Cover plate assembly and battery pack

Abstract

The invention provides a cover plate assembly and a battery pack. The cover plate assembly comprises a cover plate, a pole, a first sealing element and a second sealing element. The cover plate comprises a first metal piece and a second metal piece sleeved outside the first metal piece. The first metal piece is provided with a through hole. And the pole is arranged in the through hole in a penetrating manner. The first sealing piece is arranged between the pole and the first metal piece; and the second sealing piece is connected with the first metal piece, or the second metal piece, or the second sealing piece is arranged between the first metal piece and the second metal piece, or the second sealing piece is connected with the pole. The second sealing piece is configured to prevent the electrolyte from flowing between the first metal piece and the second metal piece. Therefore, electrochemical corrosion caused by the fact that the electrolyte intrudes into the area between the first metal piece and the second metal piece can be prevented, the safety of the cover plate assembly is improved, and the service life of the cover plate assembly is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a cover plate assembly and a battery pack. Background Art

[0002] The mechanical strength and sealing of battery structural components are closely related to the battery life. In related technologies, battery structural components mostly use fluororubber as a sealing material, but fluororubber has poor aging resistance. When exposed to electrolyte and high temperature and high humidity environments for a long time, it is prone to aging and failure, which eventually leads to battery failure. Currently, there are structures that use glass seals to seal the cover assembly. Due to the high molding temperature of glass, the cover is formed of two metals. When the electrolyte leaks to the cover position, electrochemical corrosion will form at the connection between the two metals, affecting the service life of the cover assembly. Summary of the Invention

[0003] Embodiments of the present invention provide a cover plate assembly and a battery pack, which can improve the sealing performance between a first metal member and a second metal member, and prevent electrochemical corrosion between the first metal member and the second metal member due to the intrusion of electrolyte.

[0004] In a first aspect, an embodiment of the present invention provides a cover plate assembly, comprising:

[0005] The cover plate includes a first metal member and a second metal member sleeved on the outside of the first metal member, wherein the first metal member is provided with a through hole;

[0006] A pole, passing through the through hole;

[0007] a first sealing member, provided between the pole and the first metal member;

[0008] A second seal is connected to the first metal part, or connected to the second metal part, or arranged between the first metal part and the second metal part, or connected to the pole, and the second seal is configured to block the electrolyte from flowing between the first metal part and the second metal part.

[0009] In one embodiment, the first sealing member includes a first extension portion and a second extension portion, the first extension portion is sleeved outside the pole and located in the through hole, and the second extension portion is sleeved outside the first extension portion and connected to the first metal member.

[0010] In one embodiment, the first metal member is provided with a concave platform, and the second extension portion is disposed in the concave platform.

[0011] In one embodiment, a first connecting structure is provided between the first sealing member and the pole.

[0012] In one embodiment, the first connection structure includes a first groove and a first protrusion, one of the first groove and the first protrusion is arranged on the hole wall surface of the through hole, and the other is arranged on the outer peripheral surface of the pole, wherein the first protrusion is clamped in the first groove.

[0013] In one embodiment, a second connecting structure is provided between the first sealing component and the first metal component.

[0014] In one embodiment, the second connection structure includes a second groove and a second protrusion, one of the second groove and the second protrusion is arranged on the outer peripheral surface of the first sealing component, and the other is arranged on the inner peripheral surface of the first metal component, wherein the second protrusion is clamped in the second groove.

[0015] In one embodiment, the first metal part includes a first main body portion and a first connecting portion connected to the outer periphery of the first main body portion, and the second metal part includes a second main body portion and a second connecting portion connected to the inner periphery of the second main body portion, wherein the first connecting portion overlaps the second connecting portion.

[0016] In one embodiment, the second sealing member is disposed between the first body portion and the second connecting portion.

[0017] In one embodiment, the first body portion has a first surface configured to face the electrode assembly, the second connecting portion has a second surface configured to face the electrode assembly, and the second seal has a third surface configured to face the electrode assembly, wherein the second surface is located between the first surface and the second surface.

[0018] In one embodiment, the second sealing member further has a fourth surface facing away from the electrode assembly, and the fourth surface abuts against the first connecting portion.

[0019] In one embodiment, a welding layer is provided between the first connecting portion and the second connecting portion.

[0020] In one embodiment, a heating groove is provided on a surface of one of the first connecting portion and the second connecting portion facing away from the other, and the heating groove extends along the circumference of the cover plate, wherein the welding layer corresponds to the heating groove.

[0021] In one embodiment, along the radial direction of the cover plate, a first gap is formed between the first connecting portion and the second main body portion; and / or a second gap is formed between the second connecting portion and the first main body portion.

[0022] In one embodiment, the first connecting portion and the second connecting portion are riveted.

[0023] In one embodiment, the cover plate assembly further comprises:

[0024] An insulating member is sleeved on the pole, and the insulating member is connected to the first metal member and the second metal member on a side facing the electrode assembly.

[0025] In one embodiment, the second sealing member is disposed between the insulating member and the first metal member; and / or the second sealing member is disposed between the insulating member and the first sealing member.

[0026] In one embodiment, the second seal is disposed between the inner circumference of the insulating member and the outer circumference of the pole; and / or the second seal is disposed on the side of the insulating member facing the electrode assembly, and the second seal is annularly disposed on the pole.

[0027] In one embodiment, the cover plate assembly further comprises:

[0028] The current collector is welded to the side of the pole facing the electrode assembly.

[0029] In one embodiment, a connecting layer is provided on the side of the pole facing the electrode assembly, and the connecting layer is welded to the current collector, wherein the pole is made of a first metal material, the current collector and the connecting layer are both made of a second metal material, and the first metal material and the second metal material are different.

[0030] In one embodiment, a protective layer is provided on a side of the current collecting member facing away from the pole, and the protective layer covers a welding area between the current collecting member and the pole.

[0031] In one embodiment, the second metal member is configured with a reinforcing rib protruding in a direction away from the electrode assembly.

[0032] In one embodiment, the reinforcing rib is arched in a direction away from the electrode assembly to form a gas storage tank.

[0033] In one embodiment, the first sealing member is a rigid sealing member, and the second sealing member is a flexible sealing member or a sealing adhesive layer.

[0034] In a second aspect, an embodiment of the present invention provides a battery pack including the above-mentioned cover plate assembly.

[0035] In an embodiment of the present invention, the sealing between the pole and the first metal part is achieved by a first seal, and the electrolyte is blocked from reaching between the first metal part and the second metal part by setting a second seal to prevent the electrolyte from invading the area between the first metal part and the second metal part and causing electrochemical corrosion, thereby improving the safety and service life of the cover assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 is one of the cross-sectional views of the cover plate assembly provided by an embodiment of the present invention;

[0038] Figure 2 This is a second cross-sectional view of the cover plate assembly provided by an embodiment of the present invention;

[0039] Figure 3 This is a third cross-sectional view of the cover plate assembly provided by an embodiment of the present invention;

[0040] Figure 4 This is a fourth cross-sectional view of the cover plate assembly provided by an embodiment of the present invention;

[0041] Figure 5 This is a fifth cross-sectional view of the cover plate assembly provided by an embodiment of the present invention;

[0042] Figure 6 This is the sixth cross-sectional view of the cover plate assembly provided by an embodiment of the present invention;

[0043] Figure 7 This is the seventh cross-sectional view of the cover plate assembly provided by an embodiment of the present invention;

[0044] Figure 8 This is the eighth cross-sectional view of the cover plate assembly provided by an embodiment of the present invention.

[0045] Description of reference numerals:

[0046] 1. Cover plate; 11. First metal member; 111. Through hole; 112. Concave platform; 113. First body portion; 114. First connecting portion; 12. Second metal member; 121. Second body portion; 122. Second connecting portion; 124. Reinforcement rib; 125. Gas storage tank; 13. Welding layer; 14. Heating tank; 15. First gap; 16. Second gap; 17. Insulator; 18. Current collector; 181. Protective layer;

[0047] 2. Pole; 21. First column; 22. Second column; 23. Connecting layer;

[0048] 3. First sealing member; 31. First extension portion; 32. Second extension portion;

[0049] 4. Second sealing member;

[0050] 5. First connecting structure; 51. First groove; 52. First protrusion;

[0051] 6. Second connecting structure; 61. Second groove; 62. Second protrusion. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in 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. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In the present invention, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inside" and "outside" refer to the outline of the device.

[0053] First, see Figures 1 to 8 , an embodiment of the present invention provides a cover plate assembly, comprising:

[0054] The cover plate 1 includes a first metal member 11 and a second metal member 12 sleeved on the first metal member 11. The first metal member 11 is provided with a through hole 111.

[0055] The pole 2 is inserted into the through hole 111;

[0056] A first sealing member 3 is provided between the pole 2 and the first metal member 11;

[0057] The second sealing member 4 is connected to the first metal member 11, or connected to the second metal member 12, or arranged between the first metal member 11 and the second metal member 12, or connected to the pole 2. The second sealing member 4 is configured to block the electrolyte from flowing between the first metal member 11 and the second metal member 12.

[0058] In an embodiment of the present application, the sealing between the pole 2 and the first metal part 11 is achieved by the first seal 3, and the electrolyte is blocked from reaching between the first metal part 11 and the second metal part 12 by setting the second seal 4 to prevent the electrolyte from invading the area between the first metal part 11 and the second metal part 12 and causing electrochemical corrosion, thereby improving the safety and service life of the cover assembly.

[0059] It will be understood that the through-hole 111 in the cover plate 1 is used to mount the pole 2, creating a gap between the pole 2 and the cover plate 1. The first seal 3 is used to seal this gap. The axial direction of the pole 2 is the direction in which it is inserted into the through-hole 111, and the radial direction of the pole 2 is perpendicular to its axial direction. The first seal 3 is annular and disposed between the pole 2 and the cover plate 1. The inner and outer circumferences of the first seal 3 contact the pole 2 and cover plate 1, respectively, and interact with each other to secure the first seal 3 between the pole 2 and the cover plate 1.

[0060] The thickness of the first seal 3 along the radial direction of the pole 2 is set to 1 mm (millimeter) to 5 mm. The thickness of the first seal 3 along the radial direction of the pole 2 is the distance between the inner circumference and the outer circumference of the first seal 3. By limiting the thickness of the first seal 3 along the radial direction of the pole 2, the first seal 3 can be more stably fixed between the pole 2 and the cover plate 1, and the processing and forming of the first seal 3 can be facilitated.

[0061] As an example, the thickness of the first seal 3 along the radial direction of the pole 2 can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, or any value therebetween. The first seal 3 can be formed by injecting a molten rigid sealing material into the gap between the pole 2 and the cover plate 1 and then solidifying the material. The central axes of the through hole 111, the pole 2, and the first seal 3 are collinear.

[0062] In one embodiment, the height of the contact surface between the first sealing member 3 and the cover plate 1 along the axial direction of the pole 2 is 1 mm to 5 mm.

[0063] It can be understood that by controlling the height of the contact surface between the first seal 3 and the cover plate 1 along the axial direction of the pole 2, the first seal 3 can be fully contacted with the cover plate 1, so that the first seal 3 is more stably fixed between the pole 2 and the cover plate 1, while controlling the amount of material used for the first seal 3 and the internal space of the battery occupied.

[0064] As an example, the height of the contact surface between the first sealing member 3 and the cover plate 1 along the axial direction of the pole 2 can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc., or any value in between.

[0065] In one embodiment, the thickness of the first sealing member 3 along the axial direction of the pole 2 is set to 1 mm to 5 mm.

[0066] It can be understood that by controlling the thickness of the first seal 3 along the axial direction of the pole 2 , the first seal 3 can be in sufficient contact with the pole 2 , so that the first seal 3 is more stably fixed between the pole 2 and the cover plate 1 .

[0067] As an example, the thickness of the first sealing member 3 along the axial direction of the pole 2 can be set to 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, or any value therebetween.

[0068] In one embodiment, the top surface of the cover plate 1 is not lower than the top surface of the first sealing member 3 .

[0069] As can be understood, the cover plate 1 is used to seal a housing with one end open. The side of the cover plate 1 facing the housing is the bottom surface, and the side of the cover plate 1 facing away from the housing is the top surface. Accordingly, the side of the first sealing member 3 facing the housing is the bottom surface, and the side of the first sealing member 3 facing away from the housing is the top surface. By ensuring that the top surface of the cover plate 1 is not lower than the top surface of the first sealing member 3, the molten rigid sealing material is prevented from overflowing onto the cover plate 1 during injection and formation of the first sealing member 3, thereby facilitating the formation of the first sealing member 3.

[0070] In one embodiment, the pole 2 includes a first column 21 and a second column 22 connected to the bottom of the first column 21, and the outer periphery of the first column 21 exceeds the outer periphery of the second column 22; wherein the second column 22 is arranged in the through hole 111, and the first sealing member 3 is sleeved outside the second column 22.

[0071] It can be understood that the second column 22 is used to be installed in the through hole 111, and the outer periphery of the first column 21 exceeds the outer periphery of the second column 22, so that the second column 22 can be installed in the through hole 111. At the same time, the top surface of the pole 2 used for welding (the side of the first column 21 facing away from the second column 22) has a larger area, thereby facilitating the welding of the pole 2.

[0072] As an example, the first column 21 and the second column 22 are integrally formed.

[0073] In one embodiment, the thickness of the first column 21 along its axial direction is 0.2 mm to 3 mm.

[0074] It can be understood that the axial direction of the first column 21 is the same as the axial direction of the pole 2. By controlling the axial thickness of the first column 21, the pole 2 can be prevented from being welded through, thereby improving the reliability of welding.

[0075] As an example, the thickness of the first column 21 along the axial direction thereof may be 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3 mm, or any value therebetween.

[0076] In one embodiment, a gap is provided between the first sealing member 3 and the first cylinder 21 in the axial direction of the first cylinder 21 .

[0077] It can be understood that welding operations are required during the process of assembling batteries into battery packs. During welding, the side of the first column 21 facing away from the second column 22 will be fixed and welded. By providing a gap between the first seal 3 and the first column 21 in the axial direction of the first column 21, the first seal 3 can be prevented from being squeezed, thereby preventing the first seal 3 from cracking.

[0078] In one embodiment, a plurality of through holes 111 , a plurality of poles 2 and a plurality of first sealing members 3 are provided.

[0079] It is understood that by providing multiple through-holes 111, multiple first seals 3, and multiple poles 2, the size of a single through-hole 111, a single pole 2, and a single first seal 3 can be reduced, thereby improving the overall structural strength and stability of the cover 1. The number of poles 2 can be set according to their size, and the number of through-holes 111 and first seals 3 can be the same as the number of poles 2.

[0080] As an example, two, three, four, etc. through holes 111 , poles 2 , and first sealing members 3 may be provided respectively.

[0081] In one embodiment, the plurality of poles 2 are evenly distributed around the cover plate 1 .

[0082] It can be understood that the multiple poles 2 are evenly distributed around the cover plate 1. By evenly distributing the multiple poles 2 around the cover plate 1, the overall structural strength and stability of the cover plate 1 can be improved.

[0083] In one embodiment, the total area of ​​the top surfaces of the plurality of poles 2 accounts for 5% to 50% of the area of ​​the top surface of the cover plate 1 .

[0084] It can be understood that the top surface of the pole 2 is used for welding. By making the sum of the top surface areas of multiple poles 2 account for 5% to 50% of the top surface area of ​​the cover plate 1, the pole 2 can have a larger welding area, thereby improving the welding strength and welding reliability. At the same time, the pressure from the pole 2 on the cover plate 1 can be controlled to prevent the mechanical properties of the cover plate 1 from being degraded.

[0085] As an example, the sum of the top surface areas of the plurality of poles 2 may account for 5%, 5%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc., of the top surface area of ​​the cover 1 .

[0086] In one embodiment, the first sealing member 3 includes a first extension portion 31 and a second extension portion 32 . The first extension portion 31 is sleeved outside the pole 2 and located in the through hole 111 . The second extension portion 32 is sleeved outside the first extension portion 31 and connected to the first metal member 11 .

[0087] It can be understood that the first extension portion 31 is sleeved outside the pole 2, and its inner and outer circumferential surfaces are in contact with the pole 2 and the cover plate 1 respectively, which will apply axial pressure to the pole 2. By connecting the second extension portion 32 sleeved outside the first extension portion 31 to the cover plate 1, the cover plate 1 can provide support force to the second extension portion 32, thereby providing support force for the first extension portion 31, thereby alleviating the axial pressure of the pole 2 and improving the reliability of the seal.

[0088] In one embodiment, the first extension portion 31 and the second extension portion 32 are integrally formed.

[0089] In one embodiment, the first metal member 11 is provided with a recessed platform 112 , and the second extension portion 32 is disposed in the recessed platform 112 .

[0090] It is understood that the rigid seal can be formed by injecting molten rigid sealing material into the gap between the pole 2 and the cover plate 1 and then allowing it to solidify. By providing a recessed platform 112 on the cover plate 1, after the pole 2 is installed in the first through hole 111, the molten rigid sealing material is injected into the gap between the pole 2 and the cover plate 1. This allows the first extension 31 and the second extension 32 to be integrally formed, thereby facilitating the processing and forming of the rigid seal and preventing the molten rigid sealing material from overflowing onto the cover plate 1 during the injection process. By arranging the second extension 32 within the recessed platform 112, the second extension 32 and the cover plate 1 can be overlapped.

[0091] In one embodiment, a first connecting structure 5 is provided between the first sealing member 3 and the pole 2 .

[0092] It is understood that the provision of the first connecting structure 5 between the first seal 3 and the pole 2 further ensures a reliable connection between the two and prevents relative displacement of the first seal 3 and the pole 2 in the axial direction of the cover plate 1, thereby ensuring connection accuracy. Furthermore, the first connecting structure 5 provides support for the first seal 3, thereby alleviating axial pressure on the pole 2 and improving the sealing reliability of the first seal 3.

[0093] In one embodiment, the first connecting structure 5 includes a first groove 51 and a first protrusion 52, one of the first groove 51 and the first protrusion 52 is arranged on the hole wall surface of the through hole 111, and the other is arranged on the outer peripheral surface of the pole 2, wherein the first protrusion 52 is clamped in the first groove 51.

[0094] It can be understood that the first groove 51 and the first protrusion 52 are engaged with each other so that the pole 2 and the first seal 3 can be positioned relative to each other in the axial direction, thereby preventing the first seal 3 and the pole 2 from being displaced relative to each other in the axial direction of the cover plate 1 and ensuring connection accuracy.

[0095] In some embodiments, the first protrusion 52 is annular, and the first groove 51 is an annular groove. Alternatively, the first protrusion 52 is circumferentially spaced apart and at least two first grooves 51 are also circumferentially spaced apart.

[0096] As an example, the inner circumference of the first sealing member 3 is provided with a first groove 51. The outer circumference of the pole 2 is provided with a first protrusion 52. The first protrusion 52 is formed integrally with the pole 2.

[0097] As an example, the inner circumference of the first sealing member 3 is provided with a first protrusion 52 , and the outer circumference of the pole 2 is provided with a first groove 51 . The first protrusion 52 and the first sealing member 3 are integrally formed.

[0098] In one embodiment, a second connecting structure 6 is provided between the first sealing component 3 and the first metal component 11 .

[0099] It is understood that the provision of the second connection structure 6 between the first seal 3 and the first metal member 11 further ensures a reliable connection between the two and prevents relative displacement of the first seal 3 and the first metal member 11 in the axial direction of the cover plate 1, thereby ensuring connection accuracy. Furthermore, the second connection structure 6 provides support for the first seal 3, thereby alleviating axial pressure on the pole 2 and improving the sealing reliability of the first seal 3.

[0100] In one embodiment, the second connecting structure 6 includes a second groove 61 and a second protrusion 62, one of the second groove 61 and the second protrusion 62 is arranged on the outer peripheral surface of the first sealing component 3, and the other is arranged on the inner peripheral surface of the first metal component 11, wherein the second protrusion 62 is clamped in the second groove 61.

[0101] It can be understood that the second groove 61 and the second protrusion 62 are clamped together so that the first seal 3 and the first metal part 11 can be positioned relative to each other in the axial direction, thereby preventing the first seal 3 and the first metal part 11 from relative displacement in the axial direction of the cover plate 1 and ensuring the connection accuracy.

[0102] In some embodiments, the second protrusion 62 is annular, and the second groove 61 is an annular groove. Alternatively, the second protrusion 62 is circumferentially spaced apart and at least two second grooves 61 are also circumferentially spaced apart.

[0103] As an example, the outer circumference of the first sealing member 3 is provided with a second groove 61 , and the inner circumference of the first metal member 11 is provided with a second protrusion 62 , wherein the second protrusion 62 and the first metal member 11 are integrally formed.

[0104] As an example, the outer circumference of the first sealing member 3 is provided with a second protrusion 62 , and the inner circumference of the first metal member 11 is provided with a second groove 61 . The second protrusion 62 and the first sealing member 3 are integrally formed.

[0105] In one embodiment, the dimension of the first groove 51 and / or the first protrusion 52 along the axial direction of the pole 2 is 0.5 mm-5 mm, and the dimension of the first groove 51 and / or the first protrusion 52 along the radial direction of the pole 2 is 0.2 mm-1.5 mm.

[0106] It can be understood that by controlling the axial dimensions of the first groove 51 and the first protrusion 52 along the pole 2 and the radial dimensions along the pole 2, the first seal 3 can be fully contacted with the cover plate 1 through the first groove 51 and the first protrusion 52, so that the cover plate 1 can provide sufficient support force for the first seal 3, thereby alleviating the axial pressure of the pole 2, improving the sealing reliability of the first seal 3, and at the same time facilitating the formation of the first groove 51 and the first protrusion 52, and ensuring the overall pressure-bearing capacity of the cover plate 1.

[0107] As an example, the size of the first groove 51 along the axial direction of the pole 2 can be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc.

[0108] As an example, the dimension of the first protrusion 52 along the axial direction of the pole 2 may be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc.

[0109] In one embodiment, the second groove 61 and / or the second protrusion 62 has an axial dimension of 0.5 mm to 5 mm along the pole 2 , and a radial dimension of 0.2 mm to 1.5 mm along the pole 2 .

[0110] It can be understood that by controlling the axial dimensions of the second groove 61 and the second protrusion 62 along the pole 2 and the radial dimensions of the pole 2, the first seal 3 can be fully contacted with the pole 2 through the second groove 61 and the second protrusion 62, thereby providing sufficient support force for the first seal 3 through the second groove 61 and the second protrusion 62, thereby alleviating the axial pressure of the pole 2, improving the sealing reliability of the first seal 3, and facilitating the formation of the second groove 61 and the second protrusion 62, and ensuring the overall pressure-bearing capacity of the pole 2.

[0111] As an example, the size of the second groove 61 along the axial direction of the pole 2 may be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc.

[0112] As an example, the size of the second protrusion 62 along the axial direction of the pole 2 may be 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc.

[0113] In one embodiment, the first metal component 11 includes a first main body portion 113 and a first connecting portion 114 connected to the outer periphery of the first main body portion 113, and the second metal component 12 includes a second main body portion 121 and a second connecting portion 122 connected to the inner periphery of the second main body portion 121, wherein the first connecting portion 114 and the second connecting portion 122 are overlapped.

[0114] It can be understood that the fixed connection between the first metal component 11 and the second metal component 12 is achieved by overlapping the first connecting portion 114 and the second connecting portion 122 .

[0115] Exemplarily, the first connection portion 114 is located above the second connection portion 122 . Alternatively, the first connection portion 114 is located below the second connection portion 122 .

[0116] In some embodiments, the first body portion 113 and the first connecting portion 114 are integrally formed, and both are configured in a circular ring shape.

[0117] In some embodiments, the second body portion 121 and the second connecting portion 122 are integrally formed, and both are configured in a circular ring shape.

[0118] In one embodiment, the second sealing member 4 is disposed between the first body portion 113 and the second connecting portion 122 .

[0119] It is understandable that the second sealing member 4 is disposed between the first body portion 113 and the second connecting portion 122 to seal the gap between the first metal member 11 and the second metal member 12 to prevent the electrolyte from penetrating between the first metal member 11 and the second metal member 12 and causing electrochemical corrosion.

[0120] In one embodiment, the first body portion 113 has a first surface configured to face the electrode assembly, the second connecting portion 122 has a second surface configured to face the electrode assembly, and the second sealing member 4 has a third surface configured to face the electrode assembly, wherein the second surface is located between the first surface and the second surface.

[0121] It is understood that by disposing the second sealing member 4 between the first metal member 11 and the second metal member 12 and positioning the third surface between the first and second surfaces, the second sealing member 4 not only prevents the connection between the first and second metal members 11, 12 from contacting the electrolyte, thereby preventing galvanic corrosion and thus ensuring the structural strength of the first and second metal members 11, 12, but also increases the mating area between the second sealing member 4 and the other metal member 12 while controlling the thickness of one of the two, thereby improving the positional stability of the second sealing member 4. This improves the reliability of the cover assembly.

[0122] In some embodiments, along the radial direction of the second metal member 12 , the thickness of the second sealing member 4 is set to be 0.3 mm-0.8 mm.

[0123] By limiting the thickness of the second seal 4, the second seal 4 can have sufficient thickness to meet the sealing requirements between the first metal part 11 and the second metal part 12, and the radial dimension occupied by the second seal 4 can be controlled to avoid the radial dimension occupied by the second seal 4 being too large and affecting the arrangement of the first metal part 11 and the second metal part 12.

[0124] Furthermore, when the radial gap size between the first metal member 11 and the second metal member 12 is constant, controlling the thickness of the second seal 4 can also prevent the second seal 4 from being subjected to excessive pressure, thereby improving the service life of the second seal 4 .

[0125] In some embodiments, along the axial direction of the second metal member 12 , the height of the second sealing member 4 is set to 0.3 mm-2 mm.

[0126] By limiting the height of the second seal 4, the second seal 4 can have a sufficient height to meet the sealing requirements between the first metal part 11 and the second metal part 12, and the height of the second seal 4 can be controlled to avoid its height being too high and causing unnecessary increase in material costs.

[0127] It can be understood that in order to improve the sealing performance of the second seal 4 on the fitting part between the first metal part 11 and the second metal part 12, the height of the second seal 4 is not less than the height dimension of the second metal part 12 and the fitting part between the second metal part 12 and the second metal part 12.

[0128] In one embodiment, the second sealing member 4 further has a fourth surface facing away from the electrode assembly, and the fourth surface abuts against the first connecting portion 114 .

[0129] Through the above arrangement, the mating surface between the second sealing member 4 and the first metal member 11 and / or the second metal member 12 can be increased, thereby improving the stability of the mating between the second sealing member 4 and the first metal member 11 and / or the second metal member 12.

[0130] In one embodiment, a welding layer 13 is disposed between the first connection portion 114 and the second connection portion 122 .

[0131] For example, the material of the solder layer may be solder, welding wire, welding machine, etc. The solder may be tin-based solder, silver-based solder, copper-based solder, or aluminum-based solder. For example, when the first metal member 11 is made of aluminum and the second metal member 12 is made of stainless steel, the solder may be an aluminum-based solder, such as AL-12Si or Al-Si-Mg.

[0132] In some embodiments, the material of the solder layer includes solder. It is understood that solder has a relatively low melting point. For example, the melting point of soft solder is generally below 450°C. This allows the soldering process to be performed at a relatively low temperature, thereby preventing high temperatures from affecting the properties of the first metal member 11 and the second metal member 12 and reducing deformation and stress in the cover plate 1.

[0133] In this embodiment, a solder layer is provided at the weld site between the first metal member 11 and the second metal member 12, thereby forming a transition layer between the first metal member 11 and the second metal member 12. This allows the solder layer to undergo metallurgical reactions with the first metal member 11 and the second metal member 12, promoting atomic diffusion and bonding to form a welded structure. This reduces the difficulty of welding dissimilar metals and improves the weld quality between the first metal member 11 and the second metal member 12.

[0134] Along the axial direction of the cover plate 1 , the thickness of the solder layer is set to 0.05 mm-3 mm.

[0135] In this embodiment, by limiting the thickness of the solder layer, on the one hand, it can avoid the solder layer being too thin, which would result in insufficient metallurgical bonding between the first metal part 11 and the second metal part 12; on the other hand, it can avoid the solder layer being too thick, which would result in more heating time being required, thereby improving welding efficiency.

[0136] Along the axial direction of the cover plate 1 , the thickness of the solder layer is set to 0.1 mm-1 mm.

[0137] In this embodiment, by limiting the thickness of the solder layer, it is possible to ensure that there is sufficient solder between the first metal part 11 and the second metal part 12 to facilitate the formation of effective metallurgical bonding, and the time required for welding between the first metal part 11 and the second metal part 12 can be controlled, which is conducive to improving welding efficiency.

[0138] Illustratively, the thickness of the solder layer may be: 0.1 mm, 0.12 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.22 mm, 0.25 mm, 0.28 mm, 0.3 mm, 0.32 mm, 0.35 mm, 0.38 mm, 0.4 mm, 0.42 mm, 0.45 mm, 0.48 mm, 0.5 mm, 0.52 mm, 0.55 mm, 0.58 mm, 0.6 mm, 0.62 mm, 0.65 mm, 0.68 mm, 0.7 mm, 0.72 mm, 0.75 mm, 0.78 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, or 1.0 mm.

[0139] In the radial direction of the cover plate 1, the width of the solder layer is greater than or equal to 1.8 mm. In this way, the solder layer can have a larger width, which is beneficial for implementing the solder coating process and improving manufacturing efficiency.

[0140] It is understood that when the first metal member 11 and the second metal member 12 are bonded together, an adhesive layer is provided at the overlapped portion between the first metal member 11 and the second metal member 12, and the width of the adhesive layer in the radial direction of the cover plate 1 is not less than 1.8. This allows the adhesive layer to have a larger width, facilitating the adhesive layer coating process and improving manufacturing efficiency.

[0141] In one embodiment, a heating groove 14 is provided on a surface of one of the first connecting portion 114 and the second connecting portion 122 facing away from the other. The heating groove 14 extends along the circumference of the cover plate 1 , wherein the welding layer 13 corresponds to the heating groove 14 .

[0142] Specifically, the heating groove 1413 extends in a ring shape along the circumference of the cover plate 1100 .

[0143] It is understood that the inner wall of the heating tank 1413 is configured to directly contact the heat source to heat the welding portion between the first metal member 1111 and the second metal member 1212. For example, the heating resistance wire can be configured as a ring structure and placed in the heating tank 1413.

[0144] In this embodiment, by providing a heating tank 1413, a heat source can be placed within the heating tank 1413 so that the heat from the heat source can be more concentratedly transferred to the weld between the first metal member 1111 and the second metal member 1212, thereby improving heating efficiency and facilitating greater precision in controlling the heating temperature. This improves the weld quality between the first metal member 1111 and the second metal member 1212.

[0145] In one embodiment, along the radial direction of the cover plate 1 , a first gap 15 is formed between the first connecting portion 114 and the second body portion 121 ; and / or a second gap 16 is formed between the second connecting portion 122 and the first body portion 113 .

[0146] It is understood that since the first connecting portion 114 and the second connecting portion 122 are connected by welding, a first gap 15 is formed between the first connecting portion 114 and the second main portion 121, and / or a second gap 16 is formed between the second connecting portion 122 and the first main portion 113. Thus, the first gap 15 and the second gap 16 can accommodate the differential expansion between the first metal member 11 and the second metal member 12, thereby reducing the thermal expansion and compression stress between the first and second metal members 11 and 12. This improves the stress state of the connection between the first and second metal members 11 and 12 during thermal expansion, thereby enhancing the reliability of the connection between the first and second metal members 11 and 12.

[0147] For example, when the first metal part 11 and the second metal part 12 are welded, by setting the first gap 15 and the second gap 16 , the welding stress between the first metal part 11 and the second metal part 12 can be improved, thereby improving the welding quality of the first metal part 11 and the second metal part 12 .

[0148] For another example, when the battery cell is charged or discharged, by providing the first gap 15 and the second gap 16 , the abutment stress between the first metal member 11 and the second metal member 12 can be improved, thereby improving the reliability of the connection between the first metal member 11 and the second metal member 12 .

[0149] In some embodiments, the first gap 15 and the second gap 16 have the same width, ranging from 0.05 mm to 0.2 mm. This prevents a gap width that is too small, which would significantly reduce the thermal expansion and compression stress between the first metal member 11 and the second metal member 12, while also preventing a gap width that is too large, which would affect the strength of the cover plate 1. This improves the reliability of the connection between the first metal member 11 and the second metal member 12.

[0150] In one embodiment, the first connection portion 114 and the second connection portion 122 are riveted.

[0151] It can be understood that the first metal part 11 and the second metal part 12 are riveted to each other through the first connecting part 114 and the second connecting part 122. On the basis of realizing direct connection of dissimilar metals, a mechanical structural interlocking can be formed between the first metal part 11 and the second metal part 12 based on the plastic deformation achieved by riveting, so that the first metal part 11 and the second metal part 12 can be stably connected as one, so as to improve the reliability of the connection between the first metal part 11 and the second metal part 12.

[0152] It can be understood that riveting is a way of connecting two or more parts together by applying force to produce plastic deformation. Depending on the form of riveting, riveting can be nail riveting or nailless riveting. Nail riveting mainly refers to the penetration of multiple parts by rivets, and deforming the tail of the rivet to clamp multiple parts between the head and tail of the rivet. Nailless riveting can be divided into self-piercing riveting (that is, one part penetrates another part to form a mechanical interlock), pressure interlocking riveting (through die extrusion to make the material flow locally to form a concave and convex bonding structure), folding riveting (that is, folding the edge of one part to wrap another part) and friction riveting (that is, softening the material by rotating friction to achieve connection).

[0153] It is understood that when nail riveting is selected, a sealing member, such as a sealant or an elastic sealing ring, may be provided at the mating portion between the first metal member 11 and the second metal member 12 to improve the sealing performance. When nail-free riveting is selected, hem riveting may be optionally employed, whereby one of the first metal member 11 and the second metal member 12 wraps around the edge of the other, thereby achieving both a connection between the first metal member 11 and the second metal member 12 and a tight fit between the first metal member 11 and the second metal member 12 to achieve a seal.

[0154] In some embodiments, the outer circumference of the first connection portion 114 engages with the inner circumference of the second connection portion 122 .

[0155] In some embodiments, a bite edge is provided on the outer periphery of the first connection portion 114. A riveted edge may be provided on the inner periphery of the second connection portion 122. The bite edge is embedded in the riveted edge.

[0156] In one embodiment, the cover plate assembly further comprises:

[0157] The insulating member 17 is sleeved on the pole 2 and is connected to the first metal member 11 and the second metal member 12 on a side facing the electrode assembly.

[0158] It is understood that the primary function of insulator 17 is to ensure electrical insulation between the electrode assembly and the conductive sheet, preventing possible short circuits or other electrical failures. Insulator 17 also provides structural support, axially abutting the electrode assembly to ensure its stability within the housing and prevent shaking caused by vibration or external forces.

[0159] In some embodiments, the insulating member 17 is lower plastic.

[0160] In some embodiments, a slot is provided on the side of the first metal member 11 and / or the second metal member 12 facing the electrode assembly, and a block is provided on the side of the insulating member 17 facing away from the electrode assembly. The block is engaged in the slot.

[0161] In some embodiments, the insulating member 17 is integrally injection-molded with the first metal member 11 and the second metal member 12 , so that the insulating member 17 is injection-molded and connected to the first metal member 11 and the second metal member 12 .

[0162] In one embodiment, the second sealing member 4 is disposed between the insulating member 17 and the first metal member 11 ; and / or the second sealing member 4 is disposed between the insulating member 17 and the first sealing member 3 .

[0163] In this embodiment, by disposing the second sealing member 4 between the insulating member 17 and at least one of the first metal member 11 and the first sealing member 3, electrolyte can be effectively prevented from flowing from the mating portion between the insulating member 17 and the terminal 2 into the space between the first metal member 11 and the second metal member 12. This prevents galvanic corrosion between the first metal member 11 and the second metal member 12, thereby ensuring the structural strength of the first metal member 11 and the second metal member 12, and thus improving the structural strength of the cover plate assembly.

[0164] In addition, by arranging a second seal 4 between the insulating part 17 and at least one of the second seal 4 and the first metal part 11, the strength of the cover assembly close to the pole 2 can also be enhanced, which is beneficial to improving the deformation resistance of the cover assembly, so that the cover assembly can withstand a greater pressure inside the battery cell, which is beneficial to improving the reliability of the battery cell.

[0165] Exemplarily, the second sealing member 4 is disposed between the insulating member 17 and the first metal member 11 , thereby sealing the gap between the insulating member 17 and the first metal member 11 to prevent the electrolyte from flowing from the gap into between the first metal member 11 and the second metal member 12 .

[0166] Exemplarily, the second sealing member 4 is disposed between the insulating member 17 and the first sealing member 3 , thereby sealing the gap between the insulating member 17 and the first sealing member 3 to prevent the electrolyte from flowing from the gap into between the first metal member 11 and the second metal member 12 .

[0167] In one embodiment, two sides of the second sealing member 4 are respectively connected to the insulating member 17 and the first metal member 11. Along the axial direction of the pole 2, the height of the second sealing member 4 is set to 0.3 mm-0.5 mm.

[0168] In this embodiment, by limiting the height of the second sealing member 4, the second sealing member 4 can be made sufficiently tall to meet sealing requirements and prevent the electrolyte from flowing between the first metal member 11 and the second metal member 12. Furthermore, the height occupied by the second sealing member 4 can be controlled to prevent the second sealing member 4 from occupying a large portion of the height of the cover assembly and affecting the size of the first metal member 11. This improves the reliability of the cover assembly.

[0169] Moreover, when the distance between the insulating member 17 and the first metal member 11 is constant and the second sealing member 4 is a rubber ring, by controlling the height of the second sealing member 4 , the second sealing member 4 can be prevented from being subjected to excessive pressure, which is beneficial to improving the service life of the second sealing member 4 .

[0170] In one embodiment, two sides of the second sealing member 4 are respectively connected to the insulating member 17 and the first sealing member 3. Along the axial direction of the pole 2, the height of the second sealing member 4 is set to 0.3mm-0.5mm.

[0171] In this embodiment, by limiting the height of the second sealing member 4, the second sealing member 4 can be made sufficiently tall to meet sealing requirements and prevent the electrolyte from flowing between the first metal member 11 and the second metal member 12. Furthermore, the height occupied by the second sealing member 4 can be controlled to prevent the second sealing member 4 from occupying a large portion of the height of the cover assembly and affecting the size of the first metal member 11. This improves the reliability of the cover assembly.

[0172] Moreover, when the distance between the insulating member 17 and the first sealing member 3 is constant and the second sealing member 4 is a rubber ring, by controlling the height of the second sealing member 4, the second sealing member 4 can be prevented from being subjected to excessive pressure, which is beneficial to improving the service life of the second sealing member 4.

[0173] In one embodiment, the second seal 4 is disposed between the inner circumference of the insulating member 17 and the outer circumference of the pole 2; and / or, the second seal 4 is disposed on the side of the insulating member 17 facing the electrode assembly, and the second seal 4 is arranged around the pole 2.

[0174] It is understood that by providing the second sealing member 4 between the inner circumference of the insulating member 17 and the outer circumference of the terminal 2, it is possible to effectively prevent the electrolyte from flowing from the mating portion between the insulating member 17 and the terminal 2 into the space between the first metal member 11 and the second metal member 12. This prevents galvanic corrosion between the first metal member 11 and the second metal member 12, helps ensure the structural strength of the first metal member 11 and the second metal member 12, and thus improves the structural strength of the cover assembly.

[0175] Among them, the second sealing member 4 is arranged between the second metal member 12 and the current collecting member 18, which can effectively utilize the distance between the second metal member 12 and the current collecting member 18, thereby avoiding the setting of the second sealing member 4 causing the position of other components to need to be adjusted or affecting the height of the cover assembly, thereby simplifying the design of the cover assembly and ensuring the energy density of the battery cell.

[0176] It is understood that by arranging the second seal 4 on the side of the insulating member 17 facing the electrode assembly and the second seal 4 being arranged around the terminal 2, it is possible to effectively prevent the electrolyte from flowing from the mating portion between the insulating member 17 and the terminal 2 into the space between the first metal member 11 and the second metal member 12. In this way, galvanic corrosion between the first metal member 11 and the second metal member 12 can be avoided, which helps to ensure the structural strength of the first metal member 11 and the second metal member 12, thereby improving the structural strength of the cover plate assembly.

[0177] In one embodiment, the cover plate assembly further comprises:

[0178] The current collector 18 is welded to the side of the electrode column 2 facing the electrode assembly.

[0179] It is understood that the current collector 18 is used to connect the electrode assembly and is welded to the pole 2 to enable the electrode assembly to supply power and charge externally.

[0180] In one embodiment, a connecting layer 23 is provided on the side of the pole 2 facing the electrode assembly, and the connecting layer 23 is welded to the current collector 18, wherein the pole 2 is made of a first metal material, the current collector 18 and the connecting layer 23 are both made of a second metal material, and the first metal material and the second metal material are different.

[0181] It can be understood that the pole 2 is made of a first metal material, and the busbar and the connecting layer 23 are made of a second metal material. The difference between the first metal material and the second metal material can avoid the electrochemical reaction caused by the potential difference between different metals under the influence of the electrolyte during the operation of the battery, thereby increasing the electrochemical stability of the battery and improving the service life of the battery.

[0182] For example, when the busbar is pure copper or nickel-plated copper, the first metal material can be stainless steel, and the second metal material can be copper or nickel-plated copper. Pure copper has extremely high electrical conductivity. High electrical conductivity alone makes the battery's current transmission more efficient, reduces the battery's internal resistance, and can improve charging and discharging efficiency. Nickel-plated copper can take into account both electrical conductivity and antioxidant capacity, extending the battery's service life. This application does not limit the specific metal material, as long as the pole 2 is the first metal material, the busbar and the connecting layer 23 are the second metal material, and the first metal material and the second metal material are different.

[0183] In some embodiments, the thickness of the connecting layer 23 is no less than 5 microns. Specifically, the thickness of the connecting layer 23 can also be 6 microns, 6 microns, 7 microns, 6 microns, 8 microns, 9 microns, 10 microns, etc., which are not limited in this application. Setting the connecting layer 23 to be no less than 5 microns is primarily to ensure that the connecting layer 23 can provide a good connection effect, avoid damage to the metal material of the connecting layer 23 due to insufficient thickness, and adapt to the needs of various application environments.

[0184] In one embodiment, a protective layer 181 is provided on a side of the current collector 18 facing away from the pole 2 , and the protective layer 181 covers the welding area between the current collector 18 and the pole 2 .

[0185] When two or more dissimilar metals come into contact in a conductive medium, the different electrode potentials can create a corrosive galvanic cell, which can significantly reduce battery performance over the long term and may even lead to safety issues. In this application, a protective layer 181 is provided on the side of the weld facing away from the pole 2. This layer prevents electrolyte from contacting these welds, preventing corrosion and loss of the metal structure caused by galvanic cell reactions, and thus improving the battery's service life. Furthermore, the provision of protective layer 181 can also prevent frictional contact between the collector plate and the weld print, preventing metal shavings from friction that could cause a battery short circuit, thereby improving battery safety.

[0186] In some embodiments, the thickness of protective layer 181 is no less than 5 microns. Specifically, the thickness of protective layer 181 can also be 6 microns, 6 microns, 7 microns, 6 microns, 8 microns, 9 microns, 10 microns, etc., which are not limited in this application. Setting protective layer 181 to no less than 5 microns is primarily to ensure that protective layer 181 can provide a good isolation effect, avoid damage to protective layer 181 material due to insufficient thickness, and adapt to the needs of various application environments.

[0187] In some embodiments, protective layer 181 is made of an anti-corrosion material. Specifically, protective layer 181 can be polyvinylidene fluoride and its derivatives. Polyvinylidene fluoride has excellent corrosion resistance to most acids, bases, solvents, and salts in water. It is particularly stable against highly corrosive substances such as concentrated sulfuric acid, hydrofluoric acid, and chlorides. It also has good mechanical strength, toughness, and impact resistance, and can maintain long-term stable performance even in harsh environments.

[0188] The protective layer 181 can also be a polyacrylate compound, such as polyacrylic acid, sodium polyacrylate, etc., which has strong hydrophilicity. This hydrophilicity enables it to form a certain protective film in a corrosive environment, preventing water and corrosive media from directly contacting the substrate, thereby reducing the speed and intensity of corrosion.

[0189] Protective layer 181 can also be a modified epoxy resin adhesive, which can form strong bonds on a variety of substrates. Modification can improve its adaptability to different materials, especially its outstanding performance in bonding complex surfaces or porous materials. Modification can further enhance the chemical corrosion resistance of epoxy resin.

[0190] In some embodiments, the projection of the electrode 2 in the direction of the battery cell is located within the projection of the protective layer 181 in the direction of the battery cell. It is understood that when the area of ​​the protective layer 181 is larger than the bottom area of ​​the electrode 2, the protective layer 181 can cover a larger area around the electrode 2, effectively isolating it from electrolyte corrosion and extending the service life of the battery.

[0191] In one embodiment, the second metal member 12 is configured with a reinforcing rib 124 protruding in a direction away from the electrode assembly.

[0192] It is understandable that the reinforcing ribs 124 are constructed on the second metal member 12 to structurally strengthen the second metal member 12 to prevent the second metal member 12 from deforming during use and ensure that the second metal member 12 has sufficient structural strength.

[0193] In some embodiments, the reinforcing rib 124 is a structure integrally stamped and formed on the second metal component 12 .

[0194] In one embodiment, the reinforcing rib 124 arches in a direction away from the electrode assembly to form a gas storage tank 125 .

[0195] It is understood that by stamping the second metal member 12 to form a reinforcing rib 124 that arches away from the electrode assembly, a gas storage tank 125 can be formed on the inner side of the cover assembly. As the electrode assembly continues to charge and discharge, the gas generated can flow into the gas storage tank 125 to slow the expansion of the single battery cell.

[0196] In one embodiment, the first sealing member 3 is a rigid sealing member, and the second sealing member 4 is a flexible sealing member or a sealing adhesive layer.

[0197] It is understood that the rigid seal is disposed between the tab and the first metal member 11, thereby increasing the service life and sealing reliability of the first seal 3 and preventing leakage due to aging of the first seal 3 after long-term use. The second seal 4 is a flexible seal or sealant layer that seals the leakage channel between the first metal member 11 and the second metal member 12, preventing the electrolyte from flowing between the first metal member 11 and the second metal member 12 and causing electrochemical corrosion, thereby improving the safety and service life of the cover assembly.

[0198] In one embodiment, the first metal member 11 includes one or more of a stainless steel plate, a titanium plate, and a nickel plate, and the second metal member 12 is an aluminum plate.

[0199] It can be understood that the first seal 3 can be formed by injecting molten rigid sealing material into the gap between the pole 2 and the cover plate 1 and then solidifying it. Therefore, the melting point of the cover plate 1 in contact with the outer peripheral surface of the first seal 3 needs to be greater than the melting point of the rigid sealing material. By splitting the cover plate 1 into a first metal part 11 and a second metal part 12, the first metal part 11 can be made of a plate made of stainless steel, titanium, or nickel with a high melting point, so that it will not deform or melt when it comes into contact with the molten rigid sealing material. At the same time, the second metal part 12 is made of an aluminum plate to ensure the conductivity of the cover plate 1. Stainless steel plate, titanium plate, and nickel plate refer to plates comprising stainless steel, titanium, and nickel respectively. In addition to stainless steel, titanium, and nickel, other materials may also be contained.

[0200] In one embodiment, the first seal 3 is a glass seal.

[0201] It will be appreciated that the glass seal is made of glass, which has a lower melting point than stainless steel.

[0202] The pole 2 includes one or more of a stainless steel pole 2 , a titanium pole 2 , and a nickel pole 2 .

[0203] It is understood that the first seal 3 can be formed by injecting a molten rigid sealing material into the gap between the pole 2 and the cover plate 1 and then solidifying it. Therefore, the melting point of the pole 2 in contact with the inner circumference of the first seal 3 needs to be greater than the melting point of the rigid sealing material. The pole 2 can be made of a plate made of stainless steel, titanium metal, or nickel metal with a high melting point, so that it will not deform or melt when in contact with the molten rigid sealing material. The stainless steel pole 2, titanium pole 2, and nickel pole 2 refer to poles 2 whose materials include stainless steel, titanium metal, and nickel metal, respectively. In addition to stainless steel, titanium metal, and nickel metal, other materials may also be included.

[0204] In a second aspect, an embodiment of the present invention provides a battery pack including the above-mentioned cover plate assembly.

[0205] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A cover plate assembly, characterized in that: include: The cover plate (1) comprises a first metal member (11) and a second metal member (12) sleeved on the outside of the first metal member (11), wherein the first metal member (11) is provided with a through hole (111); A pole (2) is inserted into the through hole (111); A first sealing member (3) is provided between the pole (2) and the first metal member (11); A second sealing member (4) is connected to the first metal member (11), or connected to the second metal member (12), or arranged between the first metal member (11) and the second metal member (12), or connected to the pole (2), and the second sealing member (4) is configured to block the electrolyte from flowing between the first metal member (11) and the second metal member (12).

2. The cover plate assembly according to claim 1, wherein: The first sealing member (3) comprises a first extension portion (31) and a second extension portion (32); the first extension portion (31) is sleeved outside the pole (2) and located in the through hole (111); the second extension portion (32) is sleeved outside the first extension portion (31) and connected to the first metal member (11).

3. The cover plate assembly according to claim 2, wherein: The first metal part (11) is provided with a concave platform (112), and the second extension portion (32) is provided in the concave platform (112).

4. The cover plate assembly according to claim 1, wherein: A first connection structure (5) is provided between the first sealing member (3) and the pole (2).

5. The cover plate assembly according to claim 4, wherein: The first connection structure (5) comprises a first groove (51) and a first protrusion (52), one of the first groove (51) and the first protrusion (52) being arranged on the hole wall surface of the through hole (111), and the other being arranged on the outer peripheral surface of the pole (2), wherein the first protrusion (52) is snap-fitted into the first groove (51).

6. The cover plate assembly according to claim 1, wherein: A second connecting structure (6) is provided between the first sealing member (3) and the first metal member (11).

7. The cover plate assembly according to claim 6, wherein: The second connection structure (6) includes a second groove (61) and a second protrusion (62), one of the second groove (61) and the second protrusion (62) is arranged on the outer peripheral surface of the first sealing member (3), and the other is arranged on the inner peripheral surface of the first metal member (11), wherein the second protrusion (62) is snap-fitted into the second groove (61).

8. The cover plate assembly according to any one of claims 1 to 7, characterized in that: The first metal part (11) includes a first main body part (113) and a first connecting part (114) connected to the outer periphery of the first main body part (113); the second metal part (12) includes a second main body part (121) and a second connecting part (122) connected to the inner periphery of the second main body part (121); wherein the first connecting part (114) and the second connecting part (122) are overlapped.

9. The cover plate assembly according to claim 8, wherein: The second sealing member (4) is arranged between the first main body portion (113) and the second connecting portion (122).

10. The cover plate assembly according to claim 9, wherein: The first body portion (113) has a first surface configured to face the electrode assembly, the second connection portion (122) has a second surface configured to face the electrode assembly, and the second seal (4) has a third surface configured to face the electrode assembly, wherein the second surface is located between the first surface and the second surface.

11. The cover plate assembly according to claim 10, wherein: The second sealing member (4) further has a fourth surface facing away from the electrode assembly, and the fourth surface abuts against the first connecting portion (114).

12. The cover plate assembly according to claim 8, wherein: A welding layer (13) is provided between the first connecting portion (114) and the second connecting portion (122).

13. The cover plate assembly according to claim 12, wherein: A heating groove (14) is provided on a surface of one of the first connecting portion (114) and the second connecting portion (122) facing away from the other, and the heating groove (14) extends along the circumference of the cover plate (1), wherein the welding layer (13) corresponds to the heating groove (14).

14. The cover plate assembly according to claim 12, wherein: Along the radial direction of the cover plate (1), a first gap (15) is formed between the first connecting portion (114) and the second main body portion (121); and / or a second gap (16) is formed between the second connecting portion (122) and the first main body portion (113).

15. The cover plate assembly according to claim 8, wherein: The first connecting portion (114) and the second connecting portion (122) are riveted.

16. The cover plate assembly according to any one of claims 1 to 7, characterized in that: The cover plate assembly further comprises: An insulating member (17) is sleeved on the pole (2), and the insulating member (17) is connected to the first metal member (11) and the second metal member (12) on a side facing the electrode assembly.

17. The cover plate assembly according to claim 16, wherein: The second sealing member (4) is provided between the insulating member (17) and the first metal member (11); and / or the second sealing member (4) is provided between the insulating member (17) and the first sealing member (3).

18. The cover plate assembly according to claim 17, wherein: The second sealing member (4) is arranged between the inner circumference of the insulating member (17) and the outer circumference of the pole (2); and / or the second sealing member (4) is arranged on the side of the insulating member (17) facing the electrode assembly, and the second sealing member (4) is arranged around the pole (2).

19. The cover plate assembly according to claim 16, wherein: The cover plate assembly further comprises: A current collecting member (18) is welded to a side of the pole (2) facing the electrode assembly.

20. The cover plate assembly according to claim 19, wherein: A connecting layer (23) is provided on a side of the pole (2) facing the electrode assembly, and the connecting layer (23) is welded to the current collector (18), wherein the pole (2) is made of a first metal material, the current collector (18) and the connecting layer (23) are both made of a second metal material, and the first metal material and the second metal material are different.

21. The cover plate assembly according to claim 19, wherein: A protective layer (181) is provided on the side of the current collecting piece (18) facing away from the pole (2), and the protective layer (181) covers the welding area between the current collecting piece (18) and the pole (2).

22. The cover plate assembly according to any one of claims 1 to 7, characterized in that: The second metal member (12) is configured with a reinforcing rib (124) protruding in a direction away from the electrode assembly.

23. The cover plate assembly according to claim 22, wherein: The reinforcing rib (124) arches in a direction away from the electrode assembly to form a gas storage tank (125).

24. The cover plate assembly according to any one of claims 1 to 7, characterized in that: The first sealing member (3) is a rigid sealing member, and the second sealing member (4) is a flexible sealing member or a sealing rubber layer.

25. A battery pack, characterized in that: The invention comprises the cover plate assembly according to any one of claims 1 to 24.

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