Current collecting plate and battery
By setting a protrusion on the circumferential edge of the through hole of the current collector, the electrode tab is welded to the protrusion, which solves the problem of small welding area in traditional methods, improves the current carrying capacity of the battery and reduces internal resistance.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- HUIZHOU EVE POWER CO LTD
- Filing Date
- 2025-01-24
- Publication Date
- 2026-06-18
AI Technical Summary
The traditional full-tab flattening design results in a small welding area when welding the current collector and the tabs, leading to poor battery overcurrent capacity and high internal resistance.
The main body of the collector plate has a through hole, and the circumferential edge has a protrusion. The electrode tab passes through the through hole and is welded to the protrusion to increase the welding area.
The effective welding area between the current collector and the tabs was increased, enhancing the battery's current carrying capacity and reducing internal resistance.
Smart Images
Figure CN2025074844_18062026_PF_FP_ABST
Abstract
Description
A current collector and battery
[0001] This application claims priority to Chinese Patent Application No. 2024118366143, filed on December 12, 2024, and Chinese Patent Application No. 2024230794945, filed on December 12, 2024, the entire contents of which are incorporated herein by reference. Technical Field
[0002] This application relates to the field of battery technology, and in particular to a current collector and a battery. Background Technology
[0003] As the size and capacity of cylindrical batteries continue to increase, traditional tab lead-out methods can no longer meet the current requirements of large cylindrical batteries. Currently, to meet the current carrying capacity of the cells and improve the rate performance of cylindrical batteries, most cylindrical battery cells adopt a full-tab flattening design. Specifically, after the cell is manufactured, the positive and negative tabs at both ends of the cell are flattened. Then, positive and negative current collectors are welded to the tabs at both ends of the cell, and finally, the cell is encapsulated to form a battery. The full-tab cylindrical battery flattening method in related technologies combines the originally upright tabs, maximizing the contact between the tabs for better current collection. Furthermore, the direct lead-out of the entire battery through all tabs effectively reduces internal resistance. Simultaneously, flattening all tabs onto the same plane facilitates subsequent current collector welding and ensures effective current conduction. Technical issues
[0004] When flattening the tabs and welding them to the current collector, laser intermittent spot welding and / or laser continuous line welding are generally used. These two welding methods result in a small effective welding area between the current collector and the tabs, leading to poor current carrying capacity and high internal resistance of the battery. Technical solutions
[0005] Firstly, this application provides a data collection disk, comprising:
[0006] The main body has a through hole located on the outer side of the axis of the main body.
[0007] The protrusion is provided on one surface of the main body and is located at the circumferential edge of the through hole.
[0008] Secondly, this application provides a battery, including: a battery cell, a tab portion and the aforementioned current collector, wherein the tab portion is disposed at both axial ends of the battery cell, and a surface of the tab portion facing away from the battery cell is welded to the body portion of the current collector.
[0009] The electrode portion has a tab protruding from the back of the battery cell. The tab is provided corresponding to the protrusion and passes through the through hole and is welded to the protrusion. Beneficial effects
[0010] The current collector has a through hole in its main body, and a protrusion is formed on one surface of the main body relative to the circumferential edge of the through hole. When the current collector is applied to a battery, it is positioned on the side of the tab that is away from the cell. The main body of the current collector is welded to the tab, and the tab can pass through the through hole to be welded to the protrusion. Thus, based on the welding of the main body and tab in related technologies, this application utilizes the welding of the tab to the protrusion, greatly increasing the effective welding area between the current collector and the tab, thereby improving the battery's current carrying capacity and reducing its internal resistance. Attached Figure Description
[0011] Figure 1 is a schematic diagram of the battery structure of this application;
[0012] Figure 2 is a top view of the battery of this application;
[0013] Figure 3 is a front view of the battery of this application;
[0014] Figure 4 is an exploded view of the battery of this application;
[0015] Figure 5 is a top view of the current collector of this application;
[0016] Figure 6 is a process flow diagram of welding the electrode tab and the protrusion in this application;
[0017] Figure 7 is a schematic diagram of the welding structure between the electrode tab and the collector plate in this application.
[0018] Figure label:
[0019] 1. Current collector; 11. Body; 111. Internal area; 112. External area; 113. Center hole; 12. Through hole; 13. Protrusion; 14. Notch; 15. Connecting piece; 2. Battery cell; 3. Electrode; 31. Electrode; 311. Electrode unit; 32. Through hole. Embodiments of the present invention
[0020] Example 1
[0021] Referring to Figures 4 and 5, this embodiment provides a collector plate, including a body portion 11 and a protrusion 13. The body portion 11 has a through hole 12, which is located on the outer side of the axis of the body portion 11. The protrusion 13 protrudes from a surface of the body portion 11 and is located at the circumferential edge of the through hole 12.
[0022] This embodiment uses a circular current collector as an example. In actual applications, the current collector can also be square or other shapes; only structural adjustments are needed. This current collector is used in cylindrical batteries. Therefore, the main body 11 of the current collector is circular. The main body 11 is used to correspond to the tab end of the battery cell 2. The main body 11 has two opposing surfaces. One surface of the main body 11 is used for the protrusion 13 to extend, and the other surface of the main body 11 faces the tab end of the battery cell 2 to facilitate welding to the tab end. A through hole 12 penetrates the two opposing surfaces of the main body 11 to facilitate the tab 31 of the tab end passing through the through hole 12. The protrusion 13 is located at the circumferential edge of the through hole 12, so that after the tab 31 passes through the through hole 12, the side of the tab 31 can fit tightly against the side of the protrusion 13 to facilitate welding between the tab 31 and the protrusion 13.
[0023] It should be noted that the through hole 12 can be an arc-shaped structure, a square structure, a triangular structure, an irregular structure, etc. Its circumferential edge includes any position of the entire outer periphery of the through hole 12. Taking the arc-shaped structure in Figure 5 as an example, the circumferential edge can be the outer arc ring, the inner arc ring, or the radial edge used to connect the outer arc ring and the inner arc ring of the through hole 12. The protrusion 13 can be set at any position of the outer arc ring, the inner arc ring, or the radial edge, as long as its position corresponds to the position of the electrode 31, so as to facilitate the electrode 31 and the protrusion 13 to fit and weld together.
[0024] Therefore, it can be seen that the main body 11 of the current collector 1 has a through hole 12, and the circumferential edge of the through hole 12 has a protrusion 13 protruding from one surface of the main body 11. When the current collector 1 is applied to a cylindrical battery, the current collector 1 is correspondingly located on the side of the tab end away from the cell 2. The main body 11 of the current collector 1 is welded to the tab end, and the tab 31 can pass through the through hole 12 to be welded to the protrusion 13. In this way, this embodiment can not only realize the welding of the tab end to the main body 11, but also increase the welding of the tab 31 to the protrusion 13, thereby greatly increasing the effective welding area between the current collector 1 and the tab end, thereby improving the current carrying capacity of the cylindrical battery and reducing the internal resistance of the cylindrical battery.
[0025] It should be noted that the collector plate 1 has a through-hole 113 on its axis. The through-hole 12 and the protrusion 13 are both spaced apart from the center hole 113. That is, the through-hole 12 is not located at the center hole 113, and there is also a gap between the circumferential edge of the through-hole 12 and the center hole 113, so that the protrusion 13 is not located at the edge of the center hole 113, so as to avoid the winding needle used for winding the battery cell 2 in the center hole 113, and to facilitate liquid injection, air venting, etc.
[0026] In some embodiments, the body portion 11 includes an inner region 111 and an outer region 112 coaxially arranged, the outer region 112 surrounding the periphery of the inner region 111, and a through hole 12 is formed between the outer region 112 and the inner region 111, and a protrusion 13 is provided on the circumferential edge of the inner region 111. A central hole 113 is provided at the axis of the inner region 111.
[0027] The inner region 111 and the outer region 112 are connected by a connecting area. Except for the connecting area, the inner region 111 and the outer region 112 are connected by through holes 12, thereby reducing the mass of the current collector 1 while ensuring its integrity. Theoretically, protrusions 13 can be provided at various parts of the circumferential edge of the through hole 12, namely the outer arc, the inner arc, and the radial edge. However, considering the reliability of the connection between the current collector 1 and the electrode end and the efficiency of current transmission, the protrusions 13 are provided at the circumferential edge of the inner region 111, that is, at the radial inner arc edge of the through hole 12.
[0028] In some embodiments, the protrusion 13 is obtained by stamping and folding or stamping and cutting the body portion 11, forming an inner region 111, an outer region 112, and a through hole 12. The appropriate position of the body portion 11 of the current collector 1 is stamped using a stamping device, then the stamped area is adaptively cut, and then folded relative to one surface of the body portion 11, thereby forming the protrusion 13 on one surface of the body portion 11 and forming a through hole 12 at the stamped position. Simultaneously, the through hole 12 divides the body portion 11 into the inner region 111 and the outer region 112. On the one hand, the stamping and cutting forming process is simple and convenient to operate; on the other hand, the protrusion 13 and the body portion 11 are an integral structure, which is beneficial to improving the current carrying capacity of the battery.
[0029] In some embodiments, there may be one or more protrusions 13. In this embodiment, there are two protrusions 13, which protrude from the same surface of the body portion 11, and both protrusions 13 are located at the circumferential edge of the through hole 12.
[0030] In some embodiments, the protrusion 13 is stamped, cut, and folded into two parts. Both protrusions 13 are located on the circumferential edge of the inner region 111. The curvature of the two protrusions 13 is relatively small, making it less prone to overlapping and wrinkling due to the curved structure during folding. This ensures the flatness of the sides of the protrusions 13, which is beneficial for the flatness and firmness of welding with the electrode lug 31. Furthermore, the relatively small number of protrusions 13 greatly reduces the difficulty of stamping and cutting, thereby effectively reducing costs.
[0031] Both protrusions 13 are located at the radial inner arc edge of the through hole 12, and the two protrusions 13 are arranged radially symmetrically. The radial symmetrical arrangement of the two protrusions 13 helps to improve the stability of the connection between the current collector 1 and the electrode end after the protrusions 13 are welded to the electrode tab 31.
[0032] In some embodiments, two protrusions 13 are spaced apart, and a notch 14 is provided between the two protrusions 13. The notch 14 is connected to the through hole 12 as an integral structure. The two protrusions 13 are arranged spaced apart on the basis of radial symmetry, which helps to reduce the curvature of the protrusions 13, thereby improving the flatness of the side surface of the protrusions 13 and thus improving the flatness and firmness of the welding between the protrusions 13 and the electrode lug 31.
[0033] Theoretically, the two protrusions 13 could be obtained by stamping, cutting, and folding twice, but this would significantly increase the complexity of the forming process and raise costs. Therefore, in this embodiment, a continuous through hole 12 is obtained by stamping once, and the stamping area is correspondingly cut and folded into two spaced and radially symmetrical protrusions 13, thereby forming a cut notch 14 between the two protrusions 13. The notch 14 is connected to the through hole 12 as an integral structure, which can greatly simplify the forming process and reduce costs.
[0034] In some embodiments, the central angle of the notch 14 is 30°-60°, and the central angle of the protrusion 13 is 75°-105°. The matching of the central angles of the notch 14 and the protrusion 13 ensures that the two radially symmetrical protrusions 13 have a small curvature, thus preventing the accumulation of more wrinkles when the multi-layered tabs 31 are bent and welded to the corresponding protrusions 13, thereby avoiding an increase in the stacking thickness and ensuring the welding strength between the tabs 31 and the protrusions 13.
[0035] In addition to the other surface of the current collector 1 being welded to the tab end, the current collector 1 is also fixedly connected to the terminal post of the battery cover. In some embodiments, referring to FIG7, a connecting piece 15 is provided on the circumferential edge of the body portion 11. The connecting piece 15 can be bent away from the body portion 11 relative to one surface of the body portion 11 so that the protrusion 13 is located between the connecting piece 15 and the body portion 11.
[0036] The connecting piece 15 is located on the circumferential edge of the body portion 11. It can be bent into a "Z" shape relative to one surface of the body portion 11 or directly folded to be welded to the terminal post, thereby realizing the electrical connection between the battery cell 2 and the terminal post. After being bent, the connecting piece 15 is located above the protrusion 13, thereby using the connecting piece 15 to separate the protrusion 13 from the battery cover plate to avoid affecting the structural stability of the protrusion 13.
[0037] In some embodiments, the central angle of the inner region 111 is 360°, and the central angle of the outer region 112 is 210°-240°, forming an opening on the periphery of the inner region 111. The connecting piece 15 is disposed at the opening and connects with both the inner region 111 and the outer region 112. The outer region 112 is configured with an arc-shaped structure, thereby providing an opening for the installation of the connecting piece 15, allowing the connecting piece 15 to extend outward from the edge of the inner region 111. Thus, when the connecting piece 15 is bent into a "Z" shape or folded directly, it ensures that the connecting piece 15 is stably positioned between the body 11 and the electrode post, thereby improving the weld strength between the connecting piece 15 and the electrode post. Simultaneously, the central angle of 210°-240° ensures that the outer region 112 has a sufficiently large area for welding, thereby facilitating an increase in the current carrying capacity of the cylindrical battery and reducing the internal resistance of the cylindrical battery.
[0038] Example 2
[0039] Referring to Figures 1-3, this embodiment provides a cylindrical battery, including: a cell 2, tabs 3, and a current collector 1 as described in Embodiment 1. The tabs 3 are located at both axial ends of the cell 2, and one surface of the tabs 3 facing away from the cell 2 is welded to the body 11 of the current collector 1. Tabs 31 protrude from the tabs 3 facing away from the cell 2, corresponding to protrusions 13. The tabs 31 pass through a through hole 12 and are welded to the protrusions 13.
[0040] The two ends of the battery cell 2 are the positive and negative terminals, respectively, and each is provided with a positive terminal lug and a negative terminal lug. Both the positive and negative terminal lugs are connected to a current collector 1. In this embodiment, the current collector 1 corresponding to the positive and negative terminal lugs has the same structure, so there is no distinction between positive and negative, and they are uniformly represented by the terminal lug 3.
[0041] During cylindrical battery assembly, the cell 2 and the tabs 3 at both axial ends of the cell 2 are formed by winding. The axis of the cell 2 and the axis of the tabs 3 are respectively provided with channels and through holes 32 to accommodate winding needles and for functions such as electrolyte injection and venting. The channels, through holes 32, and the center hole 113 of the current collector 1 are correspondingly arranged and located on the same axis. The end face of the tab 3 facing away from the cell 2 is welded to the body 11. The tab 31 can pass through the through hole 12 so that the side of the tab 31 fits and welds to the corresponding side of the protrusion 13, thereby achieving welding between the tab 3 and the current collector 1. After the above assembly is installed in the casing, the connecting piece 15 of the current collector 1 is bent to weld the terminals of the battery cover plate. Then, the battery cover plate is sealed to the end of the casing, thus completing the assembly of the cylindrical battery. Electrical connection between the terminals and the cell 2 can be achieved through the current collector 1.
[0042] Thus, in this embodiment, the tab 3 of the cylindrical battery is not only welded to the body 11 at its end face, but also welded to the protrusion 13 by means of tab 31, which greatly increases the effective welding area between the current collector 1 and the tab 3, thereby improving the current carrying capacity of the cylindrical battery and reducing the internal resistance of the cylindrical battery. Furthermore, when the connecting piece 15 is bent and welded to the terminal post, it can avoid welding the protrusion 13 to the tab 31, thereby improving the strength of the weld between the protrusion 13 and the tab 31.
[0043] In this embodiment, referring to Figure 7, the body portion 11 and the tab portion 3 are connected by spot welding or wire welding, and the tab 31 and the protrusion 13 are connected by contact welding. The body portion 11 and the tab portion 3 can be welded using existing spot welding or wire welding methods to achieve electrical connection between the body portion 11 and the tab portion 3. Since the tab 31 and the protrusion 13 are in close contact, they are welded by contact welding so that the corresponding sides of the tab 31 and the protrusion 13 are welded as a whole. This not only increases the welding area, improves the strength of the connection between the two, improves the current carrying capacity, and reduces the internal resistance, but also ensures that the contact welding between the tab 31 and the protrusion 13 does not affect the body portion 11 and the tab 3, thus preventing incomplete welding or burn-through, which is beneficial to improving welding efficiency and yield.
[0044] Generally, the tab 31 can be attached to one side of the protrusion 13. In some embodiments, referring to FIG6, the tab 31 is bent to form an "n" shaped structure, and the tab 31 is attached to the two opposite surfaces of the protrusion 13.
[0045] In some embodiments, the tab 31 includes at least two tab units 311. Multiple tab units 311 are die-cut, overlapped, and compacted to form the tab 31. The tab 31 passes through the through hole 12 and is attached to one side of the protrusion 13, then bent and attached to the other side of the protrusion 13. Thus, the tab 31 is semi-enclosed and attached to the side of the protrusion 13. Welding the tab 31 to the protrusion 13 improves the strength of the connection between the two.
[0046] Each tab 31 includes at least two tab units 311, which helps to reduce the number of tabs 31 and protrusions 13, reduce molding costs, and increase the thickness of the connection between the tab 31 and the protrusions 13, which helps to improve flow capacity.
[0047] In some embodiments, there are two tabs 31, and the number of protrusions 13 is equal to the number of tabs 31 and their positions correspond one-to-one. Both tabs 31 pass through the through hole 12 and are welded to the corresponding two protrusions 13.
[0048] The protrusion 13 is stamped, cut, and folded into two parts. Both protrusions 13 are located on the circumferential edge of the inner area 111. The curvature of the two protrusions 13 is relatively small, making it less prone to overlapping and wrinkling during folding due to their curved structure, thus ensuring the flatness of the sides of the protrusions 13. A tab 31 is provided corresponding to the protrusion 13. Correspondingly, the tab 31 has a smaller curvature. After passing through the through hole 12, the tab 31 is less likely to overlap or wrinkle when fitting and bending with the sides of the protrusion 13, which helps improve the flatness and strength of the welding between the protrusion 13 and the tab 31. Furthermore, the relatively small number of two protrusions 13 greatly reduces the difficulty of stamping and cutting, thereby effectively reducing costs. The relatively small number of two tabs 31 also helps reduce die-cutting and compaction costs and simplifies the process.
[0049] In some embodiments, the two tabs 31 are spaced apart and radially symmetrical. Correspondingly, the two protrusions 13 are spaced apart and radially symmetrical. The spaced-apart arrangement of the two protrusions 13 and the two tabs 31 on a radially symmetrical basis helps to reduce the curvature of the protrusions 13 and the tabs 31, thereby improving the flatness of the sides of the protrusions 13 and the tabs 31, and thus improving the flatness and firmness of the weld between the protrusions 13 and the tabs 31.
Claims
1. A collector disk, comprising: The body part (11) has a through hole (12) which is located on the outer side of the axis of the body part (11). A protrusion (13) is provided on a surface of the body part (11) and the protrusion (13) is located at the circumferential edge of the through hole (12).
2. The collector disk according to claim 1, wherein: The body part (11) includes an inner area (111) and an outer area (112) arranged coaxially. The outer area (112) surrounds the periphery of the inner area (111), and the through hole (12) is formed between the outer area (112) and the inner area (111). The protrusion (13) is provided on the circumferential edge of the inner area (111).
3. The collector disk according to claim 2, wherein: The protrusion (13) is obtained by stamping and folding or stamping and cutting the body part (11) to form the inner area (111), the outer area (112) and the through hole (12).
4. The collector disk according to any one of claims 1-3, wherein: The protrusion (13) is provided in two parts, and the two protrusions (13) protrude from the same surface of the body part (11), and both protrusions (13) are located at the circumferential edge of the through hole (12).
5. The collector disk according to claim 4, wherein: Both protrusions (13) are located at the radial inner arc edge of the through hole (12), and the two protrusions (13) are arranged radially symmetrically.
6. The collector disk according to claim 5, wherein: The two protrusions (13) are spaced apart, and a notch (14) is provided between the two protrusions (13). The notch (14) and the through hole (12) are connected to form an integral structure.
7. The collector disk according to claim 6, wherein: The central angle of the notch (14) is 30°-60°, and the central angle of the protrusion (13) is 75°-105°.
8. The collector disk according to claim 2 or 3, wherein: The circumferential edge of the body part (11) is provided with a connecting piece (15), which can be bent away from the body part (11) relative to a surface of the body part (11) so that the protrusion (13) is located between the connecting piece (15) and the body part (11).
9. The collector disk according to claim 8, wherein: The inner area (111) has a center angle of 360° and the outer area (112) has a center angle of 210°-240°, so as to form an opening on the periphery of the inner area (111). The connecting piece (15) is provided at the opening and is connected to the inner area (111) and the outer area (112).
10. A battery, comprising: The battery cell (2), the tab (3) and the current collector (1) according to any one of claims 1-9, wherein the tab (3) is provided at both ends of the battery cell (2) along the axial direction, and the surface of the tab (3) facing away from the battery cell (2) is welded to the body part (11) of the current collector (1); The tab (3) has a tab (31) protruding from the battery cell (2). The tab (31) is provided corresponding to the protrusion (13). The tab (31) passes through the through hole (12) and is welded to the protrusion (13).
11. The battery according to claim 10, wherein: The tab (31) is bent to form an "n" shaped structure, and the tab (31) is attached to the opposite two surfaces of the protrusion (13).
12. A battery according to claim 10, wherein: The main body (11) and the tab (3) are connected by spot welding or wire welding, and the tab (31) and the protrusion (13) are connected by contact welding.
13. The battery according to any one of claims 10-12, wherein: The electrode tab (31) is provided in two parts. The number of protrusions (13) is equal to the number of electrode tabs (31) and their positions correspond one-to-one. Both electrode tabs (31) pass through the through hole (12) and are welded to the corresponding two protrusions (13).
14. The battery according to claim 12, wherein: The two electrodes (31) are spaced apart and are radially symmetrical.