Battery cover plate structure and lithium battery

Abstract

The invention relates to the technical field of lithium batteries, and discloses a battery cover plate structure and a lithium battery, and the battery cover plate structure comprises a plate sheet which is provided with a first through hole along the thickness direction; the connecting block is arranged on one side of the plate sheet in the thickness direction; one axial end of the pole is suitable for penetrating through the first through hole and is riveted with the connecting block; the upper insulating part body is made of an elastic material, and the upper insulating part body is suitable for insulating and sealing between the connecting block and the plate sheet; the upper insulator body extends in the thickness direction towards the direction far away from the connecting block to form a protruding part, the protruding part is arranged between the outer side peripheral wall of the pole and the inner side peripheral wall of the first through hole, and the protruding part is suitable for insulating and sealing between the pole and the plate. According to the battery cover plate structure provided by the invention, insulation sealing between the connecting block and the plate sheet and between the pole and the plate sheet can be simultaneously realized, a sealing ring is omitted, the number of structural parts of the cover plate is reduced, the assembly process and equipment tooling of the cover plate can be simplified, and meanwhile, the production takt is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and particularly relates to a battery cover structure and a lithium battery. Background Art

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries, as power batteries, are widely used in electric vehicles and energy storage fields, and the requirements for the use performance and safety of lithium-ion batteries are increasing day by day. As a component in a lithium battery, the battery cover first plays a role in isolating the internal and external environments through welding with an aluminum shell to achieve a sealing effect; secondly, it connects the internal and external circuits to conduct the current inside the battery to the outside through the cover pole column, playing a role in current conduction.

[0003] Traditional covers are generally mainly composed of a light aluminum sheet, (positive and negative) pole columns, (positive and negative) upper plastics, a lower insulating part, an explosion-proof valve, and an explosion-proof valve protective film. During assembly, the upper plastic, light aluminum sheet, lower insulating part, and sealing ring are sandwiched between the pole column bottom plate and the connecting block. After clamping, the upper end of the pole column and the connecting block are fixed by riveting and laser welding.

[0004] However, the existing cover has a large number of structural parts, resulting in numerous assembly processes for the cover, relatively complex equipment tooling, and a slow production beat. Summary of the Invention

[0005] In view of this, the present invention provides a battery cover structure and a lithium battery to solve the problems that the existing cover has a large number of structural parts, resulting in numerous assembly processes for the cover, relatively complex equipment tooling, and a slow production beat.

[0006] In a first aspect, the present invention provides a battery cover structure, including:

[0007] A plate, which is formed with a first through hole along its thickness direction;

[0008] A connecting block, disposed on one side of the plate in the thickness direction;

[0009] A pole column, disposed on the side of the plate away from the connecting block in the thickness direction, and one end of the pole column along its own axial direction is adapted to pass through the first through hole and be fixedly connected to the connecting block;

[0010] An upper insulating part body, made of an elastic material, and the upper insulating part body is disposed between the connecting block and the plate, and the upper insulating part body is adapted to insulate and seal between the connecting block and the plate;

[0011] The upper insulating part body extends in the thickness direction away from the connecting block to form a protruding part, and the protruding part is disposed between the outer peripheral wall of the pole column and the inner peripheral wall of the first through hole, and the protruding part is adapted to insulate and seal between the pole column and the plate;

[0012] One end of the terminal post away from the connection block along its own axial direction is provided with a bottom plate; the upper insulating part body further includes a sealing part connected to the end of the protruding part, and the sealing part is compressed and sealed between the plate piece and the bottom plate. In the cross-section along the axis of the terminal post, the uncompressed sealing part is in a circular structure.

[0013] For the battery cover structure provided by the present invention, by arranging the upper insulating part body between the connection block and the plate piece, and the upper insulating part body is made of an elastic material. During the process of riveting and laser welding the terminal post and the connection block for fixation, the upper insulating part body is simultaneously extruded by the connection block and the plate piece, so that the upper insulating part body is tightly attached to both the connection block and the plate piece under the action of its own elastic restoring force. It can not only insulate the connection block and the plate piece, but also achieve the sealing between the connection block and the plate piece; by arranging a protruding part on one side in the thickness direction of the upper insulating part body, and the protruding part is placed between the outer peripheral wall of the terminal post and the inner peripheral wall of the first through hole, thereby insulating between the terminal post and the plate piece; furthermore, the insulation between the connection block and the plate piece and between the terminal post and the plate piece is achieved simultaneously, and at the same time, the internal sealing of the battery can be ensured; for the battery cover structure provided by the present invention, the additional sealing ring is omitted, the number of structural parts of the cover is reduced, which is beneficial to simplifying the assembly process and equipment tooling of the cover, and improving the production beat at the same time.

[0014] In an optional embodiment, in the cross-section along the axis of the terminal post, along the axial direction of the terminal post, the minimum distance between the uncompressed sealing part and the plate piece is g1, satisfying 0.2mm ≤ g1 ≤ 1mm; and / or,

[0015] In the cross-section along the axis of the terminal post, along the direction perpendicular to the axis of the terminal post, the distance between the center of the uncompressed sealing part and the hole wall of the first through hole is z, satisfying 0.2mm ≤ z ≤ 3mm; and / or,

[0016] In the cross-section along the axis of the terminal post, along the direction perpendicular to the axis of the terminal post, the distance between the side of the uncompressed sealing part away from the terminal post and the hole wall of the first through hole is w3, satisfying 0.5mm ≤ w3 ≤ 3mm; and / or,

[0017] In the cross-section along the axis of the terminal post, the width of the connection part between the sealing part and the protruding part is w1, satisfying 0.3mm ≤ w1 ≤ 3mm; and / or,

[0018] In the cross-section along the axis of the terminal post, along the direction perpendicular to the axis of the terminal post, the distance between the protruding part and the terminal post is g2, satisfying 0.05mm ≤ g2 ≤ 0.5mm; and / or,

[0019] In the cross-section along the axis of the terminal post, the diameter of the uncompressed sealing part is k, satisfying 0.75mm ≤ k ≤ 4mm.

[0020] In an alternative embodiment, a first counterbore is provided on one side of the upper insulating part body close to the connecting block in the thickness direction, and a first boss mating with the first counterbore is provided on the connecting block. The first boss is adapted to be extrusion-sealed with the first counterbore.

[0021] By setting it in this way, during the process of riveting and laser-welding the pole column and the connecting block for fixation, the connecting block and the plate simultaneously extrude the upper insulating part body, so that after the first boss compresses the upper insulating part body, the extruded material is filled into the peripheral gap of the first counterbore. Under the action of its own elastic restoring force, the upper insulating part body can ensure stable compression sealing between the first counterbore and the first boss, thereby realizing insulating sealing between the connecting block and the plate.

[0022] In an alternative embodiment, the compression amount of the first boss on the first counterbore is B 1 , B 1 satisfies 25% ≤ B 1 / A 1 ≤ 50%, where A 1 is the initial thickness of the first counterbore, and A 1 satisfies A 1 ≥ 0.3 mm.

[0023] By setting it in this way, the effective compression amount is ensured, which can not only ensure the effective rebound of the first counterbore and avoid the collapse of the first counterbore, but also ensure effective pressing between the first counterbore and the first boss to avoid air leakage, thereby effectively preventing seal failure.

[0024] In an alternative embodiment, the depth of the first counterbore is C 1 , the width of the first counterbore is E 1 , C 1 and E 1 satisfy (E 1 − D 1 )·C 1 ≥ D 1 ·B 1 , where D 1 is the width of the first boss, and D 1 ≥ 0.5 mm.

[0025] By setting it in this way, it is ensured that the filling rate of the extruded material filled into the peripheral gap after the first boss compresses the upper insulating part body does not exceed 100%, so as to effectively avoid the first counterbore from expanding due to excessive extrusion filling while realizing the mating compression sealing between the upper insulating part body and the connecting block, thereby ensuring effective sealing between the upper insulating part body and the connecting block.

[0026] In an alternative embodiment, a second sunk platform is provided on one side of the upper insulating part body close to the plate in the thickness direction, and a second convex platform is provided on the plate and is adapted to be extrusion-sealed with the second sunk platform.

[0027] By setting it in this way, during the process of riveting and laser-welding and fixing the pole column and the connection block, the upper insulating part body is extruded by the connection block and the plate at the same time, so that the second convex platform compresses the upper insulating part body and then extrudes and fills the surrounding gaps of the second sunk platform with material. Under the action of its own elastic restoring force, the upper insulating part body can ensure stable compression sealing between the second convex platform and the second sunk platform, and further ensure insulating sealing between the connection block and the plate.

[0028] In an alternative embodiment, the compression amount of the second convex platform on the second sunk platform is B 2 , B 2 satisfies 25% ≤ B 2 / A 2 ≤ 50%, where A 2 is the initial thickness of the second sunk platform, and A 2 satisfies A 2 ≥ 0.3 mm; and / or,

[0029] The radial distance between the second sunk platform and the first sunk platform is F, and F satisfies 1 mm ≤ F ≤ 5 mm.

[0030] By setting it in this way, the effective compression amount is ensured. It can not only ensure the effective resilience of the second sunk platform and avoid the collapse of the second sunk platform, but also ensure effective pressing between the second sunk platform and the second convex platform to avoid air leakage, and further effectively prevent seal failure;

[0031] By setting it in this way, it can not only avoid structural conflicts between the sealing structure of the connection block and the upper insulating part body and the sealing structure of the plate and the upper insulating part body, prevent the upper insulating part body from being damaged due to excessive stress, but also avoid warping in the area of the connection block far from the central axis of the pole column, and ensure the insulating sealing effect between the connection block and the plate by the upper insulating part body.

[0032] In an alternative embodiment, the depth of the second sunk platform is C 2 , the width of the second sunk platform is E 2 , C 2 and E 2 satisfy (E 2 -D 2 )·C 2 ≥ D 2 ·B 2 , where D 2 is the width of the second convex platform.

[0033] By setting it like this, it is ensured that the filling rate of the second boss squeezing the material into the surrounding gaps after compressing the upper insulating part body does not exceed 100%, so as to effectively avoid the second sunk platform from expanding due to excessive material filling during the compression and sealing of the upper insulating part body and the plate, while realizing the compression and sealing of the upper insulating part body and the plate, and further ensuring the effective sealing between the upper insulating part body and the plate.

[0034] In an optional embodiment, the battery cover plate structure further includes a lower insulating part, one side in the thickness direction of the lower insulating part abuts against the bottom plate, and the other side abuts against the plate;

[0035] A second through hole is formed by opening the lower insulating part in the thickness direction; the protruding part extends in the thickness direction away from the connecting block into the second through hole, and the protruding part is arranged between the outer peripheral wall of the pole column and the inner peripheral wall of the second through hole;

[0036] In the cross-section along the axis of the pole column, along the axis direction of the pole column, the thickness of the lower plastic between the bottom plate and the plate is h, satisfying 0.6mm ≤ h ≤ 2mm, and the compression rate of the sealing part satisfies 20% ≤ (k - h) / h ≤ 50%; and / or, in the cross-section along the axis of the pole column, along the direction perpendicular to the axis of the pole column, the distance between the side of the uncompressed sealing part away from the pole column and the hole wall of the second through hole is w2, satisfying w2 ≥ 1.5 × w3.

[0037] By setting it like this, during the riveting and laser welding fixation of the pole column and the connecting block, the outer peripheral wall of the pole column and the inner peripheral wall of the second through hole can exert extrusion force on the protruding part. Through the interaction between the extrusion force and the elastic restoring force of the protruding part itself, the inner and outer sides of the protruding part can be closely attached to the outer peripheral wall of the pole column and the inner peripheral wall of the second through hole at the same time, so as to realize the sealing between the pole column and the lower insulating part, and further ensure the internal sealing of the battery.

[0038] In a second aspect, the present invention also provides a lithium battery, including: a lithium battery body, and the battery cover plate structure as described above.

[0039] Since the lithium battery in the second aspect includes the battery cover plate structure in the first aspect, therefore, the lithium battery in the second aspect includes all the beneficial effects of the battery cover plate structure in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0041] Figure 1Explosion structure schematic diagram of a battery cover plate structure according to an embodiment of the present invention;

[0042] Figure 2 is Figure 1 Partial enlarged schematic diagram of the sheet shown in another perspective;

[0043] Figure 3 is Figure 1 Stereoscopic structure schematic diagram of the upper insulating part body shown in one perspective;

[0044] Figure 4 Top view structure schematic diagram of a battery cover plate structure according to an embodiment of the present invention;

[0045] Figure 5 is Figure 4 Cross-sectional structure schematic diagram of the P-P section shown in;

[0046] Figure 6 is Figure 5 Partial enlarged schematic diagram at Q shown in;

[0047] Figure 7 is Figure 1 Stereoscopic structure schematic diagram of the upper insulating part body shown in another perspective;

[0048] Figure 8 is Figure 1 Stereoscopic structure schematic diagram of the connecting block shown in one perspective;

[0049] Figure 9 is Figure 6 Dimension schematic diagram after partial enlargement at T shown in;

[0050] Figure 10 is Figure 6 Another dimension schematic diagram after partial enlargement at T shown in;

[0051] Figure 11 is Figure 6 Another dimension schematic diagram after partial enlargement at T shown in;

[0052] Figure 12 is Figure 1 Stereoscopic structure schematic diagram of the lower insulating part shown in another perspective;

[0053] Figure 13 Partial enlarged structure schematic diagram of another battery cover plate structure according to an embodiment of the present invention;

[0054] Figure 14 is Figure 13 Structure schematic diagram during the assembly process of the sheet and the upper insulating part body shown in;

[0055] Figure 15For Figure 13 Schematic structural diagram after the assembly of the plate and the upper insulator body shown;

[0056] Figure 16 Schematic structural diagram of the cooperation between the plate and the sealing part when the value of z is too small;

[0057] Figure 17 Schematic structural diagram of the cooperation between the plate and the sealing part of the embodiment of the present invention.

[0058] Explanation of reference numerals:

[0059] 10. Plate; 11. First through hole; 12. Second boss;

[0060] 20. Connecting block; 21. First boss;

[0061] 30. Terminal post; 31. Bottom plate;

[0062] 40. Upper insulator body; 41. Protruding part; 42. First counterbore; 43. Second counterbore; 44. Sealing part;

[0063] 50. Lower insulator; 51. Second through hole. Detailed implementation manners

[0064] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0065] In the related art, the cover plate generally mainly consists of a plate (positive and negative electrodes), terminal posts (positive and negative electrodes), upper plastic, lower insulator, explosion valve and explosion-proof valve protective film. During assembly, the terminal post connecting block clamps the upper plastic and the plate insulator sealing ring. After clamping, the terminal post and the connecting block are riveted and laser welded for fixation. Among them, the upper plastic plays a role of connecting the block and the plate; the sealing ring is to prevent the terminal post and the plate, ensure the internal sealing of the battery, and play an insulating and sealing role.

[0066] However, the number of structural parts of the cover plate in the related art is large, resulting in numerous assembly processes for the cover plate, relatively complex equipment tooling, and a slow production beat.

[0067] The following will describe the embodiments of the present invention in conjunction with Figures 1 to 12 , the embodiments of the present invention will be described.

[0068] According to an embodiment of the present invention, on the one hand, a battery cover plate structure is provided, including:

[0069] The plate 10, which can be made of aluminum material, please refer to Figure 1 and Figure 2 As shown, a first through hole 11 is formed by opening the plate 10 in the thickness direction;

[0070] The connecting block 20 is arranged on one side of the plate 10 in the thickness direction;

[0071] The terminal post 30 is arranged on the side of the plate 10 away from the connecting block 20 in the thickness direction. One end of the terminal post 30 along its own axial direction is adapted to pass through the first through hole 11 and is fixed to the connecting block 20 by riveting and laser welding;

[0072] The upper insulating part body 40, which is made of an elastic material, is arranged between the connecting block 20 and the plate 10. The upper insulating part body 40 is adapted to insulate and seal between the connecting block 20 and the plate 10 during the process of riveting and laser welding the terminal post 30 and the connecting block 20;

[0073] Please refer to Figure 1 and Figure 3 As shown, the upper insulating part body 40 extends in the thickness direction away from the connecting block 20 to form a protruding part 41. The protruding part 41 and the upper insulating part body 40 are of an integrally formed structure. Please also refer to Figure 6 As shown, the protruding part 41 is of an annular boss structure. The protruding part 41 is coaxially arranged with the first through hole 11. The protruding part 41 is arranged between the outer peripheral wall of the terminal post 30 and the inner peripheral wall of the first through hole 11. The protruding part 41 is adapted to insulate between the terminal post 30 and the plate 10.

[0074] It should be noted that the upper insulating part body 40 can be made of rubber materials such as fluororubber, etc., with excellent elastic properties, insulating properties and electrolyte resistance properties, so as to play a role in insulation and also play a role in sealing while playing the role of insulation.

[0075] It should be noted that the protruding part 41, as a part of the upper insulating part body 40, during the process of riveting and laser welding the terminal post 30 and the connecting block 20, the outer peripheral wall of the terminal post 30 and the inner peripheral wall of the first through hole 11 can exert an extrusion force on the protruding part 41. Through the interaction between the extrusion force and the elastic restoring force of the protruding part 41 itself, the inner and outer sides of the protruding part 41 can be tightly attached to the outer peripheral wall of the terminal post 30 and the inner peripheral wall of the first through hole 11 at the same time, so as to realize the sealing between the terminal post 30 and the plate 10.

[0076] The battery cover plate structure provided in this embodiment is configured such that an upper insulating member body 40 is disposed between the connecting block 20 and the plate 10, and the upper insulating member body 40 is made of an elastic material. During the process of riveting and laser welding the pole 30 and the connecting block 20 for fixation, the connecting block 20 and the plate 10 simultaneously extrude the upper insulating member body 40, causing the upper insulating member body 40 to closely adhere to both the connecting block 20 and the plate 10 under the action of its own elastic restoring force. This not only insulates the connecting block 20 from the plate 10 but also achieves sealing between the connecting block 20 and the plate 10. By providing a protruding portion 41 on one side of the upper insulating member body 40 in the thickness direction, with the protruding portion 41 disposed between the outer peripheral wall of the pole 30 and the inner peripheral wall of the first through hole 11, insulation between the pole 30 and the plate 10 is achieved. Thus, insulation between the connecting block 20 and the plate 10 and between the pole 30 and the plate 10 is simultaneously realized, while ensuring the internal sealing of the battery. The battery cover plate structure provided in this embodiment eliminates the need for an additional sealing ring, reduces the number of structural components of the cover plate, simplifies the assembly process and equipment tooling of the cover plate, and improves the production tempo at the same time.

[0077] In some embodiments, referring to Figure 7 as shown, on the side of the upper insulating member body 40 close to the connecting block 20 in the thickness direction, a first sunk platform 42 is provided. Referring to Figure 8 as shown, on the connecting block 20, a first boss 21 is provided that mates with the first sunk platform 42. Please also refer to Figure 6 and Figure 9 as shown, the first sunk platform 42 and the first boss 21 are coaxially arranged, and the first boss 21 is adapted to be extrusion-sealed with the first sunk platform 42.

[0078] In this embodiment, by providing the first sunk platform 42 on the upper insulating member body 40 and simultaneously providing the first boss 21 on the connecting block 20 that mates with the first sunk platform 42, during the process of riveting and laser welding the pole 30 and the connecting block 20 for fixation, the connecting block 20 and the plate 10 simultaneously extrude the upper insulating member body 40, causing the first boss 21 to compress the upper insulating member body 40 and then extrude and fill the surrounding gaps of the first sunk platform 42 with material. The upper insulating member body 40 can ensure stable compression sealing between the first sunk platform 42 and the first boss 21 under the action of its own elastic restoring force, thereby achieving insulating sealing between the connecting block 20 and the plate 10.

[0079] In some embodiments, referring to Figure 9 as shown, the compression amount of the first boss 21 on the first sunk platform 42 is B 1 , B 1 satisfies 25% ≤ B 1 / A 1 ≤ 50%, where A 1is the initial thickness of the first sinking platform 42, A 1 Satisfy A 1 ≥0.3mm.

[0080] It should be noted that, please refer to Figure 9 As shown, the dimension line A 1 marks the initial thickness of the first sinking platform 42; if the initial thickness of the first sinking platform 42 is too thin, it is not only easy to cause the elastic force of the first sinking platform 42 to be too small, resulting in inability to rebound or insufficient rebound, leading to seal failure, but also easy to cause the first sinking platform 42 to collapse during the process of the connecting block 20 and the plate 10 simultaneously squeezing the upper insulating part body 40, which will also lead to seal failure. Therefore, the initial thickness A of the first sinking platform 42 1 needs to satisfy A 1 ≥0.3mm. Still refer to Figure 9 As shown, the dimension line B 1 marks the compression amount of the first convex platform 21 on the first sinking platform 42; if the compression amount of the first convex platform 21 on the first sinking platform 42 is too large, it is easy to cause the first sinking platform 42 to be permanently deformed and unable to rebound, and even cause the first sinking platform 42 to collapse, resulting in seal failure. Therefore, the compression amount B of the first convex platform 21 on the first sinking platform 42 1 needs to satisfy B 1 / A 1 ≤50%; if the compression amount of the first convex platform 21 on the first sinking platform 42 is too small, it is difficult to effectively compress between the first sinking platform 42 and the first convex platform 21, and it is easy to leak air. Therefore, the compression amount B of the first convex platform 21 on the first sinking platform 42 1 also needs to satisfy B 1 / A 1 ≥25%.

[0081] In this embodiment, the compression amount B of the first convex platform 21 on the first sinking platform 42 1 by satisfying 25% ≤ B 1 / A 1 ≤50%, where A 1 is the initial thickness of the first sinking platform 42, A 1 satisfies A 1 ≥0.3mm, so as to ensure the effective compression amount, which can not only ensure the effective rebound of the first sinking platform 42 and avoid the collapse of the first sinking platform 42, but also ensure the effective compression between the first sinking platform 42 and the first convex platform 21 and avoid air leakage, thereby effectively preventing seal failure.

[0082] In some embodiments, please refer to Figure 10 As shown, the depth of the first sinking platform 42 is C 1 , the width of the first sinking platform 42 is E 1 , C 1 and E 1 satisfy (E1 -D 1 )·C 1 ≥D 1 ·B 1 , where D 1 is the width of the first boss 21, and D 1 ≥0.5 mm.

[0083] It should be noted that the width D of the first boss 21 1 is the effective compression sealing width. If the effective compression sealing width is too small, it is likely to cause sealing failure. Therefore, D 1 should satisfy D 1 ≥0.5 mm; please also combine with Figure 9 and Figure 10 as shown, "D 1 ·B 1 " represents the volume of the material extruded by the first boss 21 when compressing the upper insulating part body 40, and "(E 1 -D 1 )·C 1 " represents the volume of the filling gap between the first boss 21 and the first sunk platform 42; by satisfying (E 1 -D 1 )·C 1 ≥D 1 ·B 1 , it is ensured that the filling rate of the material extruded by the first boss 21 when compressing the upper insulating part body 40 into the surrounding gaps does not exceed 100%, so as to effectively avoid the first sunk platform 42 from expanding due to excessive material filling during the compression matching seal between the upper insulating part body 40 and the connecting block 20, and further ensure the effective seal between the upper insulating part body 40 and the connecting block 20.

[0084] Combined with Table 1 below, through several test examples, the helium leak detection effect of the battery cover structure provided by the embodiment of the present invention for sealing through the first boss 21 and the first sunk platform 42 is verified.

[0085] Under normal conditions:

[0086] As shown in Example 9 of Table 1, A 1 =0.33 mm, B 1 =0.16 mm, C 1 =0.4 mm, D 1 =0.7 mm, E 1 =1.3 mm. At this time, the dimensions satisfy A 1 ≥0.3 mm, satisfy 25%≤B 1 / A 1 ≤50%, satisfy D 1 ≥0.5 mm, satisfy (E 1 -D1 )·C 1 ≥D 1 ·B 1 , the helium leak detection of the battery cover plate structure passes and meets the requirements;

[0087] As shown in Example 10 of Table 1, A 1 = 0.8 mm, B 1 = 0.3 mm, C 1 = 0.3 mm, D 1 = 0.63 mm, E 1 = 1.3 mm. At this time, the dimensions meet A 1 ≥ 0.3 mm, meet 25% ≤ B 1 / A 1 ≤ 50%, meet D 1 ≥ 0.5 mm, meet (E 1 -D 1 )·C 1 ≥D 1 ·B 1 , the helium leak detection of the battery cover plate structure passes and meets the requirements;

[0088] As shown in Example 11 of Table 1, A 1 = 0.31 mm, B 1 = 0.08 mm, C 1 = 0.33 mm, D 1 = 0.77 mm, E 1 = 1.5 mm. At this time, the dimensions meet A 1 ≥ 0.3 mm, meet 25% ≤ B 1 / A 1 ≤ 50%, meet D 1 ≥ 0.5 mm, meet (E 1 -D 1 )·C 1 ≥D 1 ·B 1 , the helium leak detection of the battery cover plate structure passes and meets the requirements.

[0089] In the extreme state:

[0090] As shown in Example 1 of Table 1, A 1 = 0.32 mm, B 1 = 0.16 mm, C 1 = 0.5 mm, D 1 = 0.7 mm, E 1 = 1.4 mm. When A 1 is close to 0.3 mm, B 1 / A 1 = 50%, and the remaining dimensions meet D 1 ≥ 0.5 mm, meet (E1 -D 1 )·C 1 ≥D 1 ·B 1 When this occurs, the helium leak detection of the battery cover structure passes and meets the requirements;

[0091] As shown in Example 4 of Table 1, A 1 = 0.7 mm, B 1 = 0.18 mm, C 1 = 0.5 mm, D 1 = 0.51 mm, E 1 = 1.4 mm. When D 1 is close to 0.5 mm, B 1 / A 1 = 26%, and the remaining dimensions meet A 1 ≥ 0.3 mm, meet (E 1 -D 1 )·C 1 ≥D 1 ·B 1 When this occurs, the helium leak detection of the battery cover structure passes and meets the requirements;

[0092] As shown in Example 8 of Table 1, A 1 = 0.34 mm, B 1 = 0.15 mm, C 1 = 0.3 mm, D 1 = 0.7 mm, E 1 = 1.1 mm. When (E 1 -D 1 )·C 1 is slightly greater than D 1 ·B 1 , and the remaining dimensions meet A 1 ≥ 0.3 mm, meet 25% ≤ B 1 / A 1 ≤ 50%, meet D 1 ≥ 0.5 mm, the helium leak detection of the battery cover structure passes and meets the requirements.

[0093] The following are comparative examples:

[0094] As shown in Comparative Example 2 of Table 1, when A 1 = 0.28 mm, it does not meet A 1 ≥ 0.3 mm, and the remaining dimensions meet D 1 ≥ 0.5 mm, meet 25% ≤ B 1 / A 1 ≤ 50%, meet (E 1 -D 1 )·C 1 ≥D 1 ·B1 When the helium leak detection rate of the battery cover plate structure does not meet the requirements;

[0095] As shown in Comparative Example 3 of Table 1, when D 1 = 0.47 mm, it does not meet D 1 ≥ 0.5 mm, and the remaining dimensions meet A 1 ≥ 0.3 mm, meet 25% ≤ B 1 / A 1 ≤ 50%, meet (E 1 -D 1 )·C 1 ≥ D 1 ·B 1 When, the helium leak detection rate of the battery cover plate structure does not meet the requirements;

[0096] As shown in Comparative Example 5 of Table 1, when B 1 / A 1 = 24%, it does not meet 25% ≤ B 1 / A 1 ≤ 50%, and the remaining dimensions meet A 1 ≥ 0.3 mm, meet D 1 ≥ 0.5 mm, meet (E 1 -D 1 )·C 1 ≥ D 1 ·B 1 When, the helium leak detection rate of the battery cover plate structure does not meet the requirements;

[0097] As shown in Comparative Example 6 of Table 1, when B 1 / A 1 = 53%, it does not meet 25% ≤ B 1 / A 1 ≤ 50%, and the remaining dimensions meet A 1 ≥ 0.3 mm, meet D 1 ≥ 0.5 mm, meet (E 1 -D 1 )·C 1 ≥ D 1 ·B 1 When, the helium leak detection rate of the battery cover plate structure does not meet the requirements;

[0098] As shown in Comparative Example 7 of Table 1, when (E 1 -D 1 )·C 1 ≥ D 1 ·B 1 is not met, and the remaining dimensions meet A 1 ≥ 0.3 mm, meet D 1 ≥ 0.5 mm, meet 25% ≤ B 1 / A 1When it is ≤ 50%, the helium leak detection rate of the battery cover plate structure does not meet the requirements.

[0099] Table 1

[0100]

[0101] Thus, first of all, the initial thickness A of the first sinking platform 42 1 satisfies A 1 ≥ 0.3 mm, which can effectively prevent the sealing failure of the battery cover plate structure; secondly, the width D of the first convex platform 21 1 satisfies D 1 ≥ 0.5 mm, which can effectively prevent the sealing failure of the battery cover plate structure; thirdly, B 1 / A 1 satisfies 25% ≤ B 1 / A 1 ≤ 50%, which can ensure the effective sealing of the battery cover plate structure; fourthly, by satisfying (E 1 -D 1 )·C 1 ≥ D 1 ·B 1 , the effective sealing of the battery cover plate structure can be ensured.

[0102] In some embodiments, please refer to Figure 3 shown, a second sinking platform 43 is provided on one side of the upper insulating part body 40 close to the plate 10 in the thickness direction. Please refer to Figure 2 shown, a second convex platform 12 paired with the second sinking platform 43 is provided on the plate 10. Please combine Figure 6 and Figure 9 shown, the second sinking platform 43 and the second convex platform 12 are both coaxially arranged with the protruding part 41, and the second convex platform 12 is suitable for extrusion sealing with the second sinking platform 43.

[0103] In this embodiment, by providing the second sinking platform 43 on the upper insulating part body 40 and at the same time providing the second convex platform 12 paired with the second sinking platform 43 on the plate 10, during the process of riveting and laser welding the pole 30 and the connecting block 20 for fixation, the connecting block 20 and the plate 10 simultaneously extrude the upper insulating part body 40, so that the second convex platform 12 compresses the upper insulating part body 40 and then extrudes and fills the surrounding gaps of the second sinking platform 43 with materials. The upper insulating part body 40 can ensure stable compression sealing between the second convex platform 12 and the second sinking platform 43 under the action of its own elastic restoring force, and further ensure the insulating seal between the connecting block 20 and the plate 10.

[0104] In some embodiments, please refer to Figure 9 shown, the compression amount of the second convex platform 12 on the second sinking platform 43 is B 2 , B 2Satisfy 25% ≤ B 2 / A 2 ≤ 50%, where A 2 is the initial thickness of the second sinking platform 43, and A 2 satisfies A 2 ≥ 0.3 mm.

[0105] It should be noted that, please refer to Figure 9 as shown, the dimension line A 2 marks the initial thickness of the second sinking platform 43; if the initial thickness of the second sinking platform 43 is too thin, it is not only easy to cause the elastic force of the second sinking platform 43 to be too small, resulting in inability to rebound or insufficient rebound, leading to sealing failure, but also easy to cause the second sinking platform 43 to collapse during the process of the connecting block 20 and the plate 10 simultaneously squeezing the upper insulating part body 40, which will also lead to sealing failure. Therefore, the initial thickness A 2 of the second sinking platform 43 needs to satisfy A 2 ≥ 0.3 mm. Still refer to Figure 9 as shown, the dimension line B 2 marks the compression amount of the second convex platform 12 on the second sinking platform 43; if the compression amount of the second convex platform 12 on the second sinking platform 43 is too large, it is easy to cause the second sinking platform 43 to be permanently deformed and unable to rebound, and even cause the second sinking platform 43 to collapse, resulting in sealing failure. Therefore, the compression amount B 2 of the second convex platform 12 on the second sinking platform 43 needs to satisfy B 1 / A 1 ≤ 50%; if the compression amount of the second convex platform 12 on the second sinking platform 43 is too small, it is difficult to effectively press the second sinking platform 43 and the second convex platform 12 together, and it is easy to leak air. Therefore, the compression amount B 2 of the second convex platform 12 on the second sinking platform 43 also needs to satisfy B 1 / A 1 ≥ 25%.

[0106] In this embodiment, the compression amount B 2 of the second convex platform 12 on the second sinking platform 43 is ensured by satisfying 25% ≤ B 2 / A 2 ≤ 50%, where A 2 is the initial thickness of the second sinking platform 43, and A 2 satisfies A 2 ≥ 0.3 mm, so as to ensure the effective compression amount, which can not only ensure the effective rebound of the second sinking platform 43 and avoid the collapse of the second sinking platform 43, but also ensure the effective pressing between the second sinking platform 43 and the second convex platform 12 and avoid air leakage, thereby effectively preventing sealing failure.

[0107] In some embodiments, please refer to Figure 11 as shown, the depth of the second sinking platform 43 is C 2, the width of the second sinking platform 43 is E 2 , C 2 and E 2 satisfy (E 2 −D 2 )·C 2 ≥D 2 ·B 2 , where D 2 is the width of the second convex platform 12

[0108] Furthermore, D 2 ≥0.5 mm

[0109] It should be noted that the width D 2 of the second convex platform 12 is the effective compression sealing width. If the effective compression sealing width is too small, it is easy to cause sealing failure. Therefore, D 2 needs to satisfy D 2 ≥0.5 mm; please also combine Figure 9 and Figure 11 as shown, "D 2 ·B 2 " represents the volume of the material extruded by the second convex platform 12 on the upper insulating part body 40, and "(E 2 −D 2 )·C 2 " represents the volume of the filling gap between the second convex platform 12 and the second sinking platform 43; by satisfying (E 2 −D 2 )·C 2 ≥D 2 ·B 2 , it is ensured that the filling rate of the material extruded by the second convex platform 12 on the upper insulating part body 40 into the surrounding gaps does not exceed 100%, so as to effectively avoid the second sinking platform 43 from expanding due to excessive material filling during the compression of the upper insulating part body 40 and the plate 10, and further ensure the effective sealing between the upper insulating part body 40 and the plate 10

[0110] Combined with Table 2 below, through several groups of test examples, the helium leak detection effect of the battery cover structure provided by the embodiment of the present invention sealed by the second convex platform 12 and the second sinking platform 43 is verified

[0111] Under normal conditions:

[0112] As shown in Example 9 of Table 2, A 2 =0.33 mm, B 2 =0.16 mm, C 2 =0.4 mm, D 2 =0.7 mm, E 2 =1.3 mm. At this time, the dimensions satisfy A 2≥0.3 mm, satisfying 25% ≤ B 2 / A 2 ≤50%, satisfying D 2 ≥0.5 mm, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 , the helium leak detection of the battery cover structure passes and meets the requirements;

[0113] As shown in Example 10 of Table 2, A 2 = 0.8 mm, B 2 = 0.3 mm, C 2 = 0.3 mm, D 2 = 0.63 mm, E 2 = 1.3 mm, at this time the dimensions satisfy A 2 ≥0.3 mm, satisfying 25% ≤ B 2 / A 2 ≤50%, satisfying D 2 ≥0.5 mm, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 , the helium leak detection of the battery cover structure passes and meets the requirements;

[0114] As shown in Example 11 of Table 2, A 2 = 0.31 mm, B 2 = 0.08 mm, C 2 = 0.33 mm, D 2 = 0.77 mm, E 2 = 1.5 mm, at this time the dimensions satisfy A 2 ≥0.3 mm, satisfying 25% ≤ B 2 / A 2 ≤50%, satisfying D 2 ≥0.5 mm, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 , the helium leak detection of the battery cover structure passes and meets the requirements.

[0115] In the extreme state:

[0116] As shown in Example 1 of Table 2, A 2 = 0.32 mm, B 2 = 0.16 mm, C 2 = 0.5 mm, D 2 = 0.7 mm, E 2 = 1.4 mm, when A2 Close to 0.3 mm, B 2 / A 2 = 50%, and the remaining dimensions satisfy D 2 ≥ 0.5 mm, satisfy (E 2 -D 2 )·C 2 ≥ D 2 ·B 2 When this is the case, the helium leak detection of the battery cover structure passes and meets the requirements;

[0117] As shown in Example 4 of Table 2, A 2 = 0.7 mm, B 2 = 0.18 mm, C 2 = 0.5 mm, D 2 = 0.51 mm, E 2 = 1.4 mm, when D 2 is close to 0.5 mm, B 2 / A 2 = 26%, and the remaining dimensions satisfy A 2 ≥ 0.3 mm, satisfy (E 2 -D 2 )·C 2 ≥ D 2 ·B 2 When this is the case, the helium leak detection of the battery cover structure passes and meets the requirements;

[0118] As shown in Example 8 of Table 2, A 2 = 0.34 mm, B 2 = 0.15 mm, C 2 = 0.3 mm, D 2 = 0.7 mm, E 2 = 1.1 mm, when (E 2 -D 2 )·C 2 is slightly larger than D 2 ·B 2 , and the remaining dimensions satisfy A 2 ≥ 0.3 mm, satisfy 25% ≤ B 2 / A 2 ≤ 50%, satisfy D 2 ≥ 0.5 mm, the helium leak detection of the battery cover structure passes and meets the requirements.

[0119] The following are comparative examples:

[0120] As shown in Comparative Example 2 of Table 2, when A 2 = 0.28 mm, it does not satisfy A 2 ≥ 0.3 mm, and the remaining dimensions satisfy D 2 ≥ 0.5 mm, satisfy 25% ≤ B 2 / A2 ≤50%, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 when, the helium leak detection rate of the battery cover structure does not meet the requirements;

[0121] As shown in Comparative Example 3 of Table 2, when D 2 = 0.47 mm, not satisfying D 2 ≥0.5 mm, and the remaining dimensions satisfying A 2 ≥0.3 mm, satisfying 25% ≤ B 2 / A 2 ≤50%, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 when, the helium leak detection rate of the battery cover structure does not meet the requirements;

[0122] As shown in Comparative Example 5 of Table 2, when B 2 / A 2 = 24%, not satisfying 25% ≤ B 2 / A 2 ≤50%, and the remaining dimensions satisfying A 2 ≥0.3 mm, satisfying D 2 ≥0.5 mm, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 when, the helium leak detection rate of the battery cover structure does not meet the requirements;

[0123] As shown in Comparative Example 6 of Table 2, when B 2 / A 2 = 53%, not satisfying 25% ≤ B 2 / A 2 ≤50%, and the remaining dimensions satisfying A 2 ≥0.3 mm, satisfying D 2 ≥0.5 mm, satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 when, the helium leak detection rate of the battery cover structure does not meet the requirements;

[0124] As shown in Comparative Example 7 of Table 2, when not satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2, and the remaining dimensions satisfy A 2 ≥0.3 mm, satisfy D 2 ≥0.5 mm, satisfy 25% ≤ B 2 / A 2 ≤50%, the helium leak detection rate of the battery cover structure does not meet the requirements.

[0125] Table 2

[0126]

[0127]

[0128] Thus, first of all, the initial thickness A of the second sink 43 2 satisfies A 2 ≥0.3 mm, which can effectively prevent the sealing failure of the battery cover structure; secondly, the width D of the second boss 12 2 satisfies D 2 ≥0.5 mm, which can effectively prevent the sealing failure of the battery cover structure; thirdly, B 2 / A 2 satisfies 25% ≤ B 2 / A 2 ≤50%, which can ensure the effective sealing of the battery cover structure; fourthly, by satisfying (E 2 -D 2 )·C 2 ≥D 2 ·B 2 , the effective sealing of the battery cover structure can be ensured.

[0129] In some embodiments, please refer to Figure 9 shown, the radial distance between the second sink 43 and the first sink 42 is F, and F satisfies 1 mm ≤ F ≤ 5 mm.

[0130] It should be noted that, please refer to Figure 9 shown, the dimension line F indicates the radial distance between the second sink 43 and the first sink 42; the radial distance between the second sink 43 and the first sink 42 cannot be too small, otherwise it is easy to cause a structural conflict between the sealing structure of the connecting block 20 and the insulating part body 40 and the sealing structure of the plate 10 and the insulating part body 40, resulting in the damage of the upper insulating part body 40 due to excessive stress. Therefore, the radial distance F between the second sink 43 and the first sink 42 needs to satisfy F ≥ 1 mm; please refer to Figure 6As shown, since the mating compression seals between the connecting block 20 and the upper insulator body 40 and between the plate 10 and the upper insulator body 40 are both provided with pressing forces through the riveting laser welding fixation of the pole column 30 and the connecting block 20, if the radial distance between the second sink 43 and the first sink 42 is too large, on the one hand, it is easy to cause warping in the area of the connecting block 20 away from the central axis of the pole column 30, and on the other hand, it is easy to cause the area of the connecting block 20 away from the central axis of the pole column 30 to be unable to press the upper insulator body 40, affecting the sealing effect. Therefore, the radial distance F between the second sink 43 and the first sink 42 also needs to satisfy F ≤ 5 mm.

[0131] In this embodiment, by satisfying 1 mm ≤ F ≤ 5 mm for the radial distance F between the second sink 43 and the first sink 42, it is possible to avoid structural conflicts between the sealing structure of the connecting block 20 mating with the upper insulator body 40 and the sealing structure of the plate 10 mating with the upper insulator body 40, prevent the upper insulator body 40 from being damaged due to excessive stress, and avoid warping in the area of the connecting block 20 away from the central axis of the pole column 30, ensuring the insulating sealing effect between the upper insulator body 40 for the connecting block 20 and the plate 10.

[0132] In some embodiments, please refer to Figure 6 As shown, a bottom plate 31 is provided at one end of the pole column 30 along its own axial direction away from the connecting block 20; the battery cover structure further includes a lower insulator 50, and the lower insulator 50 is disposed between the bottom plate 31 and the plate 10. One side in the thickness direction of the lower insulator 50 abuts against the bottom plate 31, and the other side abuts against the plate 10;

[0133] Please also refer to Figure 12 As shown, a second through hole 51 is formed by opening the lower insulator 50 in the thickness direction; still referring to Figure 6 As shown, the protruding portion 41 extends in the thickness direction away from the connecting block 20 into the second through hole 51, and the protruding portion 41 is disposed between the outer peripheral wall of the pole column 30 and the inner peripheral wall of the second through hole 51.

[0134] It should be noted that, as a part of the upper insulator body 40, during the process of riveting laser welding fixation of the pole column 30 and the connecting block 20, the outer peripheral wall of the pole column 30 and the inner peripheral wall of the second through hole 51 can exert extrusion forces on the protruding portion 41. Through the interaction between the extrusion forces and the elastic restoring force of the protruding portion 41 itself, the inner and outer sides of the protruding portion 41 can be closely attached to the outer peripheral wall of the pole column 30 and the inner peripheral wall of the second through hole 51 at the same time, thereby realizing the seal between the pole column 30 and the lower insulator 50, and further ensuring the internal seal of the battery.

[0135] In one embodiment, as Figure 13As shown, the upper insulating part body 40 further includes a sealing part 44 connected to the end of the protruding part 41. The sealing part 44 is compression-sealed between the plate 10 and the bottom plate 31. In a cross-section along the axis of the pole column 30, the uncompressed sealing part 44 has a circular structure. Therefore, by providing the sealing part 44 to seal between the plate 10 and the bottom plate 31, it is possible to prevent the electrolyte from coming into contact with the pole column 30 and causing corrosion failure of the pole column 30, while ensuring that the upper insulating part body 40 is convenient for assembly.

[0136] It should be noted that for the copper-aluminum composite pole column 30, the bottom plate 31 is made of copper, and the upper part of the bottom plate 31 is made of aluminum. The battery negative electrode is at a low potential. If the electrolyte comes into contact with the aluminum pole column 30, electrochemical corrosion will occur, resulting in the separation of the composite cross-section of the copper and aluminum materials and the failure of the structural strength of the pole column 30.

[0137] It should be further noted that in this embodiment, the upper insulating part body 40, the protruding part 41, and the sealing part 44 are integrally formed. During the assembly process of the battery cover structure in this embodiment, it is necessary to install the integrally formed upper insulating part body 40 into the first through hole 11 of the plate 10. Therefore, in this embodiment, the cross-section of the uncompressed sealing part 44 is circular. During the assembly process, the contact area between the sealing part 44 and the hole wall of the first through hole 11 is small (please refer to Figure 14 ), and the resistance is small, which is more convenient for the assembly of the upper insulating part body 40. Moreover, when the upper insulating part body 40 is assembled in place, the arc-shaped outer wall of the sealing part 44 can play a guiding role, facilitating the deformation and reset of the sealing part 44 during the assembly process, and making the sealing part 44 slide under the plate 10.

[0138] In one embodiment, as Figure 13 shown, in a cross-section along the axis of the pole column 30, along the axis direction of the pole column 30, the minimum distance between the uncompressed sealing part 44 and the plate 10 is g1, satisfying 0.2 mm ≤ g1 ≤ 1 mm. With such a setting, while ensuring that the sealing part 44 can be assembled in place, it is possible to avoid waste of space and ensure the extrusion effect of the bottom plate 31 on the sealing part 44 after assembly.

[0139] It should be noted that if g1 > 1 mm, the distance between the sealing part 44 before compression and the plate 10 is too far, resulting in too much space occupied by the sealing part 44 and the plate 10 after assembly. Moreover, during the subsequent installation process of the pole column 30, it is not convenient for the bottom plate 31 to extrude the sealing part 44, affecting the sealing effect. If g1 < 0.2 mm, the distance between the sealing part 44 before compression and the plate 10 is too close, and it is easy to interfere with the plate 10 during the deformation and reset process of the sealing part 44, making it inconvenient for the sealing part 44 to be in place during the assembly process (from Figure 14 to Figure 15 ).

[0140] In one embodiment, as Figure 13 shown, in the cross-section along the axis of the pole column 30, in the direction perpendicular to the axis of the pole column 30, the distance between the center of the uncompressed sealing portion 44 and the hole wall of the first through hole 11 is z, satisfying 0.2 mm ≤ z ≤ 3 mm. With such a setting, while facilitating the deformation reset during the assembly process of the sealing portion 44, the sealing effect of the sealing portion 44 is ensured.

[0141] It should be noted that if z > 3 mm, the deformation amounts of the protruding portion 41 and the sealing portion 44 during the assembly process are too large (please refer to Figure 14 ), after the assembly is in place, it is not convenient for the deformation reset of the protruding portion 41 and the sealing portion 44, affecting the assembly quality of the upper insulating part body 40. If z < 0.2 mm, when the sealing portion 44 is assembled, the volume between the plate 10 and the bottom plate 31 is too small, and the sealing effect is poor. And, please compare and view Figure 16 and Figure 17 , if the value of z is too small, when the sealing portion 44 is squeezed, it is easy to cause the lower edge of the plate 10 in the first through hole 11 to directly pierce the outer wall of the sealing portion 44, easily causing the sealing portion 44 to be cut, and also affecting the sealing effect of the sealing portion 44; therefore, the value of z is controlled to avoid the value of z being too small. After the sealing portion 44 is squeezed, the lower edge of the plate 10 in the first through hole 11 can be located in the groove area at the connection position of the sealing portion 44 and the protruding portion 41, avoiding damage to the sealing portion 44, thereby ensuring the sealing effect of the sealing portion 44.

[0142] In one embodiment, as Figure 13 shown, in the cross-section along the axis of the pole column 30, in the direction perpendicular to the axis of the pole column 30, the distance between the side of the uncompressed sealing portion 44 away from the pole column 30 and the hole wall of the first through hole 11 is w3, satisfying 0.5 mm ≤ w3 ≤ 3 mm. With such a setting, while facilitating the deformation reset during the assembly process of the sealing portion 44, the sealing effect of the sealing portion 44 is ensured.

[0143] It should be noted that if w3 > 3 mm, the deformation amounts of the protruding portion 41 and the sealing portion 44 during the assembly process are too large (please refer to Figure 14 ), after the assembly is in place, it is not convenient for the deformation reset of the protruding portion 41 and the sealing portion 44, affecting the assembly quality of the upper insulating part body 40, and the insertion resistance during the assembly process is relatively large, not facilitating the assembly. If w3 < 0.5 mm, when the sealing portion 44 is assembled, the volume between the plate 10 and the bottom plate 31 is too small, and the sealing effect is poor.

[0144] In one embodiment, as Figure 13As shown, on the cross-section along the axis of the terminal post 30, the width at the connection between the sealing part 44 and the protruding part 41 is w1, satisfying 0.3 mm ≤ w1 ≤ 3 mm. With such a setting, while ensuring the overall structural strength of the upper insulating part body 40, waste of materials and increase in production costs are avoided.

[0145] It should be noted that if w1 > 3 mm, the protruding part 41 and the sealing part 44 are too thick and heavy, resulting in an increase in consumables and production costs, and it is not conducive to the lightweight design of the battery. If w1 < 0.3 mm, the connection strength between the protruding part 41 and the sealing part 44 is relatively low, and the sealing part 44 is prone to breakage and detachment during the assembly process of the sealing part 44 and the plate 10 and after the bottom plate 31 presses the sealing part 44, which is likely to lead to sealing failure.

[0146] In one embodiment, as Figure 13 shown, on the cross-section along the axis of the terminal post 30, in the direction perpendicular to the axis of the terminal post 30, the distance between the protruding part 41 and the terminal post 30 is g2, satisfying 0.05 mm ≤ g2 ≤ 0.5 mm. That is to say, the distance between the inner peripheral surface of the protruding part 41 and the outer peripheral surface of the terminal post 30 is g2. With such a setting, while facilitating the assembly of the terminal post 30, the sealing effect of the sealing part 44 is ensured.

[0147] It should be noted that if g2 > 0.5 mm, the gap between the protruding part 41 and the terminal post 30 is too large. When the bottom plate 31 presses the sealing part 44, the sealing part 44 is likely to deviate towards the center of the terminal post 30. If the deviation amount of the sealing part 44 is too large, the volume remaining between the bottom plate 31 and the plate 10 will be too small, affecting the sealing effect of the sealing part 44. If g2 < 0.05 mm, the assembly gap between the terminal post 30 and the protruding part 41 is too small, which is not conducive to the assembly of the terminal post 30.

[0148] In one embodiment, as Figure 13 shown, on the cross-section along the axis of the terminal post 30, the diameter of the uncompressed sealing part 44 is k, satisfying 0.75 mm ≤ k ≤ 4 mm. With such a setting, while facilitating the deformation and reset of the sealing part 44 during the assembly process, the sealing effect of the sealing part 44 is ensured.

[0149] It should be noted that if k > 4 mm, the deformation amount of the protruding part 41 and the sealing part 44 during the assembly process is too large (please refer to Figure 14 ), after the assembly is in place, it is not convenient for the protruding part 41 and the sealing part 44 to deform and reset, affecting the assembly quality of the upper insulating part body 40, and the resistance during the assembly process is relatively large, which is not conducive to assembly. If k < 0.75 mm, when the sealing part 44 is assembled, the volume between the plate 10 and the bottom plate 31 is too small, and the sealing effect is relatively poor.

[0150] In one embodiment, asFigure 13 As shown, in the cross-section along the axis of the pole column 30, in the axial direction of the pole column 30, the thickness of the lower plastic between the bottom plate 31 and the plate 10 is h, satisfying 0.6 mm ≤ h ≤ 2 mm, and the compression ratio of the sealing part 44 satisfies 20% ≤ (k - h) / h ≤ 50%. By limiting the value of h, while ensuring the insulation effect between the plate 10 and the pole column 30, waste of space and materials is avoided; by limiting the compression ratio of the sealing part 44, while ensuring the sealing effect of the sealing part 44, waste of materials is avoided, and extrusion damage to the plate 10 and the bottom plate 31 is avoided.

[0151] It should be noted that if h > 2 mm, the thickness of the lower plastic is too large, resulting in too large an overall thickness of the battery cover structure, reducing the space utilization rate, increasing the consumption of the lower plastic, and increasing the production cost. If h < 0.6 mm, the lower plastic is too thin, and the pole column 30 and the plate 10 are prone to electrical connection and cause a short circuit, affecting the safety performance of the battery.

[0152] It should be noted that if the compression ratio of the sealing part 44 is too large, the pressure exerted by the sealing part 44 on the plate 10 and the bottom plate 31 will be too large, easily causing the plate 10 and the bottom plate 31 to be extruded and deformed or even broken, affecting the service life of the pole column 30 and the plate 10; and, on the one hand, when the volume of the sealing part 44 is certain, if the compression ratio of the sealing part 44 is too large, it means that the distance between the plate 10 and the bottom plate 31 is too small, then the thickness of the lower plastic between the plate 10 and the bottom plate 31 will be too thin, easily causing a short circuit problem; on the other hand, when the distance between the plate 10 and the bottom plate 31 is certain, if the compression ratio of the sealing part 44 is too large, it means that the volume of the sealing part 44 is too large, resulting in an increase in consumables and thus an increase in cost. If the compression ratio of the sealing part 44 is too small, the extruded sealing part 44 cannot achieve effective sealing between the plate body and the bottom plate 31, easily causing the electrolyte to come into contact with the pole column 30 and causing the pole column 30 to be corroded.

[0153] In one embodiment, as Figure 13 shown, in the cross-section along the axis of the pole column 30, in the direction perpendicular to the axis of the pole column 30, the distance between the side of the uncompressed sealing part 44 away from the pole column 30 and the hole wall of the second through hole 51 is w2, satisfying w2 ≥ 1.5 × w3. With such a setting, it is ensured that the plate 10, the bottom plate 31, and the lower plastic can enclose to form sufficient swelling space for the deformed sealing part 44 after extrusion, ensuring that the pole column 30 can be assembled in place and ensuring the sealing effect of the sealing part 44.

[0154] According to an embodiment of the present invention, on the other hand, a lithium battery is further provided, including: a lithium battery body, and the battery cover structure as described above.

[0155] Since the lithium battery in this solution includes the above battery cover plate structure, the lithium battery in this solution includes all the beneficial effects of the above battery cover plate structure.

[0156] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A battery cover structure, characterized in that: include: A plate (10) having a first through hole (11) formed along a thickness direction; A connecting block (20) is arranged on one side of the plate (10) in the thickness direction; A pole (30) is arranged on a side of the plate (10) away from the connection block (20) in the thickness direction, and one end of the pole (30) along its own axial direction is suitable for passing through the first through hole (11) and being fixedly connected to the connection block (20); an upper insulating member body (40) made of an elastic material, the upper insulating member body (40) being arranged between the connecting block (20) and the plate (10), the upper insulating member body (40) being suitable for insulating and sealing between the connecting block (20) and the plate (10); The upper insulating member body (40) extends in a thickness direction in a direction away from the connecting block (20) to form a protruding portion (41), the protruding portion (41) being arranged between an outer peripheral wall of the pole (30) and an inner peripheral wall of the first through hole (11), the protruding portion (41) being suitable for insulating the pole (30) from the plate (10); A bottom plate (31) is provided at one end of the pole (30) which is axially away from the connection block (20); the upper insulating member body (40) further comprises a sealing portion (44) connected to the end of the protruding portion (41); the sealing portion (44) is compressed and sealed between the plate (10) and the bottom plate (31); and in a cross section along the axis of the pole (30), the uncompressed sealing portion (44) presents a circular structure.

2. The battery cover structure according to claim 1, characterized in that: In a cross section along the axis of the pole (30), along the axis direction of the pole (30), the minimum distance between the uncompressed sealing portion (44) and the plate (10) is g1, satisfying 0.2 mm ≤ g1 ≤ 1 mm; and / or, In a cross section along the axis of the pole (30), in a direction perpendicular to the axis of the pole (30), the distance z between the center of the uncompressed sealing portion (44) and the hole wall of the first through hole (11) satisfies 0.2 mm ≤ z ≤ 3 mm; and / or, In a cross section along the axis of the pole (30), along a direction perpendicular to the axis of the pole (30), the distance between the side of the uncompressed sealing portion (44) away from the pole (30) and the hole wall of the first through hole (11) is w3, satisfying 0.5 mm ≤ w3 ≤ 3 mm; and / or, In a cross section along the axis of the pole (30), the width of the connection between the sealing portion (44) and the protruding portion (41) is w1, satisfying 0.3 mm ≤ w1 ≤ 3 mm; and / or, On a cross section along the axis of the pole (30), along a direction perpendicular to the axis of the pole (30), the distance between the protrusion (41) and the pole (30) is g2, satisfying 0.05 mm ≤ g2 ≤ 0.5 mm; and / or, In a cross section along the axis of the pole (30), the diameter of the uncompressed sealing portion (44) is k, satisfying 0.75 mm ≤ k ≤ 4 mm.

3. The battery cover structure according to claim 1 or 2, characterized in that: A first recessed platform (42) is provided on one side of the upper insulating member body (40) close to the connecting block (20) in the thickness direction, and a first protrusion (21) matched with the first recessed platform (42) is provided on the connecting block (20), wherein the first protrusion (21) is suitable for being squeezed and sealed with the first recessed platform (42).

4. The battery cover structure according to claim 3, characterized in that: The compression amount of the first projection (21) on the first depression (42) is B1, and B1 satisfies 25%≤B1 / A1≤50%, wherein A1 is the initial thickness of the first depression (42), and A1 satisfies A1≥0.3 mm.

5. The battery cover structure according to claim 4, characterized in that: The depth of the first depression (42) is C1, the width of the first depression (42) is E1, C1 and E1 satisfy (E1-D1)·C1≥D1·B1, wherein D1 is the width of the first projection (21), and D1≥0.5 mm.

6. The battery cover structure according to claim 3, characterized in that: A second recessed platform (43) is provided on one side of the upper insulating member body (40) close to the plate (10) in the thickness direction, and a second protrusion (12) matched with the second recessed platform (43) is provided on the plate (10), and the second protrusion (12) is suitable for extrusion sealing with the second recessed platform (43).

7. The battery cover structure according to claim 6, characterized in that: The compression amount of the second projection (12) on the second depression (43) is B2, B2 satisfies 25%≤B2 / A2≤50%, wherein A2 is the initial thickness of the second depression (43), A2 satisfies A2≥0.3mm; and / or, The radial distance between the second sinking platform (43) and the first sinking platform (42) is F, and F satisfies 1mm≤F≤5mm.

8. The battery cover structure according to claim 7, characterized in that: The depth of the second recessed platform (43) is C2, the width of the second recessed platform (43) is E2, C2 and E2 satisfy (E2-D2)·C2≥D2·B2, wherein D2 is the width of the second protruding platform (12).

9. The battery cover structure according to claim 2, characterized in that: The battery cover structure further comprises a lower insulating member (50), one side of the lower insulating member (50) in the thickness direction abuts against the bottom plate (31), and the other side abuts against the plate (10); The lower insulating member (50) is provided with a second through hole (51) along the thickness direction; the protrusion (41) extends into the second through hole (51) along the thickness direction in a direction away from the connection block (20); the protrusion (41) is arranged between the outer peripheral wall of the pole (30) and the inner peripheral wall of the second through hole (51); In a cross section along the axis of the pole (30), along the axis direction of the pole (30), the thickness of the lower plastic between the bottom plate (31) and the plate (10) is h, satisfying 0.6 mm ≤ h ≤ 2 mm, and the compression rate of the sealing portion (44) satisfies 20% ≤ (kh) / h ≤ 50%; and / or, in a cross section along the axis of the pole (30), along a direction perpendicular to the axis of the pole (30), the distance between a side of the uncompressed sealing portion (44) away from the pole (30) and the hole wall of the second through hole (51) is w2, satisfying w2 ≥ 1.5 × w3.

10. A lithium battery, characterized in that: include: A lithium battery body and a battery cover structure as described in any one of claims 1 to 9.

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