Current collector, electrode assembly and battery pack
By designing a bending section in the current collector to absorb and release impact energy, the problem of insufficient strength of the current collector is solved, and the stability and safety of the battery are improved.
Patent Information
- Application Number
- CN202422558425.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-10-22
AI Technical Summary
Existing current collectors have low strength and are prone to breakage during use, leading to battery failure.
A current collector is designed, including a pole section, a lug section and a bending section. The two ends of the bending section at least partially overlap the projections of the pole section onto the plane, forming a gap that allows for displacement, absorbing and releasing impact energy, and preventing breakage.
By absorbing and releasing energy through the elastic deformation of the bending section, the current collector is prevented from breaking under axial impact, thus improving the stability and safety of the battery.
Smart Images
Figure CN223539842U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, specifically to a current collector, electrode assembly, and battery pack. Background Technology
[0002] A battery is a device that converts chemical energy into electrical energy. It typically includes a core, terminals, and current collectors. The tabs of the core are electrically connected to the terminals through the current collectors, so that the battery can supply power to external electrical devices through the terminals.
[0003] In related technologies, current collectors have low strength, making them prone to breakage during use, which can lead to battery malfunction.
[0004] Therefore, existing technologies need to be improved and enhanced. Utility Model Content
[0005] Embodiments of this application provide a current collector, electrode assembly, and battery pack that can improve the technical problem of low strength in existing current collectors.
[0006] In a first aspect, embodiments of this application provide a current collector, which includes:
[0007] A tab section is disposed on one side of the electrode post section, and the tab section is used for electrical connection with the tab.
[0008] The first bending segment bends and connects the pole post segment and the tab segment, and the two ends of the first bending segment at least partially overlap the projections of the pole post segment onto the plane in which the pole post segment is located.
[0009] In some embodiments, the current collector further includes a second bent section, which is bent and connected between the tab section and the first bent section, and the two ends of the second bent section at least partially overlap in the projection of the plane where the pole section is located.
[0010] In some embodiments, the current collector further includes a first extension section, the first extension section including a first side and a second side connected to each other, the first side connecting to the first bend section, the second side connecting to the second bend section, and the projection of the first extension section onto the plane of the pole section partially coinciding with the pole section.
[0011] In some embodiments, the current collector further includes a second extension section, the second extension section including a third side and a fourth side connected to each other, the third side connecting to the second bend section, the fourth side connecting to the tab section, and the projection of the second extension section onto the plane of the pole section partially coinciding with the pole section.
[0012] In some embodiments, the first extension segment is arranged parallel to the pole segment;
[0013] The second extension section is arranged parallel to the pole section.
[0014] In some embodiments, the pole segment includes a short side connected to the first bent segment and a long side perpendicular to the short side, the angle between the long side and the second side being between 30° and 60°; and / or,
[0015] The angle between the third side and the fourth side is between 30° and 60°.
[0016] In some embodiments, the tab section includes a welded portion and a clearance portion, the clearance portion being connected to the second extension section, the welded portion being connected to one end of the clearance portion away from the second extension section, and the clearance portion forming a clearance space for avoiding the core package.
[0017] In some embodiments, the clearance portion includes a first connecting section and a second connecting section, the first connecting section being parallel to the welded portion, the second connecting section being connected to the welded portion, and the second connecting section and the second extension section protruding from the same side of the first connecting section to form the clearance space.
[0018] In some embodiments, the widths of the first bend segment and the second bend segment are smaller than the widths of the pole segment and the tab segment.
[0019] In some embodiments, the tab segment includes an end portion away from the pole post segment, the end portion including a first arc portion and a second arc portion disposed opposite to each other along the width direction of the tab segment, the first arc portion being located on the side of the second arc portion facing the core package, and the arc radius of the first arc portion being greater than the arc radius of the second arc portion.
[0020] In some embodiments, the pole section is provided with a through hole, and the through hole extends through the pole section along a first direction;
[0021] The pole post section is further provided with a first annular groove; the first annular groove is provided on the side of the pole post section away from the tab section and surrounds the through hole; and / or;
[0022] The pole post section is also provided with a second annular groove; the second annular groove is provided on the side of the pole post section near the tab section and surrounds the through hole.
[0023] Secondly, this application provides an electrode assembly, comprising:
[0024] Core package, including tabs and poles;
[0025] Top cover, connected to the pole post;
[0026] As described above, the current collector is installed on the top cover, the pole section is electrically connected to the pole, and the tab section is electrically connected to the tab.
[0027] Thirdly, this application provides a battery pack, comprising:
[0028] The housing has a mounting cavity;
[0029] As described above, the electrode assembly has the core package and the current collector disposed within the mounting cavity, and the top cover is disposed on the housing to close the mounting cavity.
[0030] The beneficial effects of the embodiments of this application are as follows:
[0031] This application provides a current collector comprising a terminal section, a tab section, and a first bent section. The terminal section is used for electrical connection with a terminal, and the tab section is disposed on one side of the terminal section for electrical connection with the tab. The first bent section is bent and connected between the terminal section and the tab section, and the two ends of the first bent section at least partially overlap in projection onto the plane of the terminal section. In the prior art, the tab section of current collectors is mostly a straight structure with only a rounded transition to the terminal section. When subjected to a large axial impact force, the impact force is entirely applied to the rounded transition. When the force exceeds the bearing capacity, the deformation cannot be recovered, and breakage is likely to occur. In this application, the two ends of the first bent section at least partially overlap in projection onto the plane of the terminal section, the bending arc is larger, and a gap for displacement is formed between the two ends of the first bent section. When subjected to axial impact, the first bending section, connected to the tab section, undergoes elastic deformation from one end to the other, converting the kinetic energy of the impacting current collector into elastic potential energy. During the energy conversion process, the first bending section can absorb and release this energy, causing the vibration of the current collector to gradually decrease, thus avoiding the problem of current collector breakage during battery use or vibration testing. Attached Figure Description
[0032] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0033] Figure 1 This is a schematic diagram of the structure of the current collector provided in the embodiments of this application. Figure 1 ;
[0034] Figure 2 This is a schematic diagram of the structure of the current collector provided in the embodiments of this application. Figure 2 ;
[0035] Figure 3This is a schematic diagram of the structure of the current collector provided in the embodiments of this application. Figure 3 ;
[0036] Figure 4 yes Figure 1 A plan view of the current collector without bending.
[0037] Figure 5 yes Figure 1 A schematic diagram of the first bend of the folded section of the current collector shown;
[0038] Figure 6 yes Figure 1 A schematic diagram of the second bend of the folded section of the current collector shown;
[0039] Figure 7 yes Figure 1 A schematic diagram of the third bend of the folded section of the current collector shown;
[0040] Figure 8 yes Figure 1 A schematic diagram of the first bend of the clearance section of the current collector shown;
[0041] Figure 9 yes Figure 1 A schematic diagram of the second bend in the clearance section of the current collector shown;
[0042] Figure 10 yes Figure 1 Top view of the manifold shown Figure 1 ;
[0043] Figure 11 yes Figure 10 Schematic cross-section of the current collector along AA Figure 1 ;
[0044] Figure 12 yes Figure 11 An enlarged schematic diagram of part A of the current collector shown;
[0045] Figure 13 yes Figure 10 Schematic cross-section of the current collector along AA Figure 2 ;
[0046] Figure 14 yes Figure 13 An enlarged schematic diagram of part B of the current collector shown;
[0047] Figure 15 yes Figure 10 Schematic cross-section of the current collector along AA Figure 3 ;
[0048] Figure 16 yes Figure 15 An enlarged schematic diagram of part C of the current collector shown;
[0049] Figure 17 yes Figure 10 Schematic cross-section of the current collector along AA Figure 4 ;
[0050] Figure 18 yes Figure 17 An enlarged schematic diagram of part D of the current collector shown;
[0051] Figure 19 This is a schematic diagram of the structure of the electrode assembly provided in the embodiments of this application;
[0052] Figure 20 This is a side view of the electrode assembly provided in an embodiment of this application.
[0053] Figure label:
[0054] 100. Current collector;
[0055] 10. Pole post section; 101. Long side; 11. Through hole; 111. First annular groove; 112. Second annular groove;
[0056] 20. Pole tab section; 21. Welded part; 211. End; 2111. First arc section; 2112. Second arc section; 22. Clearance section; 220. Clearance space; 221. First connecting section; 222. Second connecting section;
[0057] 31. First bend; 32. Second bend; 33. First extension; 331. First side; 332. Second side; 34. Second extension; 341. Third side; 342. Fourth side; 35. Notch;
[0058] 200. Electrode assembly; 2001. Top cover; 202. Electrode post; 203. Electrode tab; 204. Core package. Detailed Implementation
[0059] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a portion of the embodiments, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or working state, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.
[0060] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the current collector provided in an embodiment of this application. This application provides a current collector 100, which is applied to an electrode assembly 200. The current collector 100 includes a terminal section 10 and a tab section 20. The terminal section 10 is used for electrical connection with a terminal 202. The tab section 20 is disposed on one side of the terminal section 10 and is used for electrical connection with a tab 203. A first bent section 31 is bent and connected between the terminal section 10 and the tab section 20. The two ends of the first bent section 31 at least partially overlap in projection onto the plane of the terminal section 10. The bent first bent section 31 is located below the terminal section 10 along the direction of gravity, and the two ends of the first bent section 31 can be one end closer to the terminal section 10 along the direction of gravity and the other end farther away from the terminal section 10 along the direction of gravity.
[0061] In existing technologies, the tab section of the current collector 100 is mostly a straight structure, with only a rounded transition to the terminal section. When subjected to a large axial impact force, since the impact force acts entirely at the rounded transition, the deformation cannot be recovered when the force exceeds the bearing capacity, easily leading to breakage. In this application, the two ends of the first bending section 31 at least partially overlap the projections on the plane of the terminal section 10, with a larger bending arc, and a gap for displacement is formed between the two ends of the first bending section 31, forming an overall C-shaped structure. When subjected to an axial impact, the end of the first bending section 31 connected to the tab section 20 undergoes elastic deformation to the other end, converting the kinetic energy of the impact on the current collector 100 into elastic potential energy. The first bending section 31 can absorb this energy, causing the vibration of the current collector 100 to gradually decay, avoiding the problem of the current collector 100 breaking during battery use or vibration testing.
[0062] Please refer to Figures 2-3 , Figure 2 This is a schematic diagram of the structure of the current collector provided in the embodiments of this application. Figure 2 , Figure 3 This is a schematic diagram of the structure of the current collector provided in the embodiments of this application. Figure 3 In some embodiments, the current collector 100 further includes a second bent section 32, which is bent and connected between the tab section 20 and the first bent section 31. The two ends of the second bent section 32 at least partially overlap in projection onto the plane of the pole section 10. It is understood that since the second bent section 32 is connected to the first bent section 31, when the first bent section 31 undergoes elastic deformation, the second bent section 32 will also undergo elastic deformation under the influence of the first bent section 31. The multi-layered bending structure can further increase the elastic deformation, reduce the impact of forces in the height direction, and thus avoid deformation or breakage caused by excessive local stress.
[0063] In some embodiments, the current collector 100 further includes a first extension section 33, the first extension section 33 including a first side 331 and a second side 332, the first side 331 connecting to the first bent section 31, the second side 332 connecting to the second bent section 32, and the projection of the first extension section 33 onto the plane where the pole section 10 is located partially coincides with the pole section 10.
[0064] The current collector 100 further includes a second extension section 34, which includes a third side 341 and a fourth side 342. The third side 341 is connected to the second bending section 32, and the fourth side 342 is connected to the tab section 20. The projection of the second extension section 34 onto the plane where the pole section 10 is located partially coincides with the pole section 10.
[0065] Understandably, when the tab segment 20 is subjected to an external force perpendicular to the second extension segment 34, if the external force is perpendicular to the axis, the second extension segment 34 will bend and rotate away from the tab segment 20 by a certain angle. The displacement of the second extension segment 34 perpendicular to the axis is the rotation angle multiplied by the length of the second extension segment 34. As the length of the second extension segment 34 increases, its elastic deformation increases, enabling it to convert more kinetic energy into elastic potential energy. Similarly, as the length of the first extension segment 33 increases, its elastic deformation also increases.
[0066] Specifically, the first bending segment 31 can be a first curved surface, the second bending segment 32 can be a second curved surface, one end of the first extension segment 33 is connected to the first curved surface and the other end is connected to the second curved surface, and one end of the second extension segment 34 is connected to the second curved surface and the other end is connected to the tab segment 20.
[0067] In some embodiments, the first extension segment 33 is arranged parallel to the pole post segment 10, and the second extension segment 34 is arranged parallel to the pole post segment 10. Specifically, since the first extension segment 33 and the second extension segment 34 are located at the top of the core package 204, the parallel structure can increase structural consistency and avoid the increased installation difficulty caused by tilted or misaligned structures.
[0068] Please refer to Figure 4 , Figure 4 yes Figure 1 The diagram shows a planar view of the current collector without bending. In some embodiments, the current collector 100 is a single plane, meaning the tab section 20 and the post section 10 are on the same plane. The strip-shaped current collector 100 is shaped by bending it three times. Please refer to... Figures 5-7 , Figure 5 yes Figure 1 The diagram shows the first bend of the folded section of the current collector. Figure 6 yes Figure 1 The diagram shows the second bend of the folded section of the current collector. Figure 7 yes Figure 1 The diagram shows the third bend of the folded section of the current collector. The first bend is a 180° bend, and the third bend is a 90° bend. The pole column section 10 includes a short side connected to the first bend section 31 and a long side 101 perpendicular to the short side. The bend line of the first bend is perpendicular to the long side 101, and the bend line of the third bend is perpendicular to the short side. The bend line of the second bend can be between 30° and 60° with the long side 101 of the pole lug section 20. After the three bends, the pole lug section 20 is bent again to form an arched clearance section 22 structure.
[0069] In some embodiments, the second bent segment 32 includes a third side 341 connected to the second extended segment 34, and the pole post segment 10 includes a long side 101 disposed opposite to each other. The angle between the second side 332 and the long side 101 is between 30° and 60°; the angle between the third side 341 and the fourth side 342 is between 30° and 60°. Specifically, since the fourth side 342 of the pole tab segment 20 is parallel to the long side 101 of the pole post segment 10 after the third bend, the second side 332 can form an angle α between 30° and 60° with the long side 101, and the third side 341 can form an angle β between 30° and 60° with the fourth side 342, with the two angles being the same size. The angles can be 30°, 40°, 45°, 50°, 60°, etc., and are not limited herein.
[0070] In some embodiments, the pole segment 10 includes a long side 101 disposed opposite to each other, and the included angle α between the second side 332 and the long side 101 is between 30° and 60°; or the included angle β between the third side 341 and the fourth side 342 is between 30° and 60°.
[0071] Specifically, since the fourth side 342 of the tab segment 20 and the long side 101 of the pole segment 10 may shift after the third bend, the second side 332 can form an angle α between 30° and 60° with the long side 101, and the third side 341 can form an angle β between 30° and 60° with the fourth side 342. The angle can be 30°, 40°, 45°, 50°, 60°, etc., and this application does not limit it.
[0072] Please combine Figure 2 refer to Figures 8-9 , Figure 8 yes Figure 1 The diagram shows the first bend of the clearance section of the current collector. Figure 9 yes Figure 1The diagram shows the second bending of the clearance portion of the current collector. In some embodiments, the tab section 20 includes a welding portion 21 and a clearance portion 22. The clearance portion 22 is connected to the second extension section 34, and the welding portion 21 is connected to the end of the clearance portion 22 away from the second extension section 34. The clearance portion 22 forms a clearance space 220 for avoiding the electrode assembly 200.
[0073] In some embodiments, the clearance portion 22 includes a first connecting section 221 and a second connecting section 222. The first connecting section 221 is parallel to the welding portion 21, and the second connecting section 222 is connected to the welding portion 21. The second connecting section 222 and the second extension section 34 protrude from the same side of the first connecting section 221 to form the clearance space 220. Specifically, the first connecting section 221 is parallel to the tab section 20 and is located on the side of the pole post section 10 away from the core package 204. One end of the second connecting section 222 is connected to the first connecting section 221, and the other end is inclined and connected to the tab section 20 to adapt to the shape of the tab 203.
[0074] In some embodiments, the widths of the first bent segment 31 and the second bent segment 32 are smaller than the widths of the pole post segment 10 and the tab segment 20. Specifically, as Figure 4 As shown, a notch 35 is provided at the edge of the current collector 100 corresponding to the first bending segment 31 and the second bending segment 32. During multiple bending processes, the sharp corners of the bending can be prevented from piercing the insulation structure of the core pack 204 or the battery, thereby improving the safety of the battery.
[0075] Please continue to refer to this. Figure 3 In some embodiments, the tab segment 20 includes an end 211 away from the pole segment 10. The end 211 includes a first arc portion 2111 and a second arc portion 2112 disposed opposite to each other along the width direction of the tab segment 20. The first arc portion 2111 is located on the side of the second arc portion 2112 facing the electrode assembly 200, and the arc radius of the first arc portion 2111 is larger than the arc radius of the second arc portion 2112.
[0076] Specifically, the first arc portion 2111 and the second arc portion 2112 are located on both sides of the end 211, respectively. The first arc angle of the first arc portion 2111 is R1, and the second arc angle of the second arc portion 2112 is R2, where R1 is greater than R2. It is understandable that having a larger first arc angle than the second arc angle prevents the welded portion 21 of the current collector 100 from approaching the side of the core package 204 and squeezing the core package 204, which could cause damage to the electrode sheet of the core package 204 and lead to an internal short circuit safety issue.
[0077] In some examples, a clearance opening can also be provided on the first arc portion 2111 of the tab section 20, or a bevel can be provided on the welding portion 21 near the core package 204. The clearance opening or bevel is used to avoid the core package 204.
[0078] Please refer to Figures 10-12 , Figure 10 yes Figure 1 Top view of the manifold shown Figure 1 , Figure 11 yes Figure 10 Schematic cross-section of the current collector along AA Figure 1 , Figure 12 yes Figure 11 The diagram shows an enlarged view of part A of the current collector. In some embodiments, the electrode post section 10 is provided with a through hole 11, which extends through the electrode post section 10 along a first direction. The through hole 11 is used to install the electrode post 202 for electrical connection. During assembly, the electrode post 202 can be inserted into the through hole 11 for installation. The through hole 11 can be used to weld structures to the electrode post 202, such as forming fusion welding, friction welding, laser welding, or ultrasonic welding; however, this embodiment does not limit the scope of the invention.
[0079] Please refer to Figures 13-14 , Figure 13 yes Figure 10 Schematic cross-section of the current collector along AA Figure 2 , Figure 14 yes Figure 13 The diagram shows an enlarged view of part B of the current collector. In some examples, the pole section 10 is also provided with a first annular groove 111. The first annular groove 111 is located at the end of the pole section 10 away from the tab section 20 and surrounds the through hole 11. Specifically, the first annular groove 111 is used to accommodate the flange of the pole 202, so that the top surface of the flange is flush with the top surface of the pole section 10, preventing the flange of the pole 202 from protruding from the structure of the pole section 10, keeping the structural surface flat, and facilitating subsequent assembly.
[0080] Please refer to Figures 15-16 , Figure 15 yes Figure 10 Schematic cross-section of the current collector along AA Figure 3 , Figure 16 yes Figure 15The diagram shows an enlarged view of a portion C of the current collector. In some examples, the pole section 10 is provided with a second annular groove 112, which is located at one end of the pole section 10 near the tab section 20 and surrounds the through hole 11. Specifically, when the flange of the pole 202 and the tab section 20 are welded, a certain protrusion is formed, which is the weld reinforcement. The weld reinforcement refers to the portion above the substrate surface formed by the accumulation and solidification of welding material during the welding process. The second annular groove 112 at the end of the pole section 10 near the tab section 20 can accommodate the weld reinforcement, preventing a shortened fatigue life at the weld and reducing the overall structural reliability.
[0081] Please refer to Figures 17-18 , Figure 17 yes Figure 10 Schematic cross-section of the current collector along AA Figure 4 , Figure 18 yes Figure 17 The diagram shows a partial enlarged view of the current collector D. In some examples, the pole section 10 is further provided with a first annular groove 111, which is located at the end of the pole section 10 away from the tab section 20 and surrounds the through hole 11. The pole section 10 is also provided with a second annular groove 112, which is located at the end of the pole section 10 close to the tab section 20 and surrounds the through hole 11.
[0082] It is understandable that by setting the first annular groove 111 and the second annular groove 112 at the same time, the flange of the pole post 202 and the upper first annular groove 111 are matched, and the second annular groove 112 leaves space for the weld reinforcement when welding the bottom, which can improve the assembly effect of the pole post 202 and the pole post section 10.
[0083] Please refer to Figures 19-20 , Figure 19 This is a schematic diagram of the structure of the electrode assembly provided in the embodiments of this application. Figure 20 This is a side view of the electrode assembly provided in an embodiment of this application. This application also provides an electrode assembly 200, which includes a core package 204, a top cover 2001, and a current collector 100. The core package 204 includes a terminal post 202 and a tab 203. The current collector 100 is as described above. The current collector 100 is mounted on the top cover 2001. The terminal post 10 is sandwiched between the core package 204 and the top cover 2001. The terminal post 202 is connected to the top cover 2001 and electrically connected to the terminal post 10. The tab 20 is electrically connected to the tab 203, thereby enabling the battery cell to perform charging and discharging functions smoothly.
[0084] This application also provides a battery pack, which includes a housing with a mounting cavity. A core pack 204 and a current collector 100 are disposed within the mounting cavity, and a top cover 2001 is connected to the housing to seal the mounting cavity. The terminal section 10 of the current collector 100 is connected to the terminal 202 of the core pack 204. Thus, power can be supplied to external devices through the terminal 202.
[0085] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A current collector applied to an electrode assembly, the electrode assembly comprising a core package, characterized in that, include: The terminal section is used for electrical connection with the terminal. A tab section is disposed on one side of the electrode post section, and the tab section is used for electrical connection with the tab. The first bending segment bends and connects the pole post segment and the tab segment, and the two ends of the first bending segment at least partially overlap the projections of the pole post segment onto the plane in which the pole post segment is located.
2. The current collector according to claim 1, characterized in that, The current collector further includes a second bending section, which bends and connects the tab section and the first bending section. The two ends of the second bending section at least partially overlap in projection onto the plane where the pole section is located.
3. The current collector according to claim 2, characterized in that, The current collector further includes a first extension section, which includes a first side and a second side that are connected to each other. The first side is connected to the first bend section, and the second side is connected to the second bend section. The projection of the first extension section onto the plane where the pole section is located partially coincides with the pole section.
4. The current collector according to claim 3, characterized in that, The current collector further includes a second extension section, which includes a third side and a fourth side connected to each other. The third side is connected to the second bending section, and the fourth side is connected to the electrode section. The projection of the second extension section onto the plane of the electrode section partially coincides with the electrode section.
5. The current collector according to claim 4, characterized in that, The first extension segment is arranged parallel to the pole section; The second extension section is arranged parallel to the pole section.
6. The current collector according to claim 4, characterized in that, The pole section includes a short side connected to the first bent section and a long side perpendicular to the short side, the angle between the long side and the second side being between 30° and 60°; and / or, The angle between the third side and the fourth side is between 30° and 60°.
7. The current collector according to claim 4, characterized in that, The tab section includes a welded portion and a clearance portion. The clearance portion is connected to the second extension section. The welded portion is connected to one end of the clearance portion away from the second extension section. The clearance portion forms a clearance space for avoiding the core package.
8. The current collector according to claim 7, characterized in that, The clearance portion includes a first connecting section and a second connecting section. The first connecting section is parallel to the welded portion, and the second connecting section is connected to the welded portion. The second connecting section and the second extension section protrude from the same side of the first connecting section to form the clearance space.
9. The current collector according to claim 2, characterized in that, The widths of the first bend segment and the second bend segment are smaller than the widths of the pole post segment and the pole lug segment.
10. The current collector according to any one of claims 1-9, characterized in that, The tab section includes an end away from the pole post section. The end includes a first arc portion and a second arc portion disposed opposite to each other along the width direction of the tab section. The first arc portion is located on the side of the second arc portion facing the core package, and the arc radius of the first arc portion is greater than the arc radius of the second arc portion.
11. The current collector according to any one of claims 1-9, characterized in that, The pole section is provided with a through hole, and the through hole extends through the pole section along a first direction; The pole post section is further provided with a first annular groove; the first annular groove is located on the side of the pole post section away from the tab section and surrounds the through hole; and / or, The pole post section is also provided with a second annular groove; the second annular groove is provided on the side of the pole post section near the tab section and surrounds the through hole.
12. An electrode assembly, characterized in that, include: Core package, including tabs and poles; Top cover, connected to the pole post; The current collector as described in any one of claims 1-11, wherein the current collector is mounted on the top cover, the pole section is electrically connected to the pole, and the tab section is electrically connected to the tab.
13. A battery pack, characterized in that, include: The housing has a mounting cavity; The electrode assembly of claim 12, wherein the core package and the current collector are disposed within the mounting cavity, and the top cover is disposed on the housing to close the mounting cavity.