Cylindrical battery cell, battery device, and electric apparatus

Abstract

The present application relates to the technical field of batteries, and provides a cylindrical battery cell, a battery device, and an electric apparatus. The cylindrical battery cell comprises a casing, an electrode terminal, an electrode assembly, and a first current collecting member; the electrode terminal is arranged on the wall portion of the casing; the electrode assembly is accommodated inside the casing, and comprises a main body portion and a first tab protrudingly arranged on the end of the main body portion facing the wall portion; the first current collecting member comprises a current collecting main body region, an elastic region, and a terminal connecting region; the current collecting main body region is arranged between the wall portion and the first tab in the thickness direction of the wall portion, and is electrically connected to the first tab; two opposite ends of the elastic region in the direction of extension of the elastic region are respectively connected to the current collecting main body region and the terminal connecting region; the terminal connecting region is connected to the electrode terminal. In this way, the elastic region can deform between the electrode terminal and the first current collecting member, thereby being conducive to reducing rigid pulling between the electrode terminal and the first current collecting member, and reducing the risk of electrical connection failure between the electrode terminal and the electrode assembly.

Description

Cylindrical battery cells, battery packs and electrical devices Cross-reference to related applications

[0001] This application claims priority to international patent application PCT / CN2024 / 125928, filed on October 18, 2024, entitled “Cylindrical Battery Cell, Battery Device and Power Consumption Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and more specifically, to a cylindrical battery cell, a battery device, and an electrical device. Background Technology

[0003] In recent years, new energy vehicles have experienced rapid development. In the field of electric vehicles, power batteries, as the power source, play an irreplaceable and crucial role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also increasing. Among them, batteries, as core components of new energy vehicles, have high requirements in terms of stability and service life.

[0004] In battery technology, a battery device includes a housing and cylindrical battery cells disposed within the housing. The cylindrical battery cell includes a casing and an electrode assembly housed within the casing. The electrode assembly has tabs, which are connected to electrode terminals disposed on the casing via current collectors, so that the input or output of electrical energy of the cylindrical battery cell can be realized through the electrode terminals. However, in the prior art, cylindrical battery cells are prone to the risk of connection failure between the electrode assembly and the electrode terminals during use, which is not conducive to improving the stability and service life of the cylindrical battery cells. Summary of the Invention

[0005] This application provides a cylindrical battery cell, a battery device, and an electrical device, which can effectively improve the stability and service life of the cylindrical battery cell.

[0006] In a first aspect, embodiments of this application provide a cylindrical battery cell, including a housing, electrode terminals, an electrode assembly, and a first current collector; the housing has a wall portion, the thickness direction of which is the axial direction of the cylindrical battery cell; the electrode terminals are disposed on the wall portion; the electrode assembly is housed within the housing, the electrode assembly including a main body portion and a first tab, the first tab protruding from one end of the main body portion facing the wall portion; the first current collector is housed within the housing, the first current collector comprising a current collector body region, an elastic region, and a terminal connection region, at least a portion of the current collector body region being disposed between the wall portion and the first tab in the thickness direction of the wall portion, and the current collector body region being electrically connected to the first tab, the elastic region being connected to the current collector body region and the terminal connection region at opposite ends in its extending direction, and the terminal connection region being connected to the electrode terminals.

[0007] In the above technical solution, the first current collector component is provided with a current collector body area, an elastic area, and a terminal connection area. The current collector body area is electrically connected to the first electrode tab, and the terminal connection area is connected to the electrode terminal. By setting the elastic area to have its two ends connected to the current collector body area and the terminal connection area respectively in its extension direction, the elastic area is a strip structure connecting the current collector body area and the terminal connection area. This allows the electrical connection between the electrode terminal and the electrode assembly to be achieved, while also enabling the elastic area connecting the current collector body area and the terminal connection area to have the ability to deform. This allows the elastic area to deform when the terminal connection area and the current collector body area move closer or further apart along the thickness direction of the wall. On the one hand, this allows the terminal connection area to withstand compression, etc. When the phenomenon occurs, it can move along the thickness direction of the wall, thereby absorbing the assembly error between the electrode terminal and the terminal connection area, which is beneficial to improving the assembly quality between the electrode terminal and the terminal connection area. On the other hand, the elastic area can play a certain buffering role between the current collector body area and the terminal connection area, thereby alleviating the rigid tension between the current collector body area and the terminal connection area, between the terminal connection area and the electrode terminal, and between the current collector body area and the first electrode tab when the electrode assembly shakes or shifts. This helps to reduce the risk of electrical connection failure between the electrode terminal and the electrode assembly, and also helps to reduce the phenomenon of the first current collector being damaged by tension, thereby effectively improving the stability and service life of the cylindrical battery cell.

[0008] In some embodiments, the orthographic projection of the terminal connection area and the orthographic projection of the current collection body area do not overlap in a projection plane perpendicular to the thickness direction of the wall portion.

[0009] In the above technical solution, by setting the terminal connection area and the current collector body area as structures where their projections in the thickness direction of the wall do not overlap, the obstruction and interference of the current collector body area on the terminal connection area can be reduced when the terminal connection area is close to or far from the current collector body area in the thickness direction of the wall. This is beneficial to expanding the range of movement of the terminal connection area relative to the current collector body area in the thickness direction of the wall, thereby further improving the deformation degree of the elastic area in the thickness direction of the wall. This further enhances the effect of the elastic area in absorbing assembly errors between the electrode terminal and the terminal connection area, thereby further improving the assembly quality between the electrode terminal and the terminal connection area. It also further enhances the buffering effect of the elastic area between the current collector body area and the terminal connection area, thereby further reducing the risk of electrical connection failure between the electrode terminal and the electrode assembly.

[0010] In some embodiments, the orthographic projection of the elastic zone and the orthographic projection of the current collection body zone do not overlap in a projection plane perpendicular to the thickness direction of the wall.

[0011] In the above technical solution, by setting the elastic zone and the current collector body area as structures where their projections in the thickness direction of the wall do not overlap, the current collector body area can reduce the obstruction and interference effect on the elastic zone when the terminal connection area and the current collector body area move closer or further away from each other along the thickness direction of the wall, thus reducing the deformation of the elastic zone. This allows the elastic zone to deform better during assembly or use, and helps to increase the degree of deformation of the elastic zone in the thickness direction of the wall. This further enhances the effect of the elastic zone in absorbing assembly errors between the electrode terminal and the terminal connection area, thereby improving the assembly quality between the electrode terminal and the terminal connection area. It also further enhances the buffering effect of the elastic zone between the current collector body area and the terminal connection area, thereby further reducing the risk of electrical connection failure between the electrode terminal and the electrode assembly.

[0012] In some embodiments, the electrode terminals and the terminal connection area are arranged along the thickness direction of the wall portion. Along the thickness direction of the wall portion, the terminal connection area has a first surface facing away from the main body portion, and the electrode terminal has a connection surface facing the main body portion. The connection surface is connected to the first surface.

[0013] In the above technical solution, by setting the electrode terminals and the terminal connection area to be arranged along the thickness direction of the wall, and connecting the first surface of the terminal connection area away from the main body to the connection surface of the electrode terminal facing the main body, on the one hand, the assembly difficulty between the electrode terminals and the terminal connection area can be reduced, and the connection stability and overcurrent stability between the terminal connection area and the electrode terminals can be improved. On the other hand, under the action of the elastic area, the assembly error between the electrode terminals and the terminal connection area can be absorbed, thereby improving the assembly quality between the terminal connection area and the electrode terminals.

[0014] In some embodiments, along the thickness direction of the wall portion, the flow collection body region has a second surface facing away from the body portion, and the second surface is further away from the body portion than the first surface.

[0015] In the above technical solution, by setting the second surface of the current collector area away from the main body to be further away from the main body in the thickness direction of the wall than the first surface of the terminal connection area that connects to the electrode terminal, the electrode terminal is structured to press down on the terminal connection area in the thickness direction of the wall towards the main body. On the one hand, this can reduce the assembly gap between the first surface of the terminal connection area and the connection surface of the electrode terminal, which is conducive to further improving the assembly quality between the terminal connection area and the electrode terminal. On the other hand, it can also realize that the connection surface of the electrode terminal is closer to the main body in the thickness direction of the wall than the second surface, thereby enabling the electrode terminal and the current collector area to share part of the space in the thickness direction of the wall, which is conducive to improving the internal space utilization of the cylindrical battery cell.

[0016] In some embodiments, along the thickness direction of the wall portion, the terminal connection area has a third surface facing the main body portion, and the current collection main body area has a fourth surface facing the main body portion, the fourth surface being further away from the main body portion than the third surface.

[0017] In the above technical solution, by further setting the third surface of the terminal connection area facing the main body to be closer to the main body in the thickness direction of the wall than the fourth surface of the current collection main body area facing the main body, the terminal connection area is a structure that is sunken in the direction closer to the main body in the thickness direction of the wall compared to the current collection main body area. This can further improve the effect of the electrode terminal pressing the terminal connection area, thereby reducing the assembly gap between the first surface of the terminal connection area and the connection surface of the electrode terminal, which is conducive to further improving the assembly quality between the terminal connection area and the electrode terminal.

[0018] In some embodiments, the first electrode tab has a fifth surface facing the first current collector in the thickness direction of the wall portion, the current collector body region abuts against the fifth surface, and the fifth surface is provided with a relief portion recessed in the thickness direction of the wall portion away from the electrode terminal; wherein, at least a portion of the terminal connection region is located within the relief portion along the thickness direction of the wall portion.

[0019] In the above technical solution, by setting at least a portion of the terminal connection area in the thickness direction of the wall to be accommodated in the clearance portion of the first tab, at least a portion of the terminal connection area is inserted into the clearance portion. The cylindrical battery cell with this structure can achieve the first tab to avoid the terminal connection area while also enabling the terminal connection area and the first tab to share a portion of the space in the thickness direction of the wall, which is beneficial to improving the internal space utilization of the cylindrical battery cell.

[0020] In some embodiments, along the thickness direction of the wall portion, the flow collection body region has a second surface facing away from the body portion, and the second surface is closer to the body portion than the first surface.

[0021] In the above technical solution, by setting the second surface of the current collection main body area away from the main body to be closer to the main body in the thickness direction of the wall than the first surface of the terminal connection area away from the main body, the first surface of the terminal connection area can be closer to the connection surface of the electrode terminal in the thickness direction of the wall than the second surface of the current collection main body area. On the one hand, this facilitates the assembly and connection between the first surface of the terminal connection area and the connection surface of the electrode terminal, and can better absorb the assembly error between the electrode terminal and the terminal connection area. On the other hand, it allows the electrode terminal to press the terminal connection area down better in the thickness direction of the wall towards the main body, which helps to reduce the assembly gap between the first surface of the terminal connection area and the connection surface of the electrode terminal, thereby effectively improving the assembly quality between the terminal connection area and the electrode terminal.

[0022] In some embodiments, at least a portion of the elastic region deforms and bends.

[0023] In the above technical solution, by setting the elastic region as a structure that is at least partially bent and deformed, the elastic region is in a state of accumulating elastic force after the electrode terminal presses the terminal connection area, so that the elastic region can press the first surface of the terminal connection area tightly against the connection surface of the electrode terminal along the thickness direction of the wall, thereby further reducing the assembly gap between the first surface of the terminal connection area and the connection surface of the electrode terminal, which is beneficial to further improve the assembly quality between the terminal connection area and the electrode terminal.

[0024] In some embodiments, along the thickness direction of the wall portion, the first electrode tab has a fifth surface facing the wall portion, and the current collecting body region abuts against the fifth surface; wherein, the fifth surface is provided with a relief portion recessed in the thickness direction of the wall portion away from the electrode terminal, and the projection of the terminal connection area in the thickness direction of the wall portion is located within the relief portion.

[0025] In the above technical solution, by providing a clearance portion on the fifth surface of the first electrode ear facing the wall and abutting against the current collector body area, and setting the projection of the terminal connection area in the thickness direction of the wall to be located within the clearance portion, the terminal connection area is configured to correspond to the clearance portion of the first electrode ear in the thickness direction of the wall. This allows the terminal connection area to be inserted into the clearance portion when it is close to or far from the current collector body area in the thickness direction of the wall, thereby achieving clearance between the first electrode ear and the terminal connection area. On the one hand, this reduces the obstruction and interference of the first electrode ear on the terminal connection area, which is beneficial to expanding the range of movement of the terminal connection area relative to the current collector body area in the thickness direction of the wall, thereby further improving the deformation degree of the elastic area in the thickness direction of the wall. On the other hand, it can alleviate the phenomenon of the terminal connection area pressing down on the first electrode ear during use or assembly, which is beneficial to reducing the phenomenon of damage to the first electrode ear, and can reduce the risk of short circuit caused by the first electrode ear being inserted backward into the body.

[0026] In some embodiments, at least a portion of the terminal connection area is accommodated within the clearance portion along the thickness direction of the wall portion.

[0027] In the above technical solution, by setting at least a portion of the terminal connection area in the thickness direction of the wall to be accommodated in the clearance portion, at least a portion of the terminal connection area is inserted into the clearance portion. The cylindrical battery cell with this structure can achieve the first tab to avoid the terminal connection area while also enabling the terminal connection area and the first tab to share a portion of the space in the thickness direction of the wall, which is beneficial to improving the internal space utilization of the cylindrical battery cell.

[0028] In some embodiments, at least a portion of the projection of the elastic zone lies within the clearance portion along the thickness direction of the wall portion.

[0029] In the above technical solution, by setting at least a portion of the projection of the elastic region in the thickness direction of the wall portion to be located within the clearance portion, the elastic region is configured such that at least a portion of the clearance portion of the first electrode is correspondingly provided in the thickness direction of the wall portion. This allows the first electrode to avoid at least a portion of the elastic region when the elastic region deforms along the thickness direction of the wall portion. On the one hand, this reduces the obstruction and interference of the first electrode on the elastic region, which is beneficial to expanding the deformation range of the elastic region. On the other hand, it alleviates the phenomenon of the elastic region pressing down on the first electrode during use or assembly, which is beneficial to reducing the phenomenon of damage to the first electrode and reducing the risk of short circuit caused by the first electrode being inserted backward into the main body.

[0030] In some embodiments, the clearance portion forms a clearance opening on the fifth surface, the clearance portion includes a first circumferential surface surrounding the clearance opening, the clearance opening is formed at one end of the first circumferential surface connected to the fifth surface along the thickness direction of the wall portion, and the first circumferential surface is inclined from the clearance opening toward the central axis of the cylindrical battery cell; wherein, in a projection plane perpendicular to the thickness direction of the wall portion, at least a portion of the orthographic projection of the elastic region and the orthographic projection of the first circumferential surface overlap.

[0031] In the above technical solution, the first circumferential surface of the avoidance part is connected to the fifth surface at one end to form an avoidance opening, and the avoidance opening is located on the fifth surface. By setting the first circumferential surface to be inclined from the avoidance opening toward the central axis of the cylindrical battery cell, the first circumferential surface is an inclined surface that is larger at the end closer to the fifth surface and smaller at the end farther away from the fifth surface in the thickness direction of the wall. The orthogonal projection of the elastic region and the first circumferential surface in the projection plane perpendicular to the thickness direction of the wall is set to be at least partially overlapping, so that the first circumferential surface is a structure that corresponds to the elastic region in the thickness direction of the wall. This allows the first circumferential surface of the avoidance part to fit the deformation of the elastic region, so that the avoidance part can avoid the elastic region. It can also further expand the avoidance range of the avoidance part to the elastic region without excessively reducing the first electrode tab, thereby improving the avoidance effect of the avoidance part to the elastic region while meeting the overcurrent requirements of the first electrode tab.

[0032] In some embodiments, the first circumferential surface is a conical surface.

[0033] In the above technical solution, by setting the first circumferential surface as a conical structure, it is beneficial to improve the regularity of the first circumferential surface, thereby further improving the avoidance effect of the avoidance part on the elastic zone, and reducing the processing and forming difficulty of the first circumferential surface, so as to reduce the manufacturing difficulty of the cylindrical battery cell.

[0034] In some embodiments, the electrode assembly has a central through hole that extends through both ends of the electrode assembly along the thickness direction of the wall portion, and the clearance portion is a portion of the central through hole.

[0035] In the above technical solution, the electrode assembly is provided with a central through hole that extends through both ends of the electrode assembly along the thickness direction of the wall. By setting part of the central through hole as a clearance part for avoiding the terminal connection area, the clearance part can not only avoid the terminal connection area, but also cooperate with the central through hole for venting. This is beneficial to improve the internal venting smoothness of the cylindrical battery cell and can reduce the manufacturing difficulty of the electrode assembly.

[0036] In some embodiments, the central through hole includes a first hole segment and a second hole segment that are interconnected, at least a portion of the first hole segment is located within the main body, the second hole segment is located within the first electrode tab, and the second hole segment is the clearance portion; wherein, the minimum diameter of the second hole segment is greater than the diameter of the first hole segment.

[0037] In the above technical solution, by setting the second hole segment located inside the first electrode tab as a clearance part, and setting the hole diameter of the second hole segment to be larger than that of the first hole segment, the effect of the second hole segment as a clearance part to avoid the terminal connection area can be improved, while also alleviating the phenomenon of the first hole segment located inside the main body occupying too much space, thereby helping to improve the energy density of the electrode assembly.

[0038] In some embodiments, the terminal connection area is connected to the current collection body area only through one of the elastic areas.

[0039] In the above technical solution, by setting the terminal connection area to be connected to the current collection body area only through an elastic area, the elastic area can be better deformed when the terminal connection area and the current collection body area move closer or further away from each other along the thickness direction of the wall, which is beneficial to further expand the range of movement of the terminal connection area relative to the current collection body area in the thickness direction of the wall.

[0040] In some embodiments, the first current collector includes a plurality of the elastic regions, and the terminal connection region is connected to the current collector body region through the plurality of elastic regions.

[0041] In the above technical solution, by setting the terminal connection area to be interconnected with the current collection body area through multiple elastic areas, it is beneficial to improve the connection reliability between the terminal connection area and the current collection body area, and can further increase the current flow area between the terminal connection area and the current collection body area.

[0042] In some embodiments, the current collection body area, the elastic area, and the terminal connection area are integrally formed.

[0043] In the above technical solution, by setting the current collection body area, elastic area and terminal connection area of ​​the first current collection component as an integrated structure, on the one hand, the connection difficulty between the elastic area and the current collection body area and the terminal connection area can be reduced, thereby reducing the processing difficulty of the first current collection component. On the other hand, the connection reliability and stability between the current collection body area, elastic area and terminal connection area can be improved, which is conducive to alleviating the phenomenon of breakage between the current collection body area and the elastic area and between the elastic area and the terminal connection area during use, thereby reducing the risk of connection failure between the electrode terminals and the electrode assembly.

[0044] In some embodiments, the Vickers hardness of the elastic region is greater than or equal to 10 and less than or equal to 70.

[0045] In the above technical solution, by setting the Vickers hardness of the elastic zone to 10 to 70, the elastic zone has good structural strength and good deformation capacity. This allows the elastic zone to play a good buffering role between the current collector area and the terminal connection area, while also providing good support for the terminal connection area. This helps to alleviate the problem of poor assembly caused by the terminal connection area failing to make effective contact with the electrode terminal.

[0046] In some embodiments, the material of the elastic region includes aluminum.

[0047] In the above technical solution, using aluminum material for the elastic zone enables the elastic zone to have good flow conduction capacity while also enabling it to have good deformation capacity.

[0048] In some embodiments, the current collection body area is an annular structure surrounding the terminal connection area, the terminal connection area and the current collection body area are spaced apart, and the elastic area is connected at opposite ends in its extending direction to the outer peripheral surface of the terminal connection area and the inner peripheral surface of the current collection body area, respectively.

[0049] In the above technical solution, by setting the current collector body area as an annular structure surrounding the outer side of the terminal connection area, and the elastic area connecting its two opposite ends in its extension direction to the outer peripheral surface of the terminal connection area and the inner peripheral surface of the current collector body area respectively, the elastic area is a structure connecting the terminal connection area and the current collector body area. The first current collector component with this structure is convenient for the elastic area to deform and for the terminal connection area to be assembled and connected to the electrode terminal, which helps to reduce the connection difficulty between the terminal connection area and the electrode terminal. On the other hand, it can optimize the structural layout of the current collector body area, the elastic area and the terminal connection area, so as to facilitate the assembly of the current collector body area of ​​the first current collector component between the wall and the first electrode ear, which helps to improve the structural stability of the current collector body area of ​​the first current collector component set between the wall and the first electrode ear.

[0050] In some embodiments, the orthographic projection of the elastic region extends radially along the cylindrical battery cell in a projection plane perpendicular to the thickness direction of the wall portion.

[0051] In the above technical solution, by setting the orthographic projection of the elastic region in the projection plane perpendicular to the thickness direction of the wall as a structure extending radially along the cylindrical battery cell, the elastic region is a strip-shaped structure arranged radially along the cylindrical battery cell between the current collector body area and the terminal connection area. This facilitates the deformation of the elastic region when the current collector body area and the terminal connection area move closer or further apart along the thickness direction of the wall, which helps to improve the buffering effect of the elastic region between the current collector body area and the terminal connection area, and can improve the effect of the elastic region in absorbing the assembly error between the terminal connection area and the electrode terminal. On the other hand, it can improve the regularity of the shape of the first current collector component, which helps to reduce the processing difficulty of the first current collector component.

[0052] In some embodiments, the elastic region is connected to the current collection body region and the terminal connection region at opposite ends in its extension direction, and the elastic region has a dimension D in its extension direction, and the radius of the current collection body region is R, satisfying 0.4R≤D≤0.95R.

[0053] In the above technical solution, by setting the dimension D of the elastic region in its extension direction to be greater than or equal to 0.4 times the radius R of the current collector body region, the elastic region has sufficient length to deform, which is beneficial to improving the ability of the elastic region to deform when the current collector body region and the terminal connection region move closer or further apart along the thickness direction of the wall. In addition, by setting the dimension D of the elastic region in its extension direction to be less than or equal to 0.95 times the radius R of the current collector body region, the phenomenon of the terminal connection region being too small due to excessive space occupied by the elastic region is alleviated, which is beneficial to increasing the connection area between the terminal connection region and the electrode terminal, thereby improving the current flow area and connection reliability between the terminal connection region and the electrode terminal.

[0054] In some embodiments, 8mm ≤ D ≤ 25mm.

[0055] In the above technical solution, by setting the size of the elastic region in its extension direction to be greater than or equal to 8mm, the elastic region has sufficient length to deform, which is beneficial to further improve the ability of the elastic region to deform when the current collector area and the terminal connection area are close to or far apart along the thickness direction of the wall. In addition, by setting the size of the elastic region in its extension direction to be less than or equal to 25mm, the phenomenon of insufficient strength of the elastic region caused by excessively long size is alleviated, so that the elastic region can better support the terminal connection area, thereby effectively alleviating the phenomenon of poor assembly caused by the terminal connection area not being able to make effective contact with the electrode terminal.

[0056] In some embodiments, the first collector component further includes a base region, and the elastic region is connected to the collector body region through the base region. In a projection plane perpendicular to the thickness direction of the wall, the width of the orthographic projection of the base region in the circumferential direction of the collector body region is greater than the width of the orthographic projection of the elastic region in the circumferential direction of the collector body region.

[0057] In the above technical solution, the first current collection component is also provided with a base region connecting the elastic region and the current collection main region. The width of the base region in the circumferential direction of the current collection main region is greater than the width of the elastic region in the circumferential direction of the current collection main region. This makes the elastic region a structure that is connected to the current collection main region through the base region with a larger width. This helps to reduce the connection difficulty between the elastic region and the current collection main region of the ring structure, and can improve the connection stability of the elastic region connected to the inner circumferential surface of the current collection main region.

[0058] In some embodiments, the base region has a first end and a second end opposite to each other, the first end being connected to the elastic region and the second end being connected to the current collection body region; wherein, in a projection plane perpendicular to the thickness direction of the wall, the width of the orthographic projection of the base region in the circumferential direction of the current collection body region gradually increases from the first end to the second end.

[0059] In the above technical solution, by setting the base region to have a gradually increasing width in the circumferential direction of the main flow collection area from the first end connected to the elastic region to the second end connected to the main flow collection area, on the one hand, the width of the end connecting the base region and the elastic region can be reduced, which helps to reduce the width difference at the connection position between the base region and the elastic region, thereby reducing the connection difficulty and molding difficulty between the base region and the elastic region, and enabling a smoother transition at the connection position between the base region and the elastic region. On the other hand, increasing the width of the second end connecting the base region and the main flow collection area can expand the angle at the connection position between the inner circumferential surfaces of the base region and the main flow collection area, thereby alleviating the stress concentration phenomenon at the connection position between the base region and the main flow collection area, which helps to reduce the risk of damage or cracking at the connection position between the base region and the main flow collection area, thereby improving the reliability and service life of the first flow collection component.

[0060] In some embodiments, the first current collector further includes a tab connection area; the tab connection area is connected to the inner circumferential surface of the current collector body area, and the tab connection area is connected to the first tab to electrically connect the current collector body area and the first tab.

[0061] In the above technical solution, the first current collector is also provided with an electrode connection area for interconnection with the first electrode ear, and the electrode connection area is connected to the inner circumferential surface of the current collector body area. On the one hand, it is convenient for the current collector body area to be connected to the first electrode ear through the electrode connection area, which helps to reduce the connection difficulty between the first current collector and the first electrode ear and can increase the connection area between the first current collector and the first electrode ear. On the other hand, it can optimize the structural layout between the electrode connection area and the current collector body area, so as to assemble the current collector body area of ​​the first current collector between the wall and the first electrode ear, which helps to improve the structural stability of the current collector body area of ​​the first current collector set between the wall and the first electrode ear.

[0062] In some embodiments, the tab connection area extends radially along the cylindrical battery cell.

[0063] In the above technical solution, by setting the tab connection area as a structure extending radially along the cylindrical battery cell, the connection area between the tab connection area and the first tab can be increased, thereby improving the connection stability between the tab connection area and the first tab. Furthermore, the first tab can be connected to the tab connection area at multiple positions in the radial direction of the cylindrical battery cell, so that the multi-turn structure of the first tab of the cylindrical electrode assembly can be connected to the tab connection area. This is beneficial to increasing the current flow area between the first tab and the tab connection area, and can also improve the current flow balance between the electrode assembly and the tab connection area, thereby reducing the risk of local lithium plating in the electrode assembly during use.

[0064] In some embodiments, in a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projections of the terminal connection area and the elastic area do not overlap with the orthographic projection of the tab connection area.

[0065] In the above technical solution, by setting the projections of the terminal connection area and the elastic area in the thickness direction of the wall to not overlap with the projection of the tab connection area in the thickness direction of the wall, the obstruction and interference of the tab connection area on the terminal connection area and the elastic area can be reduced when the terminal connection area is close to or far away from the current collector body area in the thickness direction of the wall. This is beneficial to expanding the movement range of the terminal connection area relative to the current collector body area in the thickness direction of the wall, and can improve the deformation degree of the elastic area in the thickness direction of the wall. This can further improve the effect of the elastic area in absorbing the assembly error between the electrode terminal and the terminal connection area, thereby further improving the assembly quality between the electrode terminal and the terminal connection area, and can further improve the buffering effect of the elastic area between the current collector body area and the terminal connection area, thereby further reducing the risk of electrical connection failure between the electrode terminal and the electrode assembly.

[0066] In some embodiments, the first current collector includes a plurality of tab connection regions, which are arranged at circumferential intervals along the current collector body region.

[0067] In the above technical solution, by connecting multiple tab connection areas on the current collector body area, and the multiple tab connection areas are arranged at intervals along the circumference of the current collector body area, on the one hand, the connection area between the first current collector component and the first tab can be further increased, thereby increasing the flow area between the first current collector component and the first tab. On the other hand, it can realize that the first tab is connected to multiple positions in the circumference of the body area, which is beneficial to improving the flow balance between the electrode assembly and the first current collector component, thereby reducing the risk of local lithium plating in the electrode assembly during use.

[0068] In some embodiments, the terminal connection area is welded to one end of the electrode terminal near the body portion.

[0069] In the above technical solution, by setting the terminal connection area to be welded to the end of the electrode terminal near the main body in the thickness direction of the wall, the terminal connection area is a structure welded to the end face of the electrode terminal near the main body in the thickness direction of the wall. On the one hand, it can improve the connection stability and overcurrent stability between the terminal connection area and the electrode terminal. On the other hand, under the action of the elastic zone, it can absorb the assembly error between the electrode terminal and the terminal connection area, thereby alleviating the welding gap between the terminal connection area and the electrode terminal. This helps to reduce the risk of poor welding between the terminal connection area and the electrode terminal, thereby improving the welding quality between the terminal connection area and the electrode terminal.

[0070] In some embodiments, the electrode assembly has a central through hole that extends through both ends of the electrode assembly along the thickness direction of the wall portion; wherein the terminal connection area is welded to the electrode terminal to form a connection portion, and the projection of the connection portion is located within the central through hole along the thickness direction of the wall portion.

[0071] In the above technical solution, by setting the connection portion formed by welding the terminal connection area and the electrode terminal together, the projection of the connection portion in the thickness direction of the wall portion is located in the central through hole. This allows the welding assembly to be performed from the side of the terminal connection area away from the electrode terminal through the central through hole when welding the terminal connection area and the electrode terminal. This helps to reduce the power required for welding the terminal connection area and the electrode terminal together, thereby reducing the welding difficulty between the terminal connection area and the electrode terminal. It also improves the welding quality between the terminal connection area and the electrode terminal, thereby improving the connection reliability between the terminal connection area and the electrode terminal.

[0072] In some embodiments, the electrode terminal includes a terminal body and a protrusion; the terminal body is connected to the wall portion; the protrusion is connected to the terminal body, and along the thickness direction of the wall portion, the protrusion protrudes from one end of the terminal body facing the main body portion, and the end of the protrusion near the main body portion is connected to the terminal connection area.

[0073] In the above technical solution, the electrode terminal includes a terminal body connected to the wall and a protrusion protruding from one end of the terminal body near the main body. The protrusion is connected to the terminal connection area of ​​the first current collector. The electrode terminal with this structure can reduce the connection difficulty between the electrode terminal and the terminal connection area and reduce the interference between the terminal connection area and the terminal body. On the other hand, it is convenient for the electrode terminal to press down on the terminal connection area along the thickness direction of the wall through the protrusion, which is beneficial to absorb the assembly error between the electrode terminal and the terminal connection area, thereby effectively improving the assembly quality between the terminal connection area and the electrode terminal.

[0074] In some embodiments, the terminal body has a first limiting portion and a second limiting portion, the first limiting portion and the second limiting portion are spaced apart along the thickness direction of the wall portion, and at least a portion of the wall portion is located between the first limiting portion and the second limiting portion.

[0075] In the above technical solution, by providing a first limiting part and a second limiting part arranged at intervals along the thickness direction of the wall on the terminal body, and at least a part of the wall is located between the first limiting part and the second limiting part, the first limiting part and the second limiting part of the terminal body are respectively located on both sides of the wall in the thickness direction of the wall, so that the first limiting part and the second limiting part can cooperate to clamp the wall, thereby realizing the installation of the terminal body of the electrode terminal on the wall. The structure is simple and easy to implement and assemble.

[0076] In some embodiments, the cylindrical battery cell further includes a first insulating member; the first insulating member includes a first insulating portion disposed between the wall portion and the first current collector in the thickness direction of the wall portion; wherein the first insulating portion is provided with a through hole, the through hole penetrating both sides of the first insulating portion in the thickness direction of the wall portion, the electrode terminal extending into the through hole along the thickness direction of the wall portion, and the protrusion protruding from the surface of the first insulating portion facing the first current collector.

[0077] In the above technical solution, the cylindrical battery cell is further provided with a first insulating member. The first insulating member includes a first insulating portion disposed between the wall and the first current collector in the thickness direction of the wall. By setting the protrusion to protrude from the surface of the first insulating portion facing the first current collector in the thickness direction of the wall, the obstruction and interference of the first insulating portion on the protrusion can be reduced, so that the protrusion and the terminal connection area can be connected to each other, which helps to reduce the connection difficulty between the protrusion and the terminal connection area.

[0078] In some embodiments, the cylindrical battery cell further includes a first insulating member, the first insulating member including a first insulating portion, the first insulating portion being disposed between the wall portion and the first current collector in the thickness direction of the wall portion to insulate and isolate the wall portion and the first current collector; wherein, the first insulating portion is provided with a through hole, the through hole penetrating both sides of the first insulating portion in the thickness direction of the wall portion, and the electrode terminal extending into the through hole along the thickness direction of the wall portion.

[0079] In the above technical solution, the cylindrical battery cell is further provided with a first insulating member, and the first insulating member includes a first insulating portion disposed in the thickness direction of the wall portion between the wall portion and the first current collector, so that the first insulating portion of the first insulating member can insulate and separate the wall portion and the first current collector, thereby reducing the risk of short circuit between the wall portion and the first current collector during use. In this case, by providing a through hole extending along the thickness direction of the wall portion on the first insulating portion, and the electrode terminal extending into the through hole along the thickness direction of the wall portion, it is convenient for the electrode terminal to be connected to the terminal connection area of ​​the first current collector located on the side of the first insulating portion away from the wall portion, which helps to reduce the assembly difficulty between the electrode terminal and the first current collector.

[0080] In some embodiments, the electrode terminals and the terminal connection area are arranged along the thickness direction of the wall portion. Along the thickness direction of the wall portion, the terminal connection area has a first surface facing away from the main body portion, and the electrode terminal has a connection surface facing the main body portion. The connection surface and the first surface are welded together. In this embodiment, along the thickness direction of the wall portion, the first insulating portion has a sixth surface facing the first tab, and the sixth surface is further away from the main body portion than the connection surface.

[0081] In the above technical solution, by setting the sixth surface of the first insulating part facing the first electrode tab to be closer to the main body in the thickness direction of the wall portion than the connecting surface where the electrode terminal and the terminal connection area are connected, the end of the electrode terminal near the main body in the thickness direction of the wall portion is a structure that protrudes from the side of the first insulating part facing the first electrode tab. This reduces the obstruction and interference of the first insulating part on the electrode terminal, making it easier for the connecting surface of the electrode terminal to be welded to the first surface of the terminal connection area. On the other hand, it facilitates the electrode terminal to press the terminal connection area along the thickness direction of the wall portion, which is beneficial to improving the contact effect between the first surface and the connecting surface. This effectively improves the welding quality between the first surface and the connecting surface, thereby reducing phenomena such as incomplete soldering between the terminal connection area and the electrode terminal.

[0082] In some embodiments, the electrode terminals and the terminal connection area are arranged along the thickness direction of the wall portion. Along the thickness direction of the wall portion, the terminal connection area has a first surface facing away from the main body portion, and the electrode terminal has a connection surface facing the main body portion. The connection surface and the first surface are welded together. In this embodiment, along the thickness direction of the wall portion, the first insulating portion has a sixth surface facing the first tab, and the sixth surface is closer to the main body portion than the connection surface.

[0083] In the above technical solution, by setting the sixth surface of the first insulating part facing the first electrode tab to be closer to the main body in the thickness direction of the wall part than the connection surface of the electrode terminal, the end of the electrode terminal near the main body in the thickness direction of the wall part is located in the through hole and does not extend out of the side of the first insulating part facing the first electrode tab. This reduces the phenomenon that the electrode terminal occupies the space of the side of the first insulating part facing the first electrode tab and reduces the interference between the electrode terminal and other components.

[0084] In some embodiments, at least a portion of the terminal connection area is accommodated within the through hole along the thickness direction of the wall portion.

[0085] In the above technical solution, by setting at least a portion of the terminal connection area to be accommodated in the through hole in the thickness direction of the wall, the terminal connection area can share a portion of the space with the first insulating part in the thickness direction of the wall, which is beneficial to improving the internal space utilization rate of the cylindrical battery cell.

[0086] In some embodiments, the wall portion is provided with a mounting hole that penetrates the wall portion along its thickness direction. The electrode terminal passes through the mounting hole. The cylindrical battery cell further includes a sealing member disposed between the electrode terminal and the wall portion to seal the gap between the electrode terminal and the hole wall surface of the mounting hole. The electrode terminal includes a first limiting portion located on the side of the wall portion facing the electrode assembly. The sealing member is made of insulating material and includes a first sealing portion located between the wall portion and the first limiting portion in the thickness direction of the wall portion. The first sealing portion extends beyond the first limiting portion in the radial direction of the cylindrical battery cell in a direction away from the central axis of the cylindrical battery cell. At least a portion of the first sealing portion and the first limiting portion are accommodated within the through hole. A first gap is formed between the first sealing portion and the hole wall surface of the through hole along the radial direction of the cylindrical battery cell.

[0087] In the above technical solution, the cylindrical battery cell is further provided with a sealing element, which is disposed between the electrode terminal and the wall portion. This allows the sealing element to seal the gap between the electrode terminal and the wall surface of the mounting hole, thereby mitigating the risk of leakage from the mounting hole during use. The sealing element includes a first sealing portion disposed between the wall portion and the first limiting portion. By configuring at least a portion of the first sealing portion and the first limiting portion to be accommodated within a through hole, the sealing effect of the sealing element on the electrode terminal and the wall portion is further improved. A first gap is formed between the first sealing portion of the sealing element and the wall surface of the through hole, facilitating the assembly of the first sealing portion of the sealing element within the through hole. This reduces interference between the first sealing portion of the sealing element and the first insulating portion of the first insulating element, effectively reducing the assembly difficulty of the cylindrical battery cell. Furthermore, the sealing element is made of insulating material, enabling it to achieve insulation between the electrode terminal and the wall portion while sealing the gap between the electrode terminal and the wall surface of the mounting hole, thus reducing the risk of short circuit between the electrode terminal and the wall portion.

[0088] In some embodiments, the cylindrical battery cell further includes a second insulating member; the second insulating member is located between the wall portion and the first current collector in the thickness direction of the wall portion, and the projection of the second insulating member in the thickness direction of the wall portion covers the first gap.

[0089] In the above technical solution, by providing a second insulating member between the wall and the first current collector, and the projection of the second insulating member in the thickness direction of the wall covers the first gap between the first sealing part and the first insulating part, the second insulating member can block the first gap, thereby increasing the creepage distance between the wall and the first current collector at the first gap, and thus effectively mitigating the risk of short circuit or electrical breakdown between the wall and the first current collector at the first gap, so as to improve the reliability of the cylindrical battery cell.

[0090] In some embodiments, the second insulating member protrudes from the wall surface of the through hole.

[0091] In the above technical solution, by setting the second insulating member as a structure protruding from the hole wall of the first insulating part, the second insulating member is connected to the hole wall of the first insulating part. This allows the second insulating member to share a portion of the space with the first insulating part in the thickness direction of the wall. This helps to alleviate the phenomenon that the second insulating member occupies the space between the wall and the first insulating part or between the first current collector and the first insulating part in the thickness direction of the wall. This improves the internal space utilization rate of the cylindrical battery cell and increases the energy density of the cylindrical battery cell.

[0092] In some embodiments, the second insulating member is integrally formed with the first insulating portion.

[0093] In the above technical solution, by setting the second insulating member and the first insulating part of the first insulating member as an integrally formed structure, on the one hand, the reliability and stability of the second insulating member protruding from the hole wall of the through hole of the first insulating part can be improved, which helps to reduce the risk of the second insulating member falling off the first insulating part during use, thereby improving the reliability of the second insulating member blocking the first gap. On the other hand, it can reduce the difficulty of setting the second insulating member on the hole wall of the through hole of the first insulating part, which helps to reduce the manufacturing difficulty of the cylindrical battery cell.

[0094] In some embodiments, the second insulating member is disposed between the first insulating portion and the first current collecting member along the thickness direction of the wall portion.

[0095] In the above technical solution, by placing the second insulating component between the first insulating part and the first current collector, it is beneficial to reduce the assembly difficulty of the second insulating component and improve the production efficiency of the cylindrical battery cell.

[0096] In some embodiments, the second insulating member is connected to the surface of the first current collector member facing the wall portion.

[0097] In the above technical solution, by setting the second insulating member as a structure connected to the surface of the first current collector facing the wall, on the one hand, the stability and reliability of the second insulating member set between the first insulating part and the first current collector can be improved, which is conducive to reducing the phenomenon of the second insulating member moving or shifting during use. On the other hand, it is possible to set the second insulating member on the first current collector and then assemble it together with the first current collector into the housing, which is conducive to reducing the assembly difficulty of the second insulating member and optimizing the production cycle of the cylindrical battery cell.

[0098] In some embodiments, the second insulating member is connected to the surface of the first insulating portion facing the first current collector.

[0099] In the above technical solution, by setting the second insulating member as a structure connected to the surface of the first insulating part facing the first current collector, on the one hand, the stability and reliability of the second insulating member being disposed between the first insulating part and the first current collector can be improved, which is conducive to reducing the phenomenon of the second insulating member moving or shifting during use. On the other hand, the second insulating member can be assembled onto the first insulating part first and the first gap can be blocked before the first current collector is assembled, which is conducive to reducing the assembly difficulty of the second insulating member and improving the effect of the second insulating member blocking the first gap.

[0100] In some embodiments, the orthographic projection of the terminal connection area does not overlap with the orthographic projection of the second insulating member in a projection plane perpendicular to the thickness direction of the wall portion.

[0101] In the above technical solution, by setting the terminal connection area and the second insulating member as structures in which their projections in the thickness direction of the wall do not overlap, the obstruction and interference of the second insulating member on the terminal connection area can be reduced, which helps to reduce the connection difficulty between the terminal connection area and the electrode terminal and improves the assembly quality between the terminal connection area and the electrode terminal.

[0102] In some embodiments, the terminal connection area is welded to the electrode terminal to form a connection portion, and the connection portion and the second insulating member are spaced apart radially in the cylindrical battery cell with a spacing greater than or equal to 5 mm.

[0103] In the above technical solution, by setting the second insulating component and the connecting part to be arranged radially on the cylindrical battery cell with a spacing greater than or equal to 5mm, the radial separation distance between the second insulating component and the connecting part on the cylindrical battery cell can be increased. This reduces the risk of high-temperature damage to the second insulating component by the connecting part during the welding connection of the terminal connection area and the electrode terminals to form the connecting part, thereby reducing the phenomenon of insulation failure after the second insulating component is damaged, and improving the production quality and reliability of the cylindrical battery cell.

[0104] In some embodiments, the second insulating member is disposed between the first insulating portion and the wall portion along the thickness direction of the wall portion.

[0105] In the above technical solution, by placing the second insulating member between the first insulating part and the wall part, it is beneficial to reduce the obstruction and interference between the second insulating member and the terminal connection area, thereby reducing the connection difficulty between the terminal connection area and the electrode terminal.

[0106] In some embodiments, the second insulating member is connected to the surface of the wall portion facing the first insulating portion.

[0107] In the above technical solution, by setting the second insulating member as a structure connected to the surface of the wall portion facing the first insulating portion, it is beneficial to improve the stability and reliability of the second insulating member being disposed between the first insulating portion and the wall portion, so as to reduce the phenomenon of the second insulating member shifting or displacing during use.

[0108] In some embodiments, in a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the second insulating member partially overlaps with the orthographic projection of the first sealing portion.

[0109] In the above technical solution, by setting the projections of the first sealing portion of the second insulating member and the sealing member in the thickness direction of the wall portion to an overlapping structure, the portion of the second insulating member is located between the first sealing portion of the sealing member and the wall portion in the thickness direction of the wall portion. This can further improve the stability and reliability of the second insulating member disposed between the wall portion and the first insulating portion, thereby further reducing the phenomenon of the second insulating member shifting or displacing during use. On the other hand, it can further improve the shielding effect of the second insulating member on the first gap, thereby further reducing the risk of short circuit or electrical breakdown between the wall portion and the first current collector at the first gap.

[0110] In some embodiments, in a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the second insulating member partially overlaps with the orthographic projection of the first insulating portion.

[0111] In the above technical solution, by setting the projection of the second insulating member in the thickness direction of the wall portion to partially overlap with the first insulating portion, the second insulating member is stacked on one side of the first insulating portion in the thickness direction of the wall portion, so that the second insulating member and the first insulating portion have overlapping areas, thereby improving the shielding effect of the second insulating member on the first gap, and further mitigating the risk of short circuit or electrical breakdown between the wall portion and the first current collector at the first gap.

[0112] In some embodiments, the first flow collector has a hollow area, and along the thickness direction of the wall portion, the wall portion has an exposed area corresponding to the first gap in the thickness direction of the wall portion, and a portion of the projection of the exposed area is located within the hollow area.

[0113] In the above technical solution, by forming a hollow area on the first current collector and setting the exposed area of ​​the wall corresponding to the first gap to be located in the hollow area in the thickness direction of the wall, it is beneficial to reduce the area of ​​the first current collector corresponding to the first gap in the thickness direction of the wall, thereby further mitigating the risk of short circuit or electrical breakdown between the wall and the first current collector at the first gap.

[0114] In some embodiments, the orthographic projection of the exposed area does not overlap with the orthographic projection of the first tab in a projection plane perpendicular to the thickness direction of the wall portion.

[0115] In the above technical solution, by setting the projections of the exposed area and the first electrode in the thickness direction of the wall to be non-overlapping, the projection of the first electrode in the thickness direction of the wall does not fall into the first gap, thereby effectively reducing the risk of short circuit between the first electrode and the wall after it is inserted into the first gap, and reducing the risk of electrical breakdown between the first electrode and the wall at the first gap.

[0116] In some embodiments, the first insulating portion is bonded to the wall portion.

[0117] In the above technical solution, by setting the first insulating part to be bonded to the wall, on the one hand, the assembly difficulty between the first insulating part and the wall can be reduced, thereby reducing the assembly difficulty of the cylindrical battery cell. On the other hand, the assembly stability of the first insulating part set in the shell can be improved, which helps to reduce the risk of the first insulating part moving or shaking during use.

[0118] In some embodiments, the first insulating member further includes a second insulating portion; the second insulating portion surrounds the first insulating portion, and the second insulating portion and the first insulating portion together define a receiving space; wherein the first current collector is received within the receiving space, and the first electrode tab is received within the receiving space along the thickness direction of the wall portion.

[0119] In the above technical solution, the first insulating member is further provided with a second insulating part surrounding the first insulating part, and the first insulating part and the second insulating part together form a receiving space for accommodating the first current collector and the first electrode tab. The cylindrical battery cell with this structure is convenient for assembling the first insulating member. Only one end of the electrode assembly with the first electrode tab needs to be inserted into the receiving space of the first insulating member to complete the assembly between the first insulating member and the electrode assembly, which helps to reduce the assembly difficulty between the first insulating member and the electrode assembly. On the other hand, the second insulating part can further realize the separation between the first electrode tab and the shell, as well as between the first current collector and the shell, which helps to improve the insulation isolation effect of the first insulating member between the first electrode tab and the shell, as well as between the first current collector and the shell, thereby reducing the risk of short circuit in the cylindrical battery cell and improving the reliability of the cylindrical battery cell.

[0120] In some embodiments, along the thickness direction of the wall portion, one end of the main body portion having the first electrode tab is accommodated within the accommodating space.

[0121] In the above technical solution, by setting the end of the main body with the first electrode tab to be accommodated in the accommodating space in the thickness direction of the wall, the first electrode tab and the first current collector are both integrally accommodated in the accommodating space, thereby further improving the insulation and isolation effect of the first insulating member on the first electrode tab and the shell, as well as the first current collector and the shell, so as to further reduce the risk of short circuit in the cylindrical battery cell during use.

[0122] In some embodiments, the electrode assembly further includes a second tab, which protrudes from one end of the main body away from the wall portion along the thickness direction of the wall portion; the cylindrical battery cell further includes a second current collector, which is disposed at one end of the electrode assembly away from the wall portion along the thickness direction of the wall portion and connected to the second tab; wherein, the housing further includes a sidewall, which surrounds the wall portion, and a protrusion is provided on the inner wall surface of the sidewall, the main body portion is located between the protrusion and the wall portion along the thickness direction of the wall portion, and the protrusion is connected to the second current collector to electrically connect the electrode assembly and the sidewall.

[0123] In the above technical solution, the electrode assembly is further provided with a second tab, and the cylindrical battery cell is further provided with a second current collector connected to the second tab. A protrusion is provided on the side wall of the outer casing, located at the end of the main body away from the wall in the thickness direction of the wall portion, and the second current collector is connected to the protrusion. This achieves electrical connection between the side wall of the outer casing and the electrode assembly, thereby enabling the input or output of electrical energy from the cylindrical battery cell. Cylindrical battery cells with this structure can reduce the difficulty of electrical connection between the second current collector and the side wall, thus reducing the assembly difficulty of the cylindrical battery cell. Furthermore, the protrusion in the thickness direction of the wall portion can also provide a certain degree of restraint on the main body of the electrode assembly, which helps to reduce the movement of the electrode assembly during use.

[0124] In some embodiments, the second current collector includes a first connection region, a second connection region, and a third connection region; the first connection region is located at one end of the electrode assembly away from the wall portion in the thickness direction of the wall portion and is connected to the second electrode tab; the second connection region is connected to the protrusion; the third connection region connects the first connection region and the second connection region, and the third connection region is configured to be deformable.

[0125] In the above technical solution, the second current collector is provided with a first connection area, a second connection area, and a third connection area. The first connection area and the second connection area are respectively connected to the second electrode and the protrusion, and the third connection area is connected between the first connection area and the second connection area to realize the second electrode and the side wall through the second current collector. In this way, by setting the third connection area as a structure that can deform when the first connection area and the second connection area move closer or further away from each other along the thickness direction of the wall, the third connection area can play a certain buffering role between the first connection area and the second connection area. In this way, when the electrode assembly shakes or shifts, it can alleviate the rigid tension between the first connection area and the second connection area, between the first connection area and the second electrode, and between the second connection area and the protrusion. This is beneficial to further reduce the risk of connection failure between the first connection area and the second electrode and between the second connection area and the protrusion, and also to reduce the phenomenon of the second current collector being damaged by tension.

[0126] In some embodiments, the third connection region is bent to form a plurality of bent segments, which are connected sequentially, and the bent segments at both ends of the plurality of bent segments are respectively connected to the first connection region and the second connection region.

[0127] In the above technical solution, by setting the third connecting area as a structure of multiple bent segments connected in sequence, and the bent segments at both ends of the multiple bent segments being connected to the first connecting area and the second connecting area respectively, the deformation capacity of the third connecting area when the first connecting area and the second connecting area move closer or further away from each other along the thickness direction of the wall can be increased, so as to further improve the buffering effect of the third connecting area between the first connecting area and the second connecting area, and further reduce the phenomenon of rigid tension between the first connecting area and the second connecting area, between the first connecting area and the second tab, and between the second connecting area and the protrusion.

[0128] In some embodiments, the second current collector includes a second connection area connected to the protrusion, and the second connection area is located on the side of the protrusion away from the wall along the thickness direction of the wall.

[0129] In the above technical solution, by setting the second connection area of ​​the second current collector for interconnection with the protrusion to be located on the side of the protrusion away from the wall in the thickness direction of the wall, the second connection area of ​​the second current collector and the main body of the electrode assembly are located on both sides of the protrusion in the thickness direction of the wall. The cylindrical battery cell with this structure can reduce the interference effect caused by the main body on the connection position of the second connection area and the protrusion, and can reduce the obstruction of the main body on the second connection area, which is conducive to reducing the connection difficulty between the second connection area and the protrusion, thereby reducing the assembly difficulty of the cylindrical battery cell.

[0130] In some embodiments, the second current collector is welded to the protrusion.

[0131] In the above technical solution, by setting the second current collector and the protrusion to a welded connection, it is beneficial to improve the connection stability and reliability between the second current collector and the protrusion, so as to reduce the risk of connection failure during use.

[0132] In some embodiments, the protrusion is a ring-shaped structure extending circumferentially along the sidewall.

[0133] In the above technical solution, by setting the protrusion as a ring structure extending circumferentially along the sidewall, on the one hand, the limiting or positioning effect of the protrusion on the main body of the electrode assembly can be further improved, and on the other hand, the protrusion can be connected to the second current collector at any position in the circumferential direction of the sidewall, so as to facilitate the assembly and connection between the second current collector and the protrusion. After the second current collector is assembled into the housing, there is no need to rotate and adjust the position and positioning of the second current collector to achieve the assembly and connection between the second current collector and the protrusion. This helps to further reduce the connection difficulty between the second current collector and the protrusion, thereby effectively improving the assembly efficiency of the cylindrical battery cell.

[0134] In some embodiments, the sidewall is formed on the side opposite to the electrode assembly and has a groove corresponding to the position of the protrusion.

[0135] In the above technical solution, by setting a groove on the side of the sidewall facing away from the electrode assembly and at the position corresponding to the protrusion, the protrusion formed on the side of the sidewall facing the electrode assembly can be a structure that can be formed by stamping. This allows a protrusion to be formed on the side of the sidewall facing the electrode assembly, and a groove to be formed on the other side at the position corresponding to the protrusion. Cylindrical battery cells with this structure can reduce the difficulty of forming a protrusion on the side of the sidewall facing the electrode assembly, which is beneficial to improving the production efficiency of cylindrical battery cells. On the other hand, it can make the interior of the protrusion a hollow structure, which can reduce the difficulty of assembling and connecting the protrusion and the second current collector, and enable the protrusion to have the ability of elastic deformation, which can further alleviate the rigid tension between the second current collector and the protrusion, thereby reducing the risk of connection failure between the second current collector and the protrusion.

[0136] In some embodiments, the housing includes a shell and an end cap; the shell includes an integrally formed sidewall and a bottom wall, the sidewall surrounding the bottom wall, one end of the sidewall being connected to the bottom wall along the thickness direction of the wall portion, and the other end forming an opening, the sidewall and the bottom wall together defining a receiving cavity, the electrode assembly being received within the receiving cavity; the end cap closes the opening; wherein, the bottom wall is the wall portion.

[0137] In the above technical solution, by setting the wall of the outer casing as the bottom wall opposite to the end cap, the wall where the electrode terminals are located can be moved away from the end cap. This can alleviate the phenomenon that the stress generated by the pulling or twisting of the electrode terminals by other components is transmitted to the connection position of the end cap and the casing, thereby reducing the risk of connection failure of the end cap and the casing, and improving the stability and reliability of the cylindrical battery cell.

[0138] In some embodiments, the housing includes a shell and an end cap; the interior of the shell has an opening in a receiving cavity in which the electrode assembly is received; the end cap closes the opening; wherein the end cap is the wall portion.

[0139] In the above technical solution, by setting the wall of the outer casing as an end cap for closing the opening of the casing, the cylindrical battery cell with this structure is easy to assemble electrode terminals on the end cap and can reduce the difficulty of assembling the first current collector between the wall and the electrode assembly, thereby reducing the manufacturing difficulty of the cylindrical battery cell and improving the production efficiency of the cylindrical battery cell.

[0140] Secondly, embodiments of this application also provide a battery device, including the aforementioned cylindrical battery cell.

[0141] Thirdly, embodiments of this application also provide an electrical device, including the aforementioned cylindrical battery cell, wherein the cylindrical battery cell is used to provide electrical energy. Attached Figure Description

[0142] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0143] Figure 1 is a structural schematic diagram of a vehicle provided in some embodiments of this application;

[0144] Figure 2 is an exploded view of the structure of a battery device provided in some embodiments of this application;

[0145] Figure 3 is a schematic diagram of the structure of a cylindrical battery cell provided in some embodiments of this application;

[0146] Figure 4 is an exploded view of the structure of a cylindrical battery cell provided in some embodiments of this application;

[0147] Figure 5 is a cross-sectional view of a cylindrical battery cell provided in some embodiments of this application;

[0148] Figure 6 is a partial enlarged view of point A of the cylindrical battery cell shown in Figure 5;

[0149] Figure 7 is a schematic diagram of the structure of the first current collection component provided in some embodiments of this application;

[0150] Figure 8 is a partial cross-sectional view of the electrode assembly of a cylindrical battery cell provided in some embodiments of this application;

[0151] Figure 9 is a cross-sectional view of the elastic region of the first current collector provided in some embodiments of this application, perpendicular to its extension direction;

[0152] Figure 10 is a front view of the first flow collection member provided in some embodiments of this application in the thickness direction of the wall portion;

[0153] Figure 11 is a cross-sectional view of the electrode terminals provided in some embodiments of this application;

[0154] Figure 12 is a cross-sectional view of a seal provided in some embodiments of this application;

[0155] Figure 13 is a cross-sectional view of the first insulating member of a cylindrical battery cell provided in some embodiments of this application;

[0156] Figure 14 is a cross-sectional view of a cylindrical battery cell provided in some embodiments of this application;

[0157] Figure 15 is a partial enlarged view of point B of the cylindrical battery cell shown in Figure 14;

[0158] Figure 16 is a cross-sectional view of a cylindrical battery cell provided in some embodiments of this application;

[0159] Figure 17 is a partial enlarged view of point C of the cylindrical battery cell shown in Figure 16;

[0160] Figure 18 is a schematic diagram of the structure of the second current collector provided in some embodiments of this application.

[0161] Icons: 1000 - Vehicle; 100 - Battery assembly; 10 - Housing; 11 - First housing body; 12 - Second housing body; 20 - Cylindrical battery cell; 21 - Casing; 211 - Wall; 2111 - Mounting hole; 2112 - Exposed area; 212 - Housing; 2121 - Opening; 2122 - Bottom wall; 2123 - Side wall; 2123a - Protrusion; 2123b - Groove; 213 - End cap; 22 - Electrode terminal; 221 - End Sub-body; 2211-First limiting part; 2212-Second limiting part; 222-Protrusion; 223-Connecting surface; 23-Electrode assembly; 231-Main body; 232-First electrode tab; 2321-Fifth surface; 2322-Allowing part; 2322a-Allowing opening; 2322b-First circumferential surface; 2323-Allowing hole; 233-Second electrode tab; 234-Central through hole; 2341-First hole segment; 2342-Second hole segment; 24 - First current collector component; 241- Current collector body area; 2411- Second surface; 2412- Fourth surface; 242- Elastic area; 243- Terminal connection area; 2431- First surface; 2432- Third surface; 244- Electrode connection area; 245- Base area; 2451- First end; 2452- Second end; 246- Hollowed-out area; 25- Sealing element; 251- First sealing part; 252- Second sealing part; 253- Third sealing element Part; 26-Second current collector; 261-First connection area; 262-Second connection area; 263-Third connection area; 2631-Bent section; 27-First insulating member; 271-First insulating part; 2711-Through hole; 2712-Sixth surface; 272-Second insulating part; 273-Accommodation space; 28-Connecting part; 29-Second insulating member; 30-First gap; 200-Controller; 300-Motor; X-Thickness direction of the wall part. Detailed Implementation

[0162] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0163] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0164] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0165] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0166] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0167] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0168] In this application, "multiple" means two or more (including two).

[0169] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0170] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0171] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0172] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0173] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0174] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0175] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0176] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0177] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0178] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, or titanium, etc. Foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0179] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0180] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0181] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0182] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0183] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0184] In some embodiments, the separator is a separator membrane. The separator membrane can be of various types, and any known porous separator membrane with good chemical and mechanical stability can be selected.

[0185] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0186] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0187] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0188] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0189] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0190] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0191] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0192] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0193] As an example, inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0194] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0195] In some implementations, the electrode assembly has a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0196] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0197] In some implementations, the electrode assembly has a positive tab and a negative tab.

[0198] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0199] As an example, a single battery cell can be cylindrical, i.e., a cylindrical battery cell.

[0200] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.

[0201] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0202] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0203] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0204] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0205] As an example, the enclosure may include a first enclosure body and a second enclosure body. The first enclosure body and the second enclosure body are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, which can be either sealed or unsealed. The first enclosure body may be a top cover or a bottom plate.

[0206] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0207] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0208] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0209] Battery devices possess outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide applicability, and low self-discharge coefficient, making them an important component of today's new energy development. The development of battery technology must simultaneously consider multiple design factors, such as performance parameters like energy density, cycle life, discharge capacity, and charge / discharge rate. Furthermore, the safety of the battery device must also be taken into account.

[0210] For a typical cylindrical battery cell, it usually includes a casing and an electrode assembly housed within the casing. The electrode assembly has tabs, and the casing has electrode terminals. By electrically connecting the tabs and electrode terminals, the cylindrical battery cell can input or output electrical energy through the electrode terminals. In related technologies, to reduce the assembly difficulty between the tabs and electrode terminals, a current collector is usually provided inside the casing. This current collector connects the tabs and electrode terminals to achieve the electrical connection. However, due to the complex operating conditions of cylindrical battery cells, vibration or shaking during use can cause damage to the electrode terminals and current collector. The connection structure between current collector components is prone to detachment, and manufacturing or assembly errors can cause assembly gaps between the electrode terminals and the current collector components, resulting in poor connection quality. In particular, in structures where the current collector components and electrode terminals are welded together, incomplete welds are likely to occur, leading to poor welding quality and thus poor connection stability. This, in turn, increases the risk of connection failure during use, which is detrimental to improving the stability and lifespan of cylindrical battery cells.

[0211] Based on the above considerations, in order to solve the problems of poor stability and short service life of cylindrical battery cells, this application provides a cylindrical battery cell, which includes a shell, electrode terminals, an electrode assembly, and a first current collector. The shell has a wall, the thickness direction of which is the axial direction of the cylindrical battery cell. The electrode terminals are disposed on the wall. The electrode assembly is housed within the shell and includes a main body and a first tab, the first tab protruding from the end of the main body facing the wall. The first current collector is housed within the shell and includes a current collector body region, an elastic region, and a terminal connection region. At least a portion of the current collector body region is disposed between the wall and the first tab in the thickness direction of the wall, and the current collector body region is electrically connected to the first tab. The elastic region is connected to the current collector body region and the terminal connection region at opposite ends in its extension direction, and the terminal connection region is connected to the electrode terminals.

[0212] In this type of cylindrical battery cell, the first current collector has a current collector body region, an elastic region, and a terminal connection region. The current collector body region is electrically connected to the first electrode tab, and the terminal connection region is connected to the electrode terminal. By setting the elastic region to have its two ends connected to the current collector body region and the terminal connection region respectively in its extension direction, the elastic region is a strip structure connecting the current collector body region and the terminal connection region. This allows the elastic region to deform while simultaneously achieving electrical connection between the electrode terminal and the electrode assembly. This enables the elastic region to deform when the terminal connection region and the current collector body region move closer or further apart along the thickness direction of the wall. On the one hand, this allows the terminal connection region to withstand compression. When subjected to pressure or other phenomena, it can move along the thickness direction of the wall, thereby absorbing assembly errors between the electrode terminals and the terminal connection area, which is beneficial to improving the assembly quality between the electrode terminals and the terminal connection area. On the other hand, the elastic area can play a certain buffering role between the current collector body area and the terminal connection area, thereby alleviating the rigid tension between the current collector body area and the terminal connection area, between the terminal connection area and the electrode terminals, and between the current collector body area and the first electrode tab when the electrode assembly shakes or shifts. This helps to reduce the risk of electrical connection failure between the electrode terminals and the electrode assembly, and also helps to reduce the phenomenon of the first current collector being damaged by tension, thus effectively improving the stability and service life of the cylindrical battery cell.

[0213] The cylindrical battery cells disclosed in this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power system for such an electrical device can be constructed using the cylindrical battery cells and battery assembly disclosed in this application. This helps to alleviate the problem of connection failures in the electrode components and terminals of the cylindrical battery cells during use, thereby improving the stability and lifespan of the cylindrical battery cells.

[0214] This application provides an electrical device that uses a cylindrical battery cell or battery assembly as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0215] For ease of explanation, the following embodiments will be described using a vehicle as an example of an electrical device according to an embodiment of this application.

[0216] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is installed inside the vehicle 1000. The battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, it can serve as the vehicle's operating power source or general power source. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 controls the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0217] In some embodiments of this application, the battery device 100 can not only serve as the operating power or power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0218] Please refer to Figures 2 and 3. Figure 2 is an exploded view of the structure of a battery device 100 provided in some embodiments of this application, and Figure 3 is a schematic diagram of the structure of a cylindrical battery cell 20 provided in some embodiments of this application. The battery device 100 includes a housing 10 and a cylindrical battery cell 20, which is housed within the housing 10.

[0219] The housing 10 provides an assembly space for the cylindrical battery cell 20, and the housing 10 can adopt various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which overlap each other, and together define an assembly space for accommodating the cylindrical battery cell 20. The second housing body 12 may be a hollow structure with one end open, and the first housing body 11 may be a plate-like structure, with the first housing body 11 covering the open side of the second housing body 12 so that the first housing body 11 and the second housing body 12 together define the assembly space; alternatively, the first housing body 11 and the second housing body 12 may both be hollow structures with one side open, with the open side of the first housing body 11 covering the open side of the second housing body 12.

[0220] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder, a cuboid, or a cube. For example, in Figure 2, the shape of the box 10 is a cuboid.

[0221] In the battery device 100, there can be one or more cylindrical battery cells 20 disposed within the housing 10. When there are multiple cylindrical battery cells 20 disposed within the housing 10, the multiple cylindrical battery cells 20 can be connected in series, in parallel, or in a mixed manner. A mixed connection means that the multiple cylindrical battery cells 20 are connected in both series and parallel. The multiple cylindrical battery cells 20 can be directly connected in series, in parallel, or in a mixed manner, and then the whole assembly of the multiple cylindrical battery cells 20 is housed within the housing 10. Of course, the battery device 100 can also be in the form of multiple cylindrical battery cells 20 first connected in series, in parallel, or in a mixed manner to form a battery module, and then the multiple battery modules are connected in series, in parallel, or in a mixed manner to form a whole assembly, which is then housed within the housing 10.

[0222] In some embodiments, the battery device 100 may also include other structures. For example, the battery device 100 may also include a busbar for connecting a plurality of cylindrical battery cells 20 to achieve electrical connection between the plurality of cylindrical battery cells 20.

[0223] Each cylindrical battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited to these.

[0224] According to some embodiments of this application, referring to Figure 3, and further referring to Figures 4, 5, 6, and 7, Figure 4 is an exploded view of the cylindrical battery cell 20 provided in some embodiments of this application, Figure 5 is a cross-sectional view of the cylindrical battery cell 20 provided in some embodiments of this application, Figure 6 is a partial enlarged view of point A of the cylindrical battery cell 20 shown in Figure 5, and Figure 7 is a schematic diagram of the structure of the first current collector 24 provided in some embodiments of this application. This application provides a cylindrical battery cell 20, which includes a housing 21, electrode terminals 22, an electrode assembly 23, and a first current collector 24. The housing 21 has a wall portion 211, and the thickness direction X of the wall portion is the axial direction of the cylindrical battery cell 20. The electrode terminals 22 are disposed on the wall portion 211. The electrode assembly 23 is accommodated within the housing 21, and the electrode assembly 23 includes a main body portion 231 and a first tab 232, the first tab 232 protruding from the end of the main body portion 231 facing the wall portion 211. The first current collector 24 is housed within the housing 21. The first current collector 24 includes a current collector body region 241, an elastic region 242, and a terminal connection region 243. At least a portion of the current collector body region 241 is disposed between the wall 211 and the first electrode tab 232 in the thickness direction X of the wall. The current collector body region 241 is electrically connected to the first electrode tab 232. The elastic region 242 is connected to the current collector body region 241 and the terminal connection region 243 at opposite ends in its extension direction. The terminal connection region 243 is connected to the electrode terminal 22. The elastic region 242 is configured to deform when the terminal connection region 243 and the current collector body region 241 move closer or further apart along the thickness direction X of the wall.

[0225] The outer shell 21 can also be used to contain electrolytes, such as electrolyte solutions. The outer shell 21 can have various structural forms. The outer shell 21 can also be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0226] The outer casing 21 has a wall portion 211, the thickness direction X of which is the axial direction of the cylindrical battery cell 20. That is, the wall portion 211 is the end wall of the outer casing 21 at one end of the cylindrical battery cell 20 in the axial direction.

[0227] In some embodiments, the housing 21 may include a housing 212 and an end cap 213. The housing 212 has an internal cavity with an opening 2121, i.e., the housing 212 is a hollow structure with one end open. The end cap 213 covers the opening 2121 of the housing 212 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte.

[0228] The housing 212 may include a bottom wall 2122 and a side wall 2123. The side wall 2123 surrounds the bottom wall 2122. One end of the side wall 2123 is connected to the bottom wall 2122, and the other end forms an opening 2121. The end cap 213 is disposed opposite to the bottom wall 2122.

[0229] Optionally, the wall portion 211 on which the electrode terminal 22 is provided can be the bottom wall 2122 of the housing 212 or the end cap 213 of the outer shell 21. For example, in Figures 3 and 4, the wall portion 211 is the bottom wall 2122 of the housing 212. Correspondingly, the electrode terminal 22 is provided on the bottom wall 2122 of the housing 212. The thickness direction of the bottom wall 2122 of the housing 212 is the thickness direction X of the wall portion, and the housing 212 has an opening 2121 at the end of the wall portion away from the electrode terminal 22 in the thickness direction X. Of course, in other embodiments, the wall portion 211 can also be the end cap 213 of the outer shell 21.

[0230] When assembling the cylindrical battery cell 20, the electrode assembly 23 can be placed into the housing 212 first, and the electrolyte can be filled into the housing 212. Then, the end cap 213 can be placed on the opening 2121 of the housing 212 to close the opening 2121 of the housing 212.

[0231] The cylindrical battery cell 20 is cylindrical, and the central axis of the cylindrical battery cell 20 extends along the thickness direction X of the wall. Correspondingly, the side wall 2123 of the housing 212 is also cylindrical, and the central axis of the housing 212 extends along the thickness direction X of the wall, so that the projection of the end cap 213 on the thickness direction X of the wall is circular.

[0232] Understandably, the outer casing 21 is not limited to the structure described above. The outer casing 21 can also be other structures. For example, the outer casing 21 includes a shell 212 and two end caps 213. The shell 212 is a hollow structure with openings 2121 on both sides. One end cap 213 is fitted onto one opening 2121 of the shell 212 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte. That is, the shell 212 of the outer casing 21 only includes side walls 2123. The side walls 2123 are hollow structures with openings 2121 at both ends in the thickness direction X of the wall portion. The two end caps 213 are fitted onto the openings 2121 at both ends of the side walls 2123 in the thickness direction X of the wall portion. Correspondingly, one of the two end caps 213 is the wall portion 211.

[0233] It should be noted that the electrode assembly 23 is the component in the cylindrical battery cell 20 where the electrochemical reaction occurs. The electrode assembly 23 includes a main body 231, a first tab 232, and a second tab 233. The main body 231 is the main component of the electrode assembly 23 in the cylindrical battery cell 20 where the electrochemical reaction occurs, while the first tab 232 and the second tab 233 serve to output or input electrical energy to the electrode assembly 23. The structure of the electrode assembly 23 can be varied. For example, in Figure 4, the electrode assembly 23 may include a positive electrode, a separator, and a negative electrode. The electrode assembly 23 is a wound structure formed by winding the positive electrode, separator, and negative electrode. The main body 231 of the electrode assembly 23 has a cylindrical structure, and the central axis of the main body 231 extends along the thickness direction X of the wall.

[0234] For example, the separator is a separator membrane, and the main material of the separator membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.

[0235] Optionally, the electrode assembly 23 housed within the housing 21 can be one or more. For example, in Figure 4, only one electrode assembly 23 is provided within the housing 21 of the cylindrical battery cell 20. Of course, the structure of the cylindrical battery cell 20 is not limited to this; in other embodiments, the electrode assembly 23 housed within the housing 21 can be two, three, four, five, six, seven, or eight, etc.

[0236] The first electrode 232 and the second electrode 233 have opposite polarities. In Figures 4 and 5, the first electrode 232 and the second electrode 233 are respectively connected to the two ends of the main body 231 in the thickness direction X of the wall. In the thickness direction X of the wall, the first electrode 232 protrudes from the end of the main body 231 facing the wall 211, and the second electrode 233 protrudes from the end of the main body 231 away from the wall 211.

[0237] It should be noted that if the first tab 232 is the positive tab of the electrode assembly 23, then the first tab 232 is a component formed by stacking and connecting the regions on the positive electrode sheet that are not coated with the positive active material layer. Correspondingly, if the second tab 233 is the negative tab of the electrode assembly 23, then the second tab 233 is a component formed by stacking and connecting the regions on the negative electrode sheet that are not coated with the negative active material layer. Conversely, if the first tab 232 is the negative tab of the electrode assembly 23, then the first tab 232 is a component formed by stacking and connecting the regions on the negative electrode sheet that are not coated with the negative active material layer. Correspondingly, if the second tab 233 is the positive tab of the electrode assembly 23, then the second tab 233 is a component formed by stacking and connecting the regions on the positive electrode sheet that are not coated with the positive active material layer.

[0238] It should be noted that the positive electrode sheet includes a positive current collector, which includes a positive electrode coated area and a positive electrode blank area arranged and connected along the thickness direction X of the wall. The positive electrode coated area is coated with a positive active material layer on at least one side of its thickness direction, that is, the positive electrode coated area of ​​the positive current collector is coated with a positive active material layer, while the positive electrode blank area of ​​the positive current collector is not coated with a positive active material layer. Correspondingly, the positive electrode blank area includes a positive electrode transition area and at least one positive electrode tab area. The positive electrode transition area is connected to the positive electrode coated area, and at least one positive electrode tab area is arranged at intervals along the winding direction of the positive electrode sheet. The positive electrode tab area is connected to the end of the positive electrode transition area away from the positive electrode coated area in the thickness direction X of the wall. In the winding direction of the positive electrode sheet, the length dimension of the positive electrode transition area is the same as the length dimension of the positive electrode coated area. When the positive electrode sheet and the negative electrode sheet are wound together... After forming the electrode assembly 23, at least one positive electrode tab region is formed into a first tab 232 or a second tab 233 by a process such as kneading or smoothing. Optionally, in some embodiments, an insulating layer or other coating may be coated on the positive electrode transition region, and the insulating layer is located at the edge of one end of the positive electrode active material layer in the thickness direction X of the wall. In some embodiments, the insulating layer may also be a structure that is partially coated on the positive electrode tab region near the positive electrode transition region, that is, part of the insulating layer is coated on the positive electrode transition region and part of the insulating layer is coated on the positive electrode tab region. Of course, in other embodiments, the positive electrode blank region may not be provided with a positive electrode transition region. Correspondingly, the positive electrode tab region and the positive electrode coating region are directly connected. In this embodiment, the positive electrode active material layer may also be a structure that is partially coated on the positive electrode tab region near the positive electrode coating region.Similarly, the negative electrode sheet includes a negative electrode current collector, which includes negative electrode coated areas and negative electrode blank areas arranged and connected along the thickness direction X of the wall. The negative electrode coated areas are coated with a negative electrode active material layer on at least one side of their thickness direction; that is, the negative electrode coated areas of the negative electrode current collector are coated with a negative electrode active material layer, while the negative electrode blank areas of the negative electrode current collector are not coated with a negative electrode active material layer. Correspondingly, the negative electrode blank area includes a negative electrode transition area and at least one negative electrode tab area. The negative electrode transition area is connected to the negative electrode coated area, and at least one negative electrode tab area is arranged at intervals along the winding direction of the negative electrode sheet. The negative electrode tab area is connected to the end of the negative electrode transition area in the thickness direction X of the wall that is away from the negative electrode coated area. In the winding direction of the negative electrode sheet, the length of the negative electrode transition area is the same as the length of the negative electrode coated area. The positive electrode sheet and the negative electrode sheet are wound together to form... After electrode assembly 23, at least one negative electrode tab region is formed into a first tab 232 or a second tab 233 by a process such as kneading or smoothing. Optionally, in some embodiments, an insulating layer or other coating may be coated on the negative electrode transition region, and the insulating layer is located at the edge of one end of the negative electrode active material layer in the thickness direction X of the wall. In some embodiments, the insulating layer may also be a structure that is partially coated on the negative electrode tab region near the negative electrode transition region, that is, part of the insulating layer is coated on the negative electrode transition region and part of the insulating layer is coated on the negative electrode tab region. Of course, in other embodiments, the negative electrode blank region may not be provided with a negative electrode transition region. Correspondingly, the negative electrode tab region and the negative electrode coating region are directly connected. In this embodiment, the negative electrode active material layer may also be a structure that is partially coated on the negative electrode tab region near the negative electrode coating region. Correspondingly, the positive electrode coating area and positive electrode transition area of ​​the positive electrode current collector, the negative electrode coating area and negative electrode transition area of ​​the negative electrode current collector, and the separator are wound together to form the main body 231 of the electrode assembly 23, so that the first electrode tab 232 and the second electrode tab 233 are respectively protruding at both ends of the main body 231 in the thickness direction X of the wall portion. It should be noted that in a structure where no positive transition region is provided in the positive blank area of ​​the positive current collector, the main body 231 of the electrode assembly 23 is formed by the positive coating area of ​​the positive current collector, the negative coating area and the negative transition region of the negative current collector, and the separator being wound together; in a structure where no negative transition region is provided in the negative blank area of ​​the negative current collector, the main body 231 of the electrode assembly 23 is formed by the positive coating area and the positive transition region of the positive current collector, the negative coating area of ​​the negative current collector, and the separator being wound together; if no positive transition region is provided in the positive blank area of ​​the positive current collector and no negative transition region is provided in the negative blank area of ​​the negative current collector, the main body 231 of the electrode assembly 23 is formed by the positive coating area of ​​the positive current collector, the negative coating area of ​​the negative current collector, and the separator being wound together.

[0239] For example, the first electrode tab 232 is a positive electrode tab, that is, the first electrode tab 232 is a component formed by at least one positive electrode tab area of ​​the positive electrode sheet after the positive electrode sheet and the negative electrode sheet are wound together to form the electrode assembly 23, and then formed by a flattening or smoothing process, etc. Correspondingly, the second electrode tab 233 is a negative electrode tab, that is, the second electrode tab 233 is a component formed by at least one negative electrode tab area of ​​the negative electrode sheet after the positive electrode sheet and the negative electrode sheet are wound together to form the electrode assembly 23, and then formed by a flattening or smoothing process, etc.

[0240] It should be noted that the positive electrode tab region formed by the positive electrode blank area of ​​the positive electrode sheet can be one or more. If there are multiple positive electrode tab regions formed by the positive electrode blank area, they are arranged at intervals along the winding direction of the positive electrode sheet; if there is only one positive electrode tab region formed by the positive electrode blank area, it is arranged continuously along the winding direction of the positive electrode sheet. Similarly, the negative electrode tab region formed by the negative electrode blank area of ​​the negative electrode sheet can be one or more. If there are multiple negative electrode tab regions formed by the negative electrode blank area, they are arranged at intervals along the winding direction of the negative electrode sheet; if there is only one negative electrode tab region formed by the negative electrode blank area, it is arranged continuously along the winding direction of the negative electrode sheet.

[0241] In this embodiment, the electrode terminal 22 serves to input or output electrical energy to the cylindrical battery cell 20, that is, the electrode terminal 22 acts as an output electrode of the cylindrical battery cell 20. Exemplarily, the electrode terminal 22 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy.

[0242] The electrode terminal 22 is insulatedly mounted on the wall portion 211, meaning that no electrical connection is formed between the electrode terminal 22 and the wall portion 211. As shown in Figure 5, the electrode terminal 22 is riveted to the wall portion 211. The wall portion 211 is provided with a mounting hole 2111, which extends through both sides of the wall portion 211 along the thickness direction X. A portion of the electrode terminal 22 passes through the mounting hole 2111. The electrode terminal 22 has a first limiting portion 2211 located on the side of the wall portion 211 facing the electrode assembly 23 and a second limiting portion 2212 located on the side of the wall portion 211 away from the electrode assembly 23. At least a portion of the wall portion 211 is located between the first limiting portion 2211 and the second limiting portion 2212 in the thickness direction X of the wall portion, so that the first limiting portion 2211 and the second limiting portion 2212 can cooperate to clamp the wall portion 211, thereby achieving the riveting of the electrode terminal 22 to the wall portion 211. Of course, in other embodiments, the electrode terminal 22 may also be a structure that is snapped or bonded to the wall portion 211.

[0243] In Figure 6, the cylindrical battery cell 20 is also provided with a sealing member 25. The sealing member 25 is disposed between the electrode terminal 22 and the wall portion 211. The sealing member 25 is configured to seal the gap between the electrode terminal 22 and the wall surface of the mounting hole 2111. A portion of the sealing member 25 is located inside the mounting hole 2111 and between the electrode terminal 22 and the wall surface of the mounting hole 2111. A portion of the sealing member 25 is located between the first limiting portion 2211 and the wall portion 211 in the thickness direction X of the wall portion, and a portion of the sealing member 25 is located between the second limiting portion 2212 and the wall portion 211 in the thickness direction X of the wall portion.

[0244] The sealing element 25 is made of insulating material, and the sealing element 25 is also configured to insulate and isolate the electrode terminal 22 and the wall portion 211, so that the electrode terminal 22 is insulated and installed on the wall portion 211.

[0245] In this embodiment, the first current collector 24 serves as the first tab 232 connecting the electrode terminal 22 and the electrode assembly 23 to achieve electrical connection between the electrode terminal 22 and the electrode assembly 23. The material of the first current collector 24 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0246] Optionally, the connection structure between the first electrode tab 232 and the first current collector 24, and between the first current collector 24 and the electrode terminal 22, can be various, such as welding or bonding. For example, the first electrode tab 232 is welded to the first current collector 24, and the first current collector 24 is welded to the electrode terminal 22, for example, by laser welding or ultrasonic welding.

[0247] The first current collector 24 includes a current collector body area 241, an elastic area 242, and a terminal connection area 243. The current collector body area 241 is disposed between the wall portion 211 and the first electrode 232 in the thickness direction X of the wall portion, and the current collector body area 241 is electrically connected to the first electrode 232. That is, the first current collector 24 has a current collector body area 241 located between the wall portion 211 and the first electrode 232 in the thickness direction X of the wall portion, and the current collector body area 241 serves to be electrically connected to the first electrode 232.

[0248] It should be noted that the current collector body region 241 can be a structure directly connected to the first electrode 232 or an indirectly connected structure. For example, referring to Figure 7, the first current collector component 24 may further include an electrode connection region 244, which is connected to the current collector body region 241 and connected to the first electrode 232 to electrically connect the first electrode 232 and the current collector body region 241. For example, the electrode connection region 244 is welded to the first electrode 232.

[0249] The terminal connection area 243 is connected to the electrode terminal 22. That is, the first current collector 24 has a structure in which the terminal connection area 243 and the electrode terminal 22 are connected to each other, such as by welding or bonding.

[0250] For example, the terminal connection area 243 is connected to the end face of the electrode terminal 22 near the main body portion 231 in the thickness direction X of the wall portion.

[0251] The elastic region 242 is connected to the current collection body region 241 and the terminal connection region 243 at opposite ends in its extending direction, respectively. That is, the current collection body region 241 and the terminal connection region 243 of the first current collection member 24 are interconnected by the elastic region 242. One end of the elastic region 242 is connected to the current collection body region 241, and the other end is connected to the terminal connection region 243. The elastic region 242 is a strip-shaped structure connecting the current collection body region 241 and the terminal connection region 243, so that the elastic region 242 is configured to be able to approach the terminal connection region 243 and the wall portion 211. The elastic zone 242 can deform when the first current collector 24 is compressed or stretched in the thickness direction X of the wall, so that the current collector body area 241 and the terminal connection area 243 move closer or further apart. It should be noted that when the elastic zone 242 deforms, it can be elastic deformation, plastic deformation, or both. It should be noted that when the elastic zone 242 is subjected to external force and deforms, elastic deformation occurs first, and plastic deformation occurs when the force exceeds the elastic limit of the elastic zone 242.

[0252] Optionally, the number of elastic regions 242 connected between the current collection body area 241 and the terminal connection area 243 can be one or more.

[0253] It should be noted that the first tab 232 and the second tab 233 have opposite polarities. The electrode terminal 22 is electrically connected to the first tab 232 through the first current collector 24, so that the electrode terminal 22 serves as one output electrode of the cylindrical battery cell 20. Optionally, the second tab 233 can be a structure electrically connected to the housing 21, so that the housing 21 serves as another output electrode of the cylindrical battery cell 20. Of course, two electrode terminals 22 can also be insulatedly installed on the housing 21, and the two electrode terminals 22 are electrically connected to the first tab 232 and the second tab 233 respectively, so that the two electrode terminals 22 serve as two output electrodes of the cylindrical battery cell 20.

[0254] For example, in FIG5, the second tab 233 is electrically connected to the side wall 2123 of the housing 212, so that the side wall 2123 serves as another output pole of the cylindrical battery cell 20. Of course, in the embodiment where the second tab 233 is electrically connected to the housing 21, the second tab 233 may also be a structure electrically connected to the bottom wall 2122 of the housing 212 or the end cap 213 of the housing 21.

[0255] In some embodiments, as shown in Figures 4 and 5, the cylindrical battery cell 20 may further include a second current collector 26 located at one end of the electrode assembly 23 away from the wall portion 211 in the thickness direction X of the wall portion. The second current collector 26 connects the second tab 233 and the housing 21 to electrically connect the electrode assembly 23 and the housing 21.

[0256] The housing 212 has a protrusion 2123a on its side wall 2123. The second current collector 26 connects the protrusion 2123a and the second tab 233 to achieve an electrical connection between the second tab 233 and the housing 21. For example, the protrusion 2123a is an annular structure extending circumferentially along the cylindrical battery cell 20. Optionally, the side wall 2123 is also provided with a groove 2123b opposite to the surface of the electrode assembly 23 and corresponding to the position of the protrusion 2123a. The groove 2123b is also an annular groove extending circumferentially along the cylindrical battery cell 20, which facilitates the stamping of the protrusion 2123a on the side wall 2123, reducing the processing difficulty of the protrusion 2123a.

[0257] Optionally, the connection structure between the second current collector 26 and the second tab 233, and between the second current collector 26 and the housing 21, can be various, such as welding or bonding. For example, the second tab 233 is welded to the second current collector 26, and the second current collector 26 is welded to the housing 21, for example, by laser welding or ultrasonic welding.

[0258] For example, the material of the second current collector 26 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0259] It should be noted that in other embodiments, the second tab 233 of the electrode assembly 23 may also be a structure that is directly connected to the housing 21, such as by welding or bonding.

[0260] In some embodiments, as shown in Figures 4 and 6, the cylindrical battery cell 20 may further include a first insulating member 27. Along the thickness direction X of the wall portion, the first insulating member 27 includes a first insulating portion 271 located between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion. The first insulating portion 271 is configured to insulate and isolate the wall portion 211 and the first current collector 24, such that the first current collector 24 is disposed between the first insulating portion 271 and the first tab 232 in the thickness direction X of the wall portion.

[0261] In some embodiments, the cylindrical battery cell 20 may further include a pressure relief component disposed on the housing 21, which is used to release the internal pressure of the cylindrical battery cell 20 when the internal pressure or temperature of the cylindrical battery cell 20 reaches a predetermined value.

[0262] The pressure relief component can be located on the end cap 213 of the outer casing 21 or on the housing 212. Similarly, the pressure relief component and the outer casing 21 can be integrally formed or separate components. If the pressure relief component and the outer casing 21 are integrally formed, the pressure relief component is a region on the outer casing 21 with a weak structure. For example, the outer casing 21 has a pressure relief groove, and the outer casing 21 is configured to split along at least a portion of the pressure relief groove when the cylindrical battery cell 20 is depressurized, thereby releasing the internal pressure of the cylindrical battery cell 20. In other embodiments, the pressure relief component and the outer casing 21 can also be separate components. The pressure relief component can be connected to the outer casing 21 by welding or other means. Correspondingly, the pressure relief component can be a component such as an explosion-proof valve, explosion-proof disc, gas valve, pressure relief valve, or safety valve.

[0263] In this embodiment, the first current collector 24 is provided with a current collector body area 241, an elastic area 242, and a terminal connection area 243. The current collector body area 241 is electrically connected to the first electrode tab 232, and the terminal connection area 243 is connected to the electrode terminal 22. By setting the elastic area 242 to have its two ends connected to the current collector body area 241 and the terminal connection area 243 respectively in its extension direction, the elastic area 242 is a strip structure connecting the current collector body area 241 and the terminal connection area 243. This allows the elastic area 242 to have the ability to deform while realizing the electrical connection between the electrode terminal 22 and the electrode assembly 23. This allows the elastic area 242 to deform when the terminal connection area 243 and the current collector body area 241 move closer or further away from each other along the thickness direction X of the wall. On the one hand, this allows the terminal connection area 242 to deform. When subjected to compression or other phenomena, the sub-connection area 243 can move along the thickness direction X of the wall, thereby absorbing the assembly error between the electrode terminal 22 and the terminal connection area 243, which is beneficial to improving the assembly quality between the electrode terminal 22 and the terminal connection area 243. On the other hand, the elastic area 242 can play a certain buffering role between the current collector body area and the terminal connection area 243, thereby alleviating the rigid tension between the current collector body area and the terminal connection area 243, between the terminal connection area 243 and the electrode terminal 22, and between the current collector body area and the first tab 232 during the shaking or displacement of the electrode assembly 23. This is beneficial to reducing the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23, and also to reducing the phenomenon of the first current collector 24 being damaged by tension, thereby effectively improving the stability and service life of the cylindrical battery cell 20.

[0264] According to some embodiments of this application, referring to Figures 6 and 7, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projection of the terminal connection area 243 and the orthographic projection of the current collection body area 241 do not overlap. That is, the projection of the terminal connection area 243 in the thickness direction X of the wall does not fall into the current collection body area 241.

[0265] For example, the current collector body area 241 is an annular structure surrounding the terminal connection area 243, and the terminal connection area 243 is spaced apart from the current collector body area 241 in the radial direction of the cylindrical battery cell 20, so that the projections of the terminal connection area 243 and the current collector body area 241 in the thickness direction X of the wall do not overlap. Correspondingly, the elastic area 242 connects the terminal connection area 243 and the current collector body area 241. The radial direction of the cylindrical battery cell 20 is perpendicular to the thickness direction X of the wall, and the radial direction of the cylindrical battery cell 20 is within the projection plane perpendicular to the thickness direction X of the wall. The outer peripheral surface of the cylindrical battery cell 20 points towards the central axis of the cylindrical battery cell 20, or the central axis of the cylindrical battery cell 20 points towards the outer peripheral surface of the cylindrical battery cell 20.

[0266] In this embodiment, by setting the terminal connection area 243 and the current collector body area 241 to a structure in which their projections in the thickness direction X of the wall do not overlap, the obstruction and interference effect of the current collector body area 241 on the terminal connection area 243 can be reduced when the terminal connection area 243 is close to or far away from the current collector body area 241 in the thickness direction X of the wall. This is beneficial to expanding the range of movement of the terminal connection area 243 relative to the current collector body area 241 in the thickness direction X of the wall. This can further improve the deformation degree of the elastic area 242 in the thickness direction X of the wall, thereby further improving the effect of the elastic area 242 in absorbing the assembly error between the electrode terminal 22 and the terminal connection area 243, so as to further improve the assembly quality between the electrode terminal 22 and the terminal connection area 243, and further improve the buffering effect of the elastic area 242 between the current collector body area and the terminal connection area 243, so as to further reduce the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23.

[0267] According to some embodiments of this application, referring to FIG7, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projection of the elastic region 242 and the orthographic projection of the current collection body region 241 do not overlap. That is, the projection of the elastic region 242 in the thickness direction X of the wall does not fall into the current collection body region 241.

[0268] For example, the current collector body area 241 is an annular structure surrounding the terminal connection area 243. The terminal connection area 243 is spaced apart from the current collector body area 241 in the radial direction of the cylindrical battery cell 20. The elastic area 242 is connected at both ends in its extension direction to the outer peripheral surface of the terminal connection area 243 and the inner peripheral surface of the current collector body area 241, respectively, so as to realize that the projections of the elastic area 242 and the current collector body area 241 in the thickness direction X of the wall do not overlap.

[0269] It should be noted that the elastic region 242 and the main flow collection region 241 can be directly connected, that is, one end of the elastic region 242 in its extension direction is directly connected to the inner circumferential surface of the main flow collection region 241. Of course, the elastic region 242 and the main flow collection region 241 can be indirectly connected. For example, in Figure 7, the first flow collection component 24 can also include a base region 245, and the elastic region 242 is a structure that is connected to the inner circumferential surface of the main flow collection region 241 through the base region 245.

[0270] In this embodiment, by setting the elastic region 242 and the current collector body region 241 to a structure in which their projections in the thickness direction X of the wall do not overlap, the obstruction and interference of the current collector body region 241 on the elastic region 242 can be reduced when the terminal connection region 243 and the current collector body region 241 move closer or further away from each other along the thickness direction X of the wall, causing the elastic region 242 to deform. This allows the elastic region 242 to deform better during assembly or use, which is beneficial to expanding the degree of deformation of the elastic region 242 in the thickness direction X of the wall. This further enhances the effect of the elastic region 242 in absorbing assembly errors between the electrode terminal 22 and the terminal connection region 243, thereby further improving the assembly quality between the electrode terminal 22 and the terminal connection region 243. It also further enhances the buffering effect of the elastic region 242 between the current collector body region and the terminal connection region 243, thereby further reducing the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23.

[0271] According to some embodiments of this application, please refer to Figures 6 and 7. The electrode terminal 22 and the terminal connection area 243 are arranged along the thickness direction X of the wall. Along the thickness direction X of the wall, the terminal connection area 243 has a first surface 2431 facing away from the main body 231. The electrode terminal 22 has a connection surface 223 facing the main body 231. The connection surface 223 is connected to the first surface 2431.

[0272] The electrode terminal 22 and the terminal connection area 243 are arranged and connected along the thickness direction X of the wall, such that the end of the electrode terminal 22 near the main body 231 in the thickness direction X of the wall is connected to the terminal connection area 243. Correspondingly, the first surface 2431 of the terminal connection area 243 is both the surface of the terminal connection area 243 facing the electrode terminal 22 in the thickness direction X of the wall and the surface on which the terminal connection area 243 and the electrode terminal 22 are connected to each other.

[0273] The second surface 2411 of the current collecting main body region 241 is the surface of the current collecting main body region 241 facing the wall portion 211 in the thickness direction X of the wall portion. In the embodiment where the first insulating portion 271 is provided between the first current collecting member 24 and the wall portion 211, the current collecting main body region 241 abuts against the first insulating portion 271 and the first electrode tab 232 in the thickness direction X of the wall portion. Correspondingly, the second surface 2411 of the current collecting main body region 241 abuts against the first insulating portion 271.

[0274] The connecting surface 223 is connected to the first surface 2431, that is, the end of the electrode terminal 22 near the main body 231 in the thickness direction X of the wall is connected to the side of the terminal connecting area 243 away from the main body 231. For example, the connecting surface 223 and the first surface 2431 are welded together to form the connecting portion 28.

[0275] Optionally, the connecting surface 223 of the electrode terminal 22 and the first surface 2431 of the terminal connection area 243 are parallel and fit together, and both the connecting surface 223 of the electrode terminal 22 and the first surface 2431 of the terminal connection area 243 are perpendicular to the thickness direction X of the wall.

[0276] In this embodiment, by arranging the electrode terminal 22 and the terminal connection area 243 along the thickness direction X of the wall, and connecting the first surface 2431 of the terminal connection area 243 away from the main body 231 to the connection surface 223 of the electrode terminal 22 facing the main body 231, the assembly difficulty between the electrode terminal 22 and the terminal connection area 243 can be reduced, and the connection stability and overcurrent stability between the terminal connection area 243 and the electrode terminal 22 can be improved. On the other hand, under the action of the elastic area 242, the assembly error between the electrode terminal 22 and the terminal connection area 243 can be absorbed, thereby improving the assembly quality between the terminal connection area 243 and the electrode terminal 22.

[0277] According to some embodiments of this application, please continue to refer to Figures 6 and 7. Along the thickness direction X of the wall portion, the current collecting main body region 241 has a second surface 2411 facing away from the main body portion 231, and the second surface 2411 is further away from the main body portion 231 than the first surface 2431. That is, the electrode terminal 22 is a structure in which the terminal connection region 243 is pressed down towards the main body portion 231 in the thickness direction X of the wall portion, such that the side of the terminal connection region 243 facing away from the main body portion 231 is recessed towards the main body portion 231 compared to the side of the current collecting main body region 241 facing away from the main body portion 231.

[0278] The second surface 2411 of the current collecting main body region 241 is the surface of the current collecting main body region 241 facing the wall portion 211 in the thickness direction X of the wall portion, and is also the surface of the current collecting main body region 241 facing the first insulating portion 271 in the thickness direction X of the wall portion. For example, the second surface 2411 of the current collecting main body region 241 abuts against the sixth surface 2712 of the first insulating portion 271.

[0279] In this embodiment, by setting the second surface 2411 of the current collector 241 away from the main body 231 to be further away from the main body 231 in the thickness direction X of the wall than the first surface 2431 of the terminal connection area 243 connecting the electrode terminal 22, the electrode terminal 22 is structured to press down on the terminal connection area 243 in the thickness direction X of the wall towards the main body 231. On the one hand, this can reduce the assembly gap between the first surface 2431 of the terminal connection area 243 and the connection surface 223 of the electrode terminal 22, which is beneficial to further improve the assembly quality between the terminal connection area 243 and the electrode terminal 22. On the other hand, it can also realize that the connection surface 223 of the electrode terminal 22 is closer to the main body 231 in the thickness direction X of the wall than the second surface 2411. This also enables the electrode terminal 22 and the current collector 241 to share a portion of the space in the thickness direction X of the wall, which is beneficial to improve the internal space utilization of the cylindrical battery cell 20.

[0280] In some embodiments, as shown in Figures 6 and 7, along the thickness direction X of the wall portion, the terminal connection area 243 has a third surface 2432 facing the main body portion 231, and the current collection main body area 241 has a fourth surface 2412 facing the main body portion 231, the fourth surface 2412 being further away from the main body portion 231 than the third surface 2432.

[0281] In this embodiment, by further configuring the third surface 2432 of the terminal connection area 243 facing the main body 231 to be closer to the main body 231 in the thickness direction X of the wall portion than the fourth surface 2412 of the current collecting main body area 241 facing the main body 231, the terminal connection area 243 is a structure that is generally sunken towards the main body 231 in the thickness direction X of the wall portion compared to the current collecting main body area 241. This can further improve the effect of the electrode terminal 22 pressing the terminal connection area 243, thereby reducing the assembly gap between the first surface 2431 of the terminal connection area 243 and the connection surface 223 of the electrode terminal 22, which is beneficial to further improve the assembly quality between the terminal connection area 243 and the electrode terminal 22.

[0282] In some embodiments, referring to Figures 6 and 7, and further referring to Figure 8, Figure 8 is a partial cross-sectional view of the electrode assembly 23 of a cylindrical battery cell 20 provided in some embodiments of this application. The first tab 232 has a fifth surface 2321 facing the first current collector 24 in the thickness direction X of the wall portion. The current collector body region 241 abuts against the fifth surface 2321, and the fifth surface 2321 is provided with a relief portion 2322 recessed in the thickness direction X of the wall portion away from the electrode terminal 22. At least a portion of the terminal connection region 243 is located within the relief portion 2322 along the thickness direction X of the wall portion. That is, at least a portion of the terminal connection region 243 is accommodated within the relief portion 2322 along the thickness direction X of the wall portion.

[0283] It should be noted that the terminal connection area 243 can be a structure in which the entire wall thickness direction X is located within the clearance portion 2322, or it can be a structure in which it is only partially located within the clearance portion 2322.

[0284] Optionally, the clearance portion 2322 may be a groove structure or a hole structure provided on the fifth surface 2321 of the first tab 232.

[0285] In this embodiment, by setting at least a portion of the terminal connection area 243 in the thickness direction X of the wall to be accommodated within the clearance portion 2322 of the first tab 232, at least a portion of the terminal connection area 243 is accommodated within the clearance portion 2322. The cylindrical battery cell 20 with this structure can achieve the first tab 232 to avoid the terminal connection area 243, while also enabling the terminal connection area 243 and the first tab 232 to share a portion of the space in the thickness direction X of the wall, which is beneficial to improving the internal space utilization of the cylindrical battery cell 20.

[0286] Of course, the structure of the cylindrical battery cell 20 is not limited to this. In some embodiments, the cylindrical battery cell 20 can also have other structures. For example, along the thickness direction X of the wall, the current collector main region 241 has a second surface 2411 facing away from the main body 231, and the second surface 2411 is closer to the main body 231 than the first surface 2431. That is, the terminal connection region 243 has a structure that is raised in the thickness direction X of the wall relative to the current collector main region 241 towards the wall 211.

[0287] In this embodiment, by setting the second surface 2411 of the current collection main body region 241 away from the main body 231 to be closer to the main body 231 in the thickness direction X of the wall than the first surface 2431 of the terminal connection region 243 away from the main body 231, the first surface 2431 of the terminal connection region 243 can be closer to the connection surface 223 of the electrode terminal 22 in the thickness direction X of the wall than the second surface 2411 of the current collection main body region 241. On the one hand, this facilitates the assembly and connection between the first surface 2431 of the terminal connection region 243 and the connection surface 223 of the electrode terminal 22, and can better absorb the assembly error between the electrode terminal 22 and the terminal connection region 243. On the other hand, it allows the electrode terminal 22 to press the terminal connection region 243 better in the thickness direction X of the wall towards the main body 231, which helps to reduce the assembly gap between the first surface 2431 of the terminal connection region 243 and the connection surface 223 of the electrode terminal 22, thereby effectively improving the assembly quality between the terminal connection region 243 and the electrode terminal 22.

[0288] According to some embodiments of this application, as shown in Figures 5 and 6, at least a portion of the elastic region 242 deforms and bends.

[0289] For example, the elastic region 242 is partially deformed and bent, and the second surface 2411 is further away from the main body 231 in the thickness direction X of the wall than the first surface 2431. That is, the electrode terminal 22 is structured to press the terminal connection region 243 down along the thickness direction X of the wall towards the main body 231, so that the elastic region 242 is structured to deform and bend along the thickness direction X of the wall towards the main body 231, so that the first surface 2431 of the terminal connection region 243 is further away from the main body 231 in the thickness direction X of the wall than the current collector. The second surface 2411 of the main body region 241 is closer to the main body portion 231, resulting in a height difference between the terminal connection region 243 and the current collecting main body region 241 in the thickness direction X of the wall portion. This also causes the electrode terminal 22 and the current collecting main body region 241 to share a portion of the space in the thickness direction X of the wall portion. In embodiments where the current collecting main body region 241 is an annular structure surrounding the terminal connection region 243, an inner peripheral hole is formed on the inner side of the current collecting main body region 241. Correspondingly, a portion of the electrode terminal 22 extends into the inner peripheral hole along the thickness direction X of the wall portion. Of course, in embodiments where the second surface 2411 is closer to the main body portion 231 in the thickness direction X of the wall portion than the first surface 2431, the elastic region 242 is a structure that deforms and bends in the direction away from the main body portion 231 along the thickness direction X of the wall portion.

[0290] In this embodiment, by setting the elastic region 242 to at least partially bent and deformed, the elastic region 242 is in a state of accumulating elastic force after the electrode terminal 22 presses the terminal connection region 243. This allows the elastic region 242 to press the first surface 2431 of the terminal connection region 243 onto the connection surface 223 of the electrode terminal 22 along the thickness direction X of the wall. This further reduces the assembly gap between the first surface 2431 of the terminal connection region 243 and the connection surface 223 of the electrode terminal 22, which is beneficial to further improve the assembly quality between the terminal connection region 243 and the electrode terminal 22.

[0291] According to some embodiments of this application, referring to Figures 6, 7 and 8, along the thickness direction X of the wall portion, the first electrode tab 232 has a fifth surface 2321 facing the wall portion 211, and the current collection body region 241 abuts against the fifth surface 2321. The fifth surface 2321 is provided with a relief portion 2322 that is recessed in the thickness direction X of the wall portion away from the electrode terminal 22, and the projection of the terminal connection region 243 in the thickness direction X of the wall portion is located within the relief portion 2322.

[0292] The fifth surface 2321 is the surface of the first electrode 232 on the side away from the main body 231 in the thickness direction X of the wall portion, and the fifth surface 2321 abuts against the main body area 241 of the first current collector 24 in the thickness direction X of the wall portion.

[0293] The fifth surface 2321 is provided with a relief portion 2322 that is recessed in the thickness direction X of the wall portion away from the electrode terminal 22, and the projection of the terminal connection area 243 in the thickness direction X of the wall portion is located within the relief portion 2322. That is, the fifth surface 2321 is provided with a relief structure for avoiding the terminal connection area 243 in the thickness direction X of the wall portion corresponding to the position of the terminal connection area 243, and the projection of the terminal connection area 243 in the thickness direction X of the wall portion is located within the relief portion 2322.

[0294] Optionally, the structure of the clearance portion 2322 provided on the fifth surface 2321 can be various. For example, the clearance portion 2322 can be a groove structure provided on the fifth surface 2321, or a hole structure provided on the fifth surface 2321 and penetrating the first electrode tab 232 along the thickness direction X of the wall.

[0295] In this embodiment, by providing a clearance portion 2322 on the fifth surface 2321 of the first tab 232 facing the wall portion 211 and abutting against the current collector body area 241, and by setting the projection of the terminal connection area 243 in the thickness direction X of the wall portion to be located within the clearance portion 2322, the terminal connection area 243 is configured to correspond to the clearance portion 2322 of the first tab 232 in the thickness direction X of the wall portion. This allows the terminal connection area 243 to be inserted into the clearance portion 2322 when it is close to or far from the current collector body area 241 in the thickness direction X of the wall portion, thereby realizing the connection between the first tab 232 and the terminal. The avoidance of the connection area 243 can, on the one hand, reduce the obstruction and interference of the first electrode tab 232 on the terminal connection area 243, which is conducive to expanding the range of movement of the terminal connection area 243 relative to the current collection body area 241 in the thickness direction X of the wall, thereby further improving the deformation degree of the elastic area 242 in the thickness direction X of the wall. On the other hand, it can alleviate the phenomenon of the terminal connection area 243 pressing down on the first electrode tab 232 during use or assembly, which is conducive to reducing the phenomenon of the first electrode tab 232 being damaged, and can reduce the risk of short circuit caused by the first electrode tab 232 being inserted backward into the body part 231.

[0296] In some embodiments, as shown in Figures 6, 7, and 8, at least a portion of the terminal connection area 243 is accommodated within the clearance portion 2322 along the thickness direction X of the wall. That is, at least a portion of the terminal connection area 243 is inserted into the clearance portion 2322 along the thickness direction X of the wall.

[0297] Optionally, along the thickness direction X of the wall, the terminal connection area 243 may be entirely contained within the clearance portion 2322, or it may be only partially contained within the clearance portion 2322.

[0298] In this embodiment, by setting at least a portion of the terminal connection area 243 to be accommodated within the clearance portion 2322 in the thickness direction X of the wall, at least a portion of the terminal connection area 243 is inserted into the clearance portion 2322. The cylindrical battery cell 20 with this structure can achieve the first tab 232 to avoid the terminal connection area 243, while also enabling the terminal connection area 243 and the first tab 232 to share a portion of the space in the thickness direction X of the wall, which is beneficial to improving the internal space utilization of the cylindrical battery cell 20.

[0299] According to some embodiments of this application, referring to Figures 6, 7, and 8, at least a portion of the projection of the elastic region 242 is located within the clearance portion 2322 along the thickness direction X of the wall. That is, at least a portion of the elastic region 242 is a structure corresponding to the clearance portion 2322 in the thickness direction X of the wall.

[0300] Optionally, the elastic zone 242 may be entirely located within the clearance portion 2322, or only a portion of the projection of the wall portion in the thickness direction X may be located within the clearance portion 2322.

[0301] In this embodiment, by setting at least a portion of the projection of the elastic region 242 onto the thickness direction X of the wall portion to be located within the clearance portion 2322, the elastic region 242 is configured such that at least a portion of the clearance portion 2322 of the first electrode 232 corresponds to the clearance portion 2322 of the first electrode 232 on the thickness direction X of the wall portion. This allows the first electrode 232 to clearance at least a portion of the elastic region 242 when the elastic region 242 deforms along the thickness direction X of the wall portion. On the one hand, this reduces the obstruction and interference of the first electrode 232 onto the elastic region 242, which is beneficial for expanding the deformation range of the elastic region 242. On the other hand, it alleviates the phenomenon of the elastic region 242 pressing down on the first electrode 232 during use or assembly, which is beneficial for reducing the phenomenon of damage to the first electrode 232. It also reduces the risk of short circuit caused by the first electrode 232 being inserted backward into the main body portion 231.

[0302] In some embodiments, referring to Figures 6 and 8, the clearance portion 2322 has a clearance opening 2322a formed on the fifth surface 2321. The clearance portion 2322 includes a first circumferential surface 2322b surrounding the clearance opening 2322a. Along the thickness direction X of the wall portion, the end of the first circumferential surface 2322b connected to the fifth surface 2321 forms the clearance opening 2322a. The first circumferential surface 2322b is inclined from the clearance opening 2322a towards the central axis of the cylindrical battery cell 20, and the projection of the end of the first circumferential surface 2322b away from the clearance opening 2322a in the thickness direction X of the wall portion is located within the clearance opening 2322a. In the projection plane perpendicular to the thickness direction X of the wall portion, at least a portion of the orthographic projection of the elastic region 242 and the orthographic projection of the first circumferential surface 2322b overlap.

[0303] Among them, the clearance opening 2322a is an open structure formed on the fifth surface 2321 by the clearance part 2322 penetrating through the fifth surface 2321. Along the thickness direction X of the wall part, the end of the first circumferential surface 2322b connected to the fifth surface 2321 forms the clearance opening 2322a. That is to say, the end of the first circumferential surface 2322b near the wall part 211 in the thickness direction X of the wall part extends to the fifth surface 2321 and forms the clearance opening 2322a.

[0304] The first circumferential surface 2322b is inclined from the clearance opening 2322a toward the central axis of the cylindrical battery cell 20. The projection of the end of the first circumferential surface 2322b away from the clearance opening 2322a in the thickness direction X of the wall is located inside the clearance opening 2322a. That is, the first circumferential surface 2322b has a structure with a larger diameter at the end near the wall 211 and a smaller diameter at the end away from the wall 211 in the thickness direction X of the wall. This makes the first circumferential surface 2322b a structure that gradually tilts outward from the end away from the wall 211 and toward the central axis of the cylindrical battery cell 20.

[0305] In the projection plane perpendicular to the thickness direction X of the wall, at least a portion of the orthographic projection of the elastic region 242 and the orthographic projection of the first circumferential surface 2322b overlap. That is, at least a portion of the projection of the elastic region 242 in the thickness direction X of the wall is located within the first circumferential surface 2322b, such that at least a portion of the elastic region 242 is disposed corresponding to the first circumferential surface 2322b in the thickness direction X of the wall.

[0306] In this embodiment, the first peripheral surface 2322b of the clearance portion 2322 is connected to the fifth surface 2321 at one end to form a clearance opening 2322a, and the clearance opening 2322a is located on the fifth surface 2321. By setting the first peripheral surface 2322b to be inclined from the clearance opening 2322a toward the central axis of the cylindrical battery cell 20, the first peripheral surface 2322b is an inclined surface that is larger at the end closer to the fifth surface 2321 and smaller at the end farther away from the fifth surface 2321 in the thickness direction X of the wall portion. The elastic region 242 and the first peripheral surface 2322b are perpendicular to the thickness direction of the wall portion. The orthographic projection in the projection plane to X is set as a structure that at least partially overlaps, such that the first peripheral surface 2322b is a structure that corresponds to the elastic region 242 in the thickness direction X of the wall, so that the first peripheral surface 2322b of the avoidance part 2322 can fit the deformation of the elastic region 242, so that the avoidance part 2322 can avoid the elastic region 242, and can further expand the avoidance range of the avoidance part 2322 to the elastic region 242 without excessively reducing the first electrode tab 232, thereby further improving the avoidance effect of the avoidance part 2322 to the elastic region 242 while meeting the overcurrent requirements of the first electrode tab 232.

[0307] In some embodiments, as shown in FIG8, the first circumferential surface 2322b is a conical surface.

[0308] In this embodiment, by setting the first circumferential surface 2322b as a conical surface structure, it is beneficial to improve the regularity of the first circumferential surface 2322b, thereby further improving the avoidance effect of the avoidance part 2322 on the elastic area 242, and reducing the processing and forming difficulty of the first circumferential surface 2322b, so as to reduce the manufacturing difficulty of the cylindrical battery cell 20.

[0309] According to some embodiments of this application, as shown in Figures 6 and 8, the electrode assembly 23 has a central through hole 234. The central through hole 234 extends through both ends of the electrode assembly 23 along the thickness direction X of the wall portion, and the clearance portion 2322 is a portion of the central through hole 234. The central through hole 234 includes a first hole segment 2341 located in the main body portion 231 and a second hole segment 2342 located in the first electrode tab 232. The second hole segment 2342 communicates with the first hole segment 2341, and the second hole segment 2342 is the clearance portion 2322.

[0310] The central through hole 234 is an internal channel for gas flow in the electrode assembly 23 inside the cylindrical battery cell 20. The central through hole 234 passes through both ends of the electrode assembly 23 along the thickness direction X of the wall, that is, the central through hole 234 passes through the first tab 232, the main body 231 and the second tab 233 in sequence along the thickness direction X of the wall.

[0311] The clearance portion 2322 is a portion of the central through hole 234. That is, at least a portion of the central through hole 234 that penetrates the first electrode tab 232 is the clearance portion 2322 of the first electrode tab 232 used to avoid the terminal connection area 243.

[0312] In this embodiment, the electrode assembly 23 is provided with a central through hole 234 that extends through both ends of the electrode assembly 23 along the thickness direction X of the wall. By setting a portion of the central through hole 234 as a clearance portion 2322 for avoiding the terminal connection area 243, the clearance portion 2322 can not only avoid the terminal connection area 243, but also cooperate with the central through hole 234 to vent, which is beneficial to improve the internal venting smoothness of the cylindrical battery cell 20 and can reduce the manufacturing difficulty of the electrode assembly 23.

[0313] In some embodiments, as shown in FIG8, the central through hole 234 includes a first hole segment 2341 and a second hole segment 2342 that are interconnected. At least a portion of the first hole segment 2341 is located within the main body portion 231, and the second hole segment 2342 is located within the first electrode tab 232. The second hole segment 2342 is a clearance portion 2322, and the minimum aperture of the second hole segment 2342 is greater than the aperture of the first hole segment 2341.

[0314] The minimum aperture of the second hole segment 2342 is greater than that of the first hole segment 2341. In other words, the projection of the first hole segment 2341 in the thickness direction X of the wall is located within the second hole segment 2342.

[0315] For example, in Figure 8, the first hole segment 2341 is a hole structure of equal diameter. A portion of the first hole segment 2341 is located within the coating area of ​​the positive and negative electrode sheets of the main body 231 where the active material layer is coated. In an embodiment where the first electrode tab 232 is a positive electrode tab and a positive transition region is provided in the positive electrode blank area of ​​the positive electrode sheet, a portion of the first hole segment 2341 is also located within the blank area of ​​the positive electrode sheet of the main body 231 where the active material layer is not coated. In an embodiment where the first electrode tab 232 is a negative electrode tab and a negative transition region is provided in the negative electrode blank area of ​​the negative electrode sheet, a portion of the first hole segment 2341 is also located within the blank area of ​​the negative electrode sheet of the main body 231 where the active material layer is not coated. It should be noted that in the main body In an embodiment where the separator of body 231 extends along the thickness direction X of the wall to the first tab 232, the first hole segment 2341 can also be a structure partially located within the first tab 232. Correspondingly, the second hole segment 2342 is a structure where the overall hole diameter is larger than the hole diameter of the first hole segment 2341. Similarly, the second hole segment 2342 can also be a hole structure of equal diameter or a stepped hole structure. For example, referring to FIG8, in an embodiment where an inclined first circumferential surface 2322b is formed on the hole wall surface of the second hole segment 2342, the second hole segment 2342 is a structure comprising two interconnected hole segments, one hole segment being a hole structure of equal diameter and the other hole segment being a hole structure with a gradually increasing hole diameter.

[0316] In this embodiment, by setting the second hole segment 2342 located within the first electrode tab 232 as a clearance portion 2322, and setting the hole diameter of the second hole segment 2342 to be larger than that of the first hole segment 2341, the effect of the second hole segment 2342 as a clearance portion 2322 in avoiding the terminal connection area 243 is improved, while also alleviating the phenomenon that the first hole segment 2341 located within the main body 231 occupies too much space, thereby helping to improve the energy density of the electrode assembly 23.

[0317] It should be noted that the structure of the electrode assembly 23 is not limited to this. In some embodiments, the electrode assembly 23 can also have other structures. For example, the diameter of the first hole segment 2341 is equal to the diameter of the second hole segment 2342. That is, the first hole segment 2341 and the second hole segment 2342 are both hole structures with the same diameter. In other words, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projection of the hole wall surface of the first hole segment 2341 and the orthographic projection of the hole wall surface of the second hole segment 2342 completely overlap.

[0318] In this embodiment, by setting the diameter of the first hole segment 2341 and the diameter of the second hole segment 2342 of the central through hole 234 to be equal, the processing difficulty of the central through hole 234 can be reduced while the second hole segment 2342 acts as a clearance part 2322 to avoid the terminal connection area 243, thereby reducing the manufacturing difficulty of the electrode assembly 23.

[0319] According to some embodiments of this application, referring to FIG7, the terminal connection area 243 is connected to the current collection body area 241 only through a single elastic area 242. That is, there is only one elastic area 242 connecting a terminal connection area 243 and a current collection body area 241.

[0320] In this embodiment, by setting the terminal connection area 243 to be connected to the current collection body area 241 through only one elastic area 242, the elastic area 242 can be better deformed when the terminal connection area 243 and the current collection body area 241 move closer or further away from each other along the thickness direction X of the wall, which is beneficial to further expand the range of movement of the terminal connection area 243 relative to the current collection body area 241 in the thickness direction X of the wall.

[0321] Of course, the structure of the first current collector 24 is not limited to this. In some embodiments, the first current collector 24 can also have other structures. For example, the first current collector 24 includes multiple elastic regions 242, and the terminal connection region 243 is connected to the current collector body region 241 through the multiple elastic regions 242. That is, multiple elastic regions 242 are connected between a terminal connection region 243 and a current collector body region 241. It should be noted that in embodiments where the current collector body region 241 is an annular structure surrounding the terminal connection region 243, the multiple elastic regions 242 can also be a structure that is circumferentially spaced and asymmetrically arranged along the current collector body region 241.

[0322] In this embodiment, by setting the terminal connection area 243 to be interconnected with the current collection body area 241 through multiple elastic areas 242, it is beneficial to improve the connection reliability between the terminal connection area 243 and the current collection body area 241, and can further increase the flow area between the terminal connection area 243 and the current collection body area 241.

[0323] According to some embodiments of this application, please continue to refer to Figure 7, the current collector body area 241, the elastic area 242, and the terminal connection area 243 are integrally formed. That is, the current collector body area 241, the elastic area 242, and the terminal connection area 243 of the first current collector component 24 are structures made by an integral forming process, such as stamping, casting, or milling.

[0324] Of course, the current collection main body area 241, elastic area 242 and terminal connection area 243 of the first current collection component 24 can also be a separate structure. For example, the current collection main body area 241 is welded to the elastic area 242, and the elastic area 242 is welded to the terminal connection area 243.

[0325] In this embodiment, by setting the current collection body area 241, elastic area 242 and terminal connection area 243 of the first current collection component 24 as an integral structure, on the one hand, the connection difficulty between the elastic area 242 and the current collection body area 241 and the terminal connection area 243 can be reduced, thereby reducing the processing difficulty of the first current collection component 24. On the other hand, the connection reliability and stability between the current collection body area 241, elastic area 242 and terminal connection area 243 can be improved, which is conducive to alleviating the phenomenon of breakage between the current collection body area 241 and the elastic area 242 and between the elastic area 242 and the terminal connection area 243 during use, thereby reducing the risk of connection failure between the electrode terminal 22 and the electrode assembly 23.

[0326] According to some embodiments of this application, the Vickers hardness of the elastic region 242 is greater than or equal to 10 and less than or equal to 70.

[0327] For example, the Vickers hardness of the elastic region 242 can be 10, 11, 12, 13, 14, 15, 16, 18, 20, 22, 25, 28, 30, 32, 35, 38, 40, 42, 45, 48, 50, 52, 55, 58, 60, 61, 62, 63, 64, 65, 67, 68, 69 or 70, etc.

[0328] In this embodiment, by setting the Vickers hardness of the elastic region 242 to 10 to 70, the elastic region 242 has good structural strength and good deformation capacity. This allows the elastic region 242 to play a good buffering role between the current collector body region 241 and the terminal connection region 243, while also enabling the elastic region 242 to better support the terminal connection region 243. This helps to alleviate the phenomenon of poor assembly caused by the terminal connection region 243 failing to make effective contact with the electrode terminal 22.

[0329] According to some embodiments of this application, the material of the elastic region 242 includes aluminum.

[0330] For example, the entire material of the first current collector 24 is aluminum, and the material of the first tab 232 is aluminum, so that the tab connection area 244 of the first current collector 24 and the first tab 232 are welded together with the same material, which helps to reduce the welding difficulty.

[0331] In this embodiment, the use of aluminum material for the elastic region 242 enables the elastic region 242 to have good flow conduction ability while also enabling the elastic region 242 to have good deformation ability.

[0332] According to some embodiments of this application, referring to FIG7, and further referring to FIGS. 9 and 10, FIG9 is a cross-sectional view of the elastic region 242 of the first current collector 24 provided in some embodiments of this application perpendicular to its extension direction, and FIG10 is a front view of the first current collector 24 provided in some embodiments of this application in the thickness direction X of the wall portion. The elastic region 242 is connected to the current collector body region 241 and the terminal connection region 243 at opposite ends in its extension direction, and the area S of the cross-section of the elastic region 242 perpendicular to its extension direction satisfies 0.2 mm. 2 ≤S≤8mm 2 .

[0333] The area S of the cross-section of the elastic region 242 perpendicular to its extension direction can be 2 mm². 2 2.1mm 2 2.3mm 2 2.5mm 2 2.8mm 2 3mm 2 3.2mm 2 3.5mm 2 3.8mm 2 4mm 2 4.2mm 2 4.5mm 2 4.8mm 2 5mm 2 5.2mm 2 5.5mm 2 5.8mm 2 6mm 2 6.2mm 2 6.5mm 2 6.8mm 2 7mm 2 7.2mm 2 7.5mm 2 7.8mm 2 7.9mm 2 Or 8mm 2 wait.

[0334] In this embodiment, the area of ​​the cross-section of the elastic region 242 perpendicular to its extending direction is 0.2 mm. 2 up to 8mm 2 On the one hand, the area of ​​the cross-section of the elastic zone 242 perpendicular to its extension direction is set to be greater than or equal to 0.2 mm. 2This increases the flow area of ​​the elastic zone 242, thereby improving the flow capacity of the first current collector 24. On the other hand, the cross-sectional area of ​​the elastic zone 242 perpendicular to its extension direction is set to be less than or equal to 8 mm². 2 This allows the elastic zone 242 to deform better between the current collector area 241 and the terminal connection area 243, which is beneficial to improving the deformation capability of the elastic zone 242.

[0335] In some embodiments, as shown in Figures 9 and 10, the cross-section is rectangular, with a length and width of L and W respectively, satisfying 1mm≤L≤10mm and 0.2mm≤W≤0.8mm.

[0336] Wherein, the width direction of the cross-section of the elastic region 242 perpendicular to its extension direction is the thickness direction X of the wall. For example, the orthographic projection of the elastic region 242 in the projection plane perpendicular to the thickness direction X of the wall is a structure extending radially along the cylindrical battery cell 20. Correspondingly, the length direction of the cross-section of the elastic region 242 perpendicular to its extension direction is perpendicular to the radial direction of the cylindrical battery cell 20.

[0337] For example, the length L of the cross section of the elastic region 242 perpendicular to its extension direction can be 1mm, 1.1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm or 10mm, etc.

[0338] For example, the width W of the cross section of the elastic region 242 perpendicular to its extension direction can be 0.2mm, 0.21mm, 0.22mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.78mm, 0.79mm, or 0.8mm, etc.

[0339] In this embodiment, by setting the length of the cross-section of the elastic region 242 perpendicular to its extension direction to 1mm to 10mm, and setting the width of the cross-section of the elastic region 242 perpendicular to its extension direction to 0.2mm to 0.8mm, the elastic region 242 is made into a flat structure. The elastic region 242 with this structure can not only meet the flow requirements of the elastic region 242, but also improve the deformation capacity of the elastic region 242, and reduce the processing difficulty and space occupied by the elastic region 242.

[0340] According to some embodiments of this application, as shown in Figures 7 and 10, the current collection body area 241 is an annular structure surrounding the terminal connection area 243. The terminal connection area 243 and the current collection body area 241 are spaced apart, and the elastic area 242 is connected to the outer peripheral surface of the terminal connection area 243 and the inner peripheral surface of the current collection body area 241 at opposite ends in its extension direction.

[0341] The elastic region 242 is connected to the outer peripheral surface of the terminal connection region 243 and the inner peripheral surface of the current collector region 241 at opposite ends in its extension direction. In other words, the elastic region 242 is a structure that connects the terminal connection region 243 and the current collector region 241 in the radial direction of the cylindrical battery cell 20.

[0342] In this embodiment, by setting the current collecting body area 241 as an annular structure surrounding the outer side of the terminal connection area 243, and the elastic area 242 having its two opposite ends connected to the outer peripheral surface of the terminal connection area 243 and the inner peripheral surface of the current collecting body area 241 respectively in its extending direction, the elastic area 242 is a structure connecting the terminal connection area 243 and the current collecting body area 241. The first current collecting member 24 with this structure is convenient for the elastic area 242 to deform and for the terminal connection area 243 to be assembled and connected with the electrode terminal 22, which helps to reduce the connection difficulty between the terminal connection area 243 and the electrode terminal 22. On the other hand, it can optimize the structural layout of the current collecting body area 241, the elastic area 242 and the terminal connection area 243, so that the current collecting body area 241 of the first current collecting member 24 can be assembled between the wall portion 211 and the first electrode tab 232, which helps to improve the structural stability of the current collecting body area 241 of the first current collecting member 24 disposed between the wall portion 211 and the first electrode tab 232.

[0343] In some embodiments, referring to FIG10, the orthographic projection of the elastic region 242 extends radially along the cylindrical battery cell 20 in a projection plane perpendicular to the thickness direction X of the wall portion.

[0344] In this embodiment, by setting the orthographic projection of the elastic region 242 in the projection plane perpendicular to the thickness direction X of the wall portion as a structure extending radially along the cylindrical battery cell 20, the elastic region 242 is a strip-shaped structure arranged radially along the cylindrical battery cell 20 between the current collector body region 241 and the terminal connection region 243. This facilitates the deformation of the elastic region 242 when the current collector body region 241 and the terminal connection region 243 move closer or further apart along the thickness direction X of the wall portion, which helps to improve the buffering effect of the elastic region 242 between the current collector body region 241 and the terminal connection region 243, and can improve the effect of the elastic region 242 in absorbing the assembly error between the terminal connection region 243 and the electrode terminal 22. On the other hand, it can improve the regularity of the shape of the first current collector component 24, which helps to reduce the processing difficulty of the first current collector component 24.

[0345] According to some embodiments of this application, as shown in FIG10, the elastic region 242 is connected to the current collection body region 241 and the terminal connection region 243 at opposite ends in its extension direction, and the dimension of the elastic region 242 in its extension direction is D, and the radius of the current collection body region 241 is R, satisfying 0.4R≤D≤0.95R.

[0346] Wherein, the dimension D of the elastic zone 242 in its extension direction is the length of the elastic zone 242 in its extension direction, and the radius R of the main flow collection zone 241 is the radius of the circle containing the outer edge of the orthographic projection of the main flow collection zone 241 in the projection plane perpendicular to the thickness direction X of the wall.

[0347] For example, the dimension D of the elastic region 242 in its extension direction can be 0.4 times, 0.42 times, 0.45 times, 0.5 times, 0.55 times, 0.6 times, 0.65 times, 0.7 times, 0.75 times, 0.8 times, 0.85 times, 0.9 times, or 0.95 times the radius R of the main flow collection region 241.

[0348] In this embodiment, by setting the dimension D of the elastic region 242 in its extension direction to be greater than or equal to 0.4 times the radius R of the current collector 241, the elastic region 242 has sufficient length to deform. This is beneficial to improving the ability of the elastic region 242 to deform when the current collector 241 and the terminal connection area 243 move closer or further apart along the thickness direction X of the wall. In addition, by setting the dimension D of the elastic region 242 in its extension direction to be less than or equal to 0.95 times the radius R of the current collector 241, the phenomenon that the area of ​​the terminal connection area 243 is too small due to the excessive space occupied by the elastic region 242 is alleviated. This is beneficial to increasing the connection area between the terminal connection area 243 and the electrode terminal 22, thereby improving the current flow area and connection reliability between the terminal connection area 243 and the electrode terminal 22.

[0349] In some embodiments, please continue to refer to Figure 10, 8mm≤D≤25mm.

[0350] For example, the dimension D of the elastic region 242 in its extension direction can be 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm or 25mm, etc.

[0351] In this embodiment, by setting the dimension of the elastic region 242 in its extension direction to be greater than or equal to 8 mm, the elastic region 242 has sufficient length to deform, which is beneficial to further improve the ability of the elastic region 242 to deform when the current collector area 241 and the terminal connection area 243 move closer or further apart along the thickness direction X of the wall. In addition, by setting the dimension of the elastic region 242 in its extension direction to be less than or equal to 25 mm, the phenomenon of insufficient strength of the elastic region 242 caused by excessive length is alleviated, so that the elastic region 242 can better support the terminal connection area 243, thereby effectively alleviating the phenomenon of poor assembly caused by the terminal connection area 243 failing to make effective contact with the electrode terminal 22.

[0352] According to some embodiments of this application, referring to Figures 7 and 10, the first current collection member 24 may further include a base region 245, and the elastic region 242 is connected to the current collection body region 241 through the base region 245. In the projection plane perpendicular to the thickness direction X of the wall, the width of the orthographic projection of the base region 245 in the circumferential direction of the current collection body region 241 is greater than the width of the orthographic projection of the elastic region 242 in the circumferential direction of the current collection body region 241.

[0353] It should be noted that if the base region 245 has a uniform width, then the width of the base region 245 in the circumferential direction of the main flow collection region 241 is greater than the width of the elastic region 242 in the circumferential direction of the main flow collection region 241; if the base region 245 has a gradually changing width, then the minimum width of the base region 245 in the circumferential direction of the main flow collection region 241 is greater than or equal to the width of the elastic region 242 in the circumferential direction of the main flow collection region 241. For example, referring to Figures 7 and 10, if the width of the base region 245 in the circumferential direction of the main flow collection region 241 gradually increases from one end connected to the elastic region 242 to one end connected to the main flow collection region 241, then the width of the base region 245 at the end connected to the elastic region 242 is the minimum width of the base region 245 in the circumferential direction of the main flow collection region 241.

[0354] In this embodiment, the first current collecting component 24 is further provided with a base region 245 connecting the elastic region 242 and the current collecting main body region 241. The width of the base region 245 in the circumferential direction of the current collecting main body region 241 is greater than the width of the elastic region 242 in the circumferential direction of the current collecting main body region 241. This makes the elastic region 242 a structure that is connected to the current collecting main body region 241 through the base region 245 with a larger width. This helps to reduce the connection difficulty between the elastic region 242 and the annular current collecting main body region 241, and can improve the connection stability of the elastic region 242 connected to the inner circumferential surface of the current collecting main body region 241.

[0355] In some embodiments, as shown in Figures 7 and 10, the base region 245 has a first end 2451 and a second end 2452 opposite to each other. The first end 2451 is connected to the elastic region 242, and the second end 2452 is connected to the collection body region 241. In a projection plane perpendicular to the thickness direction X of the wall, the width of the orthographic projection of the base region 245 onto the circumferential direction of the collection body region 241 gradually increases from the first end 2451 to the second end 2452. That is, the width of the end of the base region 245 connected to the elastic region 242 is the minimum width of the base region 245 in the circumferential direction of the collection body region 241, while the width of the end of the base region 245 connected to the inner circumferential surface of the collection body region 241 is the maximum width of the base region 245 in the circumferential direction of the collection body region 241.

[0356] In this embodiment, by configuring the base region 245 such that the width of the main body region 241 gradually increases from the first end 2451 connected to the elastic region 242 to the second end 2452 connected to the main body region 241 in the circumferential direction, it is possible to reduce the width of the end where the base region 245 is connected to the elastic region 242. This helps to reduce the width difference at the connection position between the base region 245 and the elastic region 242, thereby reducing the difficulty of connecting and molding the base region 245 and the elastic region 242, and enabling the base region 245 and the elastic region 242 to achieve the desired connection. The transition at the connection position of the elastic zone 242 is smoother. On the other hand, the increased width of the second end 2452 connecting the base zone 245 and the main collection zone 241 can expand the angle at the connection position between the inner circumferential surfaces of the base zone 245 and the main collection zone 241, thereby alleviating the stress concentration at the connection position between the base zone 245 and the main collection zone 241. This helps to reduce the risk of damage or cracking at the connection position between the base zone 245 and the main collection zone 241, thereby improving the reliability and service life of the first collection component 24.

[0357] According to some embodiments of this application, as shown in Figures 7 and 10, the first current collector 24 may further include a tab connection area 244, which is connected to the inner circumferential surface of the current collector body area 241 and is connected to the first tab 232 to electrically connect the current collector body area 241 and the first tab 232.

[0358] The tab connection area 244 is connected to the inner circumferential surface of the current collection body area 241, that is, the tab connection area 244 is located on the inner circumferential side of the current collection body area 241.

[0359] It should be noted that in other embodiments, the first current collector 24 may not have a tab connection area 244, and correspondingly, the current collector body area 241 is directly connected to the first tab 232.

[0360] Optionally, the tab connection area 244 and the current collector body area 241 are integrally formed, that is, the tab connection area 244 and the current collector body area 241 are an integral structure made by an integral forming process.

[0361] In this embodiment, the first current collector 24 is further provided with a tab connection area 244 for interconnecting with the first tab 232. The tab connection area 244 is connected to the inner circumferential surface of the current collector body area 241. On the one hand, it facilitates the connection between the current collector body area 241 and the first tab 232 through the tab connection area 244, which helps to reduce the connection difficulty between the first current collector 24 and the first tab 232 and increases the connection area between the first current collector 24 and the first tab 232. On the other hand, it can optimize the structural layout between the tab connection area 244 and the current collector body area 241, so as to assemble the current collector body area 241 of the first current collector 24 between the wall portion 211 and the first tab 232, which helps to improve the structural stability of the current collector body area 241 of the first current collector 24 between the wall portion 211 and the first tab 232.

[0362] In some embodiments, as shown in FIG10, the tab connection region 244 extends radially along the cylindrical battery cell 20.

[0363] In this embodiment, by setting the tab connection area 244 to extend radially along the cylindrical battery cell 20, the connection area between the tab connection area 244 and the first tab 232 can be increased, thereby improving the connection stability between the tab connection area 244 and the first tab 232. Furthermore, the first tab 232 can be connected to the tab connection area 244 at multiple positions radially along the cylindrical battery cell 20, ensuring that all multiple turns of the first tab 232 of the cylindrical electrode assembly 23 can be connected to the tab connection area 244. This is beneficial for increasing the current flow area between the first tab 232 and the tab connection area 244, and also improves the current flow balance between the electrode assembly 23 and the tab connection area 244, thereby reducing the risk of localized lithium plating in the electrode assembly 23 during use.

[0364] According to some embodiments of this application, referring to Figures 7 and 10, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projections of the terminal connection area 243 and the elastic area 242 do not overlap with the orthographic projection of the tab connection area 244. That is, the projections of the terminal connection area 243, the elastic area 242, and the tab connection area 244 in the thickness direction X of the wall do not overlap with each other.

[0365] In this embodiment, by setting the projections of the terminal connection area 243 and the elastic area 242 on the thickness direction X of the wall to be non-overlapping with the projection of the tab connection area 244 on the thickness direction X of the wall, the obstruction and interference of the tab connection area 244 on the terminal connection area 243 and the elastic area 242 can be reduced when the terminal connection area 243 is close to or far from the current collector body area 241 on the thickness direction X of the wall. This is beneficial to expanding the movement range of the terminal connection area 243 relative to the current collector body area 241 on the thickness direction X of the wall, and can improve the deformation degree of the elastic area 242 on the thickness direction X of the wall. This can further improve the effect of the elastic area 242 in absorbing the assembly error between the electrode terminal 22 and the terminal connection area 243, so as to further improve the assembly quality between the electrode terminal 22 and the terminal connection area 243, and can further improve the buffering effect of the elastic area 242 between the current collector body area and the terminal connection area 243, so as to further reduce the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23.

[0366] In some embodiments, please continue to refer to Figures 7 and 10, the first current collector 24 may include a plurality of tab connection regions 244, which are arranged at circumferential intervals along the current collector body region 241.

[0367] For example, the first current collector 24 is provided with four tab connection areas 244, all of which are connected to the inner circumferential surface of the current collector body area 241. The four tab connection areas 244 are spaced apart and evenly arranged along the circumference of the current collector body area 241, and each tab connection area 244 is a structure that extends radially along the cylindrical battery cell 20. Of course, in other embodiments, the number of tab connection areas 244 connected on the current collector body area 241 can also be two, three, five, or six, etc.

[0368] In this embodiment, by connecting multiple tab connection areas 244 on the current collector main body region 241, and the multiple tab connection areas 244 are arranged at intervals along the circumference of the current collector main body region 241, on the one hand, the connection area between the first current collector component 24 and the first tab 232 can be further increased, thereby increasing the flow area between the first current collector component 24 and the first tab 232. On the other hand, it can be realized that the first tab 232 is connected to multiple positions in the circumference of the main body region by tab connection areas 244, which is beneficial to improving the flow balance between the electrode assembly 23 and the first current collector component 24, thereby reducing the risk of local lithium plating in the electrode assembly 23 during use.

[0369] According to some embodiments of this application, as shown in Figures 6 and 7, the terminal connection area 243 is welded to one end of the electrode terminal 22 near the main body 231. That is, the terminal connection area 243 and the electrode terminal 22 are stacked and welded to each other along the thickness direction X of the wall. Correspondingly, the first surface 2431 of the terminal connection area 243 and the connection surface 223 of the electrode terminal 22 abut against each other and are welded together.

[0370] For example, the terminal connection area 243 can be welded to the electrode terminal 22 in various ways, such as laser welding or ultrasonic welding.

[0371] In this embodiment, by configuring the terminal connection area 243 to be welded to the end of the electrode terminal 22 in the thickness direction X of the wall near the main body 231, the terminal connection area 243 is a structure welded to the end face of the electrode terminal 22 in the thickness direction X of the wall near the main body 231. On the one hand, this can improve the connection stability and overcurrent stability between the terminal connection area 243 and the electrode terminal 22. On the other hand, under the action of the elastic area 242, it can absorb the assembly error between the electrode terminal 22 and the terminal connection area 243, thereby alleviating the welding gap between the terminal connection area 243 and the electrode terminal 22. This helps to reduce the risk of poor soldering between the terminal connection area 243 and the electrode terminal 22, thereby improving the welding quality between the terminal connection area 243 and the electrode terminal 22.

[0372] In some embodiments, as shown in Figures 6, 7, and 8, the electrode assembly 23 has a central through-hole 234 that extends through both ends of the electrode assembly 23 along the thickness direction X of the wall. A terminal connection area 243 is welded to the electrode terminal 22 to form a connection portion 28, the projection of which lies within the central through-hole 234 along the thickness direction X of the wall.

[0373] The connection portion 28 formed by welding the terminal connection area 243 and the electrode terminal 22 is a solder mark formed by welding the terminal connection area 243 and the electrode terminal 22 together.

[0374] Along the thickness direction X of the wall, the projection of the connecting part 28 is located inside the central through hole 234. That is, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projection of the connecting part 28 is located inside the orthographic projection of the hole wall surface of the central through hole 234.

[0375] In this embodiment, by setting the connection portion 28 formed by welding the terminal connection area 243 and the electrode terminal 22 together, the projection of the connection portion 28 in the thickness direction X of the wall portion is located in the central through hole 234. This allows the welding assembly to be performed from the side of the terminal connection area 243 away from the electrode terminal 22 through the central through hole 234 when welding the terminal connection area 243 and the electrode terminal 22 together. This helps to reduce the power required for welding the terminal connection area 243 and the electrode terminal 22 together, thereby reducing the welding difficulty between the terminal connection area 243 and the electrode terminal 22, and improving the welding quality between the terminal connection area 243 and the electrode terminal 22, thereby improving the connection reliability between the terminal connection area 243 and the electrode terminal 22.

[0376] According to some embodiments of this application, referring to FIG6 and further referring to FIG11, FIG11 is a cross-sectional view of an electrode terminal 22 provided in some embodiments of this application. The electrode terminal 22 may include a terminal body 221 and a protrusion 222. The terminal body 221 is connected to the wall portion 211, and the protrusion 222 is connected to the terminal body 221. Along the thickness direction X of the wall portion, the protrusion 222 protrudes from the end of the terminal body 221 facing the main body portion 231, and the end of the protrusion 222 near the main body portion 231 is connected to the terminal connection area 243.

[0377] The terminal body 221 is insulatedly mounted on the wall portion 211, and the terminal body 221 passes through the mounting hole 2111 of the wall portion 211 along the thickness direction X. A sealing member 25 is provided between the terminal body 221 and the wall portion 211. The sealing member 25 is configured to seal the gap between the terminal body 221 and the hole wall surface of the mounting hole 2111. The sealing member 25 is made of insulating material, so that the sealing member 25 can also insulate and isolate the terminal body 221 and the wall portion 211, so that the terminal body 221 is insulatedly mounted on the wall portion 211, that is, no electrical connection is formed between the terminal body 221 and the wall portion 211.

[0378] The protrusion 222 protrudes from one end of the terminal body 221 facing the main body 231, and the end of the protrusion 222 near the main body 231 is connected to the terminal connection area 243. In other words, the protrusion 222 is a convex structure protruding from the end of the terminal body 221 facing the terminal connection area 243 in the thickness direction X of the wall portion, and the protrusion 222 is connected to the terminal connection area 243. For example, the protrusion 222 is welded to the terminal connection area 243 to form a connection portion 28. Correspondingly, in an embodiment where the electrode terminal 22 has a connection surface 223 that connects to the terminal connection area 243, the end face of the protrusion 222 facing the terminal connection area 243 in the thickness direction X of the wall portion is the connection surface 223 of the electrode terminal 22.

[0379] In this embodiment, the electrode terminal 22 includes a terminal body 221 connected to the wall portion 211 and a protrusion 222 protruding from one end of the terminal body 221 near the main body portion 231. The protrusion 222 is connected to the terminal connection area 243 of the first current collector 24. The electrode terminal 22 with this structure can reduce the connection difficulty between the electrode terminal 22 and the terminal connection area 243 and reduce the interference between the terminal connection area 243 and the terminal body 221. On the other hand, it is convenient for the electrode terminal 22 to press down on the terminal connection area 243 along the thickness direction X of the wall portion through the protrusion 222, which is beneficial to absorb the assembly error between the electrode terminal 22 and the terminal connection area 243, thereby effectively improving the assembly quality between the terminal connection area 243 and the electrode terminal 22.

[0380] In some embodiments, as shown in Figures 6 and 11, the terminal body 221 has a first limiting portion 2211 and a second limiting portion 2212. The first limiting portion 2211 and the second limiting portion 2212 are spaced apart along the thickness direction X of the wall portion, and at least a portion of the wall portion 211 is located between the first limiting portion 2211 and the second limiting portion 2212.

[0381] The first limiting part 2211 is located on the side of the wall portion 211 facing the electrode assembly 23 in the thickness direction X of the wall portion, and the second limiting part 2212 is located on the side of the wall portion 211 away from the electrode assembly 23 in the thickness direction X of the wall portion, so that the first limiting part 2211 and the second limiting part 2212 can cooperate to clamp at least a portion of the wall portion 211, so as to fasten the terminal body 221 to the wall portion 211.

[0382] Optionally, referring to Figures 6 and 11, and further referring to Figure 12, which is a cross-sectional view of a seal 25 provided in some embodiments of this application, the seal 25 includes a first sealing portion 251, a second sealing portion 252, and a third sealing portion 253 connected in sequence. The first sealing portion 251 is located between the first limiting portion 2211 and the wall portion 211, the second sealing portion 252 is located between the terminal body 221 and the wall surface of the mounting hole 2111, and the third sealing portion 253 is located between the second limiting portion 2212 and the wall portion 211. This facilitates improving the sealing effect of the seal 25 on the wall portion 211 and the electrode terminal 22, and also improves the insulating effect of the seal 25 on the wall portion 211 and the electrode terminal 22. It should be noted that, as shown in Figures 6 and 12, the first sealing portion 251 of the seal 25 extends radially beyond the outer peripheral surface of the first limiting portion 2211 of the cylindrical battery cell 20.

[0383] In this embodiment, by providing a first limiting portion 2211 and a second limiting portion 2212 arranged at intervals along the thickness direction X of the wall portion on the terminal body 221, and at least a portion of the wall portion 211 being located between the first limiting portion 2211 and the second limiting portion 2212, the first limiting portion 2211 and the second limiting portion 2212 of the terminal body 221 are respectively located on both sides of the wall portion 211 in the thickness direction X of the wall portion, so that the first limiting portion 2211 and the second limiting portion 2212 can cooperate to clamp the wall portion 211, thereby realizing the installation of the terminal body 221 of the electrode terminal 22 on the wall portion 211. The structure is simple and easy to implement and assemble.

[0384] In some embodiments, referring to Figures 4 and 6, the cylindrical battery cell 20 may further include a first insulating member 27. The first insulating member 27 includes a first insulating portion 271, which is disposed between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion. The first insulating portion 271 is provided with a through hole 2711, which penetrates both sides of the first insulating portion 271 in the thickness direction X of the wall portion. Along the thickness direction X of the wall portion, the electrode terminal 22 extends into the through hole 2711, and the protrusion 222 protrudes from the surface of the first insulating portion 271 facing the first current collector 24.

[0385] The terminal body 221 of the electrode terminal 22 extends along the thickness direction X of the wall into the through hole 2711 of the first insulating part 271. The protrusion 222 protrudes from the surface of the first insulating part 271 facing the first current collector 24. That is, the protrusion 222 is a structure in which the through hole 2711 extends away from the wall 211 in the thickness direction X of the wall, so that the surface of the protrusion 222 facing the terminal connection area 243 in the thickness direction X of the wall is farther away from the wall 211 than the surface of the first insulating part 271 facing the first current collector 24.

[0386] In this embodiment, the cylindrical battery cell 20 is further provided with a first insulating member 27. The first insulating member 27 includes a first insulating portion 271 disposed between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion. By setting the protrusion 222 to protrude from the surface of the first insulating portion 271 facing the first current collector 24 in the thickness direction X of the wall portion, the obstruction and interference of the first insulating portion 271 on the protrusion 222 can be reduced, so that the protrusion 222 can be connected to the terminal connection area 243, which helps to reduce the connection difficulty between the protrusion 222 and the terminal connection area 243.

[0387] According to some embodiments of this application, referring to Figures 4 and 6, and further referring to Figure 13, Figure 13 is a cross-sectional view of the first insulating member 27 of the cylindrical battery cell 20 provided in some embodiments of this application. The cylindrical battery cell 20 may further include the first insulating member 27, which includes a first insulating portion 271. The first insulating portion 271 is disposed between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion to insulate and isolate the wall portion 211 and the first current collector 24. The first insulating portion 271 is provided with a through hole 2711, which penetrates both sides of the first insulating portion 271 in the thickness direction X of the wall portion. Along the thickness direction X of the wall portion, the electrode terminal 22 extends into the through hole 2711.

[0388] The first insulating portion 271 is the portion of the first insulating member 27 located between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion.

[0389] The first insulating part 271 is provided with a through hole 2711. The through hole 2711 is a structure that penetrates the surface of both sides of the first insulating part 271 along the thickness direction X of the wall. A portion of the electrode terminal 22 extends into the through hole 2711 so that the electrode terminal 22 can be connected to the terminal connection area 243.

[0390] For example, the material of the first insulating member 27 can be various, such as rubber, plastic or silicone.

[0391] In this embodiment, the cylindrical battery cell 20 is further provided with a first insulating member 27, and the first insulating member 27 includes a first insulating portion 271 disposed in the thickness direction X of the wall portion between the wall portion 211 and the first current collector 24, so that the first insulating portion 271 of the first insulating member 27 can insulate and separate the wall portion 211 and the first current collector 24, thereby reducing the risk of short circuit between the wall portion 211 and the first current collector 24 during use. In this embodiment, by providing a through hole 2711 extending in the thickness direction X of the wall portion on the first insulating portion 271, and the electrode terminal 22 extending in the thickness direction X of the wall portion into the through hole 2711, the electrode terminal 22 can be connected to the terminal connection area 243 of the first current collector 24 located on the side of the first insulating portion 271 opposite to the wall portion 211, which helps to reduce the assembly difficulty between the electrode terminal 22 and the first current collector 24.

[0392] According to some embodiments of this application, referring to Figures 6, 7, and 13, the electrode terminals 22 and the terminal connection area 243 are arranged along the thickness direction X of the wall portion. Along the thickness direction X, the terminal connection area 243 has a first surface 2431 facing away from the main body portion 231. The electrode terminals 22 have a connecting surface 223 facing the main body portion 231, and the connecting surface 223 and the first surface 2431 are welded together. Along the thickness direction X of the wall portion, the first insulating portion 271 has a sixth surface 2712 facing the first tab 232, and the sixth surface 2712 is further away from the main body portion 231 than the connecting surface 223. In other words, the end of the electrode terminal 22 near the main body portion 231 in the thickness direction X of the wall portion has a structure that protrudes from the side of the first insulating portion 271 facing the main body portion 231.

[0393] In this embodiment, by setting the sixth surface 2712 of the first insulating portion 271 facing the first tab 232 to be closer to the main body 231 in the thickness direction X of the wall portion than the connecting surface 223 where the electrode terminal 22 and the terminal connection area 243 are connected, the end of the electrode terminal 22 near the main body 231 in the thickness direction X of the wall portion is a structure that protrudes from the side of the first insulating portion 271 facing the first tab 232. This reduces the obstruction and interference of the first insulating portion 271 on the electrode terminal 22, making it easier for the connecting surface 223 of the electrode terminal 22 to be welded to the first surface 2431 of the terminal connection area 243. It also facilitates the electrode terminal 22 to press against the terminal connection area 243 along the thickness direction X of the wall portion, which helps to improve the contact effect between the first surface 2431 and the connecting surface 223. This effectively improves the welding quality between the first surface 2431 and the connecting surface 223, thereby reducing phenomena such as incomplete soldering between the terminal connection area 243 and the electrode terminal 22.

[0394] Of course, the structure of the cylindrical battery cell 20 is not limited to this. In some embodiments, the cylindrical battery cell 20 can also have other structures. For example, the electrode terminals 22 and the terminal connection area 243 are arranged along the thickness direction X of the wall portion. Along the thickness direction X of the wall portion, the terminal connection area 243 has a first surface 2431 facing away from the main body portion 231, and the electrode terminals 22 have a connection surface 223 facing the main body portion 231. The connection surface 223 and the first surface 2431 are welded together. Along the thickness direction X of the wall portion, the first insulating portion 271 has a sixth surface 2712 facing the first tab 232, and the sixth surface 2712 is closer to the main body portion 231 than the connection surface 223. In other words, in the implementation where the terminal connection area 243 is raised in the thickness direction X of the wall relative to the current collection body area 241 towards the wall 211, the end of the electrode terminal 22 near the body 231 in the thickness direction X of the wall does not extend beyond the side of the first insulating portion 271 facing the first tab 232, so that the end of the electrode terminal 22 near the body 231 in the thickness direction X of the wall does not extend out of the through hole 2711.

[0395] In this embodiment, the sixth surface 2712 of the first insulating portion 271 facing the first tab 232 is configured to be closer to the main body 231 in the thickness direction X of the wall portion than the connecting surface 223 of the electrode terminal 22. This results in the end of the electrode terminal 22 in the thickness direction X of the wall portion near the main body 231 being located inside the through hole 2711 and not extending out of the side of the first insulating portion 271 facing the first tab 232. This reduces the phenomenon that the electrode terminal 22 occupies the space on the side of the first insulating portion 271 facing the first tab 232, and also reduces the interference between the electrode terminal 22 and other components.

[0396] In this embodiment, at least a portion of the terminal connection area 243 is accommodated within the through hole 2711 along the thickness direction X of the wall portion, that is, the terminal connection area 243 may be a structure in which it is inserted into the through hole 2711 of the first insulating portion 271 along the thickness direction X of the wall portion.

[0397] In this embodiment, by configuring at least a portion of the terminal connection area 243 to be accommodated within the through hole 2711 in the thickness direction X of the wall, the terminal connection area 243 can share a portion of the space with the first insulating portion 271 in the thickness direction X of the wall, which is beneficial to improving the internal space utilization of the cylindrical battery cell 20.

[0398] In some embodiments, as shown in Figures 6, 11, 12, and 13, the wall portion 211 is provided with a mounting hole 2111, which penetrates the wall portion 211 along the thickness direction X. The electrode terminal 22 passes through the mounting hole 2111. The cylindrical battery cell 20 also includes a sealing member 25, which is disposed between the electrode terminal 22 and the wall portion 211 to seal the gap between the electrode terminal 22 and the hole wall surface of the mounting hole 2111. The electrode terminal includes a first limiting portion located on the side of the wall portion facing the electrode assembly. The sealing member is made of insulating material and includes a first sealing portion. The first sealing portion is located between the wall portion and the first limiting portion in the thickness direction of the wall portion, and the first sealing portion extends beyond the first limiting portion in the radial direction of the cylindrical battery cell in a direction away from the central axis of the cylindrical battery cell. At least a portion of the first sealing portion and the first limiting portion are accommodated in the through hole. A first gap 30 is formed between the first sealing portion 251 and the hole wall surface of the through hole 2711 along the radial direction of the cylindrical battery cell 20.

[0399] The sealing element 25 is made of insulating material, and the sealing element 25 is also configured to insulate and isolate the electrode terminal 22 and the wall portion 211, so that the electrode terminal 22 is insulated and installed on the wall portion 211.

[0400] For example, the material of the seal 25 can be various, such as silicone, plastic or rubber.

[0401] It should be noted that the first sealing portion 251 is located between the wall portion 211 and the first limiting portion 2211 in the thickness direction X of the wall portion, and the first sealing portion 251 extends beyond the first limiting portion 2211 in the radial direction of the cylindrical battery cell 20 away from the central axis of the cylindrical battery cell 20. That is to say, a portion of the first sealing portion 251 is located between the wall portion 211 and the first limiting portion 2211 in the thickness direction X of the wall portion, and in the projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of a portion of the first sealing portion 251 surrounds the outer periphery of the orthographic projection of the first limiting portion 2211, such that the projection of the outer edge of the first limiting portion 2211 in the thickness direction X of the wall portion is located inside the first sealing portion 251 of the sealing member 25.

[0402] In this embodiment, the cylindrical battery cell 20 is further provided with a sealing member 25, which is disposed between the electrode terminal 22 and the wall portion 211. This allows the sealing member 25 to seal the gap between the electrode terminal 22 and the wall surface of the mounting hole 2111, thereby mitigating the risk of leakage from the mounting hole 2111 during use. The sealing member includes a first sealing portion disposed between the wall portion and the first limiting portion. By configuring at least a portion of the first sealing portion and the first limiting portion to be accommodated within the through hole, the sealing effect of the sealing member 25 on the electrode terminal 22 and the wall portion 211 is further improved. A first gap 30 is formed between the first sealing portion 251 of the sealing member 25 and the wall surface of the through hole 2711, which facilitates the assembly of the first sealing portion 251 of the sealing member 25 into the through hole 2711. This reduces the interference between the first sealing portion 251 of the sealing member 25 and the first insulating portion 271 of the first insulating member 27, thereby effectively reducing the assembly difficulty of the cylindrical battery cell 20. In addition, the seal 25 is made of insulating material, which allows the seal 25 to achieve insulation isolation between the electrode terminal 22 and the wall of the mounting hole 2111 while sealing the gap between them. This helps to reduce the risk of short circuit between the electrode terminal 22 and the wall 211.

[0403] According to some embodiments of this application, referring to FIG6, the cylindrical battery cell 20 may further include a second insulating member 29, which is located between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion, and the projection of the second insulating member 29 in the thickness direction X of the wall portion covers the first gap 30.

[0404] The second insulating member 29 serves to block the first gap 30 between the sealing member 25 and the hole wall of the through hole 2711 between the wall portion 211 and the first current collecting member 24. The projection of the second insulating member 29 in the thickness direction X of the wall portion covers the first gap 30. That is, the projection of the first gap 30 in the thickness direction X of the wall portion is located inside the second insulating member 29.

[0405] The second insulating member 29 is located between the wall portion 211 and the first current collector 24 in the thickness direction X of the wall portion. The second insulating member 29 may be a structure disposed between the wall portion 211 and the first insulating portion 271, or a structure disposed between the first insulating portion 271 and the first current collector 24, or a structure disposed in the through hole 2711.

[0406] For example, the material of the second insulating element 29 can be various, such as rubber, plastic or silicone.

[0407] In this embodiment, by providing a second insulating member 29 between the wall portion 211 and the first current collector 24, and the projection of the second insulating member 29 in the thickness direction X of the wall portion covers the first gap 30 between the first sealing portion 251 and the first insulating portion 271, the second insulating member 29 can shield the first gap 30, thereby increasing the creepage distance between the wall portion 211 and the first current collector 24 at the first gap 30. This effectively mitigates the risk of short circuits or electrical breakdowns between the wall portion 211 and the first current collector 24 at the first gap 30, thereby improving the reliability of the cylindrical battery cell 20.

[0408] According to some embodiments of this application, as shown in Figures 6 and 13, the second insulating member 29 protrudes from the wall surface of the through hole 2711.

[0409] The second insulating member 29 protrudes from the wall of the through hole 2711. That is, the second insulating member 29 is located inside the through hole 2711 and connected to the wall of the through hole 2711. Optionally, the second insulating member 29 can be integrally formed with the first insulating part 271 or it can be a separate structure. For example, the second insulating member 29 can be connected to the wall of the through hole 2711 by adhesive or snap-fit.

[0410] In this embodiment, by configuring the second insulating member 29 as a structure protruding from the hole wall of the through hole 2711 of the first insulating part 271, the second insulating member 29 is connected to the hole wall of the through hole 2711 of the first insulating part 271. This allows the second insulating member 29 to share a portion of the space with the first insulating part 271 in the thickness direction X of the wall. This helps to alleviate the phenomenon that the second insulating member 29 occupies the space between the wall part 211 and the first insulating part 271 or the first current collector 24 and the first insulating part 271 in the thickness direction X of the wall. This improves the utilization rate of the internal space of the cylindrical battery cell 20 and increases the energy density of the cylindrical battery cell 20.

[0411] In some embodiments, as shown in FIG13, the second insulating member 29 and the first insulating part 271 are integrally formed, that is, the second insulating member 29 and the first insulating part 271 are an integral structure formed by an integral molding process, such as injection molding or extrusion molding. Correspondingly, the second insulating member 29 is a protruding bulge structure protruding on the hole wall surface of the through hole 2711, and the second insulating member 29 is an annular structure extending circumferentially along the through hole 2711.

[0412] In this embodiment, by setting the second insulating member 29 and the first insulating portion 271 of the first insulating member 27 as an integrally formed structure, on the one hand, the reliability and stability of the second insulating member 29 protruding from the hole wall of the through hole 2711 of the first insulating portion 271 can be improved, which helps to reduce the risk of the second insulating member 29 falling off the first insulating portion 271 during use, thereby improving the reliability of the second insulating member 29 blocking the first gap 30. On the other hand, it can reduce the difficulty of setting the second insulating member 29 on the hole wall of the through hole 2711 of the first insulating portion 271, which helps to reduce the manufacturing difficulty of the cylindrical battery cell 20.

[0413] According to some embodiments of this application, referring to Figures 14 and 15, Figure 14 is a cross-sectional view of a cylindrical battery cell 20 provided in some embodiments of this application, and Figure 15 is a partial enlarged view of point B of the cylindrical battery cell 20 shown in Figure 14. Along the thickness direction X of the wall portion, a second insulating member 29 is disposed between the first insulating portion 271 and the first current collector 24. That is, the second insulating member 29 is located on the side of the first insulating portion 271 facing the first current collector 24 in the thickness direction X of the wall portion.

[0414] In this embodiment, by placing the second insulating member 29 between the first insulating part 271 and the first current collector 24, it is beneficial to reduce the assembly difficulty of the second insulating member 29 and improve the production efficiency of the cylindrical battery cell 20.

[0415] In some embodiments, please continue to refer to FIG15, the second insulating member 29 is connected to the surface of the first current collector 24 facing the wall portion 211.

[0416] For example, the second insulating member 29 is bonded to the surface of the first current collector 24 facing the wall portion 211. The second insulating member 29 may be insulating tape, insulating paper or insulating film, etc., bonded to the first current collector 24.

[0417] In this embodiment, by setting the second insulating member 29 to be connected to the surface of the first current collector 24 facing the wall portion 211, on the one hand, the stability and reliability of the second insulating member 29 being disposed between the first insulating portion 271 and the first current collector 24 can be improved, which is beneficial to reduce the phenomenon of the second insulating member 29 moving or shifting during use. On the other hand, it is possible to set the second insulating member 29 on the first current collector 24 and then assemble it together with the first current collector 24 into the housing 21, which is beneficial to reduce the assembly difficulty of the second insulating member 29 and optimize the production cycle of the cylindrical battery cell 20.

[0418] Of course, the assembly structure of the second insulating member 29 is not limited to this. In other embodiments, the assembly structure of the second insulating member 29 can also be other structures. For example, the second insulating member 29 is connected to the surface of the first insulating part 271 facing the first current collector 24.

[0419] For example, the second insulating member 29 may be a structure that is bonded to the surface of the first insulating part 271 facing the first current collector 24, and the second insulating member 29 may be an insulating tape, insulating paper or insulating film, etc., bonded to the first insulating part 271.

[0420] In this embodiment, by configuring the second insulating member 29 as a structure connected to the surface of the first insulating part 271 facing the first current collector 24, on the one hand, the stability and reliability of the second insulating member 29 disposed between the first insulating part 271 and the first current collector 24 can be improved, which is beneficial to reduce the phenomenon of the second insulating member 29 moving or shifting during use. On the other hand, the second insulating member 29 can be assembled onto the first insulating part 271 first and the first gap 30 can be blocked before the first current collector 24 is assembled, which is beneficial to reduce the assembly difficulty of the second insulating member 29 and improve the effect of the second insulating member 29 in blocking the first gap 30.

[0421] In some embodiments, referring to FIG15, the orthographic projection of the terminal connection area 243 and the orthographic projection of the second insulating member 29 do not overlap in the projection plane perpendicular to the thickness direction X of the wall. That is, in the structure where the second insulating member 29 is located between the first current collector 24 and the first insulating portion 271, the projections of the terminal connection area 243 and the second insulating member 29 in the thickness direction X of the wall do not overlap.

[0422] In this embodiment, by setting the terminal connection area 243 and the second insulating member 29 to a structure in which their projections in the thickness direction X of the wall do not overlap, the obstruction and interference of the second insulating member 29 on the terminal connection area 243 can be reduced, which helps to reduce the connection difficulty between the terminal connection area 243 and the electrode terminal 22, and can improve the assembly quality between the terminal connection area 243 and the electrode terminal 22.

[0423] According to some embodiments of this application, referring to FIG15, the terminal connection area 243 is welded to the electrode terminal 22 to form a connection portion 28. The connection portion 28 and the second insulating member 29 are arranged radially on the cylindrical battery cell 20 with a spacing greater than or equal to 5 mm.

[0424] The connecting portion 28 and the second insulating member 29 are arranged radially on the cylindrical battery cell 20 with a spacing greater than or equal to 5 mm. That is, in the projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the connecting portion 28 and the orthographic projection of the second insulating member 29 are arranged radially on the cylindrical battery cell 20 with a spacing greater than or equal to 5 mm.

[0425] For example, the radial spacing between the connecting portion 28 and the second insulating member 29 on the cylindrical battery cell 20 can be 5mm, 5.1mm, 5.2mm, 5.5mm, 5.8mm, 6mm, 6.2mm, 6.5mm, 6.8mm, 7mm, 7.2mm, 7.5mm, 7.8mm, 8mm, 8.2mm, 8.5mm, 8.8mm or 9mm, etc.

[0426] In this embodiment, by setting the second insulating member 29 and the connecting portion 28 to be arranged radially spaced apart on the cylindrical battery cell 20 with a spacing greater than or equal to 5 mm, the radial separation distance between the second insulating member 29 and the connecting portion 28 on the cylindrical battery cell 20 can be increased. This reduces the risk of the second insulating member 29 being damaged by the high temperature of the connecting portion 28 during the welding connection of the terminal connection area 243 and the electrode terminal 22 to form the connecting portion 28. Consequently, it can reduce the phenomenon of insulation failure after the second insulating member 29 is damaged, thereby improving the production quality and reliability of the cylindrical battery cell 20.

[0427] Of course, the structure of the cylindrical battery cell 20 is not limited to this. In other embodiments, the cylindrical battery cell 20 can also have other structures. For example, along the thickness direction X of the wall portion, the second insulating member 29 is disposed between the first insulating portion 271 and the wall portion 211. That is, the second insulating member 29 is located on the side of the first insulating portion 271 facing the wall portion 211 in the thickness direction X of the wall portion.

[0428] In this embodiment, by placing the second insulating member 29 between the first insulating portion 271 and the wall portion 211, it is beneficial to reduce the obstruction and interference between the second insulating member 29 and the terminal connection area 243, thereby reducing the connection difficulty between the terminal connection area 243 and the electrode terminal 22.

[0429] Optionally, the second insulating member 29 is connected to the surface of the wall portion 211 facing the first insulating portion 271.

[0430] For example, the second insulating member 29 is adhered to the surface of the wall portion 211 facing the first insulating portion 271. The second insulating member 29 may be insulating tape, insulating paper, or insulating film, etc., adhered to the wall portion 211. Of course, in some embodiments, the second insulating member 29 may also be an insulating coating, etc., applied to the surface of the wall portion 211 facing the first insulating portion 271.

[0431] In this embodiment, by setting the second insulating member 29 to be connected to the surface of the wall portion 211 facing the first insulating portion 271, it is beneficial to improve the stability and reliability of the second insulating member 29 disposed between the first insulating portion 271 and the wall portion 211, so as to reduce the phenomenon of the second insulating member 29 shifting or displacing during use.

[0432] Optionally, in an embodiment where the second insulating member 29 is disposed between the first insulating portion 271 and the wall portion 211, in a projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the second insulating member 29 partially overlaps with the orthographic projection of the first sealing portion 251 of the sealing member 25. That is, a portion of the second insulating member 29 is located between the first sealing portion 251 and the wall portion 211 of the sealing member 25 in the thickness direction X of the wall portion, such that the wall portion 211 and the first sealing portion 251 form a structure that clamps a portion of the second insulating member 29.

[0433] In this embodiment, by setting the projections of the second insulating member 29 and the first sealing portion 251 of the sealing member 25 on the thickness direction X of the wall portion to an overlapping structure, a portion of the second insulating member 29 is located between the first sealing portion 251 of the sealing member 25 and the wall portion 211 on the thickness direction X of the wall portion. This can further improve the stability and reliability of the second insulating member 29 disposed between the wall portion 211 and the first insulating portion 271, thereby further reducing the phenomenon of the second insulating member 29 shifting or displacing during use. On the other hand, it can further improve the shielding effect of the second insulating member 29 on the first gap 30, thereby further reducing the risk of short circuit or electrical breakdown between the wall portion 211 and the first current collector 24 at the first gap 30.

[0434] According to some embodiments of this application, referring to Figures 14 and 15, in a projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the second insulating member 29 partially overlaps with the orthographic projection of the first insulating portion 271. That is, in the thickness direction X of the wall portion, portions of the second insulating member 29 and the first insulating portion 271 are stacked on top of each other. Correspondingly, the second insulating member 29 is disposed in the thickness direction X of the wall portion between the wall portion 211 and the first insulating portion 271, or between the first current collector 24 and the first insulating portion 271.

[0435] In this embodiment, by setting the projection of the second insulating member 29 in the thickness direction X of the wall portion to partially overlap with the first insulating portion 271, the second insulating member 29 is stacked on one side of the first insulating portion 271 in the thickness direction X of the wall portion, so that the second insulating member 29 and the first insulating portion 271 have overlapping areas, thereby improving the shielding effect of the second insulating member 29 on the first gap 30, and further mitigating the risk of short circuit or electrical breakdown of the wall portion 211 and the first current collector 24 at the first gap 30.

[0436] According to some embodiments of this application, referring to Figures 7 and 10, and further referring to Figures 16 and 17, Figure 16 is a cross-sectional view of a cylindrical battery cell 20 provided in some embodiments of this application, and Figure 17 is a partial enlarged view of point C of the cylindrical battery cell 20 shown in Figure 16. The first current collector 24 has a hollow area 246. Along the thickness direction X of the wall portion, the wall portion 211 has an exposed area 2112 corresponding to the first gap 30 in the thickness direction X of the wall portion, and the projected portion of the exposed area 2112 is located within the hollow area 246.

[0437] The current collection body area 241 of the first current collection member 24 is an annular structure surrounding the terminal connection area 243, so that the current collection body area 241 is enclosed to form an inner peripheral hole. As shown in Figures 7 and 10, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projections of the terminal connection area 243, the tab connection area 244, the elastic area 242 and the base area 245 of the first current collection member 24 are all located in the inner peripheral hole. The area of ​​the inner peripheral hole that is not covered by the orthographic projections of the terminal connection area 243, the tab connection area 244, the elastic area 242 and the base area 245 is the hollow area 246 of the first current collection member 24.

[0438] Along the thickness direction X of the wall portion, the wall portion 211 has an exposed area 2112 that corresponds to the first gap 30 in the thickness direction X of the wall portion. In other words, the portion of the wall portion 211 projected into the first gap 30 in the thickness direction X of the wall portion is the exposed area 2112 of the wall portion 211.

[0439] Along the thickness direction X of the wall portion, the projection of the exposed area 2112 is located within the hollow area 246. That is, the projection of the exposed area 2112 corresponding to the first gap 30 of the wall portion 211 is located within the hollow area 246 of the first current collecting member 24. For example, referring to FIG17, in the embodiment of this application, the projection of the exposed area 2112 of the wall portion 211 along the thickness direction X of the wall portion is located within the elastic area 242, while the other parts are all located within the hollow area 246 of the first current collecting member 24.

[0440] In this embodiment, by forming a hollow area 246 on the first current collector 24, and setting the exposed area 2112 of the wall portion 211 corresponding to the first gap 30 to be located within the hollow area 246 in the thickness direction X of the wall portion, it is beneficial to reduce the area of ​​the first current collector 24 in the thickness direction X of the wall portion corresponding to the first gap 30, thereby further mitigating the risk of short circuit or electrical breakdown between the wall portion 211 and the first current collector 24 at the first gap 30.

[0441] In some embodiments, referring to FIG17, the orthographic projection of the exposed area 2112 and the orthographic projection of the first tab 232 do not overlap in the projection plane perpendicular to the thickness direction X of the wall portion. That is, the projections of the exposed area 2112 of the wall portion 211 and the first tab 232 in the thickness direction X of the wall portion do not overlap.

[0442] The first electrode tab 232 is provided with a clearance hole 2323, which extends through both sides of the first electrode tab 232 along the thickness direction X of the wall. Correspondingly, the projection of the exposed area 2112 on the thickness direction X of the wall is located within the clearance hole 2323, so as to ensure that the exposed area 2112 of the wall 211 and the projection of the first electrode tab 232 on the thickness direction X of the wall do not overlap.

[0443] It should be noted that in the embodiment where the first electrode tab 232 is provided with a clearance portion 2322, the clearance hole 2323 can also be a clearance portion 2322. Correspondingly, in the embodiment where the electrode assembly 23 is provided with a central through hole 234, and the central through hole 234 includes a first hole segment 2341 located in the main body portion 231 and a second hole segment 2342 located in the first electrode tab 232, the second hole segment 2342 is a clearance hole 2323.

[0444] In this embodiment, by setting the projections of the exposed area 2112 and the first electrode 232 on the thickness direction X of the wall to be non-overlapping, the projection of the first electrode 232 on the thickness direction X of the wall does not fall into the first gap 30. This effectively reduces the risk of short circuit between the first electrode 232 and the wall 211 after the first electrode 232 is inserted into the first gap 30, and also reduces the risk of electrical breakdown between the first electrode 232 and the wall 211 at the first gap 30.

[0445] According to some embodiments of this application, as shown in Figures 6, 15 and 17, the first insulating portion 271 is bonded to the wall portion 211.

[0446] For example, the first insulating part 271 can be bonded to the surface of the wall part 211 facing the first insulating part 271 by means of adhesive, double-sided tape or hot melt adhesive.

[0447] In this embodiment, by setting the first insulating part 271 to be bonded to the wall part 211, the assembly difficulty between the first insulating part 27 and the wall part 211 can be reduced, thereby reducing the assembly difficulty of the cylindrical battery cell 20. On the other hand, the assembly stability of the first insulating part 27 disposed in the outer casing 21 can be improved, which is beneficial to reducing the risk of the first insulating part 27 shifting or shaking during use.

[0448] In some embodiments, as shown in Figures 4, 6, and 13, the first insulating member 27 may further include a second insulating portion 272, which surrounds the first insulating portion 271, and the second insulating portion 272 and the first insulating portion 271 together define a receiving space 273. The first current collector 24 is received within the receiving space 273, and the first electrode tab 232 is received within the receiving space 273 along the thickness direction X of the wall.

[0449] In this embodiment, the second insulating part 272 is connected to the first insulating part 271 at one end near the wall part 211 in the thickness direction X of the wall part, so that the first insulating member 27 is a hollow structure with one end open. In the embodiment where the first insulating part 271 is provided with a through hole 2711, the through hole 2711 is connected to the accommodating space 273.

[0450] The first electrode tab 232 is accommodated in the accommodating space 273 along the thickness direction X of the wall portion, that is, the first insulating member 27 is sleeved on the end of the electrode assembly 23 where the first electrode tab 232 is provided.

[0451] For example, the first insulating portion 271 and the second insulating portion 272 of the first insulating member 27 are integrally formed.

[0452] In this embodiment, the first insulating member 27 is further provided with a second insulating part 272 surrounding the first insulating part 271, and the first insulating part 271 and the second insulating part 272 together form a receiving space 273 for accommodating the first current collector 24 and the first tab 232. The cylindrical battery cell 20 with this structure is convenient for assembling the first insulating member 27. Only one end of the electrode assembly 23 with the first tab 232 needs to be inserted into the receiving space 273 of the first insulating member 27 to complete the assembly between the first insulating member 27 and the electrode assembly 23, which helps to reduce the assembly difficulty between the first insulating member 27 and the electrode assembly 23. On the other hand, the second insulating part 272 can further realize the separation between the first tab 232 and the outer shell 21 and between the first current collector 24 and the outer shell 21, which helps to improve the insulation and isolation effect of the first insulating member 27 between the first tab 232 and the outer shell 21 and between the first current collector 24 and the outer shell 21, thereby reducing the risk of short circuit of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20.

[0453] In some embodiments, as shown in Figures 6 and 13, one end of the main body 231, where the first electrode tab 232 is provided, is accommodated within the accommodating space 273 along the thickness direction X of the wall. That is, the first electrode tab 232 is entirely located within the accommodating space 273 formed by the first insulating member 27 along the thickness direction X of the wall.

[0454] In this embodiment, by setting one end of the main body 231 where the first tab 232 is provided to be housed in the housing space 273 in the thickness direction X of the wall, the first tab 232 and the first current collector 24 are both housed as a whole in the housing space 273. This can further improve the insulation and isolation effect of the first insulating member 27 on the first tab 232 and the outer shell 21, as well as the first current collector 24 and the outer shell 21, thereby further reducing the risk of short circuit in the cylindrical battery cell 20 during use.

[0455] According to some embodiments of this application, referring to Figures 4 and 5, and further referring to Figure 18, Figure 18 is a structural schematic diagram of the second current collector 26 provided in some embodiments of this application. The electrode assembly 23 also includes a second tab 233, which protrudes from the end of the main body 231 away from the wall 211 along the thickness direction X of the wall. The cylindrical battery cell 20 may also include a second current collector 26, which is disposed at the end of the electrode assembly 23 away from the wall 211 in the thickness direction X of the wall and connected to the second tab 233. The housing 21 also includes a side wall 2123, which surrounds the wall 211. A protrusion 2123a is provided on the inner wall surface of the side wall 2123. The main body 231 is located between the protrusion 2123a and the wall 211 in the thickness direction X of the wall. The protrusion 2123a is connected to the second current collector 26 to electrically connect the electrode assembly 23 and the side wall 2123.

[0456] Along the thickness direction X of the wall portion, the second electrode ear 233 protrudes from the end of the main body portion 231 away from the wall portion 211. That is, the second electrode ear 233 and the first electrode ear 232 protrude from the two ends of the main body portion 231 in the thickness direction X of the wall portion, and the first electrode ear 232 is located at the end of the main body portion 231 facing the wall portion 211.

[0457] The main body 231 is located between the protrusion 2123a and the wall 211 in the thickness direction X of the wall. That is, the protrusion 2123a protruding from the inner wall surface of the side wall 2123 is located at the end of the main body 231 of the electrode assembly 23 where the second electrode tab 233 is provided in the thickness direction X of the wall.

[0458] Alternatively, the connection structure between the protrusion 2123a and the second current collector 26 can be various, such as welding connection or abutment connection.

[0459] In this embodiment, the electrode assembly 23 is further provided with a second tab 233, and the cylindrical battery cell 20 is further provided with a second current collector 26 connected to the second tab 233. A protrusion 2123a is provided on the side wall 2123 of the outer casing 21. The protrusion 2123a is located at the end of the main body 231 away from the wall 211 in the thickness direction X of the wall portion, and the second current collector 26 is connected to the protrusion 2123a. This achieves electrical connection between the side wall 2123 of the outer casing 21 and the electrode assembly 23, thereby enabling the input or output of electrical energy from the cylindrical battery cell 20. The cylindrical battery cell 20 with this structure reduces the difficulty of electrical connection between the second current collector 26 and the side wall 2123, thus reducing the assembly difficulty of the cylindrical battery cell 20. Furthermore, the protrusion 2123a in the thickness direction X of the wall portion can also provide a certain limiting effect on the main body 231 of the electrode assembly 23, which helps to reduce the movement of the electrode assembly 23 during use.

[0460] According to some embodiments of this application, as shown in Figures 5 and 18, the second current collector 26 may include a first connection region 261, a second connection region 262, and a third connection region 263. The first connection region 261 is located at the end of the electrode assembly 23 opposite to the wall portion 211 in the thickness direction X of the wall portion and is connected to the second electrode tab 233. The second connection region 262 is connected to the protrusion 2123a. The third connection region 263 connects the first connection region 261 and the second connection region 262, and is configured to deform when the first connection region 261 and the second connection region 262 move closer or further apart along the thickness direction X of the wall portion.

[0461] The first connection area 261 is located at the end of the electrode assembly 23 away from the wall 211 in the thickness direction X of the wall, that is, the first connection area 261 of the second current collector 26 is located on the side of the second tab 233 away from the main body 231 in the thickness direction X of the wall.

[0462] For example, the first connection area 261 is welded to the second electrode 233. Of course, in other embodiments, the first connection area 261 and the second electrode 233 may also be abutting each other.

[0463] The third connecting region 263 is a structure connecting the first connecting region 261 and the second connecting region 262. The third connecting region 263 is configured to deform when the first connecting region 261 and the second connecting region 262 move closer or further apart along the thickness direction X of the wall. That is, when the second current collecting member 26 is compressed or stretched in the thickness direction X of the wall, the third connecting region 263 can deform when the first connecting region 261 and the second connecting region 262 move closer or further apart. It should be noted that when the third connecting region 263 deforms, it can be elastic deformation, plastic deformation, or both. It should be noted that when the third connecting region 263 is subjected to external force and deforms, elastic deformation occurs first. When the force exceeds the elastic limit of the third connecting region 263, plastic deformation will occur.

[0464] Optionally, in Figure 18, the second current collection member 26 is provided with a plurality of second connection areas 262 and a plurality of third connection areas 263. The plurality of third connection areas 263 are arranged circumferentially along the sidewall 2123 and are all connected to the first connection area 261. Correspondingly, the plurality of second connection areas 262 are arranged circumferentially along the sidewall 2123. Each second connection area 262 is connected to the first connection area 261 through a third connection area 263, and each second connection area 262 is connected to the protrusion 2123a.

[0465] For example, the second connection area 262 is an arc-shaped structure extending circumferentially along the sidewall 2123.

[0466] For example, in FIG18, the second current collector 26 is provided with four second connection areas 262 and four third connection areas 263, and each second connection area 262 is connected to the first connection area 261 through a third connection area 263. Of course, in other embodiments, the number of second connection areas 262 of the second current collector 26 can also be two, three, five or six, etc.

[0467] Optionally, the first connecting area 261, the second connecting area 262, and the third connecting area 263 of the second current collector 26 can be an integrally formed structure or a separate but connected structure. For example, in FIG18, the first connecting area 261, the second connecting area 262, and the third connecting area 263 of the second current collector 26 are integral structures formed by integral forming processes such as stamping and cutting.

[0468] In this embodiment, the second current collector 26 is provided with a first connecting region 261, a second connecting region 262, and a third connecting region 263. The first connecting region 261 and the second connecting region 262 are respectively connected to the second electrode 233 and the protrusion 2123a, and the third connecting region 263 is connected between the first connecting region 261 and the second connecting region 262, so as to realize that the second electrode 233 is electrically connected to the side wall 2123 through the second current collector 26. The third connecting region 263 is configured to deform when the first connecting region 261 and the second connecting region 262 move closer or further apart along the thickness direction X of the wall. This allows the third connection area 263 to act as a buffer between the first connection area 261 and the second connection area 262. In the event of shaking or displacement of the electrode assembly 23, this can alleviate the rigid tension between the first connection area 261 and the second connection area 262, between the first connection area 261 and the second tab 233, and between the second connection area 262 and the protrusion 2123a. This helps to further reduce the risk of connection failure between the first connection area 261 and the second tab 233, and between the second connection area 262 and the protrusion 2123a, and also helps to reduce the phenomenon of the second current collector 26 being damaged by tension.

[0469] According to some embodiments of this application, as shown in FIG18, the third connection area 263 is bent to form a plurality of bent segments 2631, the plurality of bent segments 2631 are connected in sequence, and the bent segments 2631 located at both ends of the plurality of bent segments 2631 are respectively connected to the first connection area 261 and the second connection area 262.

[0470] The third connecting region 263 is bent to form multiple bent segments 2631, which are connected in sequence. In other words, the third connecting region 263 is a structure with a local bending, which results in multiple bent segments 2631 connected in sequence in the third connecting region 263, and each pair of adjacent bent segments 2631 are set at an acute angle, a right angle or an obtuse angle.

[0471] For example, in FIG18, the third connecting region 263 is bent to form three bent segments 2631 connected in sequence, and the two bent segments 2631 located at both ends of the three bent segments 2631 are respectively connected to the first connecting region 261 and the second connecting region 262. Of course, in other embodiments, the number of bent segments 2631 formed by bending the third connecting region 263 can also be two, four, five or six, etc.

[0472] In this embodiment, by setting the third connecting area 263 as a structure of bending to form a plurality of sequentially connected bent segments 2631, and the bent segments 2631 located at both ends of the plurality of bent segments 2631 being connected to the first connecting area 261 and the second connecting area 262 respectively, the deformation capacity of the third connecting area 263 when the first connecting area 261 and the second connecting area 262 approach or move away from each other along the thickness direction X of the wall can be increased, so as to further improve the buffering effect of the third connecting area 263 between the first connecting area 261 and the second connecting area 262, and further reduce the phenomenon of rigid tension between the first connecting area 261 and the second connecting area 262, between the first connecting area 261 and the second tab 233, and between the second connecting area 262 and the protrusion 2123a.

[0473] According to some embodiments of this application, as shown in Figures 5 and 18, the second current collector 26 includes a second connection region 262 connected to the protrusion 2123a. Along the thickness direction X of the wall portion, the second connection region 262 is located on the side of the protrusion 2123a away from the wall portion 211.

[0474] For example, the second connection area 262 of the second current collector 26 is located on the side of the protrusion 2123a away from the wall portion 211 in the thickness direction X of the wall portion, and the second connection area 262 is welded to the surface of the protrusion 2123a on the side away from the wall portion 211.

[0475] It should be noted that in other embodiments, the second connection area 262 may also be a structure located on the side of the protrusion 2123a facing the wall portion 211 and connected to the protrusion 2123a.

[0476] In this embodiment, by setting the second connection area 262 of the second current collector 26 for interconnection with the protrusion 2123a to be located on the side of the protrusion 2123a away from the wall portion 211 in the thickness direction X of the wall portion, the second connection area 262 of the second current collector 26 and the main body portion 231 of the electrode assembly 23 are respectively located on both sides of the protrusion 2123a in the thickness direction X of the wall portion. The cylindrical battery cell 20 with this structure can reduce the interference effect caused by the main body portion 231 on the connection position of the second connection area 262 and the protrusion 2123a, and can reduce the obstruction of the main body portion 231 on the second connection area 262, which is beneficial to reduce the connection difficulty between the second connection area 262 and the protrusion 2123a, thereby reducing the assembly difficulty of the cylindrical battery cell 20.

[0477] According to some embodiments of this application, the second current collector 26 is welded to the protrusion 2123a.

[0478] For example, the second connection area 262 of the second current collector 26 is welded to the protrusion 2123a.

[0479] In this embodiment, by setting the second current collector 26 and the protrusion 2123a as a welded connection, it is beneficial to improve the connection stability and reliability between the second current collector 26 and the protrusion 2123a, so as to reduce the risk of connection failure during use.

[0480] According to some embodiments of this application, referring to FIG5, the protrusion 2123a is an annular structure extending circumferentially along the sidewall 2123.

[0481] In this embodiment, by setting the protrusion 2123a as an annular structure extending circumferentially along the sidewall 2123, on the one hand, the limiting or positioning effect of the protrusion 2123a on the main body 231 of the electrode assembly 23 can be further improved; on the other hand, it can be realized that the protrusion 2123a can be connected to the second current collector 26 at any position in the circumferential direction of the sidewall 2123, so that the second current collector 26 and the protrusion 2123a can be assembled and connected to each other. This allows the assembly connection between the second current collector 26 and the protrusion 2123a to be achieved without rotating and adjusting the position and positioning of the second current collector 26 after it is assembled into the housing 21, which helps to further reduce the connection difficulty between the second current collector 26 and the protrusion 2123a, thereby effectively improving the assembly efficiency of the cylindrical battery cell 20.

[0482] According to some embodiments of this application, as shown in Figures 4 and 5, a groove 2123b is formed on the side of the sidewall 2123 facing away from the electrode assembly 23 and corresponding to the position of the protrusion 2123a.

[0483] It should be noted that in the embodiment where the protrusion 2123a is an annular structure extending circumferentially along the sidewall 2123, the groove 2123b is also an annular groove structure extending circumferentially along the sidewall 2123.

[0484] In this embodiment, by providing a groove 2123b on the side of the sidewall 2123 facing away from the electrode assembly 23 and at a position corresponding to the protrusion 2123a, the protrusion 2123a formed on the side of the sidewall 2123 facing the electrode assembly 23 can be a structure that can be formed by stamping. This results in a protrusion 2123a being formed on the side of the sidewall 2123 facing the electrode assembly 23, and a groove 2123b being formed on the other side at a position corresponding to the protrusion 2123a. The cylindrical battery cell 20 with this structure can reduce the pressure on the sidewall 2123 facing the electrode assembly 23. The difficulty of forming a protrusion 2123a on one side of the electrode assembly 23 is beneficial to improving the production efficiency of the cylindrical battery cell 20. On the other hand, it enables the protrusion 2123a to have a hollow internal structure, thereby reducing the difficulty of assembling and connecting the protrusion 2123a and the second current collector 26. It also enables the protrusion 2123a to have the ability to deform elastically, which helps to further alleviate the rigid tension between the second current collector 26 and the protrusion 2123a, thereby reducing the risk of connection failure between the second current collector 26 and the protrusion 2123a.

[0485] According to some embodiments of this application, referring to Figures 3, 4, and 5, the outer casing 21 may include a housing 212 and an end cap 213. The housing 212 includes an integrally formed sidewall 2123 and a bottom wall 2122. The sidewall 2123 surrounds the bottom wall 2122. Along the thickness direction X of the wall portion, one end of the sidewall 2123 is connected to the bottom wall 2122, and the other end forms an opening 2121. The sidewall 2123 and the bottom wall 2122 together define a receiving cavity, within which the electrode assembly 23 is received. The end cap 213 closes the opening 2121, and the bottom wall 2122 is a wall portion 211.

[0486] The shell 212 includes an integrally formed side wall 2123 and bottom wall 2122. That is, the shell 212 is manufactured by an integral forming process, such as stamping, casting or extrusion molding. In other words, the side wall 2123 and bottom wall 2122 of the shell 212 are an integral structure.

[0487] The bottom wall 2122 is a wall portion 211, that is, the wall portion 211 is a wall of the housing 212 that is opposite to the end cap 213 in the thickness direction X of the wall portion. Correspondingly, the electrode terminal 22 is disposed on the bottom wall 2122 of the housing 212, and the first current collector 24 is disposed between the electrode assembly 23 and the bottom wall 2122 of the housing 212.

[0488] In this embodiment, by setting the wall portion 211 of the outer casing 21 as the bottom wall 2122 opposite to the end cap 213, the wall portion 211 where the electrode terminals 22 are provided can be moved away from the end cap 213. This can alleviate the phenomenon that the stress generated by the pulling or twisting of the electrode terminals 22 by other components is transmitted to the connection position of the end cap 213 and the outer casing 212, thereby reducing the risk of connection failure between the end cap 213 and the outer casing 212 and improving the stability and reliability of the cylindrical battery cell 20.

[0489] It should be noted that the structure of the cylindrical battery cell 20 is not limited to this. In some embodiments, the cylindrical battery cell 20 can also have other structures. For example, the outer casing 21 can include a housing 212 and an end cap 213. The housing 212 has a receiving cavity with an opening 2121 inside, and the electrode assembly 23 is received in the receiving cavity. The end cap 213 closes the opening 2121 and is a wall portion 211. The electrode terminal 22 is disposed on the end cap 213 of the housing 21. Correspondingly, the first current collector 24 is disposed between the electrode assembly 23 and the end cap 213.

[0490] In this embodiment, by setting the wall portion 211 of the outer casing 21 as an end cap 213 for closing the opening 2121 of the housing 212, the cylindrical battery cell 20 with this structure is convenient to assemble the electrode terminals 22 on the end cap 213, and can reduce the difficulty of assembling the first current collector 24 between the wall portion 211 and the electrode assembly 23, thereby reducing the manufacturing difficulty of the cylindrical battery cell 20 and improving the production efficiency of the cylindrical battery cell 20.

[0491] According to some embodiments of this application, this application also provides a battery device 100, which includes a cylindrical battery cell 20 of any of the above embodiments.

[0492] As shown in Figure 2, the battery device 100 may also include a housing 10, in which cylindrical battery cells 20 are housed.

[0493] In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, the first housing body 11 and the second housing body 12 covering each other, the first housing body 11 and the second housing body 12 together defining an assembly space for accommodating the cylindrical battery cell 20.

[0494] Optionally, the second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure. The first box body 11 covers the open side of the second box body 12 so that the first box body 11 and the second box body 12 together define the assembly space; the first box body 11 and the second box body 12 can also be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0495] Of course, the box 10 formed by the first box body 11 and the second box body 12 can be of various shapes, such as a cylinder or a cuboid. For example, in Figure 2, the box 10 is a cuboid structure.

[0496] Optionally, the cylindrical battery cell 20 disposed within the housing 10 can be one or more. For example, in Figure 2, the housing 10 of the battery device 100 contains multiple cylindrical battery cells 20. These cells can be connected in series, parallel, or a combination thereof. A combination thereof means that some of the cylindrical battery cells 20 are connected in series and others in parallel. The multiple cylindrical battery cells 20 can be directly connected in series, parallel, or a combination thereof, and then the entire assembly of the multiple cylindrical battery cells 20 is housed within the housing 10. Alternatively, the battery device 100 can also consist of multiple cylindrical battery cells 20 first connected in series, parallel, or a combination thereof to form a battery module, and then these battery modules are connected in series, parallel, or a combination thereof to form a whole, which is then housed within the housing 10.

[0497] The battery device 100 may also include other structures. For example, the battery device 100 may also include a busbar component that connects multiple cylindrical battery cells 20 to achieve electrical connection between the multiple cylindrical battery cells 20.

[0498] It should be noted that in some embodiments, the battery device 100 may not have a housing 10. The battery device 100 includes multiple cylindrical battery cells 20, and the battery device 100 composed of multiple cylindrical battery cells 20 can be directly mounted onto the electrical device to provide power to the electrical device through the multiple cylindrical battery cells 20. That is, the housing 10 can be part of the electrical device. Taking a vehicle 1000 as an example, the housing 10 can be part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 can be at least a part of the floor of the vehicle 1000, or a portion of the housing 10 can be at least a part of the crossbeams and longitudinal beams of the vehicle 1000.

[0499] According to some embodiments of this application, this application also provides an electrical device, which includes a cylindrical battery cell 20 of any of the above schemes, and the cylindrical battery cell 20 is used to provide electrical energy to the electrical device.

[0500] The electrical device can be any of the aforementioned devices or systems that utilize cylindrical battery cells 20.

[0501] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0502] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A cylindrical battery cell, comprising: The outer casing has a wall portion, the thickness direction of which is axial with that of the cylindrical battery cell; Electrode terminals are disposed on the wall portion; An electrode assembly is housed within the housing. The electrode assembly includes a main body and a first electrode tab, the first electrode tab protruding from one end of the main body facing the wall. as well as A first current collector is housed within the housing. The first current collector includes a current collector body region, an elastic region, and a terminal connection region. At least a portion of the current collector body region is disposed between the wall and the first electrode tab in the thickness direction of the wall, and the current collector body region is electrically connected to the first electrode tab. The elastic region is connected to the current collector body region and the terminal connection region at opposite ends in its extension direction, respectively. The terminal connection region is connected to the electrode terminal.

2. The cylindrical battery cell of claim 1, wherein, In the projection plane perpendicular to the thickness direction of the wall, the orthographic projection of the terminal connection area and the orthographic projection of the current collection body area do not overlap.

3. The cylindrical battery cell according to claim 1 or 2, wherein, In the projection plane perpendicular to the thickness direction of the wall, the orthographic projection of the elastic zone and the orthographic projection of the main flow collection zone do not overlap.

4. The cylindrical battery cell of any one of claims 1-3, wherein, The electrode terminals and the terminal connection area are arranged along the thickness direction of the wall portion. Along the thickness direction of the wall portion, the terminal connection area has a first surface facing away from the main body portion, and the electrode terminal has a connection surface facing the main body portion. The connection surface is connected to the first surface.

5. The cylindrical battery cell of claim 4, wherein, Along the thickness direction of the wall portion, the flow collection body region has a second surface that is away from the main body portion, and the second surface is further away from the main body portion than the first surface.

6. The cylindrical battery cell of claim 5, wherein, Along the thickness direction of the wall portion, the terminal connection area has a third surface facing the main body portion, and the current collection main body area has a fourth surface facing the main body portion, the fourth surface being further away from the main body portion than the third surface.

7. The cylindrical battery cell according to claim 5 or 6, wherein The first electrode has a fifth surface facing the first current collecting member in the thickness direction of the wall portion, the current collecting body area abuts against the fifth surface, and the fifth surface is provided with a relief portion that is recessed away from the electrode terminal in the thickness direction of the wall portion. Wherein, at least a portion of the terminal connection area is accommodated within the clearance portion along the thickness direction of the wall portion.

8. The cylindrical battery cell of claim 4, wherein, Along the thickness direction of the wall portion, the flow collection main body region has a second surface facing away from the main body portion, and the second surface is closer to the main body portion than the first surface.

9. The cylindrical battery cell of any one of claims 5-8, wherein, At least a portion of the elastic zone deforms and bends.

10. The cylindrical battery cell of any one of claims 1-9, wherein, Along the thickness direction of the wall portion, the first electrode tab has a fifth surface facing the wall portion, and the current collection body region abuts against the fifth surface; The fifth surface is provided with a relief portion that is recessed in the thickness direction of the wall portion away from the electrode terminal, and the projection of the terminal connection area in the thickness direction of the wall portion is located within the relief portion.

11. The cylindrical battery cell of claim 10, wherein, Along the thickness direction of the wall portion, at least a portion of the terminal connection area is accommodated within the clearance portion.

12. The cylindrical battery cell according to claim 10 or 11, wherein, Along the thickness direction of the wall portion, at least a portion of the projection of the elastic zone lies within the clearance portion.

13. The cylindrical battery cell of claim 12, wherein, The clearance portion has a clearance opening formed on the fifth surface. The clearance portion includes a first circumferential surface surrounding the clearance opening. Along the thickness direction of the wall portion, the clearance opening is formed at one end of the first circumferential surface connected to the fifth surface. The first circumferential surface is inclined from the clearance opening toward the central axis of the cylindrical battery cell. In a projection plane perpendicular to the thickness direction of the wall, the orthographic projection of the elastic zone and the orthographic projection of the first circumferential surface at least partially overlap.

14. The cylindrical battery cell of claim 13, wherein, The first circumferential surface is a conical surface.

15. The cylindrical battery cell of any one of claims 10-14, wherein, The electrode assembly has a central through hole that extends through both ends of the electrode assembly along the thickness direction of the wall portion, and the clearance portion is a part of the central through hole.

16. The cylindrical battery cell of claim 15, wherein, The central through hole includes a first hole segment and a second hole segment that are interconnected. At least a portion of the first hole segment is located inside the main body, and the second hole segment is located inside the first electrode tab. The second hole segment is the clearance portion. The minimum diameter of the second hole segment is greater than the diameter of the first hole segment.

17. The cylindrical battery cell of any one of claims 1-16, wherein, The terminal connection area is connected to the current collection body area only through one of the elastic areas.

18. The cylindrical battery cell of any one of claims 1-16, wherein, The first current collector includes a plurality of elastic regions, and the terminal connection area is connected to the current collector body area through the plurality of elastic regions.

19. The cylindrical battery cell of any one of claims 1-18, wherein, The current collection body area, the elastic area, and the terminal connection area are integrally formed.

20. The cylindrical battery cell of any one of claims 1-19, wherein, The Vickers hardness of the elastic zone is greater than or equal to 10 and less than or equal to 70.

21. The cylindrical battery cell of any one of claims 1-20, wherein, The material of the elastic zone includes aluminum.

22. The cylindrical battery cell of any one of claims 1-21, wherein, The current collection body area is an annular structure surrounding the terminal connection area. The terminal connection area and the current collection body area are spaced apart, and the elastic area is connected at opposite ends in its extension direction to the outer peripheral surface of the terminal connection area and the inner peripheral surface of the current collection body area, respectively.

23. The cylindrical battery cell of claim 22, wherein, In a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the elastic zone extends radially along the cylindrical battery cell.

24. The cylindrical battery cell of claim 23, wherein, The elastic region is connected to the current collection body area and the terminal connection area at opposite ends in its extension direction, and the elastic region has a dimension D in its extension direction, and the radius of the current collection body area is R, satisfying 0.4R≤D≤0.95R.

25. The cylindrical battery cell of claim 24, wherein, 8mm≤D≤25mm.

26. The cylindrical battery cell of any one of claims 23-25, wherein, The first current collecting component further includes a base region, and the elastic region is connected to the current collecting main body region through the base region. In the projection plane perpendicular to the thickness direction of the wall, the width of the orthographic projection of the base region in the circumferential direction of the current collecting main body region is greater than the width of the orthographic projection of the elastic region in the circumferential direction of the current collecting main body region.

27. The cylindrical battery cell of claim 26, wherein, The base region has a first end and a second end, the first end being connected to the elastic region and the second end being connected to the main flow collection region; In the projection plane perpendicular to the thickness direction of the wall portion, the width of the orthographic projection of the base region in the circumferential direction of the current collection body region gradually increases from the first end to the second end.

28. The cylindrical battery cell of any one of claims 22-27, wherein, The first current collection component further includes: The tab connection area is connected to the inner circumferential surface of the current collector body area, and the tab connection area is connected to the first tab to electrically connect the current collector body area and the first tab.

29. The cylindrical battery cell of claim 28, wherein, The tab connection area extends radially along the cylindrical battery cell.

30. The cylindrical battery cell of claim 28 or 29, wherein, In the projection plane perpendicular to the thickness direction of the wall portion, the orthographic projections of the terminal connection area and the elastic area do not overlap with the orthographic projection of the tab connection area.

31. The cylindrical battery cell of any one of claims 28-30, wherein, The first current collector includes a plurality of tab connection areas, which are arranged at intervals along the circumferential direction of the current collector body area.

32. The cylindrical battery cell of any one of claims 1-31, wherein, The terminal connection area is welded to the electrode terminal at one end of the wall portion near the main body portion in the thickness direction.

33. The cylindrical battery cell of claim 32, wherein, The electrode assembly has a central through hole that extends through both ends of the electrode assembly along the thickness direction of the wall portion; The terminal connection area is welded to the electrode terminal to form a connection part, and the projection of the connection part is located in the central through hole along the thickness direction of the wall.

34. The cylindrical battery cell of any one of claims 1-33, wherein, The electrode terminals include: Terminal body, connected to the wall portion; A protrusion is connected to the terminal body. Along the thickness direction of the wall portion, the protrusion protrudes from one end of the terminal body facing the main body portion, and the end of the protrusion near the main body portion is connected to the terminal connection area.

35. The cylindrical battery cell of claim 34, wherein, The terminal body has a first limiting portion and a second limiting portion. The first limiting portion and the second limiting portion are spaced apart along the thickness direction of the wall portion, and at least a portion of the wall portion is located between the first limiting portion and the second limiting portion.

36. The cylindrical battery cell of claim 34 or 35, wherein, The cylindrical battery cell also includes: The first insulating member includes a first insulating portion, which is disposed between the wall portion and the first current collecting member in the thickness direction of the wall portion. The first insulating part is provided with a through hole, which penetrates both sides of the first insulating part in the thickness direction of the wall part. Along the thickness direction of the wall part, the electrode terminal extends into the through hole, and the protrusion protrudes from the surface of the first insulating part facing the first current collector.

37. The cylindrical battery cell of any one of claims 1-36, wherein, The cylindrical battery cell also includes: The first insulating member includes a first insulating portion, which is disposed between the wall portion and the first current collecting member in the thickness direction of the wall portion to insulate and isolate the wall portion and the first current collecting member; The first insulating part is provided with a through hole, which penetrates both sides of the first insulating part in the thickness direction of the wall part, and the electrode terminal extends into the through hole along the thickness direction of the wall part.

38. The cylindrical battery cell of claim 37, wherein, The electrode terminals and the terminal connection area are arranged along the thickness direction of the wall portion. Along the thickness direction of the wall portion, the terminal connection area has a first surface facing away from the main body portion, and the electrode terminals have a connection surface facing the main body portion. The connection surface and the first surface are welded together. Along the thickness direction of the wall portion, the first insulating portion has a sixth surface facing the first electrode tab, and the sixth surface is further away from the main body portion than the connecting surface.

39. The cylindrical battery cell of claim 37, wherein, The electrode terminals and the terminal connection area are arranged along the thickness direction of the wall portion. Along the thickness direction of the wall portion, the terminal connection area has a first surface facing away from the main body portion, and the electrode terminals have a connection surface facing the main body portion. The connection surface and the first surface are welded together. Along the thickness direction of the wall portion, the first insulating portion has a sixth surface facing the first electrode tab, and the sixth surface is closer to the main body portion than the connecting surface.

40. The cylindrical battery cell of claim 39, wherein, Along the thickness direction of the wall portion, at least a portion of the terminal connection area is accommodated within the through hole.

41. The cylindrical battery cell of any one of claims 37-40, wherein, The wall portion is provided with a mounting hole, which penetrates the wall portion along the thickness direction. The electrode terminal is inserted into the mounting hole. The cylindrical battery cell also includes a sealing element, which is disposed between the electrode terminal and the wall portion to seal the gap between the electrode terminal and the wall surface of the mounting hole. The electrode terminal includes a first limiting portion located on the side of the wall facing the electrode assembly. The seal is made of insulating material and includes a first sealing portion. The first sealing portion is located between the wall and the first limiting portion in the thickness direction of the wall, and the first sealing portion extends beyond the first limiting portion in the radial direction of the cylindrical battery cell in a direction away from the central axis of the cylindrical battery cell. At least a portion of the first sealing portion and the first limiting portion are accommodated in the through hole. A first gap is formed between the first sealing portion and the hole wall surface of the through hole along the radial direction of the cylindrical battery cell.

42. The cylindrical battery cell of claim 41, wherein, The cylindrical battery cell also includes: The second insulating member is located between the wall portion and the first current collector in the thickness direction of the wall portion, and the projection of the second insulating member in the thickness direction of the wall portion covers the first gap.

43. The cylindrical battery cell of claim 42, wherein, The second insulating element protrudes from the wall surface of the through hole.

44. The cylindrical battery cell of claim 43, wherein, The second insulating component is integrally formed with the first insulating part.

45. The cylindrical battery cell of claim 42, wherein, Along the thickness direction of the wall portion, the second insulating member is disposed between the first insulating portion and the first current collecting member.

46. The cylindrical battery cell of claim 45, wherein, The second insulating element is connected to the surface of the first current collector facing the wall.

47. The cylindrical battery cell of claim 46, wherein, The second insulating element is connected to the surface of the first insulating portion facing the first current collecting member.

48. The cylindrical battery cell of any one of claims 45-47, wherein, In a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the terminal connection area does not overlap with the orthographic projection of the second insulating member.

49. The cylindrical battery cell of claim 48, wherein, The terminal connection area is welded to the electrode terminal to form a connection part. The connection part and the second insulating member are arranged radially on the cylindrical battery cell with a spacing greater than or equal to 5 mm.

50. The cylindrical battery cell of claim 42, wherein, Along the thickness direction of the wall portion, the second insulating member is disposed between the first insulating portion and the wall portion.

51. The cylindrical battery cell of claim 50, wherein, The second insulating member is connected to the surface of the wall portion facing the first insulating portion.

52. The cylindrical battery cell of claim 50 or 51, wherein, In a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the second insulating member partially overlaps with the orthographic projection of the first sealing portion.

53. The cylindrical battery cell of any one of claims 45-52, wherein, In a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the second insulating member partially overlaps with the orthographic projection of the first insulating portion.

54. The cylindrical battery cell of any one of claims 41-53, wherein, The first flow collector has a hollow area. Along the thickness direction of the wall, the wall has an exposed area that corresponds to the first gap in the thickness direction of the wall, and the projection of the exposed area is located within the hollow area.

55. The cylindrical battery cell of claim 54, wherein, In a projection plane perpendicular to the thickness direction of the wall portion, the orthographic projection of the exposed area does not overlap with the orthographic projection of the first tab.

56. The cylindrical battery cell of any one of claims 37-55, wherein, The first insulating part is bonded to the wall part.

57. The cylindrical battery cell of any one of claims 37-56, wherein, The first insulating element further includes: The second insulating portion is disposed around the first insulating portion, and the second insulating portion and the first insulating portion together define an accommodating space; The first current collector is housed within the housing space, and the first electrode tab is housed within the housing space along the thickness direction of the wall portion.

58. The cylindrical battery cell of claim 57, wherein, Along the thickness direction of the wall portion, the end of the main body portion having the first electrode tab is accommodated within the accommodating space.

59. The cylindrical battery cell of any one of claims 1-58, wherein, The electrode assembly further includes a second electrode tab, which protrudes from one end of the main body away from the wall portion along the thickness direction of the wall portion; The cylindrical battery cell further includes a second current collector, which is disposed in the thickness direction of the wall portion at one end of the electrode assembly away from the wall portion and connected to the second tab. The outer casing further includes a sidewall surrounding the wall portion. A protrusion is provided on the inner wall surface of the sidewall. The main body portion is located between the protrusion and the wall portion in the thickness direction of the wall portion. The protrusion is connected to the second current collector to electrically connect the electrode assembly and the sidewall.

60. The cylindrical battery cell of claim 59, wherein, The second current collector includes: The first connection area is located at one end of the electrode assembly away from the wall portion in the thickness direction of the wall portion and is connected to the second electrode tab. The second connection area is connected to the protrusion; A third connection region connects the first connection region and the second connection region, and the third connection region is configured to be deformable.

61. The cylindrical battery cell of claim 60, wherein, The third connecting region is bent to form multiple bent segments, which are connected sequentially, and the bent segments at both ends of the multiple bent segments are respectively connected to the first connecting region and the second connecting region.

62. The cylindrical battery cell of any one of claims 59-61, wherein, The second current collecting member includes a second connecting area connected to the protrusion, and along the thickness direction of the wall, the second connecting area is located on the side of the protrusion away from the wall.

63. The cylindrical battery cell of any one of claims 59-62, wherein, The second current collector is welded to the protrusion.

64. The cylindrical battery cell of any one of claims 59-63, wherein, The protrusion is a ring-shaped structure extending circumferentially along the sidewall.

65. The cylindrical battery cell of any one of claims 59-64, wherein, The sidewall is located away from the electrode assembly and has a groove formed at the position corresponding to the protrusion.

66. The cylindrical battery cell of any one of claims 1-65, wherein, The outer casing includes: The housing includes an integrally formed sidewall and a bottom wall. The sidewall surrounds the bottom wall. Along the thickness direction of the wall portion, one end of the sidewall is connected to the bottom wall, and the other end is closed to form an opening. The sidewall and the bottom wall together define a receiving cavity, and the electrode assembly is received in the receiving cavity. End cap, to close the opening; The bottom wall is the wall portion.

67. The cylindrical battery cell of any one of claims 1-65, wherein, The housing comprises: a shell having an accommodation cavity with an opening formed inside, the electrode assembly being accommodated in the accommodation cavity; an end cover closing the opening; wherein the end cover is the wall portion.

68. A battery device comprising the cylindrical battery cell of any one of claims 1-67.

69. An electrically powered device comprising the cylindrical battery cell of any one of claims 1-67, the cylindrical battery cell being used to provide electrical power.

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