Collector and battery

Abstract

The invention relates to a current collector and a battery, relating to the field of battery technology. The current collector comprises a first conductive part, which extends in the first direction, has its first surface away from the core package and is arranged in grooves on its first surface, the grooves extending in the first direction; such that the grooves divide the first conductive part into a vertical part and a weld part.

Description

Current collectors and battery cells

[0001] This application claims priority to Chinese patent applications with application numbers 202420691515.X and 202410406872.1 filed with the Patent Office of China on April 3, 2024. The entire contents of the above applications are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a current collector and a battery cell. Background Art

[0003] In power batteries, there are many ways to set the tabs of square batteries. One of them is that the positive tabs and negative tabs are respectively set at the two ends of the core package in the longitudinal direction, and a current collector is used as a transition piece between the tabs and the pole. The core package is composed of a positive electrode sheet, a negative electrode sheet and a diaphragm stacked in sequence. It has two end faces and a wide face and a narrow face connected to the two end faces. The current collector includes a horizontal part, a vertical part and a welding part. Among them, the horizontal part is parallel to the end face of the core package and is connected to the pole; the vertical part is parallel to the narrow face of the core package, one end of which is connected to the horizontal part and one side is connected to the welding part. In order to facilitate welding the tabs to the current collector, the welding part is parallel to the tabs during welding. After welding is completed, in order to facilitate the core package to enter the shell, the welding part needs to be bent at the connection between the welding part and the vertical part so that the welding part is closer to the vertical part, thereby reducing the distance between the welding part and the core package. SUMMARY OF THE INVENTION

[0004] After this current collector is bent, there is a large gap at the connection between the welding part and the vertical part, which causes the current collector to be larger in the length direction of the core package, and then causes the current collector to occupy more space inside the battery cell, which has an adverse effect on the energy density of the battery cell.

[0005] Furthermore, after bending, this gap creates a larger gap between the welded portion and the vertical portion on one side of the connection, while the gap between the welded portion and the vertical portion on the other side is smaller. This results in poor parallelism between the welded portion and the vertical portion, which in turn causes the edge of the welded portion away from the bend to bulge toward the battery cell's insulation and pierce the insulation. This can lead to a risk of short circuiting within the battery.

[0006] In a first aspect, the present application provides a current collecting part, which includes a first conductive part, the first conductive part extending along a first direction, the first conductive part having a first surface facing away from the core package, the first surface being provided with a groove, the groove extending along the first direction; wherein, the groove divides the first conductive part into a vertical part and a welding part.

[0007] In a second aspect, the present application provides a battery cell comprising a shell, a core pack, a pole and a current collector; the shell has a receiving cavity; the core pack is arranged in the receiving cavity; the pole is passed through one end of the shell; and the current collector connects the pole to the pole ear of the core pack.

[0008] In a third aspect, the present application provides a battery pack, which includes a battery box and the aforementioned battery cells, wherein there are multiple battery cells, and the multiple battery cells are arranged in the battery box. Beneficial effects

[0009] The present application can reduce the material of the connection part between the vertical part and the welding part by setting a groove between the vertical part and the welding part, thereby reducing the internal stress of the welding part during the bending process toward the vertical part, and further reducing the obstruction of the connection part to the welding part moving toward the vertical part, so that the gap between the welding part and the vertical part is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG1 is a schematic structural diagram of a current collecting member provided in an embodiment of the present application;

[0011] Figure 2 is an enlarged view of point A in Figure 1;

[0012] FIG3 is a schematic diagram of the first bending of the welding portion according to an embodiment of the present application and the coupling with the tab;

[0013] FIG4 is a schematic diagram of the welding portion provided in an embodiment of the present application being matched with the tab after being bent for the second time;

[0014] FIG5 is a schematic structural diagram of a groove after the welding portion is bent for the second time according to an embodiment of the present application;

[0015] FIG6 is a schematic structural diagram of another groove after the welding portion is bent for the second time according to an embodiment of the present application;

[0016] FIG7 is a schematic structural diagram of a groove provided in an embodiment of the present application;

[0017] FIG8 is a schematic structural diagram of another current collecting member provided in an embodiment of the present application;

[0018] FIG9 is an enlarged view of point B in FIG8 ;

[0019] FIG10 is a schematic structural diagram of another groove after the welding portion is bent for the second time according to an embodiment of the present application;

[0020] FIG11 is a schematic structural diagram of another groove provided in an embodiment of the present application;

[0021] FIG12 is a partial structural schematic diagram of a longitudinal section of a pole mating hole provided in an embodiment of the present application;

[0022] FIG13 is a schematic diagram of the cooperation between the horizontal portion and the pole provided in an embodiment of the present application;

[0023] FIG14 is a schematic structural diagram of a battery cell provided in an embodiment of the present application;

[0024] FIG15 is an enlarged view of point C in FIG14 .

[0025] Description of the accompanying drawings:

[0026] 001-current collecting parts;

[0027] 011-horizontal portion; 111-pole mating hole; 112-third surface; 113-first sinking platform; 114-fourth surface; 115-second sinking platform;

[0028] 012-vertical part;

[0029] 013-first conductive portion; 131-groove; 1311-first groove wall; 132-first surface; 133-second surface; 134-middle groove;

[0030] 014-Welding department;

[0031] 002-battery cell; 021-shell; 211-accommodation cavity; 022-cover; 023-core package; 024-pole; 025-ear. Modes for Carrying Out the Invention

[0032] Please refer to Figure 1 and Figure 1. Figure 1 is a structural schematic diagram of a current collecting part 001 provided in an embodiment of the present application, and Figure 2 is an enlarged view of point A in Figure 1. An embodiment of the present application provides a current collecting part 001, which includes a first conductive part 013. The first conductive part 013 is extended along a first direction. The first conductive part 013 has a first surface 132 facing away from the core package. The first surface 132 is provided with a groove 131. The groove 131 is extended along the first direction. Among them, the groove 131 divides the first conductive part 013 into a vertical part 012 and a welding part 014.

[0033] The first direction is the axial direction of the battery cell.

[0034] It can be understood that the current collecting part 001 is mainly formed by stamping of a plate. After stamping, the vertical portion 012 and the welding portion 014 are located in the same horizontal plane. In order to adapt to the connection between the tab and the current collecting part 001, the welding portion 014 is bent for the first time at the connection between the welding portion 014 and the vertical portion 012 so that the welding portion 014 is perpendicular to the vertical portion 012. In a state where the welding portion 014 is perpendicular to the vertical portion 012, the tab is welded to the welding portion 014, as shown in FIG3 , which is a schematic diagram of the welding portion 014 provided in an embodiment of the present application cooperating with the tab during the first bending. After the tab is welded to the welding portion 014, the welding portion 014 is bent for the second time at the connection between the welding portion 014 and the vertical portion 012 so that the welding portion 014 is closer to the vertical portion 012, as shown in FIG4 , which is a schematic diagram of the welding portion 014 provided in an embodiment of the present application cooperating with the tab after the second bending. After the first conductive portion 013 is provided with the groove 131 , the welding portion 014 is bent toward the vertical portion 012 with the groove 131 as an axis, so that the welding portion 014 is parallel to the vertical portion 012 and close to the vertical portion 012 .

[0035] Specifically, when there is only one groove 131, it can be arranged adjacent to the welding portion 014, as shown in FIG5 , which is a schematic structural diagram of the groove 131 after the welding portion 014 is bent for the second time according to an embodiment of the present application; it can also be arranged adjacent to the vertical portion 012, as shown in FIG6 , which is a schematic structural diagram of another groove 131 after the welding portion 014 is bent for the second time according to an embodiment of the present application. FIG5 and FIG6 show schematic cross-sectional views of the current collecting member 001 perpendicular to the extension direction of the groove 131 after the welding portion 014 is bent for the second time. In FIG5 and FIG6 , the angle between the center line of the groove wall on both sides of the groove 131 and the surface of the welding portion 014 facing the vertical portion 012 is α, which satisfies the following conditions: 90°<α<180°. Based on the setting of the groove 131, the gap size a between the welding part 014 and the vertical part 012 is small. For example, when the thickness d0 of the current collecting part 001 is 2 mm, a≤3 mm. When the thickness d0 of the current collecting part 001 is 0.5 mm, the relative surfaces between the welding part 014 and the vertical part 012 are in contact with each other, that is, a=0.

[0036] The parallelism of the welding portion 014 relative to the vertical portion 012 is n, which satisfies: n≤1.

[0037] In addition, the current collecting member 001 is made of a conductive material, which may be, but is not limited to, a nickel sheet, a nickel-plated metal sheet, an aluminum sheet, or a copper sheet.

[0038] Exemplarily, the groove 131 may be, but is not limited to, a V-shaped groove, a rectangular groove, a semicircular groove, or a trapezoidal groove.

[0039] In this embodiment, by providing a groove 131 between the vertical portion 012 and the welding portion 014, the material of the connection portion between the vertical portion 012 and the welding portion 014 can be reduced, thereby reducing the internal stress of the welding portion 014 during the bending process toward the vertical portion 012, and further reducing the obstruction of the connection portion to the welding portion 014 approaching the vertical portion 012, so that the gap between the welding portion 014 and the vertical portion 012 is reduced.

[0040] Thus, on the one hand, the space occupied by the current collector 001 inside the battery cell 002 can be reduced, and on the other hand, the spacing between the two sides of the welding portion 014 and the vertical portion 012 can be made consistent, thereby improving the parallelism between the welding portion 014 and the vertical portion 012, so as to avoid the edge of the welding portion 014 on the side away from the bending portion protruding toward the insulating part of the battery cell 002, thereby ultimately improving the reliability of the battery.

[0041] In addition, by providing the groove 131 , the welding portion 014 can be guided by the groove 131 to bend, thereby ensuring that the welding portion 014 can bend along the groove 131 , thereby improving the bending accuracy and bending consistency of the current collecting member 001 .

[0042] In addition, the current collecting part 001 is a metal part with elasticity. By setting the groove 131, the rebound amplitude of the welding part 014 after bending can be controlled and reduced, thereby improving the bending accuracy of the welding part 014, which is beneficial to improving the position accuracy of the welding part 014, and further beneficial to the welding of the tab and the welding part 014 and the insertion of the core package 023 into the shell.

[0043] Please refer to Figure 7, which is a schematic diagram of the structure of the groove 131 provided in an embodiment of the present application. In one embodiment, the width of the groove 131 is d1, and the width of the groove bottom of the groove 131 is d2, which satisfies: d1>d2.

[0044] It can be understood that when the width of the groove 131 is not greater than the width of the bottom of the groove 131, when the welding portion 014 bends toward the vertical portion 012, the groove walls on both sides of the groove 131 will collide and squeeze each other, thereby causing the internal stress during the bending process to be greater, hindering the welding portion 014 from moving closer to the vertical portion 012, and not conducive to reducing the gap between the welding portion 014 and the vertical portion 012.

[0045] Based on this, in this embodiment, by setting the width of the opening of the groove 131 to be greater than the width of the groove bottom of the groove 131, the groove walls on both sides of the groove 131 can be prevented from abutting and squeezing each other during the bending process of the welding portion 014. This can further reduce the internal stress of the welding portion 014 during the bending process toward the vertical portion 012, thereby reducing the obstruction of the connection between the welding portion 014 and the vertical portion 012 to the welding portion 014 moving toward the vertical portion 012. As a result, the gap between the welding portion 014 and the vertical portion 012 can be reduced.

[0046] Referring to FIG. 7 , in one embodiment, the width of the notch of the groove 131 is d1 , and the thickness of the first conductive portion 013 is d0 , which satisfies the following relationship: 0.3 d0 ≤ d1 ≤ 4.3 d0 .

[0047] It can be understood that d1 can be but is not limited to 0.3 d0, 0.9 d0, 1.3 d0, 1.5 d0, 2 d0, 2.3 d0, 0.3 d0, 0.3 d0, 0.3 d0, 0.3 d0, 0.3 d0, 4.3 d0.

[0048] In this embodiment, by limiting the width of the notch of the groove 131, on the one hand, it can avoid that the width of the notch is too small and the internal stress during the bending process is not significantly eliminated, and on the other hand, it can avoid that the width of the notch is too large and the strength of the current collecting member 001 is reduced.

[0049] Referring to FIG. 7 , in one embodiment, the width of the bottom of the groove 131 is d2 , satisfying the following condition: d2 > 0.

[0050] Exemplarily, d2≥0.2d0. For example, when d0 is 4 mm, d2≥0.8 mm.

[0051] In this embodiment, by limiting the width of the groove 131, a larger gap is created between the groove walls on both sides of the groove 131. This prevents the groove walls on both sides of the groove 131 from interfering with or squeezing each other when the welding portion 014 is bent. This reduces the internal stress of the welding portion 014 during the bending process toward the vertical portion 012, thereby reducing the obstruction of the connection between the welding portion 014 and the vertical portion 012 from the welding portion 014 moving toward the vertical portion 012. As a result, the gap between the welding portion 014 and the vertical portion 012 can be reduced.

[0052] 7 , in one embodiment, the first conductive portion 013 has a second surface 133 away from the first surface 132 . The thickness of the first conductive portion 013 is d0 , and the minimum distance between the second surface 133 and the bottom of the groove 131 is d3 , satisfying the following relationship: 0.3d0 ≤ d3 ≤ 0.97d0 .

[0053] It can be understood that d3 can be but is not limited to 0.3 d0, 0.36 d0, 0.4 d0, 0.45 d0, 0.5 d0, 0.53 d0, 0.58 d0, 0.6 d0, 0.7 d0, 0.8 d0, 0.93 d0, and 0.97 d0.

[0054] In addition, the thickness d0 of the first conductive portion 013 refers to the distance between the first surface 132 and the second surface 133 when the first conductive portion 013 is not provided with the groove 131 .

[0055] In this embodiment, by limiting the minimum distance between the second surface 133 and the bottom of the groove, on the one hand, the strength of the current collector 001 at the groove 131 can be ensured based on the minimum value of the limited distance, thereby avoiding cracks in the current collector 001 at the groove 131; on the other hand, the minimum depth of the groove 131 can be ensured based on the maximum value of the limited distance, thereby reducing the internal stress of the welding portion 014 during the bending process toward the vertical portion 012. As a result, the connection between the vertical portion 012 and the welding portion 014 can reduce the obstruction of the welding portion 014 from approaching the vertical portion 012, thereby reducing the gap between the welding portion 014 and the vertical portion 012, and can also help improve the bending consistency of the welding portion 014 along the length direction of the groove 131, thereby reducing the impact of inconsistent bending on the battery energy density.

[0056] Please refer to Figures 8 and 9. Figure 8 is a schematic structural diagram of another current collecting member 001 provided in an embodiment of the present application, and Figure 9 is an enlarged view of point B in Figure 8. In one embodiment, there are two grooves 131. The two grooves 131 are arranged side by side between the vertical portion 012 and the welding portion 014.

[0057] Specifically, when there are two grooves 131, after the welding portion 014 is bent twice, the structure of the groove 131 is shown in Figure 10, which is a schematic diagram of the structure of another groove 131 after the welding portion 014 is bent for the second time according to an embodiment of the present application. In Figure 10, the groove 131 near the welding portion 014 is the first groove 131, and the angle between the center line of the groove walls on both sides of the first groove 131 and the surface of the welding portion 014 facing the vertical portion 012 is α, which satisfies the following: 90°<α<180°. The second groove 131 near the vertical portion 012, the angle between the center line of the groove walls on both sides of the second groove 131 and the surface of the welding portion 014 facing the vertical portion 012 is β, which satisfies the following: 90°<β<180°.

[0058] After the second bend of weld portion 014, the surface of the connection between weld portion 014 and vertical portion 012 facing away from groove 131 can be composed of two arc segments, one of which connects the surface of vertical portion 012 to the other arc segment, and the other arc segment connects the surface of weld portion 014 to the previous arc segment. The surface of this connection facing away from groove 131 can also be composed of two arc segments and a flat segment located between the two arc segments, as shown in Figure 10. In the thickness direction of weld portion 014, the width of the flat segment is h, satisfying the following: ⅓d0 < h < 3d0.

[0059] It can be understood that the two grooves 131 can be arranged at intervals, or the adjacent sides of the two grooves 131 can be connected to each other, that is, the adjacent groove walls of the two grooves 131 are arranged to intersect with each other.

[0060] In addition, since the current collecting member 001 has a certain thickness, when the welding portion 014 is bent to be close to the vertical portion 012, two corners are formed between the vertical portion 012 and the welding portion 014. The stress at the corners is relatively high, which greatly hinders the bending of the welding portion 014.

[0061] When bending, the welding portion 014 is bent toward the vertical portion 012 with the central symmetry line between the two grooves 131 as the axis, so that the welding portion 014 is parallel to the vertical portion 012 and moves closer to the vertical portion 012 .

[0062] Based on this, in this embodiment, by providing two grooves 131, on the one hand, the stress can be reduced by reducing the material at the two corners, so as to reduce the obstruction of the connection between the welding portion 014 and the vertical portion 012 to the welding portion 014 moving closer to the vertical portion 012, thereby reducing the gap between the welding portion 014 and the vertical portion 012; on the other hand, based on the grooves 131 provided at the two corners, the bending can be concentrated in the two grooves 131, thereby providing a more accurate bending guide for the bending of the welding portion 014, thereby improving the bending accuracy of the welding portion 014.

[0063] In addition, through the above setting, the rebound amplitude of the welding part 014 after bending is controlled and reduced, thereby improving the bending accuracy of the welding part 014, which is beneficial to improving the position accuracy of the welding part 014, and further beneficial to the welding of the tab and the welding part 014 and the insertion of the core package 023 into the shell.

[0064] Please refer to Figure 11, which is a schematic diagram of the structure of another groove 131 provided in an embodiment of the present application. In one embodiment, an intermediate groove 134 is provided on the first surface 132. The intermediate groove 134 extends along the axis of the groove 131. The intermediate groove 134 is located between two grooves 131. Both sides of the intermediate groove 134 in the width direction respectively penetrate the two grooves 131, that is, the bottom of the intermediate groove 134 intersects with the adjacent groove walls of the two grooves 131.

[0065] It can be understood that when bending, the welding portion 014 is bent toward the vertical portion 012 with the middle groove 134 as the axis, so that the welding portion 014 is parallel to the vertical portion 012 and moves closer to the vertical portion 012 .

[0066] In this embodiment, by providing the middle groove 134, the material between the two grooves 131 can be reduced, thereby reducing the internal stress of the welding portion 014 during the bending process toward the vertical portion 012, and further reducing the obstruction of the connection between the welding portion 014 and the vertical portion 012 to the welding portion 014 approaching the vertical portion 012, so that the gap between the welding portion 014 and the vertical portion 012 is reduced.

[0067] Referring to FIG. 11 , in one embodiment, the thickness of the first conductive portion 013 is d0 , and the distance between the first surface 132 and the bottom of the middle groove 134 is d4 , satisfying the relationship: 0<d4≤⅔d0.

[0068] It can be understood that d4 can be but is not limited to 0.1 d0, 0.22 d0, 0.28 d0, 0.3 d0, 0.4 d0, 0.51 d0, 0.6d0, and ⅔ d0.

[0069] In this embodiment, through the above-mentioned definition, on the one hand, an intermediate groove 134 can be provided between the two groove bottoms to reduce the material between the two grooves 131, thereby reducing the internal stress of the welding portion 014 during the bending process toward the vertical portion 012, so as to improve the bending consistency of the welding portion 014 on the groove 131; on the other hand, the strength of the current collecting part 001 at the groove 131 is ensured based on the maximum depth of the intermediate groove 134 defined, thereby avoiding cracks in the current collecting part 001 at the intermediate groove 134.

[0070] In one embodiment, the two grooves 131 have a first groove wall 1311 close to the middle groove 134, the first groove walls 1311 of the two grooves 131 are intersected, and the middle groove 134 is arranged at the intersection between the first groove walls 1311; or, the two grooves 131 are arranged at intervals, and along the width direction of the middle groove 134, the middle of the middle groove 134 is arranged in the interval between the two grooves 131, and the two sides of the middle groove 134 are respectively connected to the two grooves 131.

[0071] It is understood that the two grooves 131 can be spaced apart or partially intersected. For example, when the thickness of the current collecting member 001 is relatively small, the two grooves 131 can be partially intersected. When the thickness of the current collecting member 001 is relatively large, the two grooves 131 can be spaced apart.

[0072] Referring to FIG1 , in one embodiment, the current collecting member 001 further includes a horizontal portion 011 . The horizontal portion 011 is disposed along the second extension. The second direction intersects the first direction. Specifically, the second direction is perpendicular to the vertical portion.

[0073] It can be understood that after the current collector 001 is stamped from sheet metal, the horizontal portion 011, vertical portion 012, and welding portion 014 lie in the same horizontal plane. To accommodate the connection between the electrode post and the tab, the horizontal portion 011 is bent at the junction between the horizontal portion 011 and the vertical portion 012, making it perpendicular to the vertical portion 012. When the current collector is applied to a battery cell, the horizontal portion 011 is parallel to the cell's top cover.

[0074] Specifically, a pole mating hole 111 is provided on the horizontal portion 011 .

[0075] It can be understood that the end of the pole close to the horizontal portion 011 is plugged into the pole matching hole 111. After plugging, the pole and the horizontal portion 011 are fixed by welding.

[0076] The clearance between the terminal and the terminal mating hole 111 is t, which satisfies the following conditions: 0.025 mm ≤ t ≤ 1 mm. The clearance t can be, but is not limited to, 0.025 mm, 0.075 mm, 0.128 mm, 0.3 mm, 0.6 mm, 0.7 mm, 0.85 mm, 0.92 mm, or 1 mm.

[0077] In this embodiment, by providing the pole matching hole 111 on the horizontal portion 011 , the pole can be plugged into the horizontal portion 011 based on the hole, thereby improving the positioning accuracy between the pole and the horizontal portion 011 .

[0078] Please refer to Figure 12, which is a partial structural schematic diagram of a longitudinal cross-section of a pole mating hole 111 provided in an embodiment of the present application. In one embodiment, along the axis of the groove 131, the horizontal portion 011 has a third surface 112 that faces away from the vertical portion 012. A first recessed platform 113 is provided on the third surface 112. The first recessed platform 113 is arranged along the circumference of the pole mating hole 111. The first recessed platform 113 is connected to the pole mating hole 111.

[0079] It is understood that a ring body is provided on the outer circumference of the pole to cooperate with the first recessed platform 113. The end of the pole near the horizontal portion 011 is inserted into the pole mating hole 111, and the ring body is located in the first recessed platform 113 and engages with the first recessed platform 113, as shown in Figure 13, which is a schematic diagram of the cooperation between the horizontal portion 011 and the pole provided in an embodiment of the present application.

[0080] In this embodiment, through the above arrangement, the matching surface between the horizontal portion 011 and the pole can be increased, thereby improving the positioning accuracy between the horizontal portion 011 and the pole.

[0081] Referring to FIG. 12 , in one embodiment, along the axis of the groove 131 , the horizontal portion 011 has a fourth surface 114 facing away from the vertical portion 012 . The fourth surface 114 is provided with a second recessed platform 115 . The second recessed platform 115 is disposed along the circumference of the terminal mating hole 111 . The second recessed platform 115 is in communication with the terminal mating hole 111 .

[0082] It can be understood that the pole is welded to the horizontal portion 011 , for example, by laser welding.

[0083] Based on this, in this embodiment, by providing the second sinking platform 115, the operability of welding between the pole and the horizontal portion 011 is improved, thereby facilitating the improvement of the welding quality between the pole and the horizontal portion.

[0084] Please refer to Figure 14, which is a schematic diagram of the structure of a battery cell 002 provided in an embodiment of the present application. Accordingly, an embodiment of the present application also provides a battery cell 002, which includes a housing, a core pack 023, a pole 024, and a current collector 001. The housing has a receiving cavity 211. The core pack 023 is disposed in the receiving cavity 211. The pole 024 is provided through one end of the housing; the current collector 001 connects the pole 024 to the tab 025 of the core pack 023.

[0085] It can be understood that when the core package 023 is located in the accommodating cavity 211 , one side surface of the core package is disposed opposite to the welding portion 014 , as shown in FIG. 15 , which is an enlarged view of point C in FIG. 14 .

[0086] The housing includes a cover 022 and a shell 021 , wherein the cover 022 covers one end of the shell 021 . The pole 024 is provided on the cover 022 .

[0087] Additionally, battery cell 002 can be used in a battery. The battery includes a battery box and battery cells 002. Multiple battery cells 002 are disposed within the battery box. Multiple battery cells 002 are connected in parallel or in series. The battery is used in electrical equipment, such as electric vehicles.

[0088] In this embodiment, the use of current collector 001 reduces the gap between weld portion 014 and vertical portion 012. This not only reduces the space occupied by current collector 001 within battery cell 002, thereby increasing the energy density of battery cell 002, but also improves the parallelism between weld portion 014 and vertical portion 012, preventing the edge of weld portion 014, away from the connection with vertical portion 012, from protruding toward the insulating member of battery cell 002, thereby improving the reliability of battery cell 002.

Claims

1. A current collecting member (001), comprising a first conductive portion (013), the first conductive portion (013) extending along a first direction, the first conductive portion (013) having a first surface (132) facing away from a core package (023), the first surface (132) being provided with a groove (131), the groove (131) extending along the first direction; wherein, The groove (131) divides the first conductive portion (013) into a vertical portion (012) and a welding portion (014).

2. The current collecting member (001) according to claim 1, wherein: The width of the groove (131) is d1, and the width of the groove bottom of the groove (131) is d2, which satisfies: d1>d2.

3. The current collecting member (001) according to claim 1 or 2, wherein: The width of the notch of the groove (131) is d1, and the thickness of the first conductive portion (013) is d0, which satisfies the following relationship: 0.3 d0≤d1≤4.3 d0.

4. The current collecting member (001) according to any one of claims 1 to 3, wherein: The width of the groove bottom of the groove (131) is d2, which satisfies: d2>0.

5. The current collecting member (001) according to any one of claims 1 to 4, wherein: The first conductive portion (013) has a second surface (133) facing away from the first surface (132), the thickness of the first conductive portion (013) is d0, and the minimum distance between the second surface (133) and the bottom of the groove (131) is d3, satisfying the following: 0.3d0≤d3≤0.97d0.

6. The current collecting member (001) according to any one of claims 1 to 5, wherein: There are two grooves (131), and the two grooves (131) are arranged in parallel between the vertical portion (012) and the welding portion (014).

7. The current collecting member (001) according to claim 6, wherein: An intermediate groove (134) is provided on the first surface (132), and the intermediate groove (134) extends along the axis of the groove (131). The intermediate groove (134) is located between the two grooves (131), and both sides of the intermediate groove (134) in the width direction are respectively connected to the two grooves (131).

8. The current collecting member (001) according to claim 7, wherein: The thickness of the first conductive portion (013) is d0, and the distance between the first surface (132) and the bottom of the middle groove (134) is d4, satisfying: 0<d4≤⅔d0.

9. The current collecting member (001) according to claim 7 or 8, wherein: The two grooves (131) have a first groove wall (1311) close to the middle groove (134), the first groove walls (1311) of the two grooves (131) are arranged to intersect, and the middle groove (134) is arranged at the intersection between the first groove walls (1311); Alternatively, the two grooves (131) are spaced apart, the middle groove (134) is disposed between the two grooves (131), and both sides of the middle groove (134) are respectively connected to the two grooves (131).

10. A battery cell (002), comprising: A housing having a receiving cavity (211); A core package (023) is disposed in the accommodating cavity (211); A pole (024) is provided through one end of the housing; The current collecting piece (001) according to any one of claims 1 to 9, wherein the current collecting piece (001) connects the pole (024) to the pole lug (025) of the core package (023).

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