electrode cover plate 4 includes a positive electrode cover plate body 401 and a recessed portion 402 arranged in the middle of the positive electrode cover plate body 401 and facing the electrode group 2. The periphery of the positive electrode cover plate body 401 and the periphery of the other end of the shell 1 are welded. The recessed portion 402 is provided with a mounting hole, and the mounting hole is connected to the pole 7 through an insulating seal 8. The pole 7 is electrically connected to the positive electrode of the electrode group 2.

[0066] Compared with the existing seals and insulating parts which are independent components, the battery in the embodiment of the present invention integrates the seals and insulating parts into one structural part, which not only improves the sealing and insulation performance, but also reduces the number of parts, simplifies the assembly process, greatly saves battery costs, and improves the competitiveness of the product.

[0067] In an optional embodiment, the positive electrode cover plate 4 also includes a protrusion 403 arranged toward the electrode group 2, the protrusion 403 is arranged around the recessed portion 402, the inner circle of the protrusion 403 is connected to the recessed portion 402, and the outer circle of the protrusion 403 is connected to the positive electrode cover plate body 401; the protrusion 403 is provided with an explosion-proof valve 5, and the negative electrode cover plate 3 is provided with a liquid injection hole 6.

[0068] Specifically, the end faces of the positive electrode cover plate body 401 , the recessed portion 402 and the raised portion 403 are not flush with each other. This arrangement can improve the structural strength of the positive electrode cover plate 4 .

[0069] Specifically, the explosion-proof valve 5 is arranged on the protruding portion 403, and the injection hole 6 is arranged on the negative electrode cover plate 3. The explosion-proof valve 5 and the injection hole 6 are separately arranged on different end faces. When the explosion-proof valve 5 leaks due to breakdown, the injection hole 6 is prevented from being contaminated, thereby improving the assembly yield of the product and saving product costs.

[0070] In an optional embodiment, the edge of the positive electrode cover plate 4 is flush with the edge of the shell 1 , and the periphery of the positive electrode cover plate 4 and the periphery of the shell 1 are welded.

[0071] In an optional embodiment, the pole 7 includes a pole body 701, a first flange 702 provided at the outer end of the pole body 701 and extending in the radial direction, and a second flange 703 provided at the inner end of the pole body 701 and extending in the radial direction, the pole body 701 is sleeved in the mounting hole, the first flange 702 is provided on the outer end surface of the mounting hole, and the second flange 703 is provided on the inner end surface of the mounting hole. The insulating seal 8 includes a plurality of sealing segments, which are alternately arranged in the radial direction and the axial direction, and the plurality of sealing segments are respectively correspondingly provided between the first flange 702 and the outer end surface of the mounting hole, between the pole body 701 and the inner wall of the mounting hole, and between the second flange 703 and the inner end surface of the mounting hole.

[0072] In this arrangement, on the one hand, the multiple sealing segments are alternately arranged in the radial direction and the axial direction to form a circuitous labyrinth sealing structure with better sealing effect. On the other hand, the insulating seal 8 has two functions of insulating and sealing the pole 7 and the positive electrode cover 4, integrating the insulating parts and the sealing parts that exist independently in the related technology into one, which not only reduces the number of parts, but also simplifies the assembly process and improves the production efficiency of the battery.

[0073] In an optional embodiment, the first sealing section 801 and the second sealing section 802 of the insulating seal 8, the first sealing section 801 and the second sealing section 802 both extend in the axial direction, the first sealing section 801 is arranged on the outside of the mounting hole, and the second sealing section 802 is arranged on the inside of the mounting hole, the first sealing section 801 at least partially covers the first flange 702 in the radial direction, and the second sealing section 802 at least partially covers the second flange 703 in the radial direction. Such an arrangement can ensure the insulation between the pole 7 and the positive cover plate 4, and can increase the creepage distance. It should be noted that the above-mentioned "outer end" refers to the end away from the pole group 2, and the "outer side" refers to the side away from the pole group 2; similarly, the above-mentioned "inner end" refers to the end close to the pole group 2, and the "inner side" refers to the side close to the pole group 2.

[0074] In an optional embodiment, referring to Figure 1 Since the positive electrode cover plate 4 is provided with a protrusion 403 and the first sealing section is provided between the protrusion 403 and the first convex edge, the side wall of the protrusion 403 can limit the insulating seal 8 and improve the connection stability of the insulating seal 8.

[0075] In an optional embodiment, referring to Figure 1 The insulating seal 8 includes a third sealing segment 803 extending in the radial direction. The third sealing segment 803 is connected to the first sealing segment 801 , and the third sealing segment 803 is pressed between the first protruding edge 702 and the recessed portion 402 .

[0076] In an optional embodiment, the pole 7 is conductively connected to the positive terminal of the pole group 2 via the positive electrode connecting sheet 9 .

[0077] According to an embodiment of the present invention, on the other hand, a battery pack is provided, comprising a battery according to any one of the above technical solutions.

[0078] Since the battery pack includes the above-mentioned battery, it has the same effect as the battery and will not be described in detail here.

[0079] Although the embodiments of the present invention have been 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, characterized in that: include: A shell, the shell comprising a bottom wall arranged at one end, the bottom wall comprising a bottom wall body and a groove arranged on the bottom wall body, the groove bottom of the groove is an elastic rib surface; the elastic rib surface and the bottom wall of the shell are integrally formed; A pole group is disposed in the housing, the pole group is electrically connected to at least a portion of the elastic rib surface, and the elastic rib surface is suitable for elastic deformation along the height direction of the pole group; A negative electrode cover plate, disposed in the groove and abutting against the elastic rib surface, the negative electrode cover plate being connected to the housing; The elastic rib surface comprises at least two welding areas and at least two isolation areas, the welding areas and the isolation areas are alternately arranged around the center of the pole group, and the welding areas and the pole group are penetrated and welded; The isolation area is a through hole penetrating the elastic rib surface.

2. The battery according to claim 1, characterized in that The ratio of the area of ​​the welding zone to the area of ​​the bottom surface of the electrode group is not less than 2 / 5.

3. The battery according to claim 1 or 2, characterized in that: The shell is cylindrical, the elastic rib surface is annular, the welding area is a sector with the center of the elastic rib surface as the center, and the welding areas are evenly spaced around the center of the elastic rib surface.

4. The battery according to claim 1, characterized in that The deformation range of the elastic rib surface along the height direction of the pole group is -0.3mm to 0.3mm.

5. The battery according to claim 1, characterized in that It also includes a positive electrode cover plate, which includes a positive electrode cover plate body and a recessed portion arranged in the middle of the positive electrode cover plate body and facing the electrode group. The periphery of the positive electrode cover plate body and the periphery of the other end of the shell are welded, and the recessed portion is provided with a mounting hole. The mounting hole is connected to a pole via an insulating seal, and the pole is electrically connected to the positive pole of the electrode group.

6. The battery according to claim 5, characterized in that The positive electrode cover plate also includes a raised portion arranged away from the electrode group, the raised portion is arranged around the recessed portion, the inner circle of the raised portion is connected to the recessed portion, and the outer circle of the raised portion is connected to the positive electrode cover plate body; the raised portion is provided with an explosion-proof valve; and the negative electrode cover plate is provided with a liquid injection hole.

7. A battery pack, characterized in that: A battery comprising at least two batteries according to any one of claims 1 to 6.

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