A cover assembly

Abstract

The utility model discloses an embodiment provides a kind of cover plate assembly.Cover plate assembly includes copper pole and aluminium riveting block.Copper pole has bottom plate and the columnar portion in the bottom plate side, and bottom plate and columnar portion are integrated structure;Columnar portion includes sequentially coaxially arranged first cylinder, second cylinder and third cylinder along the direction away from bottom plate, and the diameter of second cylinder is less than the diameter of first cylinder and third cylinder, and the surface of first cylinder towards second cylinder, the part not being connected with second cylinder is first pole platform, and the surface of third cylinder towards second cylinder, the part not being connected with second cylinder is second pole platform;Aluminium riveting block is sleeved in columnar portion, and it include first part and second part;First part is embedded between first pole platform and second pole platform, and with first pole platform, second pole platform and the outer surface of second cylinder abuts;The surface of second part towards columnar portion and the sidewall of columnar portion are set predetermined interval, and product cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a cover plate assembly. Background Technology

[0002] The negative terminal of the battery needs to be welded to the negative Cu electrode tab for electrical connection, and it also needs to cooperate with the Al riveting block to bear the functions of terminal strength and internal resistance stability. Due to the large difference in melting points between Cu and Al, the connection strength between Cu terminal and Al riveting block cannot be guaranteed by conventional seam welding or through welding. Therefore, Cu-Al composite terminals are currently commonly used. In this case, the Cu part of the terminal is welded to the electrode tab, and the Al part is riveted to the riveting block and then welded. Welding the Al of the terminal and the Al of the riveting block can improve the terminal strength and increase the stability of the terminal's internal resistance.

[0003] There are two common manufacturing methods for Cu-Al composite poles: one is the composite plate method, which involves first bonding Cu and Al plates together and then processing them into the required shape; the other is the friction welding method, which involves first subjecting Cu rods and Al rods to high-speed friction to bond their end faces together and then processing them into the required shape. Both of these manufacturing methods have high process costs, which greatly increases the product cost. Utility Model Content

[0004] The purpose of this utility model embodiment is to provide a cover plate assembly to reduce product costs. The specific technical solution is as follows: This application provides a cover plate assembly including a copper electrode post and an aluminum riveting block. The copper electrode post has a base plate and a columnar portion on one side of the base plate, the base plate and the columnar portion being an integral structure; the columnar portion includes a first column, a second column, and a third column arranged coaxially in sequence along a direction away from the base plate, the diameter of the second column being smaller than the diameters of the first column and the third column, the surface of the first column facing the second column and not connected to the second column forming a first electrode post platform, the surface of the third column facing the second column and not connected to the second column forming a second electrode post platform; the aluminum riveting block is sleeved on the columnar portion, the aluminum riveting block including a first part and a second part; the first part is embedded between the first electrode post platform and the second electrode post platform, and abuts against the outer surfaces of the first electrode post platform, the second electrode post platform, and the second column; the end face of the second part protrudes from the end face of the copper electrode post, the end face of the copper electrode post being disposed opposite to the base plate, and in the radial direction of the columnar portion, the surface of the second part facing the columnar portion is spaced apart from the sidewall of the columnar portion by a predetermined interval.

[0005] In some embodiments of this application, the distance between the end face of the copper electrode post and the second electrode post platform is 0.05mm-0.4mm; and / or The distance by which the end face of the second part protrudes beyond the end face of the copper pole is 0.1mm-0.4mm.

[0006] In some embodiments of this application, the width of the first pole platform is 0.15mm-0.8mm; and / or The width of the second pole platform is 0.2mm-1mm; the predetermined interval is 0.2mm-1.5mm.

[0007] In some embodiments of this application, the edge of the copper pole is welded to the surface of the first portion near the second portion; The first part has a weld pool on its surface near the second part. The distance between the inner wall of the second part and the edge of the weld pool is 0.2mm-1.5mm. The width of the weld pool is 0.2mm-1.5mm. The depth of the weld pool is 0.2mm-1.2mm. The depth of the weld pool is the distance between the bottom and the top of the weld pool.

[0008] In some embodiments of this application, a riveting hole is provided at the center of the end face of the copper electrode post. The riveting hole is a groove located on the end face of the copper electrode post. The shape of the groove opening is circular or rectangular. The angle between the side wall of the groove and the end face of the copper electrode post is α, where 90°≤α≤150°.

[0009] In some embodiments of this application, the riveting hole satisfies: 0.2d1≤d2≤0.7d1, 0.1d3≤d1≤0.6d3, where d1 is the diameter of the circular opening of the groove or the diagonal length of the rectangular opening, d2 is the diameter of the circular bottom of the groove or the diagonal length of the rectangular bottom, and d3 is the diameter of the second column. The depth of the rivet hole is H2, where 0.21H1≤H2≤0.6H1, and H1 is the distance between the first pole platform and the end face of the copper pole, where 2.5mm≤H1≤3.5mm.

[0010] In some embodiments of this application, the second column includes a first sub-column and a second sub-column along the direction away from the base plate, the diameter of the first sub-column is smaller than the diameter of the second sub-column, the surface of the second sub-column facing the first sub-column, and the part not connected to the first sub-column is a third pole column platform; The aluminum riveting block abuts against the outer surfaces of the first pole post platform, the second pole post platform, the third pole post platform, the first sub-pillar, and the second sub-pillar.

[0011] In some embodiments of this application, the distance between the third pole platform and the end face of the copper pole is H3, where 1mm≤H3≤2mm; the width of the third pole platform is 0.15mm-0.8mm.

[0012] In some embodiments of this application, the inner wall of the through hole that abuts against the outer surface of the first sub-pillar is inclined, and the diameter of the through hole near its second part is smaller than the diameter of the through hole away from the second part. The angle between the inner wall of the through hole that abuts against the outer surface of the first sub-pillar and the axis of the through hole of the aluminum riveting block is 2°-25°.

[0013] In some embodiments of this application, a riveting hole is provided at the center of the end face of the copper electrode post. The riveting hole is a groove located on the end face of the copper electrode post. The shape of the groove opening is circular or rectangular. The angle between the side wall of the groove and the end face of the copper electrode post is α, where 90°≤α≤150°.

[0014] and / or The riveting hole satisfies: 0.2d1≤d2≤0.7d1, 0.3d4≤d1≤0.8d4, where d1 is the diameter of the circular opening of the groove or the diagonal length of the rectangular opening, d2 is the diameter of the circular bottom of the groove or the diagonal length of the rectangular bottom, and d4 is the diameter of the second sub-pillar; the depth of the riveting hole is H4,H3-0.2mm≤H4≤H3+0.8mm.

[0015] Beneficial effects: The cover plate assembly of this application embodiment includes a copper electrode post and an aluminum riveting block. A first portion of the aluminum riveting block is embedded between a first electrode post platform and a second electrode post platform, and abuts against the outer surfaces of the first electrode post platform, the second electrode post platform, and the second column. That is, the first portion of the aluminum riveting block is sandwiched between the first and second electrode post platforms of the copper electrode post, forming a sandwich structure. This mutual support and cooperation enhances the strength of the copper electrode post. Compared to Cu-Al composite electrode posts in related technologies, the copper electrode post in this application embodiment is made of pure copper, eliminating the need for copper and aluminum bonding and simplifying the copper-aluminum bonding process, thereby reducing product costs. This results in a copper-clad aluminum structure with high strength.

[0016] Of course, any product implementing this utility model does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a top view of the cover plate assembly according to an embodiment of this application; Figure 2 for Figure 1 AA cross-section view; Figure 3 Schematic diagram of the cover plate assembly Figure 1 ; Figure 4 This is a cross-sectional view of the cover plate assembly according to an embodiment of this application; Figure 5 Schematic diagram of the cover plate assembly Figure 2 ; Figure 6 This is a dimensioned drawing of the cover plate assembly according to an embodiment of this application; Figure 7 This is an exploded view of the cover plate assembly according to an embodiment of this application; Figure 8 Schematic diagram of the cover plate assembly Figure 3 ; Figure 9 This is a schematic diagram of the welding process. Figure 10 This is a schematic diagram of the structure before riveting for the first riveting method; Figure 11 This is a schematic diagram of the structure before riveting for the second riveting method.

[0019] Explanation of reference numerals in the attached figures: Copper pole 100; Copper pole end face 101; Riveting hole 102; Protrusion 103; Base plate 110; Columnar part 120; First column 121; Second column 122; First sub-column 1221; Second sub-column 1222; Third column 123; First pole platform 124; Second pole platform 125; Third pole platform 126; Aluminum riveting block 200; Through hole 201; Through hole 201 of the first part; Through hole 2011 of the first sub-part; Through hole 2012 of the second sub-part; Through hole 202 of the second part; First part 210; First sub-part 211; Second sub-part 212; Second part 220; End face 221 of the second part; Upper plastic 300; Cover plate body 400; Sealing ring 500; Lower plastic 600; Weld pool 700. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art based on this application are within the protection scope of the present utility model.

[0021] The battery in this embodiment includes a casing, a cell module, and a cover assembly. The casing has an upper opening, the cell module is disposed inside the casing, and the cover assembly closes the upper opening. The cover assembly includes a positive electrode structure and a negative electrode structure.

[0022] The purpose of this application is to provide a cover plate assembly that can reduce costs and has high strength. An embodiment of this application provides a cover plate assembly including a copper pole and an aluminum riveting block. Specifically, the copper electrode post has a base plate and a columnar portion on one side of the base plate, the base plate and the columnar portion being an integral structure; the columnar portion includes a first column, a second column, and a third column arranged coaxially in sequence along the direction away from the base plate, the diameter of the second column being smaller than the diameters of the first column and the third column, the surface of the first column facing the second column and the portion not connected to the second column being the first electrode platform, the surface of the third column facing the second column and the portion not connected to the second column being the second electrode platform; the first electrode platform is the surface of the first column away from the base plate; the second electrode platform is the surface of the third column facing the base plate; an aluminum riveting block is sleeved on the columnar portion, the aluminum riveting block including a first part and a second part; the first part is embedded between the first electrode platform and the second electrode platform, and abuts against the outer surfaces of the first electrode platform, the second electrode platform, and the second column; the end face of the second part protrudes from the end face of the copper electrode post, the end face of the copper electrode post being opposite to the base plate, and in the radial direction of the columnar portion, the surface of the second part facing the columnar portion is spaced at a predetermined interval from the side wall of the columnar portion.

[0023] The cover plate assembly of this application embodiment includes a copper electrode post and an aluminum riveting block. A first portion of the aluminum riveting block is embedded between a first electrode post platform and a second electrode post platform, and abuts against the outer surfaces of the first electrode post platform, the second electrode post platform, and the second column. That is, the first portion of the aluminum riveting block is sandwiched between the first and second electrode post platforms of the copper electrode post, forming a sandwich structure. This mutual support and cooperation enhances the strength of the copper electrode post. Compared to Cu-Al composite electrode posts in related technologies, the copper electrode post in this application embodiment is made of pure copper, eliminating the need for copper and aluminum bonding and simplifying the copper-aluminum bonding process, thereby reducing product costs. This results in a copper-clad aluminum structure with high strength.

[0024] The structure of the cover plate assembly according to the embodiments of this application will be described below.

[0025] Figure 1 A top view of a cover plate assembly according to an embodiment of this application is shown, wherein a negative electrode structure and a positive electrode structure are mounted on the cover plate. Figure 2 for Figure 1 The AA cross-sectional view shows that the copper pole 100 and the aluminum riveting block 200 form a sandwich structure.

[0026] Figure 3 Schematic diagram of the cover plate assembly Figure 1 ,yes Figure 2 A partially enlarged schematic diagram at point P. The copper pole post 100 includes a base plate 110 and a columnar portion 120, which are integrally formed. The columnar portion 120 includes a first column 121, a second column 122, and a third column 123 arranged coaxially in sequence along a direction away from the base plate 110. The diameter of the second column 122 is smaller than the diameters of the first column 121 and the third column 123. The surface of the first column 121 facing the second column 122, and the portion not connected to the second column 122, forms the first pole post platform 124. The surface of the third column 123 facing the second column 122, and the portion not connected to the second column 122, forms the second pole post platform 125. An aluminum riveting block 200 is sleeved on the columnar portion 120. The aluminum riveting block 200 includes a first part 210 and a second part 220. Figure 3 The first part 210 and the second part 220 are divided by a dashed line. The first part 210 is embedded between the first pole post platform 124 and the second pole post platform 125 and abuts against the outer surfaces of the first pole post platform 124, the second pole post platform 125 and the second column 122. The end face 221 of the second part protrudes from the end face 101 of the copper pole post. The end face 101 of the copper pole post is disposed opposite to the base plate 110. In the radial direction of the columnar part 120, the surface of the second part 220 facing the columnar part 120 is spaced apart from the side wall of the columnar part 120.

[0027] Those skilled in the art will understand that this application can be implemented by riveting. For example, a copper electrode post is first prepared, comprising a base plate and a columnar portion. The columnar portion is divided into a first part and a second part along a direction away from the base plate. The diameter of the second part is smaller than the diameter of the first part. A first electrode post platform 124 is provided between the first part and the second part. The aluminum riveting block 200 comprises a first part 210 and a second part 220, and has a through hole. The inner diameter of the through hole 201 of the first part of the aluminum riveting block 200 matches the diameter of the second part of the copper electrode post, and the inner diameter of the through hole 202 of the second part of the aluminum riveting block 200 is larger than the diameter of the second part of the copper electrode post. The copper electrode post can be inserted into the through hole 201 of the aluminum riveting block 200. Before riveting, the end face of the copper electrode post protrudes from the upper surface of the first part 210 of the aluminum riveting block 200, and even protrudes from the upper surface of the second part 220 of the aluminum riveting block 200, so that the lower surface of the aluminum riveting block 200 near the copper electrode post contacts the first electrode post platform 124. After the copper pole and the aluminum riveting block 200 are inserted into place, they are riveted on top of the copper pole to form a second pole platform 125. The aluminum riveting block 200 is embedded between the first pole platform 124 and the second pole platform 125 and abuts against the outer surface of the first pole platform 124, the second pole platform 125 and the copper pole to form a "sandwich structure".

[0028] like Figure 3 As shown, the cover plate assembly also includes an upper plastic 300, a cover plate body 400, a sealing ring 500, and a lower plastic 600 located between the aluminum riveting block 200 and the base plate 110.

[0029] In some embodiments of this application, such as Figure 3 As shown, the distance H5 between the copper electrode end face 101 and the second electrode platform 125 is 0.05mm-0.4mm, so that the part of the copper electrode 100 above the first electrode platform 124 has a certain thickness to ensure that the copper electrode 100 is firmly connected to the aluminum riveting block 200.

[0030] In some embodiments of this application, the edge of the copper electrode post 100 is welded to the surface of the first portion 210 near the second portion 220. The welding method provides a stable connection. Specifically, the copper electrode post 100 and the aluminum riveting block 200 can be fixed by riveting followed by welding.

[0031] When the welding is fixed, the minimum value of the H5 range of 0.05mm can ensure that the copper pole 100 has enough material to melt and cover the surface of the first part 210 of the aluminum riveting block 200 near the second part 220. The maximum value of the H5 range of 0.4mm can avoid the problem of uneven distribution of molten droplets and easy cooling during the welding process due to the excessive height of the copper pole 100, which affects the welding effect.

[0032] In some embodiments of this application, such as Figure 3 As shown, the distance H6 by which the end face 221 of the second part protrudes from the end face 101 of the copper terminal post is 0.1mm-0.4mm. Setting the value within the above range can prevent the copper terminal post 100 from protruding from the aluminum riveting block 200 and interfering with the assembly welding of the BSB (Busbar, battery module laser welding).

[0033] In some embodiments of this application, such as Figure 3 As shown, the width W2 of the first pole platform 124 is 0.15mm-0.8mm, and the width W1 of the second pole platform 125 is 0.2mm-1mm. The minimum value of W2 ensures that the first pole platform 124 is set wider, thereby increasing the strength of the copper pole 100. The larger W2 is, the larger the diameter of the first column 121 of the copper pole 100. The maximum value of W2 limits the diameter of the first column 121 of the copper pole 100, thus saving copper material costs. Furthermore, after the sealing ring 500 is fitted onto the copper pole 100, it deforms. After deformation, its inner diameter will be the same as the maximum diameter of the copper pole 100. If the maximum diameter is too large, the inner diameter of the sealing ring 500 after deformation will be too large, resulting in greater compression deformation of the sealing ring 500 and greater rebound force, which is detrimental to long-term use and maintaining the strength of the copper pole 100. Therefore, the maximum value of W2 is limited in this embodiment, thereby limiting the maximum diameter of the copper electrode post 100, which is beneficial to the long-term use of the sealing ring 500 and the maintenance of the strength of the copper electrode post 100.

[0034] In some embodiments of this application, such as Figure 3 As shown, the predetermined interval L1 is 0.2mm-1.5mm. The minimum value of L1 ensures that the inner wall of the second part 220 does not contact the periphery of the third column 123 of the copper pole 100, preventing the molten pool from affecting the BSB welding interface. The maximum value of L1 is considered to ensure that the BSB welding has sufficient width when the diameter of the copper pole 100 and the size of the aluminum riveting block 200 are fixed.

[0035] In some embodiments of this application, such as Figure 3 As shown, a riveting hole 102 is provided at the center of the copper electrode end face 101. The riveting hole 102 is a groove located on the copper electrode end face 101. The shape of the groove opening is circular or rectangular, and the angle between the side wall of the groove and the copper electrode end face 101 is α, 90°≤α≤150°. When the copper electrode 100 includes the riveting hole 102, it facilitates the flow of Cu material during the riveting process. Simultaneously, the riveting hole 102 can, as needed, serve the purpose of CCD (Charge Coupled Device) identification and positioning during BSB welding. The inclined side wall of the groove facilitates the extrusion of material during riveting.

[0036] Specifically, the riveting hole 102 can be a conical hole, a cylindrical hole, a square prism hole, or an inverted frustum-shaped hole, with corresponding cross-sectional shapes of conical, cylindrical, rectangular, and inverted trapezoidal, respectively. An inverted frustum-shaped hole is preferred, which is a cylindrical shape with unequal cross-sectional diameters to facilitate material extrusion. Furthermore, the unequal upper and lower diameters facilitate CCD identification of one of the diameter dimensions during positioning, preventing confusion.

[0037] In some embodiments of this application, such as Figure 3 As shown, the riveting hole 102 satisfies: 0.2d1≤d2≤0.7d1, where d1 is the diameter of the circular opening of the groove or the diagonal length of the rectangular opening, and d2 is the diameter of the circular bottom of the groove or the diagonal length of the rectangular bottom. The minimum value of the above range ensures that the groove has a large space to facilitate riveting and extrusion, while the maximum value of the above range can avoid insufficient copper around the groove, thereby ensuring the strength of the copper pole 100. The riveting hole 102 satisfies: 0.1d3≤d1≤0.6d3, where d3 is the diameter of the second column 122. The minimum value of d1 makes the size of the riveting hole 102 larger, which facilitates the extrusion of the copper pole 100 to the end face of the first part 210 during riveting, as well as the contact between the copper pole 100 and the edge of the through hole 201 of the aluminum riveting block 200. If the riveting hole 102 is too large, it may reduce the strength of the pole. The maximum value of d1 ensures that the size of the riveting hole 102 is not too large, thereby not affecting the strength of the copper pole 100. The depth of the riveting hole 102 is H2, 0.21H1≤H2≤0.6H1, where H1 is the distance between the second pole platform 125 and the end face 101 of the copper pole, so that the size of the riveting hole 102 is relatively large, which facilitates the extrusion of the copper pole 100 onto the end face of the first part 210 during riveting, and the contact between the copper pole 100 and the edge of the through hole 201 of the aluminum riveting block 200; 2.5mm≤H1≤3.5mm.

[0038] Figure 4 This is a cross-sectional view of a cover plate assembly according to an embodiment of this application, wherein the negative electrode structure and the positive electrode structure are mounted on the cover plate. Figure 5 Schematic diagram of the cover plate assembly Figure 2 In the cover plate assembly, the copper pole 100 and the aluminum riveting block 200 form another sandwich structure.

[0039] Figure 5 yes Figure 4A partially enlarged schematic diagram at point Q shows that the copper pole 100 includes a base plate 110 and a columnar portion 120, which are integrally formed. The columnar portion 120 includes a first column 121, a second column 122, and a third column 123 arranged coaxially in sequence along a direction away from the base plate 110. Along a direction away from the base plate 110, the second column 122 is divided into a first sub-column 1221 and a second sub-column 1222. The diameter of the first sub-column 1221 is smaller than the diameter of the first column 122, and the diameter of the second sub-column 1222 is larger than the diameter of the first sub-column 1221. The diameter of the second sub-column 1222 is... The diameter is smaller than the diameter of the third column 123; the surface of the first column 121 facing the first sub-column 1221, the part not connected to the first sub-column 1221 is the first pole column platform 124; the surface of the third column 123 facing the second sub-column 1222, the part not connected to the second sub-column 1222 is the second pole column platform 125; the surface of the second sub-column 1222 facing the first sub-column 1221, the part not connected to the first sub-column 1221 is the third pole column platform 126; the aluminum riveting block 200 is sleeved on the columnar portion 120, and the aluminum riveting block 200 includes a first part 210 and a second part 220. Figure 5 The first part 210 and the second part 220 are divided by a dashed line. The first part 210 is embedded between the first pole post platform 124 and the second pole post platform 125, and abuts against the outer surfaces of the first pole post platform 124, the second pole post platform 125, the third pole post platform 126, the first sub-pillar 1221, and the second sub-pillar 1222. The end face 221 of the second part protrudes from the end face 101 of the copper pole post, and the end face 101 of the copper pole post is opposite to the base plate 110. In the radial direction of the columnar portion 120, the surface of the second part 220 facing the columnar portion 120 is spaced at a predetermined distance from the side wall of the columnar portion 120. This forms a double-layer sandwich structure, further enhancing the strength of the copper pole post 100.

[0040] The upper plastic 300, the cover plate body 400, the sealing ring 500, and the lower plastic 600 are located between the aluminum riveting block 200 and the base plate 110.

[0041] Those skilled in the art will understand that this application can be implemented by riveting. For example, a copper pole post is first prepared, comprising a base plate and a columnar portion, wherein the columnar portion is divided into a first part and a second part along a direction away from the base plate, the diameter of the second part being smaller than the diameter of the first part, and a first pole post platform 124 is provided between the first part and the second part. The aluminum riveting block 200 includes a first part 210 and a second part 220. Along a direction away from the second part 220 of the aluminum riveting block 200, the first part 210 of the aluminum riveting block 200 is divided into a second sub-part 212 and a first sub-part 211. The inner diameter of the through hole 2011 of the first sub-part of the aluminum riveting block 200 is smaller than the inner diameter of the through hole 2012 of the second sub-part of the aluminum riveting block 200, and the inner diameter of the through hole 2012 of the second sub-part of the aluminum riveting block 200 is smaller than the inner diameter of the through hole 202 of the second part of the aluminum riveting block 200. The inner diameter of the aluminum riveting block 200 and the inner diameter of the through hole 202 of the second part are both larger than the diameter of the second part of the copper pole. The inner diameter of the through hole 2011 of the first sub-part of the aluminum riveting block 200 matches the diameter of the second part of the copper pole. The copper pole can be inserted into the through hole 2011 of the first sub-part of the aluminum riveting block 200. Before riveting, the end face of the copper pole protrudes from the upper surface of the second sub-part 212 of the aluminum riveting block 200, and even protrudes from the upper surface of the second part 220 of the aluminum riveting block 200, so that the lower surface of the aluminum riveting block 200 near the copper pole contacts the first pole platform 124. After the copper pole and the aluminum riveting block 200 are inserted into place, they are riveted on top of the copper pole to form the second pole platform 125 and the third pole platform 126. The aluminum riveting block 200 is embedded between the first pole platform 124 and the second pole platform 125, and abuts against the outer surfaces of the first pole platform 124, the second pole platform 125, the third pole platform 126, the first sub-pole 1221, and the second sub-pole 1222, forming a "double-layer sandwich structure".

[0042] In some embodiments of this application, such as Figure 6 As shown, Figure 6 The diagram shows the dimensions of the cover plate assembly according to an embodiment of this application. The distance between the third pole platform 126 and the copper pole end face 101 is H3, where 1mm ≤ H3 ≤ 2mm. The width W3 of the third pole platform 126 is 0.15mm-0.8mm. The minimum value of W3 ensures that the width of the third pole platform 126 is relatively large, thereby increasing the strength of the copper pole 100. Since Cu is relatively hard, it is difficult to radially extrude too much above the third pole platform 126. The maximum value of W3 ensures that the third pole platform 126 is not too large, so that the second sub-pole 1222 of the copper pole 100 can more easily contact the sidewall of the through hole 2012 of the second sub-part of the aluminum riveting block 200.

[0043] The maximum diameters of the first pole post platform 124, the second pole post platform 125, and the third pole post platform 126 are all larger than the diameter of the through hole 2011 of the first sub-part of the aluminum riveting block 200, so as to ensure that the copper pole post 100 can form a mating relationship with the aluminum riveting block 200 after riveting, thereby enhancing the strength of the copper pole post 100.

[0044] In some embodiments of this application, such as Figure 5 and Figure 6 As shown, a riveting hole 102 is provided at the center of the copper electrode end face 101. The riveting hole 102 is a groove located on the copper electrode end face 101. The shape of the groove opening is circular or rectangular, and the angle between the side wall of the groove and the copper electrode end face 101 is α, 90°≤α≤150°. The presence of the riveting hole 102 on the copper electrode 100 facilitates the flow of Cu material during the riveting process. Simultaneously, the riveting hole 102 can serve as a CCD identification and positioning tool during BSB welding, as needed. The inclined side wall of the groove facilitates material extrusion during riveting.

[0045] In some embodiments of this application, such as Figure 5 and Figure 6 As shown, the riveting hole 102 satisfies: 0.2d1≤d2≤0.7d1, where d1 is the diameter of the circular opening of the groove or the diagonal length of the rectangular opening, and d2 is the diameter of the circular bottom of the groove or the diagonal length of the rectangular bottom. The minimum value of the above range ensures that the groove has a large space for riveting and extrusion, and the maximum value of the above range can avoid insufficient copper around the groove, thereby ensuring the strength of the copper pole 100. The riveting hole 102 satisfies: 0.3d4≤d1≤0.8d4, where d4 is the diameter of the second sub-pillar 1222. The copper pole 100 is relatively hard, and the minimum value of d1 makes the size of the riveting hole 102 larger, ensuring that the copper pole 100 can be riveted and extruded to contact the aluminum riveting block 200. If the riveting hole 102 is too large, it may reduce the strength of the pole. The maximum value of d1 ensures that the size of the riveting hole 102 is not too large, thereby not affecting the strength of the copper pole 100. The depth of the rivet hole 102 is H4, H3-0.2mm≤H4≤H3+0.8mm, that is, as shown below. Figure 6 As shown by the dotted line on the upper side, the deepest point of the riveting hole 102 is not lower than the third pole platform 126. The height difference between the deepest point of the riveting hole 102 and the third pole platform 126 is 0-0.2mm, ensuring that the riveting hole 102 is not too shallow and has a relatively large space to facilitate riveting and extrusion. Figure 6As shown by the dotted line on the lower side, the deepest point of the riveting hole 102 is not higher than the third pole platform 126, making the riveting hole 102 relatively deep and with a large space to facilitate riveting and extrusion. The height difference between the deepest point of the riveting hole 102 and the third pole platform 126 is 0-0.8mm. The maximum value of the above range ensures that the riveting hole 102 is not too deep and that the remaining copper in the copper pole 100 is not too little, thereby ensuring the strength of the copper pole 100.

[0046] Preferably, the deepest position of the riveting hole 102 is lower than the third pole platform 126, making the riveting hole 102 deeper and with a larger space, which makes it easier to rivet the copper pole 100. This facilitates the copper pole 100 being squeezed to the side wall of the through hole 201 of the aluminum riveting block 200 after riveting, thereby enhancing the strength of the copper pole 100.

[0047] In some embodiments of this application, the numerical ranges of the distance H5 between the copper electrode end face 101 and the second electrode platform 125, the distance H6 between the end face 221 of the second part and the copper electrode end face 101, the width W2 of the first electrode platform 124, the width W1 of the second electrode platform 125, and the predetermined interval L1 can be the same as in the aforementioned embodiments. Furthermore, in this embodiment, the edge of the copper electrode 100 is welded to the surface of the second sub-part 212 near the second part 220. When fixed by welding, the minimum value of H5 (0.05 mm) ensures that the copper electrode 100 has sufficient material to melt and cover the surface of the second sub-part 212 of the aluminum riveting block 200 near the second part 220, while the maximum value of H5 (0.4 mm) avoids problems such as uneven distribution of molten droplets and easy cooling during welding due to excessive height of the copper electrode 100, which affects the welding effect.

[0048] Figure 7 The diagram shows an exploded view of the cover plate assembly according to an embodiment of this application. It should be noted that the exploded view of the cover plate assembly in the foregoing embodiment is different from... Figure 7 Similarly, only the shape of the columnar portion 120 and the shape of the through hole in the aluminum riveting block 200 are the same. Figure 7 The shapes shown are different; please refer to the previous description for specific shapes, which will not be repeated here. Figure 8 Schematic diagram of the cover plate assembly Figure 3 In the cover plate assembly, the copper pole 100 and the aluminum riveting block 200 form a third sandwich structure.

[0049] like Figure 8As shown, the copper pole post 100 includes a base plate 110 and a columnar portion 120, which are integrally formed. The columnar portion 120 includes a first column 121, a second column 122, and a third column 123 arranged coaxially in sequence along a direction away from the base plate 110. Along a direction away from the base plate 110, the second column 122 is divided into a first sub-column 1221 and a second sub-column 1222. The outer surface of the first sub-column 1221 is inclined. The diameter of the first sub-column 1221 near the base plate 110 is larger than its diameter away from the base plate 110. The maximum diameter of the first sub-column 1221 is smaller than the diameter of the first column 121. The diameter of the second sub-column 1222 is larger than the diameter of the first sub-column 1222. The minimum diameter of column 1221 is smaller than the diameter of the second sub-column 1222, which is smaller than the diameter of the third column 123. The surface of the first column 121 facing the first sub-column 1221, and the portion not connected to the first sub-column 1221, forms the first pole platform 124. The surface of the third column 123 facing the second sub-column 1222, and the portion not connected to the second sub-column 1222, forms the second pole platform 125. The surface of the second sub-column 1222 facing the first sub-column 1221, and the portion not connected to the first sub-column 1221, forms the third pole platform 126. An aluminum riveting block 200 is fitted onto the columnar portion 120. The aluminum riveting block 200 includes a first portion 210 and a second portion 220. Figure 8 The first part 210 and the second part 220 are divided by a dashed line. The first part 210 is embedded between the first pole post platform 124 and the second pole post platform 125, and abuts against the outer surfaces of the first pole post platform 124, the second pole post platform 125, the third pole post platform 126, the first sub-pillar 1221, and the second sub-pillar 1222. The end face 221 of the second part protrudes from the end face 101 of the copper pole post, and the end face 101 of the copper pole post is opposite to the base plate 110. In the radial direction of the columnar portion 120, the surface of the second part 220 facing the columnar portion 120 is spaced at a predetermined distance from the side wall of the columnar portion 120. This forms a double-layer sandwich structure, further enhancing the strength of the copper pole post 100.

[0050] The upper plastic 300, the cover plate body 400, the sealing ring 500, and the lower plastic 600 are located between the aluminum riveting block 200 and the base plate 110.

[0051] Those skilled in the art will understand that this application can be implemented by riveting. For example, a copper pole is first prepared, comprising a base plate and a columnar portion, wherein the columnar portion is divided into a first part and a second part along a direction away from the base plate, the diameter of the second part being smaller than the diameter of the first part, and a first pole plate platform 124 is provided between the first part and the second part. The aluminum riveting block 200 includes a first part 210 and a second part 220. Along a direction away from the second part 220 of the aluminum riveting block 200, the first part 210 of the aluminum riveting block 200 is divided into a second sub-part 212 and a first sub-part 211. The inner wall of the through hole 2011 of the first sub-part of the aluminum riveting block 200 is inclined, and the inner diameter of the through hole 2011 of the first sub-part away from the second part 220 of the aluminum riveting block 200 is larger than the inner diameter of the second part 220 near the aluminum riveting block 200. The minimum inner diameter of the through hole 2011 of the first sub-part of the aluminum riveting block 200 is smaller than the inner diameter of the through hole 2012 of the second sub-part of the aluminum riveting block 200. The inner diameter of the through hole 2012 of the second sub-part of the aluminum riveting block 200 is smaller than the inner diameter of the through hole 202 of the second part of the aluminum riveting block 200. The inner diameters of the through holes 2012 and 202 of the second part of the aluminum riveting block 200 are both larger than the diameter of the second part of the copper pole post. The minimum inner diameter of the through hole 2011 of the first sub-part of the aluminum riveting block 200 matches the diameter of the second part of the copper pole post. The copper pole can be inserted into the through hole 2011 of the first sub-part of the aluminum riveting block 200. Before riveting, the end face of the copper pole protrudes from the upper surface of the second sub-part 212 of the aluminum riveting block 200, and even protrudes from the upper surface of the second part 220 of the aluminum riveting block 200. The lower surface of the aluminum riveting block 200 near the copper pole contacts the first pole platform 124. The aluminum riveting block 200 is embedded between the first pole platform 124 and the second pole platform 125, and abuts against the first pole platform 124, the second pole platform 125, the third pole platform 126, and the outer surfaces of the first sub-pillar 1221 and the second sub-pillar 1222, forming a "double-layer sandwich structure".

[0052] In some embodiments of this application, the inner wall of the through hole (through hole 2011 of the first sub-part) that abuts against the outer surface of the aluminum riveting block 200 and the first sub-pillar 1221 is inclined, and the diameter of the through hole of the aluminum riveting block 200 near its second part 220 is smaller than the diameter of the through hole away from the second part.

[0053] The angle β between the inner wall of the through hole 2011, which abuts against the outer surface of the first sub-pillar 1221, and the axis of the through hole of the aluminum riveting block 200 is 2°-25°.

[0054] The minimum value of β results in a larger inclination angle on the inner wall of the through hole 2011 of the first sub-part, which can disperse the force on the first sub-part 211 of the aluminum riveting block 200 during the riveting process. This prevents the step surface between the first sub-part 211 and the second sub-part 212 of the aluminum riveting block 200 from being squeezed out after the copper pole 100 is extruded and riveted. The maximum value of β can avoid an excessively large inclination angle, making it easier for the copper material to be squeezed to the step surface between the first sub-part 211 and the second sub-part 212 of the aluminum riveting block 200, thereby forming a sufficiently wide third pole platform 126 and enhancing the strength of the copper pole 100.

[0055] In this embodiment, the distance H5 between the copper electrode end face 101 and the second electrode platform 125, the distance H6 between the end face 221 of the second part and the copper electrode end face 101, the width W2 of the first electrode platform 124, the width W1 of the second electrode platform 125, and the numerical range of the predetermined interval L1 can be the same as in the previous embodiment. In this embodiment, a riveting hole 102 can be provided at the copper electrode end face 101. The riveting hole 102 is a groove located on the copper electrode end face 101. The angle α between the sidewall of the groove and the copper electrode end face 101, the relationship between the dimensions d1 and d2 of the riveting hole 102, the relationship between d1 and the diameter d4 of the second sub-pillar 1222, and the numerical range of the depth H4 of the riveting hole 102 can be the same as in the previous embodiment. Figure 6 The same applies to the illustrated embodiment. In this embodiment, the edge of the copper electrode 100 is welded to the surface of the second sub-part 212 near the second part 220. With the welding fixed in place, the minimum value of the H5 range (0.05 mm) ensures that the copper electrode 100 has sufficient material to melt and cover the surface of the second sub-part 212 of the aluminum riveting block 200 near the second part 220, while the maximum value of the H5 range (0.4 mm) avoids problems such as uneven distribution of molten droplets and easy cooling during welding due to excessive height of the copper electrode 100, which could affect the welding effect.

[0056] like Figure 7 and Figure 8 As shown, the upper plastic 300, cover plate body 400, sealing ring 500, and lower plastic 600 may all have through holes to allow the copper electrode 100 to pass through. The lower plastic 600, cover plate body 400, and upper plastic 300 are arranged sequentially away from the base plate 110. One end of the upper plastic 300 near the base plate 110 extends into the through hole in the cover plate body 400 to accommodate the copper electrode 100, sandwiched between the copper electrode 100 and the wall of the through hole. The other end of the upper plastic 300 away from the base plate 110 extends to the outer wall of the aluminum riveting block 200. The sealing ring 500 is located within the through hole in the lower plastic 600 to accommodate the copper electrode 100, providing a sealing function.

[0057] The structure and arrangement of the upper plastic 300, cover plate body 400, sealing ring 500 and lower plastic 600 in the foregoing embodiments of this application can be the same.

[0058] In some embodiments of this application, such as Figure 9 As shown, Figure 9 For the welding diagram, a weld pool 700 exists on the surface of the first part 210 of the aluminum riveting block 200 near the second part 220 of the aluminum riveting block 200. The distance L2 between the inner wall of the second part 220 and the edge of the weld pool 700 is 0.2mm-1.5mm. The width L3 of the weld pool 700 is 0.2mm-1.5mm. The depth H7 of the weld pool 700 is 0.2mm-1.2mm. The depth H7 of the weld pool 700 is the distance between the bottom and top of the weld pool 700. The width and depth of the weld pool 700 are within the above ranges to ensure welding strength.

[0059] like Figure 9 As shown by the arrow on the right, during the welding process, the top of the copper electrode 100 melts and extends outward along its radial direction; since the melting point of copper is higher than that of aluminum, the surface of the first part 210 of the aluminum riveting block 200 near the second part 220 is also affected by the heat of the molten copper electrode 100 and melts, forming a shape as shown by the arrow on the right. Figure 9 The copper-aluminum mixed weld pool 700 is shown. It should be noted that the weld pool 700 is obtained after the molten pool has solidified.

[0060] After the copper in the copper electrode 100 is melted, it will at least partially cover the surface of the aluminum riveting block 200. If the weld width is large enough, Cu molten beads may also penetrate into the interface between the aluminum riveting block 200 and the copper electrode 100. After solidification, they can increase the bonding strength between the two and improve the strength of the copper electrode 100 and the stability of the internal resistance of the negative terminal.

[0061] It is understandable that the above Figure 9 The content shown illustrates the structure and numerical range of the weld pool 700 using this embodiment as an example. The structure and numerical range of the weld pool 700 in the aforementioned embodiments can be the same as those in this embodiment.

[0062] like Figure 10 As shown, Figure 10 This is a schematic diagram of the structure before riveting, as shown below. Figure 10 As can be seen, the end face of the copper electrode post 100 is flat before riveting, and the riveting is carried out directly on top of the copper electrode post.

[0063] This application also provides another riveting method, see [link to relevant documentation]. Figure 11 This is a schematic diagram of the structure before the second type of riveting. Figure 11 Before riveting, the end edge of the copper pole post is provided with a protrusion 103. During riveting, the protrusion 103 is first folded away from the center of the copper pole post before riveting.

[0064] Figure 10 and Figure 11 The structure of the aluminum riveting block 200 is consistent with... Figure 8 The embodiments shown are the same, and it is understood that the above two riveting methods are applicable to all the foregoing embodiments. Furthermore, as shown in 10 and... Figure 11 The copper poles 100 do not include riveting holes. In some other embodiments of this application, riveting holes may be provided on the copper poles 100 before riveting is performed using one of the two riveting methods described above. The shape and size of the riveting holes can be found in the preceding description.

[0065] This application provides a battery that includes a cover assembly from any of the above embodiments.

[0066] The battery of this application embodiment includes the cover plate assembly of any of the above embodiments. The increased strength of the copper terminal 100 of the cover plate assembly improves the battery's operational stability. The reduced cost of the cover plate assembly lowers the overall cost of the battery. Specifically, the battery of this application embodiment can be a prismatic battery or other single-cell battery.

[0067] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model are included within the scope of protection of this utility model.

Claims

1. A cover plate assembly, characterized in that, include: A copper pole post (100) has a base plate (110) and a columnar portion (120) on one side of the base plate (110), wherein the base plate (110) and the columnar portion (120) are integral structures; the columnar portion includes a first column (121), a second column (122) and a third column (123) arranged coaxially in sequence along a direction away from the base plate (110), wherein the diameter of the second column (122) is smaller than the diameter of the first column (121) and the third column (123), the surface of the first column (121) facing the second column (122) and the part not connected to the second column (122) is a first pole post platform (124), and the surface of the third column (123) facing the second column (122) and the part not connected to the second column (122) is a second pole post platform (125). An aluminum riveting block (200) is fitted onto the columnar portion (120). The aluminum riveting block (200) includes a first part (210) and a second part (220). The first part (210) is embedded between the first pole post platform (124) and the second pole post platform (125) and abuts against the outer surfaces of the first pole post platform (124), the second pole post platform (125) and the second column (122). The end face (221) of the second part protrudes from the end face (101) of the copper pole post. The end face (101) of the copper pole post is disposed opposite to the base plate (110). In the radial direction of the columnar portion (120), the surface of the second part (220) facing the columnar portion (120) is spaced at a predetermined distance from the side wall of the columnar portion (120).

2. The cover plate assembly according to claim 1, characterized in that, The distance between the copper pole end face (101) and the second pole platform (125) is 0.05mm-0.4mm; and / or The end face (221) of the second part protrudes from the end face (101) of the copper pole by a distance of 0.1mm-0.4mm.

3. The cover plate assembly according to claim 1, characterized in that, The width of the first pole plate platform (124) is 0.15mm-0.8mm; and / or The width of the second pole platform (125) is 0.2mm-1mm; the predetermined interval is 0.2mm-1.5mm.

4. The cover plate assembly according to claim 1, characterized in that, The edge of the copper pole (100) is welded to the surface of the first portion (210) near the second portion (220); The first part (210) has a weld pool (700) on its surface near the second part (220). The distance between the inner wall of the second part (220) and the edge of the weld pool (700) is 0.2mm-1.5mm. The width of the weld pool (700) is 0.2mm-1.5mm. The depth of the weld pool (700) is 0.2mm-1.2mm. The depth of the weld pool (700) is the distance between the bottom and top of the weld pool (700).

5. The cover plate assembly according to claim 1, characterized in that, A rivet hole (102) is provided at the center of the end face (101) of the copper electrode post. The rivet hole (102) is a groove located on the end face (101) of the copper electrode post. The opening of the groove is circular or rectangular. The angle between the side wall of the groove and the end face (101) of the copper electrode post is α, where 90°≤α≤150°.

6. The cover plate assembly according to claim 5, characterized in that, The riveting hole (102) satisfies: 0.2d1≤d2≤0.7d1, 0.1d3≤d1≤0.6d3, where d1 is the diameter of the circular opening of the groove or the diagonal length of the rectangular opening, d2 is the diameter of the circular bottom of the groove or the diagonal length of the rectangular bottom, and d3 is the diameter of the second column (122). The depth of the rivet hole (102) is H2, 0.21H1≤H2≤0.6H1, where H1 is the distance between the first pole platform (124) and the end face (101) of the copper pole, 2.5mm≤H1≤3.5mm.

7. The cover plate assembly according to any one of claims 1-4, characterized in that, The second column (122) includes a first sub-column (1221) and a second sub-column (1222) in a direction away from the base plate (110). The diameter of the first sub-column (1221) is smaller than the diameter of the second sub-column (1222). The surface of the second sub-column (1222) facing the first sub-column (1221) is a third pole column platform (126). The aluminum riveting block (200) abuts against the outer surfaces of the first pole post platform (124), the second pole post platform (125), the third pole post platform (126), the first sub-pillar (1221), and the second sub-pillar (1222).

8. The cover plate assembly according to claim 7, characterized in that, The distance between the third pole platform (126) and the copper pole end face (101) is H3, 1mm≤H3≤2mm; the width of the third pole platform (126) is 0.15mm-0.8mm.

9. The cover plate assembly according to claim 7, characterized in that, The inner wall of the through hole that abuts against the outer surface of the first sub-pillar (1221) of the aluminum riveting block (200) is inclined, and the diameter of the through hole of the aluminum riveting block (200) near its second part (220) is smaller than the diameter of the through hole away from the second part (220). The angle between the inner wall of the through hole that abuts the outer surface of the aluminum riveting block (200) and the outer surface of the first sub-pillar (1221) and the axis of the through hole of the aluminum riveting block (200) is 2°-25°.

10. The cover plate assembly according to claim 7, characterized in that, A rivet hole (102) is provided at the center of the copper electrode end face (101). The rivet hole (102) is a groove located on the copper electrode end face (101). The shape of the groove opening is circular or rectangular. The angle between the side wall of the groove and the copper electrode end face (101) is α, 90°≤α≤150°. and / or The riveting hole (102) satisfies: 0.2d1≤d2≤0.7d1, 0.3d4≤d1≤0.8d4, where d1 is the diameter of the circular opening of the groove or the diagonal length of the rectangular opening, d2 is the diameter of the circular bottom of the groove or the diagonal length of the rectangular bottom, and d4 is the diameter of the second sub-pillar (1222); the depth of the riveting hole (102) is H4,H3-0.2mm≤H4≤H3+0.8mm.

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