Cylindrical battery cell, battery device and electric device

Abstract

The present application belongs to the technical field of batteries. Provided are a cylindrical battery cell, a battery device and an electric device. The cylindrical battery cell comprises a casing, an electrode terminal, an electrode assembly, a sealing member and a first insulating member. The electrode terminal is arranged on a wall portion of the casing. The electrode assembly comprises a main body portion and a first tab, wherein the first tab is arranged at one end of the main body portion in a protruding manner and is electrically connected to the electrode terminal. The sealing member comprises a first sealing portion located between the wall portion and a first limiting portion of the electrode terminal, and the first sealing portion extends beyond the first limiting portion in a direction away from a central axis of the cylindrical battery cell. The first insulating member comprises a first insulating portion arranged between the wall portion and the first tab, wherein the first insulating portion is formed with a through hole, and the first sealing portion is arranged in the through hole and forms a first gap with a hole wall surface of the through hole. A clearance portion is provided on a first surface of the first tab facing the wall portion, and a projection of the wall portion corresponding to an exposed area of the first gap is located in the clearance portion, so as to reduce the risk of electrical breakdown between the first tab and the wall portion.

Description

Cylindrical battery cells, battery packs and electrical devices Technical Field

[0001] 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

[0002] 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 reliability in use.

[0003] In battery technology, a cylindrical battery cell includes a casing and an electrode assembly housed within the casing. The electrode assembly has tabs that are used to electrically connect with electrode terminals disposed on the casing to realize the input or output of electrical energy of the cylindrical battery cell. However, existing cylindrical battery cells are prone to short circuits between the tabs and the casing during use, which may lead to the risk of internal short circuits in the cylindrical battery cell, thus hindering the improvement of the reliability of the cylindrical battery cell.

[0004] Summary of the Invention

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

[0006] In a first aspect, embodiments of this application provide a cylindrical battery cell, including a housing, electrode terminals, an electrode assembly, a seal, and a first insulating member; the housing has a wall portion, the thickness direction of which is the axial direction of the cylindrical battery cell, and the wall portion is provided with a mounting hole that penetrates the wall portion along its thickness direction; the electrode terminals are disposed in the mounting hole, and each electrode terminal includes a first limiting portion located on the side of the wall portion facing the interior of the housing; the electrode assembly is housed within the housing, and the electrode assembly includes a main body portion and a first tab, the first tab protruding from the end of the main body portion facing the wall portion, and the first tab being electrically connected to the electrode terminal; the seal is made of an insulating material, and the seal includes a first sealing portion located between the wall portion and the first limiting portion in the thickness direction of the wall portion, and the first sealing portion is located within the cylindrical battery cell. The first insulating member extends radially away from the central axis of the cylindrical battery cell beyond the first limiting portion; the first insulating member includes a first insulating portion disposed between the wall portion and the first electrode tab in the thickness direction of the wall portion, the first insulating portion having a through hole, the through hole penetrating the first insulating portion along the thickness direction of the wall portion, at least a portion of the first sealing portion and the first limiting portion being located within the through hole, and a first gap being formed between the first sealing portion and the hole wall surface of the through hole in the radial direction of the cylindrical battery cell; wherein, the wall portion has an exposed area corresponding to the first gap in the thickness direction of the wall portion, and the first electrode tab has a first surface facing the wall portion in the thickness direction of the wall portion, the first surface having a relief portion recessed in a direction away from the wall portion, and the projection of the exposed area in the thickness direction of the wall portion being located within the relief portion.

[0007] In the above technical solution, the sealing element includes a first sealing portion disposed between the first limiting portion and the wall portion of the electrode terminal, enabling the sealing element to seal the gap between the electrode terminal and the wall portion, thereby mitigating the risk of leakage from the mounting hole during use of the cylindrical battery cell. Furthermore, the first sealing portion of the sealing element is positioned within the through hole and extends beyond the first limiting portion in the radial direction away from the central axis of the cylindrical battery cell, creating a first gap between the first sealing portion and the wall surface of the through hole. This facilitates the assembly of the first sealing portion of the sealing element into the through hole, reducing the impact between the first sealing portion of the sealing element and the first insulating element. To prevent assembly interference between the edges, the first electrode tab has a recessed clearance portion on its first surface facing the wall. By setting the exposed area of ​​the wall corresponding to the first gap to a structure in which the projection of the wall in the thickness direction is located within the clearance portion, the first electrode tab can avoid the first gap through the clearance portion. This effectively alleviates the phenomenon of short circuit between the first electrode tab and the wall after it is inserted into the first gap, and also effectively alleviates the phenomenon of electrical breakdown between the first electrode tab and the wall at the first gap. This helps to reduce the risk of internal short circuit during use of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell.

[0008] 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.

[0009] In the above technical solution, by setting the exposed area of ​​the wall corresponding to the first gap to a structure in which the projection of the wall portion in the thickness direction and the projection of the first electrode in the thickness direction of the wall portion do not overlap, the projection of the first electrode in the thickness direction of the wall portion does not fall into the first gap. This can further alleviate the phenomenon of short circuit between the first electrode and the wall portion after the first electrode is inserted into the first gap, and can further alleviate the phenomenon of electrical breakdown between the first electrode and the wall portion at the first gap. In this way, the risk of internal short circuit during use of the cylindrical battery cell can be further reduced, thereby further improving the reliability of the cylindrical battery cell.

[0010] 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.

[0011] 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 relief part to avoid the exposed area of ​​the wall, the relief part can not only avoid the exposed area of ​​the wall, but also cooperate with the central through hole to vent, which is beneficial to improve the internal venting smoothness of the cylindrical battery cell and reduce the manufacturing difficulty of the electrode assembly.

[0012] 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 diameter of the first hole segment is smaller than the diameter of the second hole segment.

[0013] In the above technical solution, by setting the second hole segment located inside the first electrode tab as a clearance part, and setting the diameter of the first hole segment to be smaller than that of the second hole segment, the effect of the second hole segment as a clearance part in avoiding the exposed area of ​​the wall part can be improved, while also alleviating the phenomenon that the first hole segment located inside the main body occupies too much space, thereby helping to improve the energy density of the electrode assembly.

[0014] 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 diameter of the first hole segment is equal to the diameter of the second hole segment.

[0015] 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 first hole segment and the hole diameter of the second hole segment to be equal, the processing difficulty of the central through hole can be reduced while the second hole segment acts as a clearance part to avoid the exposed area of ​​the wall, thereby reducing the manufacturing difficulty of the electrode assembly.

[0016] In some embodiments, the electrode terminal includes a terminal body disposed within the mounting hole and connected to the wall portion, the terminal body including a first limiting portion; wherein the terminal body extends into the through hole along the thickness direction of the wall portion, and the seal further includes a second sealing portion located between the terminal body and the hole wall surface of the mounting hole to seal the gap between the terminal body and the hole wall surface of the mounting hole.

[0017] In the above technical solution, by setting the terminal body of the electrode terminal in the mounting hole of the wall, and setting the second sealing part of the seal to be located between the terminal body and the hole wall of the mounting hole, the seal can seal the gap between the terminal body and the hole wall of the mounting hole, thereby further improving the sealing effect of the seal between the wall and the electrode terminal, and improving the stability and reliability of the seal installed between the wall and the electrode terminal, which helps to reduce the risk of the seal falling off during use.

[0018] In some embodiments, the terminal body further includes a second limiting portion located on the side of the wall portion away from the interior of the housing, the first limiting portion and the second limiting portion being spaced apart along the thickness direction of the wall portion, and at least a portion of the wall portion being located between the first limiting portion and the second limiting portion; wherein, the seal further includes a third sealing portion located between the wall portion and the second limiting portion in the thickness direction of the wall portion to seal the gap between the wall portion and the second limiting portion.

[0019] 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 portion of the wall being 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. This allows the first limiting part and the second limiting part to cooperate in clamping the wall, thereby enabling the terminal body of the electrode terminal to be installed on the wall. The structure is simple and easy to implement and assemble. In addition, the sealing member is also provided with a third sealing part located between the second limiting part and the wall, so that the sealing member can also seal the gap between the second limiting part and the wall. This further improves the sealing effect of the sealing member between the wall and the electrode terminal, and enhances the stability and reliability of the sealing member installed between the wall and the electrode terminal, thus reducing the risk of the sealing member falling off during use.

[0020] In some embodiments, the cylindrical battery cell further includes a second insulating member; the second insulating member is located between the wall and the first tab in the thickness direction of the wall, and the projection of the second insulating member in the thickness direction of the wall covers the first gap.

[0021] In the above technical solution, by providing a second insulating member between the wall and the first tab, 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 tab at the first gap. It can also achieve a certain barrier effect between the second insulating member and the wall, thereby further mitigating the phenomenon of the first tab overlapping with the wall when inserted into the first gap or the first tab and the wall experiencing electrical breakdown at the first gap. This is beneficial to further reduce the risk of internal short circuits in cylindrical battery cells during use, thereby further improving the reliability of cylindrical battery cells.

[0022] In some embodiments, the second insulating member protrudes from the wall surface of the through hole.

[0023] In the above technical solution, by setting the second insulating member as a structure protruding from the hole wall of the through hole of the first insulating part, the second insulating member is a structure connected to the hole wall of the through hole of the first insulating part. This allows the second insulating member to share part 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 tab 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.

[0024] In some embodiments, the second insulating member is integrally formed with the first insulating portion.

[0025] 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.

[0026] In some embodiments, the cylindrical battery cell further includes a first current collector disposed between the first insulating portion and the first tab, the first current collector connecting the electrode terminal and the first tab to electrically connect the electrode terminal and the first tab; wherein, along the thickness direction of the wall portion, a second insulating member is disposed between the first insulating portion and the first current collector.

[0027] 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.

[0028] In some embodiments, the second insulating member is connected to the surface of the first current collector member facing the first insulating portion.

[0029] 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.

[0030] In some embodiments, the second insulating member is connected to the surface of the first insulating portion facing the first current collector.

[0031] 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.

[0032] In some embodiments, the first current collector includes a terminal connection area connected to the electrode terminal; wherein, in a projection plane perpendicular to the thickness direction of the wall, the orthographic projection of the terminal connection area does not overlap with the orthographic projection of the second insulating member.

[0033] In the above technical solution, by setting the terminal connection area of ​​the first current collector for interconnection with the electrode terminal to a structure in which the projection of the first current collector in the thickness direction of the wall and the projection of the second insulating member in the thickness direction of the wall do not overlap, it is possible to reduce the obstruction and interference of the second insulating member on the terminal connection area, which is beneficial to reduce the connection difficulty between the terminal connection area and the electrode terminal, and can improve the assembly quality between the terminal connection area and the electrode terminal.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] In some embodiments, the second insulating member is connected to the surface of the wall portion facing the first insulating portion.

[0039] 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 between the first insulating portion and the wall portion, so as to reduce the phenomenon of the second insulating member moving or shifting during use.

[0040] 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.

[0041] In the above technical solution, by setting the projections of the second insulating member and the first sealing member in the thickness direction of the wall to be mutually overlapping, the portion of the second insulating member is located between the first sealing member and the wall in the thickness direction of the wall. This can further improve the stability and reliability of the second insulating member between the wall and the first insulating member, 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 and the first electrode at the first gap.

[0042] 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.

[0043] 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 and the first insulating portion have overlapping areas, thereby improving the shielding effect of the second insulating member on the first gap, and further reducing the risk of short circuit or electrical breakdown of the wall portion and the first electrode at the first gap.

[0044] In some embodiments, the cylindrical battery cell further includes a first current collector; the first current collector is disposed between the first insulating portion and the first tab along the thickness direction of the wall portion, and the first current collector connects the electrode terminal and the first tab to electrically connect the first tab and the electrode terminal.

[0045] In the above technical solution, by setting a first current collector between the first insulating part and the first tab of the first insulating member, and the first current collector connecting the electrode terminal and the first tab, the insulation isolation between the first current collector and the wall is achieved by the first insulating member, while the difficulty of electrical connection between the first tab and the electrode terminal is reduced, thereby reducing the assembly difficulty of the cylindrical battery cell.

[0046] In some embodiments, the first flow collector has a hollow area, and the portion of the projection of the exposed area along the thickness direction of the wall is located within the hollow area.

[0047] 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 reducing the risk of short circuit or electrical breakdown between the wall and the first current collector at the first gap.

[0048] In some embodiments, the first current collector includes a current collector body region, a terminal connection region, and an elastic region; at least a portion of the current collector body region is disposed between the first insulating portion and the first electrode tab in the thickness direction of the wall portion, and the current collector body region is electrically connected to the first electrode tab; the terminal connection region is connected to the electrode terminal; the elastic region connects the current collector body region and the terminal connection region, and the elastic region is configured to be deformable.

[0049] 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 elastic area is connected between the current collector body area and the 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 to realize the electrical connection between the electrode terminal and the electrode assembly. The elastic area is designed to be deformable, allowing it 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. This deformability allows the terminal connection area to move along the thickness direction of the wall when subjected to compression or other phenomena, thereby absorbing the electrode terminal. The assembly error between the electrode terminal and the terminal connection area 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. In the process of the electrode assembly shaking or shifting, it can alleviate 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. 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. In this way, it can effectively improve the stability and service life of the cylindrical battery cell.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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 second 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 second surface are welded together.

[0055] 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 welding the second surface of the terminal connection area away from the main body to the connection surface of the electrode terminal facing the main body, 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 zone, the assembly error between the electrode terminals and the terminal connection area can be absorbed, thereby alleviating the welding gap between the terminal connection area and the electrode terminals, which helps to reduce the risk of poor welding between the terminal connection area and the electrode terminals, and thus improves the welding quality between the terminal connection area and the electrode terminals.

[0056] In some embodiments, along the thickness direction of the wall portion, the first insulating portion has a third surface facing the first tab, and the third surface is further away from the body portion than the connecting surface.

[0057] In the above technical solution, by setting the third 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 to weld the connecting surface of the electrode terminal to the second 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 second surface and the connecting surface. This effectively improves the welding quality between the second surface and the connecting surface, thereby reducing phenomena such as incomplete soldering between the terminal connection area and the electrode terminal.

[0058] In some embodiments, along the thickness direction of the wall portion, the flow collection body region has a fourth surface facing away from the body portion, and the fourth surface is further away from the body portion than the second surface.

[0059] In the above technical solution, by setting the fourth 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 second 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 second surface of the terminal connection area and the connection surface of the electrode terminal, which is beneficial to further improve the welding 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 fourth 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 beneficial to improve the internal space utilization of the cylindrical battery cell.

[0060] In some embodiments, along the thickness direction of the wall portion, the terminal connection area has a fifth surface facing the main body portion, and the current collection main body area has a sixth surface facing the main body portion, the sixth surface being further away from the main body portion than the fifth surface.

[0061] In the above technical solution, by further setting the fifth 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 sixth 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 second surface of the terminal connection area and the connection surface of the electrode terminal, which is conducive to further improving the welding quality between the terminal connection area and the electrode terminal.

[0062] 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.

[0063] In the above technical solution, by setting at least a portion of the terminal connection area to be accommodated within the clearance portion in the thickness direction of the wall, the cylindrical battery cell with this structure can achieve the first tab clearance of 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.

[0064] In some embodiments, along the thickness direction of the wall portion, the flow collection body region has a fourth surface facing away from the body portion, and the fourth surface is closer to the body portion than the second surface.

[0065] In the above technical solution, by setting the fourth 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 second surface of the terminal connection area away from the main body, the second 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 fourth surface of the current collection main body area. On the one hand, this facilitates the welding connection between the second 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, which is beneficial to improving the assembly quality 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 is beneficial to reducing the assembly gap between the second surface of the terminal connection area and the connection surface of the electrode terminal, thereby improving the welding quality between the terminal connection area and the electrode terminal.

[0066] In some embodiments, along the thickness direction of the wall portion, the first insulating portion has a third surface facing the first tab, and the third surface is closer to the body portion than the connecting surface.

[0067] In the above technical solution, by setting the third 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.

[0068] 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.

[0069] 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.

[0070] In some embodiments, at least a portion of the elastic region deforms and bends.

[0071] 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 second 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 second surface of the terminal connection area and the connection surface of the electrode terminal, which is beneficial to further improve the welding quality between the terminal connection area and the electrode terminal.

[0072] In some embodiments, the projection of the terminal connection area is located within the clearance portion along the thickness direction of the wall portion.

[0073] In the above technical solution, by providing a clearance portion on the first electrode tab, and setting the projections of the exposed area of ​​the wall and the terminal connection area in the thickness direction of the wall to be located within the clearance portion, the clearance portion can ensure that the projections of the exposed area of ​​the wall and the first electrode tab in the thickness direction of the wall do not overlap, while also avoiding the terminal connection area of ​​the first current collector. 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. On the one hand, this reduces the obstruction and interference of the first electrode tab on the terminal connection area, which is conducive 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 tab during use or assembly, which is conducive to reducing the phenomenon of damage to the first electrode tab, and can reduce the risk of short circuit caused by the first electrode tab being inserted backward into the body.

[0074] 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.

[0075] 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.

[0076] In some embodiments, the current collecting body abuts against the first surface, the clearance portion forms a clearance opening on the first surface, the sidewall of the clearance portion includes a first circumferential surface, and the clearance opening is formed at one end of the first circumferential surface connected to the first surface along the thickness direction of the wall portion. 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.

[0077] In the above technical solution, the first circumferential surface of the avoidance part is connected to the first surface at one end to form an avoidance opening, and the avoidance opening is located on the first 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 first surface and smaller at the end farther away from the first 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.

[0078] In some embodiments, the first circumferential surface is a conical surface.

[0079] 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.

[0080] In some embodiments, the terminal connection area is connected to the current collection body area only through one of the elastic areas.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] In some embodiments, the current collection body area, the elastic area, and the terminal connection area are integrally formed.

[0085] 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.

[0086] In some embodiments, the Vickers hardness of the elastic region is greater than or equal to 10 and less than or equal to 70.

[0087] 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.

[0088] In some embodiments, the material of the elastic region includes aluminum.

[0089] 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.

[0090] In some embodiments, the elastic region connects the current collector body region and the terminal connection region at opposite ends in its extending direction, and the area of ​​the cross-section of the elastic region perpendicular to its extending direction is S, satisfying 0.2 mm. 2 ≤S≤8mm 2 .

[0091] In the above technical solution, the area of ​​the cross-section of the elastic zone perpendicular to its extension direction is 0.2 mm. 2 up to 8mm 2 On the one hand, the area of ​​the cross-section of the elastic zone perpendicular to its extension direction is set to be greater than or equal to 0.2 mm. 2 This increases the flow area of ​​the elastic zone, thereby improving the flow capacity of the first current collector. On the other hand, the cross-sectional area of ​​the elastic zone perpendicular to its extension direction is set to be less than or equal to 8 mm². 2 It allows the elastic zone to deform better between the current collector area and the terminal connection area, which helps to improve the deformation capacity of the elastic zone.

[0092] In some embodiments, the cross-section is rectangular, and the length and width of the cross-section are L and W, respectively, satisfying that 1mm≤L≤10mm and 0.2mm≤W≤0.8mm.

[0093] In the above technical solution, by setting the length of the cross section of the elastic zone perpendicular to its extension direction to 1mm to 10mm and the width of the cross section of the elastic zone perpendicular to its extension direction to 0.2mm to 0.8mm, the elastic zone is made into a flat structure. The elastic zone with this structure can meet the flow requirements of the elastic zone, improve the deformation capacity of the elastic zone, reduce the processing difficulty of the elastic zone and reduce the space occupied by the elastic zone.

[0094] 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.

[0095] 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 being 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 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 first insulating part and the first electrode tab, which helps to improve the structural stability of the current collector body area of ​​the first current collector component located between the first insulating part and the first electrode tab.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] In some embodiments, 8mm ≤ D ≤ 25mm.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] 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.

[0107] In the above technical solution, the first current collector is further provided with a tab connection area for interconnection with the first tab, and the tab 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 tab through the tab connection area, which helps to reduce the connection difficulty between the first current collector and the first tab and can increase the connection area between the first current collector and the first tab. On the other hand, it can optimize the structural layout between the tab connection area and the current collector body area, so as to assemble the current collector body area of ​​the first current collector between the first insulating part and the first tab, which helps to improve the structural stability of the current collector body area of ​​the first current collector set between the first insulating part and the first tab.

[0108] In some embodiments, the tab connection area extends radially along the cylindrical battery cell.

[0109] 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.

[0110] 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.

[0111] 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 reducing 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.

[0112] 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.

[0113] 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.

[0114] In some embodiments, the terminal connection area is welded to the electrode terminal at one end of the wall portion near the body portion in the thickness direction.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] In some embodiments, the electrode terminal includes a terminal body and a protrusion; the terminal body is disposed in the mounting hole and connected to the wall portion, the terminal body extends into the through hole along the thickness direction of the wall portion, the sealing member is disposed between the terminal body and the wall portion, and the terminal body includes the first limiting 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.

[0119] 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 terminal body is inserted into the through hole along the thickness direction of the wall, and 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.

[0120] In some embodiments, along the thickness direction of the wall portion, the protrusion protrudes from the surface of the first insulating portion facing the first current collector.

[0121] In the above technical solution, by setting the protrusion to protrude from the surface of the first insulating part facing the first current collector in the thickness direction of the wall, the obstruction and interference of the first insulating part 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.

[0122] In some embodiments, the first insulating portion is bonded to the wall portion.

[0123] 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.

[0124] 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, along the thickness direction of the wall portion, the first electrode tab is received within the receiving space.

[0125] 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 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 separate the first electrode tab from the outer shell, which helps to improve the insulation and isolation effect of the first insulating member between the first electrode tab and the outer shell, thereby reducing the risk of short circuit in the cylindrical battery cell and improving the reliability of the cylindrical battery cell.

[0126] 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.

[0127] 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 is accommodated as a whole 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, and further reducing the risk of short circuit in the cylindrical battery cell during use.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] In some embodiments, the third connection region is bent to form a plurality of bent segments, which are connected sequentially, and the bent segments located at both ends of the plurality of bent segments are respectively connected to the first connection region and the second connection region.

[0133] In the above technical solution, by setting the third connecting area as a structure of multiple bent segments connected in sequence by bending, and the bent segments at both ends of the multiple bent segments are respectively connected to the first connecting area and the second connecting area, 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.

[0134] 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.

[0135] 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.

[0136] In some embodiments, the second current collector is welded to the protrusion.

[0137] 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.

[0138] In some embodiments, the protrusion is a ring-shaped structure extending circumferentially along the sidewall.

[0139] 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.

[0140] 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.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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 insulating component 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.

[0146] Secondly, embodiments of this application also provide a battery device, including the aforementioned cylindrical battery cell.

[0147] 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

[0148] 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.

[0149] Figure 1 is a structural schematic diagram of a vehicle provided in some embodiments of this application;

[0150] Figure 2 is an exploded view of the structure of a battery device provided in some embodiments of this application;

[0151] Figure 3 is a schematic diagram of the structure of a cylindrical battery cell provided in some embodiments of this application;

[0152] Figure 4 is an exploded view of the structure of a cylindrical battery cell provided in some embodiments of this application;

[0153] Figure 5 is a cross-sectional view of a cylindrical battery cell provided in some embodiments of this application;

[0154] Figure 6 is a partial enlarged view of point A of the cylindrical battery cell shown in Figure 5;

[0155] Figure 7 is a cross-sectional view of a first insulating member provided in some embodiments of this application;

[0156] Figure 8 is a cross-sectional view of the electrode terminals provided in some embodiments of this application;

[0157] Figure 9 is a cross-sectional view of a seal provided in some embodiments of this application;

[0158] Figure 10 is a partial cross-sectional view of an electrode assembly provided in some embodiments of this application;

[0159] Figure 11 is a cross-sectional view of a cylindrical battery cell provided in some embodiments of this application;

[0160] Figure 12 is a partial enlarged view of point B of the cylindrical battery cell shown in Figure 11;

[0161] Figure 13 is a cross-sectional view of a cylindrical battery cell provided in some embodiments of this application;

[0162] Figure 14 is a partial enlarged view of point C of the cylindrical battery cell shown in Figure 13;

[0163] Figure 15 is a schematic diagram of the structure of the first current collection component provided in some embodiments of this application;

[0164] Figure 16 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;

[0165] Figure 17 is a partial cross-sectional view of an electrode assembly provided in some embodiments of this application;

[0166] Figure 18 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;

[0167] Figure 19 is a schematic diagram of the structure of the second current collector provided in some embodiments of this application.

[0168] 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 - Terminal 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- Clearance part; 2321a- Clearance opening; 2321b- First peripheral surface; 2322- First surface; 233- Second electrode tab; 234- Central through hole; 2341- First hole segment; 2342- Second hole segment; 24- Sealing element ; 241-First sealing part; 242-Second sealing part; 243-Third sealing part; 25-First insulating member; 251-First insulating part; 2511-Through hole; 2512-Third surface; 252-Second insulating part; 253-Accommodation space; 26-First gap; 27-First current collector; 271-Current collector body area; 2711-Fourth surface; 2712-Sixth surface; 272-Terminal connection area; 2721-Second surface Surface; 2722-Fifth surface; 273-Elastic region; 274-Electrode connection region; 275-Base region; 2751-First end; 2752-Second end; 276-Hollowed-out region; 28-Second current collector; 281-First connection region; 282-Second connection region; 283-Third connection region; 2831-Bending section; 29-Second insulating component; 30-Connecting part; 200-Controller; 300-Motor; X-Thickness direction of the wall. Detailed Implementation

[0169] 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.

[0170] 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.

[0171] 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.

[0172] 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.

[0173] 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 three cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0174] 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.

[0175] In this application, "multiple" means two or more (including two).

[0176] 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.

[0177] 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.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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.).

[0182] 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.

[0183] 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.

[0184] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0185] 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.).

[0186] 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.

[0187] 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.

[0188] 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.

[0189] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0190] In some embodiments, the electrode assembly further includes an isolator disposed between the positive and negative electrodes.

[0191] 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.

[0192] 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.

[0193] 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.

[0194] 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 an electrolyte salt and a solvent.

[0195] 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.

[0196] 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.

[0197] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0198] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0199] As an example, polymer solid electrolytes can be polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0200] 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.

[0201] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0202] In some implementations, the electrode assembly has a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0203] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0204] In some implementations, the electrode assembly has a positive tab and a negative tab.

[0205] 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.

[0206] As an example, a single battery cell can be cylindrical, i.e., a cylindrical battery cell.

[0207] 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.

[0208] 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.

[0209] 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.

[0210] 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.

[0211] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0212] 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 shutting down; it can be sealed or not sealed. The first enclosure body may be a top cover or a bottom plate.

[0213] 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.

[0214] 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.

[0215] 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.

[0216] 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.

[0217] For a typical cylindrical battery cell, it usually includes a casing and an electrode assembly housed within the casing. Electrode terminals are provided on the wall of the casing, and correspondingly, a tab is formed at one end of the electrode assembly near the wall. Electrical connection between the electrode terminals and the tab enables the input or output of electrical energy into the cylindrical battery cell. In related technologies, mounting holes for assembling power supply terminals are provided on the wall, allowing one end of the electrode terminal to extend into the casing and the other end to extend outside, facilitating the input or output of electrical energy from the cylindrical battery cell. To address the short circuit problem between the electrode terminals and the wall, and the risk of leakage between them, an insulating seal is typically provided between the electrode terminals and the wall of the mounting hole. This seal seals the gap between the electrode terminals and the wall of the mounting hole, and also provides insulation between the electrode terminals and the wall. To reduce the risk of short circuit between the tab and the wall, a first insulating element is usually provided on the side of the wall facing the electrode assembly. This first insulating element can insulate and isolate the tab and the wall. However, to alleviate the interference between the first insulating element, the seal, and the electrode terminals, through holes are usually made on the first insulating element for inserting the power supply terminal and the seal. The wall surface of the through hole and the seal are spaced apart radially in the cylindrical battery cell to reduce the assembly difficulty and interference between the seal and the first insulating element. However, in the use of cylindrical battery cells with this structure, the tab may overlap with the shell when inserted into the first gap, or the tab and the shell may break down at the first gap. This means that the cylindrical battery cell is still prone to short circuit between the tab and the shell during use, which is detrimental to improving the reliability of the cylindrical battery cell.

[0218] Based on the above considerations, in order to solve the problem of low reliability in the use of cylindrical battery cells, this application provides a cylindrical battery cell, which includes a shell, electrode terminals, electrode assemblies, a seal, and a first insulating member. The shell has a wall portion, the thickness direction of which is the axial direction of the cylindrical battery cell, and a mounting hole is provided in the wall portion, penetrating the wall portion along its thickness direction. The electrode terminals are disposed in the mounting hole, and the electrode terminals include a first limiting portion located on the side of the wall portion facing the interior of the shell. The electrode assembly is housed within the shell, and the electrode assembly includes a main body portion and a first tab, the first tab protruding from the end of the main body portion facing the wall portion, and the first tab being electrically connected to the electrode terminal. The seal is made of insulating material, and the seal includes a first sealing portion, the first sealing portion being located between the wall portion and the first limiting portion in the thickness direction of the wall portion, and the first sealing portion extending 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. The first insulating member includes a first insulating portion disposed between the wall portion and the first electrode tab in the thickness direction of the wall portion. The first insulating portion has a through hole that extends through the first insulating portion in the thickness direction of the wall portion. At least a portion of the first sealing portion and the first limiting portion are located within the through hole. A first gap is formed between the first sealing portion and the hole wall surface of the through hole in the radial direction of the cylindrical battery cell. The wall portion has an exposed area corresponding to the first gap in the thickness direction of the wall portion. In the thickness direction of the wall portion, the first electrode tab has a first surface facing the wall portion. The first surface has a relief portion recessed in a direction away from the wall portion. The projection of the exposed area in the thickness direction of the wall portion is located within the relief portion.

[0219] In this type of cylindrical battery cell, the seal includes a first sealing portion disposed between a first limiting portion and a wall portion of the electrode terminal. This seal allows the seal to seal the gap between the electrode terminal and the wall portion, mitigating the risk of leakage from the mounting hole during use. The first sealing portion is positioned within the through hole and extends radially away from the central axis of the cylindrical battery cell from the first limiting portion, creating a first gap between the first sealing portion and the wall surface of the through hole. This facilitates the fitting of the first sealing portion into the through hole and reduces the contact area between the first sealing portion and the first insulating component. The assembly interference between insulating parts is resolved by providing a relief portion recessed away from the wall on the first surface of the first tab facing the wall. By setting the exposed area of ​​the wall corresponding to the first gap to a structure in which the projection of the wall in the thickness direction is located within the relief portion, the first tab can avoid the first gap through the relief portion. This effectively alleviates the phenomenon of short circuit between the first tab and the wall after it is inserted into the first gap, and also effectively alleviates the phenomenon of electrical breakdown between the first tab and the wall at the first gap. This helps to reduce the risk of internal short circuit during the use of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell.

[0220] 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 internal short circuits in the cylindrical battery cells, thereby improving the reliability of the cylindrical battery cells.

[0221] 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.

[0222] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device according to an embodiment of this application.

[0223] 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.

[0224] 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.

[0225] 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.

[0226] 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.

[0227] 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.

[0228] 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.

[0229] 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.

[0230] 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.

[0231] According to some embodiments of this application, referring to Figure 3, and further referring to Figures 4, 5, 6, 7, 8, and 9, 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; Figure 7 is a cross-sectional view of the first insulating member 25 provided in some embodiments of this application; Figure 8 is a cross-sectional view of the electrode terminal 22 provided in some embodiments of this application; and Figure 9 is a cross-sectional view of the sealing member 24 provided in some embodiments of this application. This application provides a cylindrical battery cell 20, which includes a housing 21, electrode terminals 22, electrode assemblies 23, a sealing member 24, and a first insulating member 25. The housing 21 has a wall portion 211, the thickness direction X of which is the axial direction of the cylindrical battery cell 20. The wall portion 211 is provided with a mounting hole 2111, which penetrates the wall portion 211 along the thickness direction X. Electrode terminal 22 is disposed in mounting hole 2111, and electrode terminal 22 includes a first limiting portion 2211 located on the side of wall portion 211 facing the interior of housing 21. Electrode assembly 23 is housed within housing 21, and electrode assembly 23 includes main body portion 231 and first tab 232. First tab 232 protrudes from the end of main body portion 231 facing wall portion 211 and is electrically connected to electrode terminal 22. Seal 24 is disposed between electrode terminal 22 and wall portion 211 to seal electrode terminal 22 and wall portion 211. Seal 24 is made of insulating material and includes a first sealing portion 241. The first sealing portion 241 is located between wall portion 211 and first limiting portion 2211 in the thickness direction X of wall portion, and the first sealing portion 241 extends beyond the first limiting portion 2211 in the radial direction of cylindrical battery cell 20 away from the central axis of cylindrical battery cell 20. The first insulating member 25 includes a first insulating portion 251 disposed between the wall portion 211 and the first tab 232 in the thickness direction X of the wall portion. The first insulating portion 251 is provided with a through hole 2511, which penetrates the first insulating portion 251 along the thickness direction X of the wall portion. At least a portion of the first sealing portion 241 and the first limiting portion 2211 are located in the through hole 2511. A first gap 26 is formed between the first sealing portion 241 and the hole wall surface of the through hole 2511 in the radial direction of the cylindrical battery cell 20. The wall portion 211 has an exposed area 2112 that corresponds to the first gap 26 in the thickness direction X of the wall portion. In the projection plane perpendicular to the thickness direction X of the wall portion, along the thickness direction X of the wall portion, the first tab 232 has a first surface 2322 facing the wall portion 211. The first surface 2322 is provided with a relief portion 2321 that is recessed in a direction away from the wall portion 211. The projection of the exposed area 2112 in the thickness direction X of the wall portion is located in the relief portion 2321.

[0232] 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.

[0233] 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.

[0234] The wall portion 211 is provided with a mounting hole 2111, which penetrates the wall portion 211 along the thickness direction X. That is, the mounting hole 2111 is a structure that extends along the thickness direction X of the wall portion and penetrates the surfaces of both sides of the wall portion 211.

[0235] 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.

[0236] 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.

[0237] 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.

[0238] 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.

[0239] 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 end cap 213 is circular in projection on the thickness direction X of the wall.

[0240] 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.

[0241] 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.

[0242] 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.

[0243] 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.

[0244] 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.

[0245] 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.

[0246] 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.

[0247] 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.

[0248] 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.

[0249] In this embodiment, the electrode terminal 22 serves to input or output electrical energy to the cylindrical battery cell 20, i.e., the electrode terminal 22 acts as an output electrode of the cylindrical battery cell 20. A portion of the electrode terminal 22 is disposed within the mounting hole 2111 and connected to the wall portion 211. Exemplarily, the electrode terminal 22 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy.

[0250] The electrode terminal 22 is insulatedly mounted on the wall portion 211, meaning there is no electrical connection between the electrode terminal 22 and the wall portion 211. Referring to Figures 6 and 8, the electrode terminal 22 is riveted to the wall portion 211. The electrode terminal 22 includes a terminal body 221 and a protrusion 222. The terminal body 221 passes through the mounting hole 2111 and has a first limiting portion 2211 located on the side of the wall portion 211 facing the electrode assembly 23 and a portion located on the side of the wall portion 211 facing away from the electrode assembly. The second limiting portion 2212 on one side of component 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, such that the first limiting portion 2211 and the second limiting portion 2212 can cooperate to clamp the wall portion 211, thereby realizing the riveting of the electrode terminal 22 to the wall portion 211. The protrusion 222 protrudes from the end of the terminal body 221 facing the main body portion 231 in the thickness direction X of the wall portion, and the protrusion 222 is used for electrical connection with the first electrode tab 232. Of course, in other embodiments, the electrode terminal 22 may also be a structure that is snapped or glued to the wall portion 211.

[0251] Referring to Figures 6 and 9, a sealing member 24 is also provided between the electrode terminal 22 and the wall portion 211. The sealing member 24 is configured to seal the gap between the electrode terminal 22 and the wall portion 211. The sealing member 24 includes a first sealing portion 241, a second sealing portion 242, and a third sealing portion 243 connected in sequence. The first sealing portion 241 is located between the first limiting portion 2211 and the wall portion 211. The second sealing portion 242 is located between the terminal body 221 and the hole wall surface of the mounting hole 2111. The third sealing portion 243 is located between the second limiting portion 2212 and the wall portion 211. This helps to improve the sealing effect of the sealing member 24 on the wall portion 211 and the electrode terminal 22, and also improves the effect of the sealing member 24 on separating the wall portion 211 and the electrode terminal 22. It should be noted that, as shown in Figures 6 and 9, the first sealing portion 241 of the seal 24 is located inside the through hole 2511 of the first insulating portion 251 and extends radially outward from the outer peripheral surface of the first limiting portion 2211 of the cylindrical battery cell 20. Along the radial direction of the cylindrical battery cell 20, a first gap 26 is formed between the first sealing portion 241 of the seal 24 and the hole wall surface of the through hole 2511.

[0252] The sealing element 24 is made of insulating material, and the sealing element 24 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.

[0253] For example, the material of the seal 24 can be various, such as silicone, plastic or rubber.

[0254] It should be noted that the first sealing portion 241 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 241 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, a portion of the first sealing portion 241 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 241 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 241 of the seal member 24.

[0255] In this embodiment of the application, referring to Figures 4, 5 and 6, the cylindrical battery cell 20 may further include a first current collector 27. The first current collector 27 is disposed between the first insulating portion 251 and the first tab 232 in the thickness direction X of the wall portion. The first current collector 27 connects the protrusion 222 of the electrode terminal 22 and the first tab 232 of the electrode assembly 23 to electrically connect the electrode terminal 22 and the electrode assembly 23.

[0256] Optionally, the connection structure between the first electrode tab 232 and the first current collector 27, and between the first current collector 27 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 27, and the first current collector 27 is welded to the electrode terminal 22, for example, by laser welding or ultrasonic welding.

[0257] 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 27, so that the electrode terminal 22 serves as one output terminal 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 terminal 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 terminals of the cylindrical battery cell 20.

[0258] 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.

[0259] In some embodiments, as shown in Figures 4 and 5, the cylindrical battery cell 20 may further include a second current collector 28, which is 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 28 connects the second tab 233 and the housing 21 to electrically connect the electrode assembly 23 and the housing 21.

[0260] The housing 212 has a protrusion 2123a on its side wall 2123. The second current collector 28 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.

[0261] Optionally, the connection structure between the second current collector 28 and the second tab 233, and between the second current collector 28 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 28, and the second current collector 28 is welded to the housing 21, for example, by laser welding or ultrasonic welding.

[0262] For example, the material of the second current collector 28 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0263] 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.

[0264] In this embodiment, the first insulating member 25 serves to insulate and isolate the first tab 232 and the wall portion 211. In the embodiment where the cylindrical battery cell 20 further includes a first current collector 27 and the first current collector 27 is located between the first insulating portion 251 and the first tab 232 of the first insulating member 25, the first insulating member 25 can also insulate and isolate the first current collector 27 and the wall portion 211.

[0265] The first insulating portion 251 is the part of the first insulating member 25 located between the wall portion 211 and the first tab 232 in the thickness direction X of the wall portion.

[0266] The first insulating part 251 is provided with a through hole 2511. The through hole 2511 is a structure that penetrates the surface of both sides of the first insulating part 251 along the thickness direction X of the wall. The electrode terminal 22 is partially disposed in the through hole 2511 so that the electrode terminal 22 can be connected to the first current collector 27.

[0267] For example, the material of the first insulating member 25 can be various, such as rubber, plastic or silicone.

[0268] Referring to Figures 6, 8, and 9, the first sealing portion 241 of the seal 24 is located between the first limiting portion 2211 and the wall portion 211 of the electrode terminal 22 and is located within the through hole 2511. The first sealing portion 241 of the seal 24 extends beyond the outer peripheral surface of the first limiting portion 2211 in the radial direction of the cylindrical battery cell 20, so that the first gap 26 is formed in the radial direction of the cylindrical battery cell 20 between the first sealing portion 241 of the seal 24 and the hole wall surface of the through hole 2511, so that the first gap 26 is an annular structure extending circumferentially along the through hole 2511.

[0269] The wall portion 211 has an exposed area 2112 that corresponds to the first gap 26 in the thickness direction X of the wall portion. In other words, the portion of the wall portion 211 projected into the first gap 26 in the thickness direction X of the wall portion is the exposed area 2112 of the wall portion 211.

[0270] The first surface 2322 of the first electrode tab 232 is a surface of the first electrode tab 232 facing the wall portion 211 in the thickness direction X of the wall portion. The first surface 2322 is provided with a relief portion 2321 that is recessed in the direction away from the wall portion 211. That is, the relief portion 2321 is a structure provided on the first electrode tab 232 and recessed from the first surface 2322 in the direction away from the wall portion 211. Optionally, the structure of the relief portion 2321 provided on the first surface 2322 can be various. For example, the relief portion 2321 can be a groove structure provided on the first surface 2322 or a hole structure provided on the first surface 2322 and extending along the thickness direction X of the wall portion.

[0271] The projection of the exposed area 2112 in the thickness direction X of the wall is located within the clearance portion 2321. That is, the exposed area 2112 and the clearance portion 2321 are structures that are correspondingly provided in the thickness direction X of the wall, and in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projection of the exposed area 2112 is located within the area defined by the orthographic projection of the clearance portion 2321.

[0272] 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.

[0273] 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.

[0274] In this embodiment, the seal 24 includes a first sealing portion 241 disposed between the first limiting portion 2211 and the wall portion 211 of the electrode terminal 22, so that the seal 24 can seal the gap between the electrode terminal 22 and the wall portion 211 to alleviate the risk of leakage from the mounting hole 2111 of the cylindrical battery cell 20 during use. The first sealing portion 241 of the seal 24 is configured to be accommodated within the through hole 2511 and extend beyond the first limiting portion 2211 in the radial direction away from the central axis of the cylindrical battery cell 20, so that a first gap 26 is formed between the first sealing portion 241 and the hole wall surface of the through hole 2511. This facilitates the placement of the first sealing portion 241 of the seal 24 within the through hole 2511, which helps to reduce the leakage between the first sealing portion 241 of the seal 24 and the first insulating member 25. Assembly interference between insulating parts 251, wherein the first electrode 232 facing the wall 211 has a recessed avoidance part 2321 in the direction away from the wall 211. By setting the exposed area 2112 of the wall 211 corresponding to the first gap 26 to a structure in which the projection of the wall in the thickness direction X is located in the avoidance part 2321, the first electrode 232 can avoid the first gap 26 through the avoidance part 2321. This can effectively alleviate the phenomenon of short circuit between the first electrode 232 and the wall 211 after the first electrode 232 is inserted into the first gap 26, and can also effectively alleviate the phenomenon of electrical breakdown between the first electrode 232 and the wall 211 at the first gap 26. This helps to reduce the risk of internal short circuit during use of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20.

[0275] According to some embodiments of this application, referring to FIG6 and further referring to FIG10, FIG10 is a partial cross-sectional view of the electrode assembly 23 provided in some embodiments of this application. In the projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the exposed area 2112 does not overlap with the orthographic projection of the first electrode tab 232. That is, the projections of the exposed area 2112 of the wall portion 211 and the first electrode tab 232 in the thickness direction X of the wall portion do not overlap. For example, in an embodiment where the electrode assembly 23 is provided with a central through hole 234, the central through hole 234 penetrates both ends of the electrode assembly 23 along the thickness direction X of the wall portion, and the clearance portion 2321 is a part of the central through hole 234, in the projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the exposed area 2112 can be a structure located inside the orthographic projection of the hole wall surface of the central through hole 234, so as to achieve that the projections of the exposed area 2112 of the wall portion 211 and the first electrode tab 232 in the thickness direction X of the wall portion do not overlap.

[0276] In this embodiment, by setting the exposed area 2112 of the wall portion 211 corresponding to the first gap 26 to a structure in which the projection of the wall portion 211 in the thickness direction X and the projection of the first tab 232 in the thickness direction X of the wall portion do not overlap, the projection of the first tab 232 in the thickness direction X of the wall portion does not fall into the first gap 26. This can further alleviate the phenomenon of short circuit between the first tab 232 and the wall portion 211 after the first tab 232 is inserted into the first gap 26, and can further alleviate the phenomenon of electrical breakdown between the first tab 232 and the wall portion 211 at the first gap 26. In this way, the risk of internal short circuit in the cylindrical battery cell 20 during use can be further reduced, thereby further improving the reliability of the cylindrical battery cell 20.

[0277] According to some embodiments of this application, referring to Figures 6 and 10, the electrode assembly 23 has a central through hole 234, which penetrates both ends of the electrode assembly 23 along the thickness direction X of the wall, and the clearance portion 2321 is a part of the central through hole 234.

[0278] The central through hole 234 is an internal channel for gas flow in the cylindrical battery cell 20 of the electrode assembly 23. 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.

[0279] The clearance portion 2321 is part of the central through hole 234. That is, at least part of the central through hole 234 that penetrates the first electrode tab 232 is the clearance portion 2321 of the first electrode tab 232 used to avoid the exposed area 2112 of the wall portion 211.

[0280] 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 portion. By setting a portion of the central through hole 234 as a clearance portion 2321 for avoiding the exposed area 2112 of the wall portion 211, the clearance portion 2321 can not only avoid the exposed area 2112 of the wall portion 211, 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.

[0281] In some embodiments, as shown in FIG10, 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 2321, and the diameter of the first hole segment 2341 is smaller than the diameter of the second hole segment 2342.

[0282] Wherein, the diameter of the first hole segment 2341 is smaller than the diameter of the second hole segment 2342. That is to say, the projection of the first hole segment 2341 on the thickness direction X of the wall is located inside the second hole segment 2342. 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 is located inside the orthographic projection of the hole wall surface of the second hole segment 2342.

[0283] For example, in Figure 10, 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. If the first electrode tab 232 is a positive electrode tab, and in an embodiment where a positive transition region is provided in the positive electrode blank area of ​​the positive electrode sheet, then 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. If the first electrode tab 232 In embodiments where a negative electrode tab is provided and a negative electrode 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 embodiments where the separator of the main body 231 extends along the thickness direction X of the wall to the first electrode tab 232, the first hole segment 2341 can also be partially located within the first electrode tab 232. Correspondingly, the second hole segment 2342 has an overall pore diameter larger than that 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. It should be noted that in embodiments where the hole wall surface of the second hole segment 2342 forms an inclined first circumferential surface 2321b, the second hole segment 2342 comprises two interconnected hole segments, one of which is a hole structure of equal diameter, and the other of which has a gradually increasing pore diameter.

[0284] In this embodiment, by setting the second hole segment 2342 located within the first electrode tab 232 as a clearance portion 2321, and setting the diameter of the first hole segment 2341 to be smaller than the diameter of the second hole segment 2342, the effect of the second hole segment 2342 as a clearance portion 2321 in avoiding the exposed area 2112 of the wall portion 211 can be improved, while also alleviating the phenomenon that the first hole segment 2341 located within the main body portion 231 occupies too much space, thereby helping to improve the energy density of the electrode assembly 23.

[0285] 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 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 231, and the second hole segment 2342 is located within the first electrode tab 232. The second hole segment 2342 is a clearance portion 2321, and the diameter of the first hole segment 2341 is equal to the diameter of the second hole segment 2342. That is, in the projection plane perpendicular to the thickness direction X of the wall portion, 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.

[0286] 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 2321 to avoid the exposed area 2112 of the wall part 211, thereby reducing the manufacturing difficulty of the electrode assembly 23.

[0287] In some embodiments, referring to FIG6, the electrode terminal 22 includes a terminal body 221 disposed within a mounting hole 2111, and the terminal body 221 is connected to the wall portion 211. The terminal body 221 includes a first limiting portion 2211. The terminal body 221 extends along the thickness direction X of the wall portion into the through hole 2511, and the seal 24 further includes a second sealing portion 242, which is located between the terminal body 221 and the hole wall surface of the mounting hole 2111 to seal the gap between the terminal body 221 and the hole wall surface of the mounting hole 2111.

[0288] As shown in Figures 6 and 9, the seal 24 includes a first sealing portion 241, a second sealing portion 242, and a third sealing portion 243 connected in sequence. The first sealing portion 241 is located between the first limiting portion 2211 and the wall portion 211. The second sealing portion 242 is located between the terminal body 221 and the wall surface of the mounting hole 2111. The third sealing portion 243 is located between the second limiting portion 2212 and the wall portion 211. In other words, the portion of the seal 24 located radially between the terminal body 221 and the wall surface of the through hole 2511 in the cylindrical battery cell 20 is the second sealing portion 242 of the seal 24. The second sealing portion 242 is configured to seal the gap between the terminal body 221 and the wall surface of the mounting hole 2111. Furthermore, the first sealing portion 241 and the second sealing portion 242 of the seal 24 can further enhance the sealing effect of the seal 24 on the wall portion 211 and the electrode terminal 22, and can also enhance the insulating effect of the seal 24 on the wall portion 211 and the electrode terminal 22.

[0289] In this embodiment, by placing the terminal body 221 of the electrode terminal 22 inside the mounting hole 2111 of the wall portion 211, and setting the second sealing portion 242 of the seal 24 between the terminal body 221 and the hole wall surface of the mounting hole 2111, the seal 24 can seal the gap between the terminal body 221 and the hole wall surface of the mounting hole 2111, thereby further improving the sealing effect of the seal 24 on the wall portion 211 and the electrode terminal 22, and improving the stability and reliability of the seal 24 installed between the wall portion 211 and the electrode terminal 22, which helps to reduce the risk of the seal 24 falling off during use.

[0290] In some embodiments, as shown in Figures 6, 8, and 9, the terminal body 221 further includes a second limiting portion 2212 located on the side of the wall portion 211 facing away from the interior of the housing 21. 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. The seal 24 further includes a third sealing portion 243 located between the wall portion 211 and the second limiting portion 2212 along the thickness direction X of the wall portion to seal the gap between the wall portion 211 and the second limiting portion 2212.

[0291] 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.

[0292] 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. In addition, the seal 24 is also provided with a third sealing part 243 located between the second limiting part 2212 and the wall part 211, so that the seal 24 can also seal the gap between the second limiting part 2212 and the wall part 211, which is conducive to further improving the sealing effect of the seal 24 on the wall part 211 and the electrode terminal 22, and can improve the stability and reliability of the seal 24 installed between the wall part 211 and the electrode terminal 22, which is conducive to reducing the risk of the seal 24 falling off during use.

[0293] According to some embodiments of this application, referring to Figures 11 and 12, Figure 11 is a cross-sectional view of a cylindrical battery cell 20 provided in some embodiments of this application, and Figure 12 is a partial enlarged view of point B of the cylindrical battery cell 20 shown in Figure 11. The cylindrical battery cell 20 may further include a second insulating member 29, which is located between the wall portion 211 and the first tab 232 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 26.

[0294] The second insulating member 29 serves to block the first gap 26 between the first sealing part 241 and the hole wall surface of the through hole 2511 between the wall part 211 and the first electrode 232. The projection of the second insulating member 29 in the thickness direction X of the wall part covers the first gap 26. That is, the entire projection of the first gap 26 in the thickness direction X of the wall part is located inside the second insulating member 29.

[0295] The second insulating member 29 is located between the wall portion 211 and the first electrode tab 232 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 251, or a structure disposed between the first insulating portion 251 and the first electrode tab 232, or a structure disposed within the through hole 2511.

[0296] For example, the second insulating member 29 is made of an insulating material, and the material of the second insulating member 29 can be various, such as rubber, plastic or silicone.

[0297] In this embodiment, by providing a second insulating member 29 between the wall portion 211 and the first electrode tab 232, and the projection of the second insulating member 29 in the thickness direction X of the wall portion covers the first gap 26 between the first sealing portion 241 and the first insulating portion 251, the second insulating member 29 can shield the first gap 26, thereby increasing the creepage distance between the wall portion 211 and the first electrode tab 232 at the first gap 26. Furthermore, the second insulating member 29 can provide a certain barrier between the first electrode tab 232 and the wall portion 211, further mitigating the phenomenon of the first electrode tab 232 overlapping with the wall portion 211 when inserted into the first gap 26 or of electrical breakdown occurring between the first electrode tab 232 and the wall portion 211 at the first gap 26. This helps to further reduce the risk of internal short circuits in the cylindrical battery cell 20 during use, thereby further improving the reliability of the cylindrical battery cell 20.

[0298] According to some embodiments of this application, as shown in FIG12, the second insulating member 29 protrudes from the wall surface of the through hole 2511.

[0299] The second insulating member 29 protrudes from the wall of the through hole 2511. That is, the second insulating member 29 is located inside the through hole 2511 and connected to the wall of the through hole 2511. Optionally, the second insulating member 29 can be integrally formed with the first insulating part 251 or it can be a separate structure. For example, the second insulating member 29 can be connected to the wall of the through hole 2511 by adhesive or snap-fit.

[0300] In this embodiment, by configuring the second insulating member 29 as a structure protruding from the hole wall of the through hole 2511 of the first insulating part 251, the second insulating member 29 is connected to the hole wall of the through hole 2511 of the first insulating part 251. This allows the second insulating member 29 to share a portion of the space with the first insulating part 251 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 251 or the first tab 232 and the first insulating part 251 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.

[0301] In some embodiments, please continue to refer to Figure 12, the second insulating member 29 and the first insulating portion 251 are integrally formed. That is, the second insulating member 29 and the first insulating portion 251 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 structure protruding from the wall surface of the through hole 2511, and the second insulating member 29 is an annular structure extending circumferentially along the through hole 2511.

[0302] In this embodiment, by setting the second insulating member 29 and the first insulating portion 251 of the first insulating member 25 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 2511 of the first insulating portion 251 can be improved, which helps to reduce the risk of the second insulating member 29 falling off the first insulating portion 251 during use, thereby improving the reliability of the second insulating member 29 blocking the first gap 26. On the other hand, it can reduce the difficulty of setting the second insulating member 29 on the hole wall of the through hole 2511 of the first insulating portion 251, which helps to reduce the manufacturing difficulty of the cylindrical battery cell 20.

[0303] According to some embodiments of this application, referring to Figures 13 and 14, Figure 13 is a cross-sectional view of a cylindrical battery cell 20 provided in some embodiments of this application, and Figure 14 is a partial enlarged view of point C of the cylindrical battery cell 20 shown in Figure 13. The cylindrical battery cell 20 may further include a first current collector 27 disposed between a first insulating portion 251 and a first tab 232, connecting an electrode terminal 22 and a first tab 232 to electrically connect the electrode terminal 22 and the first tab 232. Along the thickness direction X of the wall portion, a second insulating member 29 is disposed between the first insulating portion 251 and the first current collector 27.

[0304] Along the thickness direction X of the wall portion, the second insulating member 29 is disposed between the first insulating portion 251 and the first current collector 27. That is, the second insulating member 29 is located on the side of the first insulating portion 251 facing the first current collector 27 in the thickness direction X of the wall portion.

[0305] In this embodiment, by placing the second insulating member 29 between the first insulating portion 251 and the first current collector 27, 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.

[0306] In some embodiments, as shown in FIG14, the second insulating member 29 is connected to the surface of the first current collector 27 facing the first insulating portion 251.

[0307] For example, the second insulating member 29 is bonded to the surface of the first current collector 27 facing the wall portion 211. The second insulating member 29 may be an insulating tape, insulating paper, or insulating film bonded to the first current collector 27.

[0308] In this embodiment, by setting the second insulating member 29 to be connected to the surface of the first current collector 27 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 251 and the first current collector 27 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 27 and then assemble it together with the first current collector 27 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.

[0309] 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 251 facing the first current collector 27.

[0310] For example, the second insulating member 29 may be a structure that is bonded to the surface of the first insulating part 251 facing the first current collector 27, and the second insulating member 29 may be an insulating tape, insulating paper or insulating film, etc., bonded to the first insulating part 251.

[0311] In this embodiment, by configuring the second insulating member 29 as a structure connected to the surface of the first insulating part 251 facing the first current collector 27, on the one hand, the stability and reliability of the second insulating member 29 disposed between the first insulating part 251 and the first current collector 27 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 251 first and the first gap 26 can be blocked before the first current collector 27 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 26.

[0312] In some embodiments, referring to FIG14, the first current collector 27 includes a terminal connection area 272 connected to the electrode terminal 22. In a projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the terminal connection area 272 does not overlap with the orthographic projection of the second insulating member 29. That is, in a structure where the second insulating member 29 is located between the first current collector 27 and the first insulating portion 251, the projections of the terminal connection area 272 and the second insulating member 29 in the thickness direction X of the wall portion do not overlap.

[0313] In this embodiment, by setting the first current collector 27 for interconnecting with the terminal connection area 272 of the electrode terminal 22 to a structure in which the projection of the first current collector 27 in the thickness direction X of the wall and the projection of the second insulating member 29 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 272 can be reduced, which is beneficial to reducing the connection difficulty between the terminal connection area 272 and the electrode terminal 22, and can improve the assembly quality between the terminal connection area 272 and the electrode terminal 22.

[0314] According to some embodiments of this application, as shown in FIG14, the terminal connection area 272 is welded to the electrode terminal 22 to form a connection portion 30. The connection portion 30 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.

[0315] The connection portion 30 formed by welding the terminal connection area 272 and the electrode terminal 22 is a solder mark formed by welding the terminal connection area 272 and the electrode terminal 22 together.

[0316] The connecting portion 30 and the second insulating member 29 are spaced apart in the radial direction of 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 30 and the orthographic projection of the second insulating member 29 are spaced apart in the radial direction of the cylindrical battery cell 20, and the spacing between the orthographic projection of the connecting portion 30 and the orthographic projection of the second insulating member 29 in the radial direction of the cylindrical battery cell 20 is greater than or equal to 5 mm.

[0317] For example, the radial spacing between the connecting portion 30 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.

[0318] In this embodiment, by setting the second insulating member 29 and the connecting portion 30 to be arranged radially spaced at a distance greater than or equal to 5 mm in the cylindrical battery cell 20, the radial separation distance between the second insulating member 29 and the connecting portion 30 in the cylindrical battery cell 20 can be increased. This reduces the risk of high-temperature damage to the second insulating member 29 by the connecting portion 30 during the welding connection of the terminal connection area 272 and the electrode terminal 22 to form the connecting portion 30. 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.

[0319] 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 251 and the wall portion 211. That is, the second insulating member 29 is located on the side of the first insulating portion 251 facing the wall portion 211 in the thickness direction X of the wall portion.

[0320] In this embodiment, by placing the second insulating member 29 between the first insulating portion 251 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 272, thereby reducing the connection difficulty between the terminal connection area 272 and the electrode terminal 22.

[0321] Optionally, the second insulating member 29 is connected to the surface of the wall portion 211 facing the first insulating portion 251.

[0322] For example, the second insulating member 29 is adhered to the surface of the wall portion 211 facing the first insulating portion 251. The second insulating member 29 may be an 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 or the like, coated on the surface of the wall portion 211 facing the first insulating portion 251.

[0323] 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 251, it is beneficial to improve the stability and reliability of the second insulating member 29 disposed between the first insulating portion 251 and the wall portion 211, so as to reduce the phenomenon of the second insulating member 29 shifting or displacing during use.

[0324] Optionally, in this embodiment, the orthographic projection of the second insulating member 29 in the projection plane perpendicular to the thickness direction X of the wall portion can also overlap with the orthographic projection of the first sealing portion 241. That is, a portion of the second insulating member 29 is located between the sealing member 24 and the wall portion 211 in the thickness direction X of the wall portion, such that the wall portion 211 and the first sealing portion 241 are structured to clamp a portion of the second insulating member 29.

[0325] In this embodiment, by setting the projections of the second insulating member 29 and the first sealing part 241 in the thickness direction X of the wall to an overlapping structure, a portion of the second insulating member 29 is located between the first sealing part 241 and the wall part 211 of the sealing member 24 in the thickness direction X of the wall. This can further improve the stability and reliability of the second insulating member 29 disposed between the wall part 211 and the first insulating part 251, 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 26, thereby further reducing the risk of short circuit or electrical breakdown between the wall part 211 and the first electrode 232 at the first gap 26.

[0326] According to some embodiments of this application, as shown in Figures 13 and 14, 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 251. That is, in the thickness direction X of the wall portion, portions of the second insulating member 29 and the first insulating portion 251 are stacked on top of each other. Correspondingly, the second insulating member 29 can be a structure disposed between the wall portion 211 and the first insulating portion 251 in the thickness direction X of the wall portion, or it can be a structure disposed between the first tab 232 and the first insulating portion 251 in the thickness direction X of the wall portion.

[0327] In this embodiment, by setting the projection of the second insulating member 29 on the thickness direction X of the wall portion to partially overlap with the first insulating portion 251, the second insulating member 29 is stacked on one side of the first insulating portion 251 on the thickness direction X of the wall portion, so that the second insulating member 29 and the first insulating portion 251 have overlapping areas, thereby improving the shielding effect of the second insulating member 29 on the first gap 26, and further reducing the risk of short circuit or electrical breakdown of the wall portion 211 and the first electrode 232 at the first gap 26.

[0328] According to some embodiments of this application, referring to Figures 4, 5 and 6, the cylindrical battery cell 20 may further include a first current collector 27. The first current collector 27 is disposed between the first insulating portion 251 and the first tab 232 along the thickness direction X of the wall portion, and the first current collector 27 connects the electrode terminal 22 and the first tab 232 to electrically connect the first tab 232 and the electrode terminal 22.

[0329] The first current collector 27 serves to electrically connect the electrode terminal 22 and the electrode assembly 23. The material of the first current collector 27 can be various, such as copper, iron, aluminum, steel or aluminum alloy.

[0330] In this embodiment, by providing a first current collector 27 between the first insulating portion 251 and the first tab 232 of the first insulating member 25, and by connecting the electrode terminal 22 and the first tab 232, the first current collector 27 can achieve insulation isolation between the first current collector 27 and the wall portion 211 through the first insulating member 25, while also reducing the difficulty of electrical connection between the first tab 232 and the electrode terminal 22, thereby reducing the assembly difficulty of the cylindrical battery cell 20.

[0331] According to some embodiments of this application, referring to Figures 4, 5, and 6, and further referring to Figures 15 and 16, Figure 15 is a structural schematic diagram of the first current collecting member 27 provided in some embodiments of this application, and Figure 16 is a front view of the first current collecting member 27 provided in some embodiments of this application in the thickness direction X of the wall portion. In some embodiments, the first current collecting member 27 forms a hollow area 276, and along the thickness direction X of the wall portion, the portion of the projection of the exposed area 2112 is located within the hollow area 276.

[0332] The first current collector 27 comprises a current collector body, a terminal connection area 272, an elastic area 273, an electrode connection area 274, and a base area 275. The current collector body is disposed between the first electrode 232 and the first insulating portion 251 in the thickness direction X of its wall. The terminal connection area 272 is connected to the electrode terminal 22, and is sequentially connected to the current collector body area 271 through the elastic area 273 and the base area 275. The electrode connection area 274 is connected to the current collector body area 271 and is connected to the first electrode 232. Region 271 is an annular structure surrounding the terminal connection region 272, so that the current collection body region 271 is enclosed to form an inner peripheral hole. As shown in Figures 15 and 16, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projections of the terminal connection region 272, the tab connection region 274, the elastic region 273 and the base region 275 of the first current collection member 27 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 region 272, the tab connection region 274, the elastic region 273 and the base region 275 is the hollow region 276 of the first current collection member 27.

[0333] Along the thickness direction X of the wall portion, the projection of the exposed area 2112 is located within the hollow area 276. That is, the projection of the exposed area 2112 corresponding to the wall portion 211 and the first gap 26 is located within the hollow area 276 of the first current collecting member 27. For example, referring to FIG6, in this embodiment of the 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 273, while the other portions are all located within the hollow area 276 of the first current collecting member 27.

[0334] In this embodiment, by forming a hollow area 276 on the first current collector 27, and setting the exposed area 2112 of the wall portion 211 corresponding to the first gap 26 to be located within the hollow area 276 in the thickness direction X of the wall portion, it is beneficial to reduce the area of ​​the first current collector 27 in the thickness direction X of the wall portion corresponding to the first gap 26, thereby reducing the risk of short circuit or electrical breakdown between the wall portion 211 and the first current collector 27 at the first gap 26.

[0335] According to some embodiments of this application, referring to Figures 6, 15, and 16, the first current collector 27 may include a current collector body region 271, a terminal connection region 272, and an elastic region 273. At least a portion of the current collector body region 271 is disposed between the first insulating portion 251 and the first electrode tab 232 in the thickness direction X of the wall, and the current collector body region 271 is electrically connected to the first electrode tab 232. The terminal connection region 272 is connected to the electrode terminal 22. The elastic region 273 connects the current collector body region 271 and the terminal connection region 272, and the elastic region 273 is configured to deform when the terminal connection region 272 and the current collector body region 271 move closer or further apart along the thickness direction X of the wall.

[0336] At least a portion of the current collecting main body region 271 is disposed between the first insulating portion 251 and the first electrode 232 in the thickness direction X of the wall portion, and the current collecting main body region 271 is electrically connected to the first electrode 232. That is, the first current collecting member 27 has a current collecting main body region 271 located between the first insulating portion 251 and the first electrode 232 in the thickness direction X of the wall portion, and the current collecting main body region 271 serves to be electrically connected to the first electrode 232.

[0337] It should be noted that the current collector body region 271 can be a structure directly connected to the first electrode 232 or an indirectly connected structure. For example, referring to Figure 15, the first current collector component 27 may further include an electrode connection region 274, which is connected to the current collector body region 271 and connected to the first electrode 232 to electrically connect the first electrode 232 and the current collector body region 271. For example, the electrode connection region 274 is welded to the first electrode 232.

[0338] The terminal connection area 272 is connected to the electrode terminal 22. That is, the first current collector 27 has a structure in which the terminal connection area 272 and the electrode terminal 22 are connected to each other, such as by welding or bonding.

[0339] For example, the terminal connection area 272 is connected to the end face of the electrode terminal 22 on the thickness direction X of the wall portion near the end of the main body portion 231.

[0340] The elastic region 273 connects the current collection body region 271 and the terminal connection region 272, that is, the current collection body region 271 and the terminal connection region 272 of the first current collection member 27 are interconnected through the elastic region 273.

[0341] Along the thickness direction X of the wall, the elastic region 273 is configured to deform when the terminal connection region 272 and the wall 211 move closer or further apart. That is, when the first current collector 27 is compressed or stretched in the thickness direction X of the wall, the elastic region 273 can deform when the current collector body region 271 and the terminal connection region 272 move closer or further apart. It should be noted that the elastic region 273 can undergo elastic deformation or plastic deformation when it deforms.

[0342] Optionally, the number of elastic regions 273 connected between the current collection body area 271 and the terminal connection area 272 can be one or more.

[0343] In this embodiment, the first current collector 27 is provided with a current collector body area 271, an elastic area 273, and a terminal connection area 272. The elastic area 273 is connected between the current collector body area 271 and the terminal connection area 272. The current collector body area 271 is electrically connected to the first electrode tab 232, and the terminal connection area 272 is connected to the electrode terminal 22 to realize the electrical connection between the electrode terminal 22 and the electrode assembly 23. The elastic area 273 is designed to be deformable, allowing it to deform when the terminal connection area 272 and the current collector body area 271 move closer or further apart along the thickness direction X of the wall. This deformability allows the terminal connection area 272 to move along the thickness direction X of the wall when subjected to pressure or other phenomena. It can absorb the assembly error between the electrode terminal 22 and the terminal connection area 272, which is beneficial to improve the assembly quality between the electrode terminal 22 and the terminal connection area 272. On the other hand, the elastic area 273 can play a certain buffering role between the current collector body area and the terminal connection area 272. Thus, when the electrode assembly 23 shakes or shifts, it can alleviate the rigid tension between the current collector body area and the terminal connection area 272, between the terminal connection area 272 and the electrode terminal 22, and between the current collector body area and the first tab 232. This helps to reduce the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23, and also helps to reduce the phenomenon of the first current collector 27 being damaged by tension. In this way, it can effectively improve the stability and service life of the cylindrical battery cell 20.

[0344] According to some embodiments of this application, as shown in Figures 6, 15, and 16, in a projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the terminal connection area 272 and the orthographic projection of the current collection body area 271 do not overlap. That is, the projection of the terminal connection area 272 in the thickness direction X of the wall portion does not fall into the current collection body area 271.

[0345] For example, the current collector area 271 is an annular structure surrounding the terminal connection area 272, and the terminal connection area 272 is spaced apart from the current collector area 271 in the radial direction of the cylindrical battery cell 20, so that the projections of the terminal connection area 272 and the current collector area 271 in the thickness direction X of the wall do not overlap. Correspondingly, the elastic area 273 connects the terminal connection area 272 and the current collector area 271. 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.

[0346] In this embodiment, by setting the terminal connection area 272 and the current collector body area 271 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 271 on the terminal connection area 272 can be reduced when the terminal connection area 272 is close to or far away from the current collector body area 271 in the thickness direction X of the wall. This is beneficial to expanding the range of movement of the terminal connection area 272 relative to the current collector body area 271 in the thickness direction X of the wall. This can further improve the deformation degree of the elastic area 273 in the thickness direction X of the wall, thereby further improving the effect of the elastic area 273 in absorbing the assembly error between the electrode terminal 22 and the terminal connection area 272, so as to further improve the assembly quality between the electrode terminal 22 and the terminal connection area 272, and further improve the buffering effect of the elastic area 273 between the current collector body area and the terminal connection area 272, so as to further reduce the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23.

[0347] According to some embodiments of this application, referring to Figures 15 and 16, in a projection plane perpendicular to the thickness direction X of the wall, the orthographic projection of the elastic region 273 and the orthographic projection of the current collection body region 271 do not overlap. That is, the projection of the elastic region 273 in the thickness direction X of the wall does not fall into the current collection body region 271.

[0348] For example, the current collector body area 271 is an annular structure surrounding the terminal connection area 272. The terminal connection area 272 is spaced apart from the current collector body area 271 in the radial direction of the cylindrical battery cell 20. The elastic area 273 is connected at both ends in its extension direction to the outer peripheral surface of the terminal connection area 272 and the inner peripheral surface of the current collector body area 271, respectively, so as to realize that the projections of the elastic area 273 and the current collector body area 271 in the thickness direction X of the wall do not overlap.

[0349] It should be noted that the elastic region 273 and the main flow collection region 271 can be directly connected, that is, one end of the elastic region 273 in its extension direction is directly connected to the inner circumferential surface of the main flow collection region 271. Of course, the elastic region 273 and the main flow collection region 271 can be indirectly connected. For example, in Figure 15, the first flow collection component 27 can also include a base region 275, and the elastic region 273 is a structure that is connected to the inner circumferential surface of the main flow collection region 271 through the base region 275.

[0350] In this embodiment, by setting the elastic region 273 and the current collector body region 271 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 271 on the elastic region 273 can be reduced when the terminal connection region 272 and the current collector body region 271 move closer or further away from each other along the thickness direction X of the wall, causing the elastic region 273 to deform. This allows the elastic region 273 to deform better during assembly or use, which is beneficial to expanding the degree of deformation of the elastic region 273 in the thickness direction X of the wall. This further enhances the effect of the elastic region 273 in absorbing assembly errors between the electrode terminal 22 and the terminal connection region 272, thereby further improving the assembly quality between the electrode terminal 22 and the terminal connection region 272. It also further enhances the buffering effect of the elastic region 273 between the current collector body region and the terminal connection region 272, thereby further reducing the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23.

[0351] According to some embodiments of this application, please refer to Figures 6, 15 and 16. The electrode terminal 22 and the terminal connection area 272 are arranged along the thickness direction X of the wall. Along the thickness direction X of the wall, the terminal connection area 272 has a second surface 2721 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 and the second surface 2721 are welded together.

[0352] The second surface 2721 is the surface of the terminal connection area 272 facing the electrode terminal 22 in the thickness direction X of the wall portion, and is also the surface on which the terminal connection area 272 and the electrode terminal 22 are connected to each other. Similarly, the connection surface 223 is the end face of the electrode terminal 22 in the thickness direction X of the wall portion near the end of the main body portion 231.

[0353] The electrode terminal 22 and the terminal connection area 272 are arranged and connected along the thickness direction X of the wall portion, and the connection surface 223 and the second surface 2721 are welded together, such that the end of the electrode terminal 22 near the main body portion 231 in the thickness direction X of the wall portion is welded to the side of the terminal connection area 272 away from the main body portion 231, wherein the connection surface 223 and the second surface 2721 are welded together to form the connection portion 30.

[0354] Optionally, the connecting surface 223 of the electrode terminal 22 and the second surface 2721 of the terminal connection area 272 are parallel and fit together, and both the connecting surface 223 of the electrode terminal 22 and the second surface 2721 of the terminal connection area 272 are perpendicular to the thickness direction X of the wall.

[0355] In this embodiment, by arranging the electrode terminal 22 and the terminal connection area 272 along the thickness direction X of the wall, and welding the second surface 2721 of the terminal connection area 272 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 272 can be reduced, and the connection stability and overcurrent stability between the terminal connection area 272 and the electrode terminal 22 can be improved. On the other hand, under the action of the elastic area 273, the assembly error between the electrode terminal 22 and the terminal connection area 272 can be absorbed, thereby alleviating the welding gap between the terminal connection area 272 and the electrode terminal 22, which helps to reduce the risk of poor welding between the terminal connection area 272 and the electrode terminal 22, and improves the welding quality between the terminal connection area 272 and the electrode terminal 22.

[0356] According to some embodiments of this application, referring to Figures 6 and 15, along the thickness direction X of the wall portion, the first insulating portion 251 has a third surface 2512 facing the first electrode tab 232, and the third surface 2512 is further away from the main body portion 231 than the connecting surface 223. That is, 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 251 facing the main body portion 231.

[0357] In this embodiment, by setting the third surface 2512 of the first insulating portion 251 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 272 are connected, on the one hand, the obstruction and interference of the first insulating portion 251 on the electrode terminal 22 can be reduced, so that the connecting surface 223 of the electrode terminal 22 can be welded to the second surface 2721 of the terminal connection area 272. On the other hand, it is easier for the electrode terminal 22 to press the terminal connection area 272 along the thickness direction X of the wall portion, which is beneficial to improving the contact effect between the second surface 2721 and the connecting surface 223, thereby effectively improving the welding quality between the second surface 2721 and the connecting surface 223, and reducing phenomena such as incomplete soldering between the terminal connection area 272 and the electrode terminal 22.

[0358] According to some embodiments of this application, please continue to refer to Figures 6 and 15. Along the thickness direction X of the wall portion, the current collecting main body region 271 has a fourth surface 2711 that is away from the main body portion 231, and the fourth surface 2711 is further away from the main body portion 231 than the second surface 2721. That is, the electrode terminal 22 is a structure in which the terminal connection region 272 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 272 that is 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 271 that is away from the main body portion 231.

[0359] The fourth surface 2711 of the current collecting main body region 271 is the surface of the current collecting main body region 271 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 271 facing the first insulating portion 251 in the thickness direction X of the wall portion. For example, the fourth surface 2711 of the current collecting main body region 271 abuts against the third surface 2512 of the first insulating portion 251.

[0360] In this embodiment, by setting the fourth surface 2711 of the current collector 271 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 second surface 2721 of the terminal connection area 272 connecting the electrode terminal 22, the electrode terminal 22 is structured to press down on the terminal connection area 272 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 second surface 2721 of the terminal connection area 272 and the connection surface 223 of the electrode terminal 22, which is beneficial to further improve the welding quality between the terminal connection area 272 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 fourth surface 2711. This also enables the electrode terminal 22 and the current collector 271 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.

[0361] In some embodiments, referring to Figures 6 and 15, along the thickness direction X of the wall portion, the terminal connection area 272 has a fifth surface 2722 facing the main body portion 231, and the current collection main body area 271 has a sixth surface 2712 facing the main body portion 231, the sixth surface 2712 being further away from the main body portion 231 than the fifth surface 2722.

[0362] In this embodiment, by further configuring the fifth surface 2722 of the terminal connection area 272 facing the main body 231 to be closer to the main body 231 in the thickness direction X of the wall portion than the sixth surface 2712 of the current collecting main body area 271 facing the main body 231, the terminal connection area 272 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 271. This can further improve the effect of the electrode terminal 22 pressing the terminal connection area 272, thereby reducing the assembly gap between the second surface 2721 of the terminal connection area 272 and the connection surface 223 of the electrode terminal 22, which is beneficial to further improve the welding quality between the terminal connection area 272 and the electrode terminal 22.

[0363] In some embodiments, referring to FIG6, at least a portion of the terminal connection area 272 is accommodated within the clearance portion 2321 along the thickness direction X of the wall. That is, at least a portion of the terminal connection area 272 is inserted into the clearance portion 2321 along the thickness direction X of the wall.

[0364] It should be noted that the terminal connection area 272 can be a structure in which the entire wall thickness direction X is located within the clearance portion 2321, or it can be a structure in which it is only partially located within the clearance portion 2321.

[0365] In this embodiment, by setting at least a portion of the terminal connection area 272 to be accommodated within the clearance portion 2321 in the thickness direction X of the wall, the cylindrical battery cell 20 with this structure can achieve the first tab 232 clearance from the terminal connection area 272, while also enabling the terminal connection area 272 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.

[0366] 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 271 has a fourth surface 2711 that is away from the main body 231, and the fourth surface 2711 is closer to the main body 231 than the second surface 2721. That is, the terminal connection region 272 has a structure that is raised in the thickness direction X of the wall relative to the current collector main region 271 towards the wall 211.

[0367] In this embodiment, by setting the fourth surface 2711 of the current collector 271 away from the main body 231 to be closer to the main body 231 in the thickness direction X of the wall than the second surface 2721 of the terminal connection area 272 away from the main body 231, the second surface 2721 of the terminal connection area 272 can be closer to the connection surface 223 of the electrode terminal 22 in the thickness direction X of the wall than the fourth surface 2711 of the current collector 271. This facilitates the connection between the second surface 2721 of the terminal connection area 272 and the electrode terminal 22. The surface 223 is welded together, which can better absorb the assembly error between the electrode terminal 22 and the terminal connection area 272, which is beneficial to improve the assembly quality between the electrode terminal 22 and the terminal connection area 272. On the other hand, it can enable the electrode terminal 22 to press the terminal connection area 272 better in the thickness direction X of the wall towards the main body 231, which is beneficial to reduce the assembly gap between the second surface 2721 of the terminal connection area 272 and the connection surface 223 of the electrode terminal 22, thereby improving the welding quality between the terminal connection area 272 and the electrode terminal 22.

[0368] Optionally, along the thickness direction X of the wall portion, the first insulating portion 251 has a third surface 2512 facing the first electrode tab 232, and the third surface 2512 is closer to the main body portion 231 than the connecting surface 223. That is, in the implementation where the terminal connection area 272 is raised along the thickness direction X of the wall portion towards the wall portion 211 relative to the current collecting main body area 271, the end of the electrode terminal 22 near the main body portion 231 in the thickness direction X of the wall portion does not extend beyond the side of the first insulating portion 251 facing the first electrode tab 232, so that the end of the electrode terminal 22 near the main body portion 231 in the thickness direction X of the wall portion does not extend out of the through hole 2511.

[0369] In this embodiment, the third surface 2512 of the first insulating portion 251 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 electrode terminal 22 having one end in the thickness direction X of the wall portion near the main body 231 located within the through hole 2511 and not extending out of the side of the first insulating portion 251 facing the first tab 232. This reduces the phenomenon of the electrode terminal 22 occupying the space on the side of the first insulating portion 251 facing the first tab 232 and reduces the interference between the electrode terminal 22 and other components.

[0370] In this embodiment, at least a portion of the terminal connection area 272 may be accommodated within the through hole 2511 along the thickness direction X of the wall portion, that is, the terminal connection area 272 may be a structure in which the through hole 2511 of the first insulating portion 251 is inserted along the thickness direction X of the wall portion.

[0371] In this embodiment, by configuring at least a portion of the terminal connection area 272 to be accommodated within the through hole 2511 in the thickness direction X of the wall, the terminal connection area 272 can share a portion of the space with the first insulating portion 251 in the thickness direction X of the wall, which is beneficial to improving the internal space utilization of the cylindrical battery cell 20.

[0372] According to some embodiments of this application, as shown in Figures 5 and 6, 11 and 12, and 13 and 14, at least a portion of the elastic region 273 deforms and bends.

[0373] For example, the elastic region 273 undergoes partial deformation and bending, and the fourth surface 2711 is further away from the main body 231 in the thickness direction X of the wall portion than the second surface 2721. That is, the electrode terminal 22 is structured to press the terminal connection region 272 down along the thickness direction X of the wall portion towards the main body 231, so that the elastic region 273 is structured to deform and bend along the thickness direction X of the wall portion towards the main body 231, so that the second surface 2721 of the terminal connection region 272 is further away from the main body 231 in the thickness direction X of the wall portion than the current collector. The fourth surface 2711 of the main body region 271 is closer to the main body portion 231, resulting in a height difference between the terminal connection region 272 and the current collecting main body region 271 in the thickness direction X of the wall portion. This also causes the electrode terminal 22 and the current collecting main body region 271 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 271 is an annular structure surrounding the terminal connection region 272, an inner peripheral hole is formed on the inner side of the current collecting main body region 271. Correspondingly, a portion of the electrode terminal 22 is accommodated within the inner peripheral hole along the thickness direction X of the wall portion. Of course, in embodiments where the fourth surface 2711 is closer to the main body portion 231 in the thickness direction X of the wall portion than the second surface 2721, the elastic region 273 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.

[0374] In this embodiment, by setting the elastic region 273 to at least partially bent and deformed, the elastic region 273 is in a state of accumulating elastic force after the electrode terminal 22 presses against the terminal connection region 272. This allows the elastic region 273 to press the second surface 2721 of the terminal connection region 272 tightly against 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 second surface 2721 of the terminal connection region 272 and the connection surface 223 of the electrode terminal 22, which is beneficial to further improve the welding quality between the terminal connection region 272 and the electrode terminal 22.

[0375] According to some embodiments of this application, as shown in Figures 6, 10 and 15, the projection of the terminal connection area 272 is located within the clearance portion 2321 along the thickness direction X of the wall portion.

[0376] The exposed area 2112 of the wall portion 211 and the terminal connection area 272 of the first current collector 27 are both projected in the thickness direction X of the wall portion and are located within the clearance portion 2321. In other words, the first electrode 232 is provided with a clearance portion 2321 in the thickness direction X of the wall portion corresponding to the position of the exposed area 2112 of the wall portion 211 and the terminal connection area 272 of the first current collector 27 to avoid the exposed area 2112 of the wall portion 211 and the terminal connection area 272 of the first current collector 27.

[0377] In this embodiment, by providing a clearance portion 2321 on the first electrode tab 232, and setting the projections of the exposed area 2112 of the wall portion 211 and the terminal connection area 272 in the thickness direction X of the wall portion to be located within the clearance portion 2321, the clearance portion 2321 can ensure that the projections of the exposed area 2112 of the wall portion 211 and the first electrode tab 232 in the thickness direction X of the wall portion do not overlap, while also ensuring clearance for the terminal connection area 272 of the first current collector 27. This allows the terminal connection area 272 to be inserted when it is close to or far from the current collector body area 271 in the thickness direction X of the wall portion. Within the clearance portion 2321, on the one hand, the obstruction and interference of the first electrode tab 232 on the terminal connection area 272 can be reduced, which is conducive to expanding the range of movement of the terminal connection area 272 relative to the current collection body area 271 in the thickness direction X of the wall portion. This can further enhance the deformation degree of the elastic area 273 in the thickness direction X of the wall portion. On the other hand, it can alleviate the phenomenon of the terminal connection area 272 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 portion 231.

[0378] According to some embodiments of this application, referring to Figures 6, 10, and 15, at least a portion of the projection of the elastic region 273 is located within the clearance portion 2321 along the thickness direction X of the wall portion. That is, at least a portion of the elastic region 273 is a structure corresponding to the clearance portion 2321 in the thickness direction X of the wall portion.

[0379] Optionally, the elastic zone 273 may be entirely located within the clearance portion 2321, or only a portion of the projection of the wall portion in the thickness direction X may be located within the clearance portion 2321.

[0380] In this embodiment, by setting at least a portion of the projection of the elastic region 273 onto the thickness direction X of the wall portion to be located within the clearance portion 2321, the elastic region 273 is configured such that at least a portion of the clearance portion 2321 of the first electrode 232 corresponds to the clearance portion 2321 of the first electrode 232 on the thickness direction X of the wall portion. This allows the first electrode 232 to avoid at least a portion of the elastic region 273 when the elastic region 273 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 on the elastic region 273, which is beneficial to expanding the deformation range of the elastic region 273. On the other hand, it alleviates the phenomenon of the elastic region 273 pressing down on the first electrode 232 during use or assembly, which is beneficial to 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.

[0381] It should be noted that the structure of the first tab 232 of the electrode assembly 23 having a clearance portion 2321 is not limited to this. In some embodiments, the electrode assembly 23 can also have other structures. For example, please refer to Figures 6 and 15, and further refer to Figure 17, which is a partial cross-sectional view of the electrode assembly 23 provided in some embodiments of this application. Along the thickness direction X of the wall portion, the current collecting body region 271 abuts against the first surface 2322. The clearance portion 2321 has a clearance opening 2321a formed on the first surface 2322. The side wall surface of the clearance portion 2321 includes a first circumferential surface 2321b. Along the thickness direction X of the wall portion, the end of the first circumferential surface 2321b connected to the first surface 2322 forms the clearance opening 2321a. The first circumferential surface 2321b is inclined from the clearance opening 2321a towards the central axis of the cylindrical battery cell 20, and the projection of the end of the first circumferential surface 2321b away from the clearance opening 2321a in the thickness direction X of the wall portion is located within the clearance opening 2321a. 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 273 and the orthographic projection of the first circumferential surface 2321b overlap.

[0382] Among them, the clearance opening 2321a is an open structure formed on the first surface 2322 by the clearance part 2321 penetrating through the first surface 2322. Along the thickness direction X of the wall, the end of the first peripheral surface 2321b connected to the first surface 2322 forms the clearance opening 2321a. That is to say, the end of the first peripheral surface 2321b near the wall part 211 in the thickness direction X of the wall extends to the first surface 2322 and forms the clearance opening 2321a.

[0383] The first circumferential surface 2321b is inclined from the clearance opening 2321a toward the central axis of the cylindrical battery cell 20. The projection of the end of the first circumferential surface 2321b away from the clearance opening 2321a in the thickness direction X of the wall is located inside the clearance opening 2321a. That is, the first circumferential surface 2321b 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 2321b a structure that gradually tilts outward from the end away from the wall 211 and toward the end near the wall 211 and away from the central axis of the cylindrical battery cell 20.

[0384] 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 273 and the orthographic projection of the first circumferential surface 2321b overlap. That is, at least a portion of the projection of the elastic region 273 in the thickness direction X of the wall is located on the first circumferential surface 2321b, such that at least a portion of the elastic region 273 is disposed corresponding to the first circumferential surface 2321b in the thickness direction X of the wall.

[0385] It should be noted that in the embodiment where the side wall of the clearance portion 2321 includes a first circumferential surface 2321b, and the first circumferential surface 2321b is inclined from the clearance opening 2321a toward the central axis of the cylindrical battery cell 20, in the projection plane perpendicular to the thickness direction X of the wall portion, at least a portion of the orthographic projection of the exposed area 2112 of the wall portion 211 can be a structure that overlaps with the orthographic projection of the first circumferential surface 2321b, that is, at least a portion of the projection of the exposed area 2112 in the thickness direction X of the wall portion is located within the first circumferential surface 2321b. Of course, it can also be a structure where the orthographic projection of the exposed area 2112 of the wall portion 211 is located inside the area defined by the orthographic projection of the first circumferential surface 2321b, that is, the projection of the exposed area 2112 in the thickness direction X of the wall portion is located inside the first circumferential surface 2321b.

[0386] In this embodiment, the first peripheral surface 2321b of the clearance portion 2321 is connected to the first surface 2322 at one end to form a clearance opening 2321a, and the clearance opening 2321a is located on the first surface 2322. By setting the first peripheral surface 2321b to be inclined from the clearance opening 2321a toward the central axis of the cylindrical battery cell 20, the first peripheral surface 2321b is an inclined surface that is larger at the end near the first surface 2322 and smaller at the end away from the first surface 2322 in the thickness direction X of the wall portion. The elastic region 273 and the first peripheral surface 2321b 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 2321b is a structure that corresponds to the elastic region 273 in the thickness direction X of the wall, so that the first peripheral surface 2321b of the avoidance part 2321 can fit the deformation of the elastic region 273, so that the avoidance part 2321 can avoid the elastic region 273, and can further expand the avoidance range of the avoidance part 2321 to the elastic region 273 without excessively reducing the first tab 232, thereby further improving the avoidance effect of the avoidance part 2321 to the elastic region 273 while meeting the overcurrent requirements of the first tab 232.

[0387] In some embodiments, as shown in FIG17, the first circumferential surface 2321b is a conical surface.

[0388] In this embodiment, by setting the first circumferential surface 2321b as a conical structure, it is beneficial to improve the regularity of the first circumferential surface 2321b, thereby further improving the avoidance effect of the avoidance part 2321 on the elastic area 273, and reducing the processing and forming difficulty of the first circumferential surface 2321b, so as to reduce the manufacturing difficulty of the cylindrical battery cell 20.

[0389] According to some embodiments of this application, as shown in Figures 15 and 16, the terminal connection area 272 is connected to the current collector body area 271 only through a single elastic area 273. That is, only one elastic area 273 connects a terminal connection area 272 and a current collector body area 271.

[0390] In this embodiment, by setting the terminal connection area 272 to be connected to the current collection body area 271 only through an elastic area 273, the elastic area 273 can be better deformed when the terminal connection area 272 and the current collection body area 271 move closer or further away from each other along the thickness direction X of the wall. This is beneficial to further expand the range of movement of the terminal connection area 272 relative to the current collection body area 271 in the thickness direction X of the wall.

[0391] Of course, the structure of the first current collector 27 is not limited to this. In some embodiments, the first current collector 27 can also have other structures. For example, the first current collector 27 includes multiple elastic regions 273, and the terminal connection region 272 is connected to the current collector body region 271 through the multiple elastic regions 273. That is, multiple elastic regions 273 are connected between a terminal connection region 272 and a current collector body region 271. It should be noted that in embodiments where the current collector body region 271 is an annular structure surrounding the terminal connection region 272, the multiple elastic regions 273 can also be a structure that is circumferentially spaced and asymmetrically arranged along the current collector body region 271.

[0392] In this embodiment, by setting the terminal connection area 272 to be interconnected with the current collection body area 271 through multiple elastic areas 273, it is beneficial to improve the connection reliability between the terminal connection area 272 and the current collection body area 271, and can further increase the current flow area between the terminal connection area 272 and the current collection body area 271.

[0393] According to some embodiments of this application, as shown in FIG15, the current collector body area 271, the elastic area 273, and the terminal connection area 272 are integrally formed. That is, the current collector body area 271, the elastic area 273, and the terminal connection area 272 of the first current collector component 27 are structures manufactured by an integral forming process, such as stamping, casting, or milling.

[0394] Of course, the current collection main body area 271, elastic area 273 and terminal connection area 272 of the first current collection component 27 can also be a separate structure. For example, the current collection main body area 271 is welded to the elastic area 273, and the elastic area 273 is welded to the terminal connection area 272.

[0395] In this embodiment, by setting the current collection body area 271, the elastic area 273, and the terminal connection area 272 of the first current collection component 27 as an integral structure, on the one hand, the connection difficulty between the elastic area 273 and the current collection body area 271 and the terminal connection area 272 can be reduced, thereby reducing the processing difficulty of the first current collection component 27. On the other hand, the connection reliability and stability between the current collection body area 271, the elastic area 273, and the terminal connection area 272 can be improved, which is conducive to alleviating the phenomenon of breakage between the current collection body area 271 and the elastic area 273 and between the elastic area 273 and the terminal connection area 272 during use, thereby reducing the risk of connection failure between the electrode terminal 22 and the electrode assembly 23.

[0396] According to some embodiments of this application, the Vickers hardness of the elastic region 273 is greater than or equal to 10 and less than or equal to 70.

[0397] For example, the Vickers hardness of the elastic region 273 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.

[0398] In this embodiment, by setting the Vickers hardness of the elastic region 273 to 10 to 70, the elastic region 273 has good structural strength and good deformation capacity. This allows the elastic region 273 to play a good buffering role between the current collector body region 271 and the terminal connection region 272, while also enabling the elastic region 273 to better support the terminal connection region 272. This helps to alleviate the phenomenon of poor assembly caused by the terminal connection region 272 failing to make effective contact with the electrode terminal 22.

[0399] According to some embodiments of this application, the material of the elastic region 273 includes aluminum.

[0400] For example, the entire material of the first current collector 27 is aluminum, and the material of the first tab 232 is aluminum, so that the tab connection area 274 of the first current collector 27 and the first tab 232 are welded together with the same material, which helps to reduce the welding difficulty.

[0401] In this embodiment, the use of aluminum material for the elastic region 273 enables the elastic region 273 to have good flow conduction ability while also enabling the elastic region 273 to have good deformation ability.

[0402] According to some embodiments of this application, referring to Figures 15 and 16, and further referring to Figure 18, Figure 18 is a cross-sectional view of the elastic region 273 of the first current collector 27 provided in some embodiments of this application, perpendicular to its extending direction. The elastic region 273 has its opposite ends in its extending direction connected to the current collector body region 271 and the terminal connection region 272, respectively, and the area of ​​the cross-section of the elastic region 273 perpendicular to its extending direction is S, satisfying 0.2 mm. 2 ≤S≤8mm 2 .

[0403] The area S of the cross-section of the elastic region 273 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.

[0404] In this embodiment, the area of ​​the cross-section of the elastic region 273 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 273 perpendicular to its extension direction is set to be greater than or equal to 0.2 mm. 2 This increases the flow area of ​​the elastic zone 273, thereby improving the flow capacity of the first current collector 27. On the other hand, the cross-sectional area of ​​the elastic zone 273 perpendicular to its extension direction is set to be less than or equal to 8 mm². 2This allows the elastic zone 273 to deform better between the current collector area 271 and the terminal connection area 272, which is beneficial to improving the deformation capability of the elastic zone 273.

[0405] In some embodiments, as shown in Figures 16 and 18, 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.

[0406] Wherein, the width direction of the cross-section of the elastic region 273 perpendicular to its extension direction is the thickness direction X of the wall. For example, the orthographic projection of the elastic region 273 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 273 perpendicular to its extension direction is perpendicular to the radial direction of the cylindrical battery cell 20.

[0407] For example, the length L of the cross section of the elastic region 273 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.

[0408] For example, the width W of the cross section of the elastic region 273 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.

[0409] In this embodiment, by setting the length of the cross-section of the elastic region 273 perpendicular to its extension direction to 1mm to 10mm, and setting the width of the cross-section of the elastic region 273 perpendicular to its extension direction to 0.2mm to 0.8mm, the elastic region 273 is made into a flat structure. The elastic region 273 with this structure can not only meet the flow requirements of the elastic region 273, but also improve the deformation capacity of the elastic region 273, and reduce the processing difficulty and space occupied by the elastic region 273.

[0410] According to some embodiments of this application, as shown in Figures 15 and 16, the current collection body area 271 is an annular structure surrounding the terminal connection area 272. The terminal connection area 272 and the current collection body area 271 are spaced apart, and the elastic area 273 is connected at opposite ends in its extending direction to the outer peripheral surface of the terminal connection area 272 and the inner peripheral surface of the current collection body area 271, respectively.

[0411] The elastic region 273 is connected to the outer peripheral surface of the terminal connection region 272 and the inner peripheral surface of the current collector region 271 at opposite ends in its extension direction. In other words, the elastic region 273 is a structure that connects the terminal connection region 272 and the current collector region 271 in the radial direction of the cylindrical battery cell 20.

[0412] In this embodiment, by setting the current collecting body region 271 as an annular structure surrounding the outer side of the terminal connection region 272, and the elastic region 273 having its two opposite ends connected to the outer peripheral surface of the terminal connection region 272 and the inner peripheral surface of the current collecting body region 271 respectively in its extending direction, the elastic region 273 is a structure connecting the terminal connection region 272 and the current collecting body region 271. The first current collecting member 27 with this structure is convenient for the elastic region 273 to deform and for the terminal connection region 272 to be assembled and connected with the electrode terminal 22, which helps to reduce the connection difficulty between the terminal connection region 272 and the electrode terminal 22. On the other hand, it can optimize the structural layout of the current collecting body region 271, the elastic region 273 and the terminal connection region 272, so that the current collecting body region 271 of the first current collecting member 27 can be assembled between the first insulating part 251 and the first electrode tab 232, which helps to improve the structural stability of the current collecting body region 271 of the first current collecting member 27 disposed between the first insulating part 251 and the first electrode tab 232.

[0413] In some embodiments, as shown in FIG16, the orthographic projection of the elastic region 273 extends radially along the cylindrical battery cell 20 in a projection plane perpendicular to the thickness direction X of the wall portion.

[0414] In this embodiment, by setting the orthographic projection of the elastic region 273 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 273 is a strip-shaped structure arranged radially along the cylindrical battery cell 20 between the current collector body region 271 and the terminal connection region 272. This facilitates the deformation of the elastic region 273 when the current collector body region 271 and the terminal connection region 272 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 273 between the current collector body region 271 and the terminal connection region 272, and can improve the effect of the elastic region 273 in absorbing the assembly error between the terminal connection region 272 and the electrode terminal 22. On the other hand, it can improve the regularity of the shape of the first current collector component 27, which helps to reduce the processing difficulty of the first current collector component 27.

[0415] According to some embodiments of this application, as shown in FIG16, the elastic region 273 is connected to the current collection body region 271 and the terminal connection region 272 at opposite ends in its extension direction, and the dimension of the elastic region 273 in its extension direction is D, and the radius of the current collection body region 271 is R, satisfying 0.4R≤D≤0.95R.

[0416] Wherein, the dimension D of the elastic zone 273 in its extension direction is the length of the elastic zone 273 in its extension direction, and the radius R of the main flow collection zone 271 is the radius of the circle containing the outer edge of the orthographic projection of the main flow collection zone 271 in the projection plane perpendicular to the thickness direction X of the wall.

[0417] For example, the dimension D of the elastic region 273 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 271.

[0418] In this embodiment, by setting the dimension D of the elastic region 273 in its extension direction to be greater than or equal to 0.4 times the radius R of the current collector 271, the elastic region 273 has sufficient length to deform. This is beneficial to improving the ability of the elastic region 273 to deform when the current collector 271 and the terminal connection area 272 move closer or further apart along the thickness direction X of the wall. In addition, by setting the dimension D of the elastic region 273 in its extension direction to be less than or equal to 0.95 times the radius R of the current collector 271, the phenomenon of the terminal connection area 272 being too small due to the excessive space occupied by the elastic region 273 is alleviated. This is beneficial to increasing the connection area between the terminal connection area 272 and the electrode terminal 22, thereby improving the current flow area and connection reliability between the terminal connection area 272 and the electrode terminal 22.

[0419] In some embodiments, please continue to refer to Figure 16, 8mm≤D≤25mm.

[0420] For example, the dimension D of the elastic region 273 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.

[0421] In this embodiment, by setting the dimension of the elastic region 273 in its extension direction to be greater than or equal to 8 mm, the elastic region 273 has sufficient length to deform, which is beneficial to further improve the ability of the elastic region 273 to deform when the current collector area 271 and the terminal connection area 272 move closer or further apart along the thickness direction X of the wall. In addition, by setting the dimension of the elastic region 273 in its extension direction to be less than or equal to 25 mm, the phenomenon of insufficient strength of the elastic region 273 caused by excessive length is alleviated, so that the elastic region 273 can better support the terminal connection area 272, thereby effectively alleviating the phenomenon of poor assembly caused by the terminal connection area 272 failing to make effective contact with the electrode terminal 22.

[0422] According to some embodiments of this application, referring to Figures 15 and 16, the first current collection member 27 may further include a base region 275, and the elastic region 273 is connected to the current collection body region 271 through the base region 275. In the projection plane perpendicular to the thickness direction X of the wall, the width of the orthographic projection of the base region 275 in the circumferential direction of the current collection body region 271 is greater than the width of the orthographic projection of the elastic region 273 in the circumferential direction of the current collection body region 271.

[0423] It should be noted that if the base region 275 has a uniform width, then the width of the base region 275 in the circumferential direction of the main flow collection region 271 is greater than the width of the elastic region 273 in the circumferential direction of the main flow collection region 271; if the base region 275 has a gradually changing width, then the minimum width of the base region 275 in the circumferential direction of the main flow collection region 271 is greater than or equal to the width of the elastic region 273 in the circumferential direction of the main flow collection region 271. For example, in Figures 12 and 15, if the width of the base region 275 in the circumferential direction of the main flow collection region 271 gradually increases from the end connected to the elastic region 273 to the end connected to the main flow collection region 271, then the width of the base region 275 at the end connected to the elastic region 273 is the minimum width of the base region 275 in the circumferential direction of the main flow collection region 271.

[0424] In this embodiment, the first current collecting component 27 is further provided with a base region 275 connecting the elastic region 273 and the current collecting main body region 271. The width of the base region 275 in the circumferential direction of the current collecting main body region 271 is greater than the width of the elastic region 273 in the circumferential direction of the current collecting main body region 271. This makes the elastic region 273 a structure that is connected to the current collecting main body region 271 through the base region 275 with a larger width. This helps to reduce the connection difficulty between the elastic region 273 and the annular current collecting main body region 271, and can improve the connection stability of the elastic region 273 connected to the inner circumferential surface of the current collecting main body region 271.

[0425] In some embodiments, as shown in Figures 15 and 16, the base region 275 has a first end 2751 and a second end 2752 opposite to each other. The first end 2751 is connected to the elastic region 273, and the second end 2752 is connected to the main collection body region 271. In a projection plane perpendicular to the thickness direction X of the wall, the width of the orthographic projection of the base region 275 onto the circumferential direction of the main collection body region 271 gradually increases from the first end 2751 to the second end 2752. That is, the width of the end of the base region 275 connected to the elastic region 273 is the minimum width of the base region 275 in the circumferential direction of the main collection body region 271, while the width of the end of the base region 275 connected to the inner circumferential surface of the main collection body region 271 is the maximum width of the base region 275 in the circumferential direction of the main collection body region 271.

[0426] In this embodiment, by configuring the base region 275 such that the width of the main body region 271 gradually increases from the first end 2751 connected to the elastic region 273 to the second end 2752 connected to the main body region 271 in the circumferential direction, the width of the end of the base region 275 connected to the elastic region 273 can be reduced. This helps to reduce the width difference at the connection position between the base region 275 and the elastic region 273, thereby reducing the difficulty of connecting and molding the base region 275 and the elastic region 273, and enabling the base region 275 and the elastic region 273 to achieve the desired connection. The transition at the connection position of the elastic zone 273 is smoother. On the other hand, the increased width of the second end 2752 connecting the base zone 275 and the main collection zone 271 can expand the angle at the connection position between the inner circumferential surfaces of the base zone 275 and the main collection zone 271, thereby alleviating the stress concentration at the connection position between the base zone 275 and the main collection zone 271. This helps to reduce the risk of damage or cracking at the connection position between the base zone 275 and the main collection zone 271, thereby improving the reliability and service life of the first collection component 27.

[0427] According to some embodiments of this application, please continue to refer to Figures 15 and 16. The first current collector 27 may further include a tab connection area 274, which is connected to the inner peripheral surface of the current collector body area 271 and is connected to the first tab 232 to electrically connect the current collector body area 271 and the first tab 232.

[0428] The tab connection area 274 is connected to the inner circumferential surface of the current collection main body area 271, that is, the tab connection area 274 is located on the inner circumferential side of the current collection main body area 271.

[0429] It should be noted that in other embodiments, the first current collector 27 may not have a tab connection area 274. Correspondingly, the current collector body area 271 is directly connected to the first tab 232.

[0430] Optionally, the tab connection area 274 and the current collector body area 271 are integrally formed, that is, the tab connection area 274 and the current collector body area 271 are an integral structure made by an integral forming process.

[0431] In this embodiment, the first current collector 27 is further provided with a tab connection area 274 for interconnecting with the first tab 232. The tab connection area 274 is connected to the inner circumferential surface of the current collector body area 271. On the one hand, this facilitates the connection between the current collector body area 271 and the first tab 232 through the tab connection area 274, which helps to reduce the connection difficulty between the first current collector 27 and the first tab 232 and increases the connection area between the first current collector 27 and the first tab 232. On the other hand, it optimizes the structural layout between the tab connection area 274 and the current collector body area 271, so that the current collector body area 271 of the first current collector 27 can be assembled between the first insulating part 251 and the first tab 232, which helps to improve the structural stability of the current collector body area 271 of the first current collector 27 disposed between the first insulating part 251 and the first tab 232.

[0432] In some embodiments, as shown in FIG16, the tab connection region 274 extends radially along the cylindrical battery cell 20.

[0433] In this embodiment, by setting the tab connection area 274 to extend radially along the cylindrical battery cell 20, the connection area between the tab connection area 274 and the first tab 232 can be increased, thereby improving the connection stability between the tab connection area 274 and the first tab 232. Furthermore, the first tab 232 can be connected to the tab connection area 274 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 are connected to the tab connection area 274. This improves the current flow area between the first tab 232 and the tab connection area 274, and enhances the current flow balance between the electrode assembly 23 and the tab connection area 274, thereby reducing the risk of localized lithium plating in the electrode assembly 23 during use.

[0434] According to some embodiments of this application, referring to Figures 15 and 16, in the projection plane perpendicular to the thickness direction X of the wall, the orthographic projections of the terminal connection area 272 and the elastic area 273 do not overlap with the orthographic projection of the tab connection area 274. That is, the projections of the terminal connection area 272, the elastic area 273, and the tab connection area 274 in the thickness direction X of the wall do not overlap with each other.

[0435] In this embodiment, by setting the projections of the terminal connection area 272 and the elastic area 273 onto the thickness direction X of the wall to be non-overlapping with the projection of the tab connection area 274 onto the thickness direction X of the wall, the obstruction and interference of the tab connection area 274 on the terminal connection area 272 and the elastic area 273 can be reduced when the terminal connection area 272 is close to or far from the current collector body area 271 on the thickness direction X of the wall. This is beneficial to expanding the movement range of the terminal connection area 272 relative to the current collector body area 271 on the thickness direction X of the wall, and can also improve the deformation degree of the elastic area 273 on the thickness direction X of the wall. This can further improve the effect of the elastic area 273 in reducing the assembly error between the electrode terminal 22 and the terminal connection area 272, thereby further improving the assembly quality between the electrode terminal 22 and the terminal connection area 272, and further improving the buffering effect of the elastic area 273 between the current collector body area and the terminal connection area 272, thereby further reducing the risk of electrical connection failure between the electrode terminal 22 and the electrode assembly 23.

[0436] In some embodiments, please continue to refer to Figures 15 and 16, the first current collector 27 may include a plurality of tab connection regions 274, which are arranged at circumferential intervals along the current collector body region 271.

[0437] For example, the first current collector 27 is provided with four tab connection areas 274, all of which are connected to the inner circumferential surface of the current collector body area 271. The four tab connection areas 274 are spaced apart and evenly arranged along the circumference of the current collector body area 271, and each tab connection area 274 is a structure that extends radially along the cylindrical battery cell 20. Of course, in other embodiments, the number of tab connection areas 274 connected on the current collector body area 271 can also be two, three, five, or six, etc.

[0438] In this embodiment, by connecting multiple tab connection areas 274 on the current collector main body region 271, and the multiple tab connection areas 274 are arranged at intervals along the circumference of the current collector main body region 271, on the one hand, the connection area between the first current collector component 27 and the first tab 232 can be further increased, thereby increasing the flow area between the first current collector component 27 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 with tab connection areas 274, which is beneficial to improving the flow balance between the electrode assembly 23 and the first current collector component 27, thereby reducing the risk of local lithium plating in the electrode assembly 23 during use.

[0439] According to some embodiments of this application, referring to Figures 6 and 15, the terminal connection area 272 and the electrode terminal 22 are welded together at one end of the wall portion near the main body portion 231 in the thickness direction X. That is, the terminal connection area 272 and the electrode terminal 22 are stacked and welded together along the thickness direction X of the wall portion. Correspondingly, the second surface 2721 of the terminal connection area 272 and the connection surface 223 of the electrode terminal 22 abut against each other and are welded together.

[0440] For example, the terminal connection area 272 can be welded to the electrode terminal 22 in various ways, such as laser welding or ultrasonic welding.

[0441] In this embodiment, by configuring the terminal connection area 272 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 272 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 272 and the electrode terminal 22. On the other hand, under the action of the elastic area 273, it can absorb the assembly error between the electrode terminal 22 and the terminal connection area 272, thereby alleviating the welding gap between the terminal connection area 272 and the electrode terminal 22. This helps to reduce the risk of poor soldering between the terminal connection area 272 and the electrode terminal 22, thereby improving the welding quality between the terminal connection area 272 and the electrode terminal 22.

[0442] In some embodiments, referring to Figures 6, 10, and 15, 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 272 is welded to the electrode terminal 22 to form a connection portion 30, and the projection of the connection portion 30 along the thickness direction X of the wall is located within the central through-hole 234.

[0443] In this case, along the thickness direction X of the wall portion, the projection of the connecting portion 30 is located inside the central through hole 234. That is, in the projection plane perpendicular to the thickness direction X of the wall portion, the orthographic projection of the connecting portion 30 is located inside the orthographic projection of the hole wall surface of the central through hole 234.

[0444] In this embodiment, by setting the connection portion 30 formed by welding the terminal connection area 272 and the electrode terminal 22 together, the projection of the connection portion 30 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 272 away from the electrode terminal 22 through the central through hole 234 when welding the terminal connection area 272 and the electrode terminal 22 together. This helps to reduce the power required for welding the terminal connection area 272 and the electrode terminal 22 together, thereby reducing the welding difficulty between the terminal connection area 272 and the electrode terminal 22, and improving the welding quality between the terminal connection area 272 and the electrode terminal 22, thereby improving the connection reliability between the terminal connection area 272 and the electrode terminal 22.

[0445] According to some embodiments of this application, referring to Figures 6 and 8, the electrode terminal 22 may include a terminal body 221 and a protrusion 222. The terminal body 221 is disposed in the mounting hole 2111 and connected to the wall portion 211. The terminal body 221 extends along the thickness direction X of the wall portion into the through hole 2511. The sealing member 24 is disposed between the terminal body 221 and the wall portion 211, and the terminal body 221 includes a first limiting portion 2211. 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 272.

[0446] 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 24 is provided between the terminal body 221 and the wall portion 211. The sealing member 24 is configured to seal the gap between the terminal body 221 and the hole wall surface of the mounting hole 2111. The sealing member 24 is made of insulating material, so that the sealing member 24 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.

[0447] 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 272. That is, the protrusion 222 is a convex structure that protrudes from one end of the terminal body 221 facing the terminal connection area 272 in the thickness direction X of the wall portion, and the protrusion 222 is connected to the terminal connection area 272. For example, the protrusion 222 is welded to the terminal connection area 272 to form a connection portion 30. Correspondingly, in an embodiment where the electrode terminal 22 has a connection surface 223 that is connected to the terminal connection area 272, the end face of the protrusion 222 facing the terminal connection area 272 in the thickness direction X of the wall portion is the connection surface 223 of the electrode terminal 22.

[0448] 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 terminal body 221 is inserted into the through hole 2511 along the thickness direction X of the wall portion, and the protrusion 222 is connected to the terminal connection area 272 of the first current collector 27. The electrode terminal 22 with this structure can reduce the connection difficulty between the electrode terminal 22 and the terminal connection area 272 and reduce the interference between the terminal connection area 272 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 272 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 272, thereby effectively improving the assembly quality between the terminal connection area 272 and the electrode terminal 22.

[0449] In some embodiments, as shown in Figures 6, 7 and 8, the protrusion 222 protrudes from the surface of the first insulating portion 251 facing the first current collector 27 along the thickness direction X of the wall portion, that is, the protrusion 222 protrudes from the third surface 2512 of the first insulating portion 251 facing the first current collector 27 in the thickness direction X of the wall portion.

[0450] The terminal body 221 of the electrode terminal 22 extends along the thickness direction X of the wall into the through hole 2511 of the first insulating part 251. The protrusion 222 protrudes from the surface of the first insulating part 251 facing the first current collector 27. That is, the protrusion 222 is a structure in which the through hole 2511 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 272 in the thickness direction X of the wall is farther away from the wall 211 than the surface of the first insulating part 251 facing the first current collector 27.

[0451] In this embodiment, by setting the protrusion 222 to protrude from the surface of the first insulating portion 251 facing the first current collector 27 in the thickness direction X of the wall portion, the obstruction and interference of the first insulating portion 251 on the protrusion 222 can be reduced, so that the protrusion 222 and the terminal connection area 272 can be connected to each other, which helps to reduce the connection difficulty between the protrusion 222 and the terminal connection area 272.

[0452] According to some embodiments of this application, as shown in Figures 6, 12 and 14, the first insulating portion 251 is bonded to the wall portion 211.

[0453] For example, the first insulating part 251 can be bonded to the surface of the wall part 211 facing the first insulating part 251 by means of adhesive, double-sided tape or hot melt adhesive.

[0454] In this embodiment, by setting the first insulating part 251 to be bonded to the wall part 211, the assembly difficulty between the first insulating part 25 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 25 disposed in the outer casing 21 can be improved, which is beneficial to reducing the risk of the first insulating part 25 shifting or shaking during use.

[0455] According to some embodiments of this application, referring to Figures 4, 6, and 7, the first insulating member 25 may further include a second insulating portion 252, which surrounds the first insulating portion 251, and the second insulating portion 252 and the first insulating portion 251 together define a receiving space 253. Along the thickness direction X of the wall portion, the first electrode tab 232 is received within the receiving space 253.

[0456] In this embodiment, the second insulating part 252 is connected to the first insulating part 251 at one end near the wall part 211 in the thickness direction X of the wall part, so that the first insulating member 25 is a hollow structure with one end open. In the embodiment where the first insulating part 251 is provided with a through hole 2511, the through hole 2511 is connected to the accommodating space 253.

[0457] The first tab 232 is accommodated within the accommodating space 253 along the thickness direction X of the wall portion, that is, the first insulating member 25 is sleeved on the end of the electrode assembly 23 where the first tab 232 is provided. It should be noted that in the embodiment where the cylindrical battery cell 20 also includes a first current collector 27, and the first current collector 27 is disposed between the first tab 232 and the first insulating portion 251 along the thickness direction X of the wall portion, the first current collector 27 is accommodated within the accommodating space 253.

[0458] For example, the first insulating portion 251 and the second insulating portion 252 of the first insulating member 25 are integrally formed.

[0459] In this embodiment, the first insulating member 25 is further provided with a second insulating part 252 surrounding the first insulating part 251, and the first insulating part 251 and the second insulating part 252 together form a receiving space 253 for accommodating the first electrode tab 232. The cylindrical battery cell 20 with this structure is convenient for assembling the first insulating member 25. Only one end of the electrode assembly 23 with the first electrode tab 232 needs to be inserted into the receiving space 253 of the first insulating member 25 to complete the assembly between the first insulating member 25 and the electrode assembly 23, which helps to reduce the assembly difficulty between the first insulating member 25 and the electrode assembly 23. On the other hand, the second insulating part 252 can further separate the first electrode tab 232 from the outer shell 21, which helps to improve the insulation and isolation effect of the first insulating member 25 on the first electrode tab 232 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.

[0460] In some embodiments, as shown in Figures 6 and 7, one end of the main body 231, where the first electrode tab 232 is provided, is accommodated within the accommodating space 253 along the thickness direction X of the wall. That is, the first electrode tab 232 is entirely located within the accommodating space 253 formed by the first insulating member 25 along the thickness direction X of the wall.

[0461] 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 253 in the thickness direction X of the wall, the first tab 232 is housed entirely in the housing space 253, thereby further improving the insulation effect of the first insulating member 25 on the first tab 232 and the outer shell 21, and further reducing the risk of short circuit in the cylindrical battery cell 20 during use.

[0462] According to some embodiments of this application, referring to Figures 4 and 5, and further referring to Figure 19, Figure 19 is a structural schematic diagram of the second current collector 28 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 28, 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 28 to electrically connect the electrode assembly 23 and the side wall 2123.

[0463] 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 both 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.

[0464] 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.

[0465] Optionally, the connection structure between the protrusion 2123a and the second current collector 28 can be various, such as welding connection or abutment.

[0466] 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 28 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 28 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 28 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.

[0467] According to some embodiments of this application, as shown in Figures 5 and 19, the second current collector 28 may include a first connection region 281, a second connection region 282, and a third connection region 283. The first connection region 281 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 tab 233. The second connection region 282 is connected to the protrusion 2123a. The third connection region 283 connects the first connection region 281 and the second connection region 282, and is configured to deform when the first connection region 281 and the second connection region 282 move closer or further apart along the thickness direction X of the wall portion.

[0468] The first connection area 281 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 281 of the second current collector 28 is located on the side of the second tab 233 away from the main body 231 in the thickness direction X of the wall.

[0469] For example, the first connection area 281 is welded to the second electrode 233. Of course, in other embodiments, the first connection area 281 and the second electrode 233 may also be abutting each other.

[0470] The third connecting region 283 is a structure connecting the first connecting region 281 and the second connecting region 282. The third connecting region 283 is configured to deform when the first connecting region 281 and the second connecting region 282 move closer or further away from each other along the thickness direction X of the wall. That is, when the second current collecting member 28 is compressed or stretched in the thickness direction X of the wall, the third connecting region 283 can deform when the first connecting region 281 and the second connecting region 282 move closer or further away from each other. It should be noted that the deformation of the third connecting region 283 can be either elastic or plastic.

[0471] Optionally, in Figure 19, the second current collection component 28 is provided with a plurality of second connection areas 282 and a plurality of third connection areas 283. The plurality of third connection areas 283 are arranged circumferentially along the sidewall 2123 and are all connected to the first connection area 281. Correspondingly, the plurality of second connection areas 282 are arranged circumferentially along the sidewall 2123. Each second connection area 282 is connected to the first connection area 281 through a third connection area 283, and each second connection area 282 is connected to the protrusion 2123a.

[0472] For example, the second connection area 282 is an arc-shaped structure extending circumferentially along the sidewall 2123.

[0473] For example, in FIG19, the second current collector 28 is provided with four second connection areas 282 and four third connection areas 283, and each second connection area 282 is connected to the first connection area 281 through a third connection area 283. Of course, in other embodiments, the number of second connection areas 282 of the second current collector 28 can also be two, three, five or six, etc.

[0474] Optionally, the first connection area 281, the second connection area 282, and the third connection area 283 of the second current collector 28 can be an integrally formed structure or a separate but connected structure. For example, in FIG19, the first connection area 281, the second connection area 282, and the third connection area 283 of the second current collector 28 are integral structures formed by integral forming processes such as stamping and cutting.

[0475] In this embodiment, the second current collector 28 is provided with a first connecting region 281, a second connecting region 282, and a third connecting region 283. The first connecting region 281 and the second connecting region 282 are respectively connected to the second electrode 233 and the protrusion 2123a, and the third connecting region 283 is connected between the first connecting region 281 and the second connecting region 282, so as to realize that the second electrode 233 is electrically connected to the side wall 2123 through the second current collector 28. The third connecting region 283 is configured to deform when the first connecting region 281 and the second connecting region 282 move closer or further apart along the thickness direction X of the wall. This allows the third connection area 283 to act as a buffer between the first connection area 281 and the second connection area 282, thereby alleviating the rigid tension between the first connection area 281 and the second connection area 282, between the first connection area 281 and the second tab 233, and between the second connection area 282 and the protrusion 2123a during the shaking or displacement of the electrode assembly 23. This helps to further reduce the risk of connection failure between the first connection area 281 and the second tab 233, and between the second connection area 282 and the protrusion 2123a, and also helps to reduce the phenomenon of the second current collector 28 being damaged by tension.

[0476] According to some embodiments of this application, as shown in FIG19, the third connection area 283 is bent to form a plurality of bent segments 2831, the plurality of bent segments 2831 are connected in sequence, and the bent segments 2831 located at both ends of the plurality of bent segments 2831 are respectively connected to the first connection area 281 and the second connection area 282.

[0477] The third connecting region 283 is bent to form multiple bent segments 2831, which are connected in sequence. In other words, the third connecting region 283 is a structure with a local bending, which results in multiple bent segments 2831 connected in sequence in the third connecting region 283, and each pair of adjacent bent segments 2831 are set at an acute angle, a right angle or an obtuse angle.

[0478] For example, in Figure 19, the third connecting region 283 is bent to form three bent segments 2831 connected in sequence, and the two bent segments 2831 located at both ends of the three bent segments 2831 are respectively connected to the first connecting region 281 and the second connecting region 282. Of course, in other embodiments, the number of bent segments 2831 formed by bending the third connecting region 283 can also be two, four, five or six, etc.

[0479] In this embodiment, by setting the third connecting area 283 as a structure of bending to form a plurality of sequentially connected bent segments 2831, and the bent segments 2831 located at both ends of the plurality of bent segments 2831 being connected to the first connecting area 281 and the second connecting area 282 respectively, the deformation capacity of the third connecting area 283 when the first connecting area 281 and the second connecting area 282 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 283 between the first connecting area 281 and the second connecting area 282, and further reduce the phenomenon of rigid tension between the first connecting area 281 and the second connecting area 282, between the first connecting area 281 and the second tab 233, and between the second connecting area 282 and the protrusion 2123a.

[0480] According to some embodiments of this application, as shown in FIG5 and FIG19, the second current collector 28 includes a second connection region 282 connected to the protrusion 2123a. Along the thickness direction X of the wall portion, the second connection region 282 is located on the side of the protrusion 2123a away from the wall portion 211.

[0481] For example, the second connection area 282 of the second current collector 28 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 282 is welded to the surface of the protrusion 2123a on the side away from the wall portion 211.

[0482] It should be noted that in other embodiments, the second connection area 282 may also be a structure located on the side of the protrusion 2123a facing the wall portion 211 and connected to the protrusion 2123a.

[0483] In this embodiment, by setting the second connection area 282 of the second current collector 28 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 282 of the second current collector 28 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 282 and the protrusion 2123a, and can reduce the obstruction of the main body portion 231 on the second connection area 282, which is beneficial to reduce the connection difficulty between the second connection area 282 and the protrusion 2123a, thereby reducing the assembly difficulty of the cylindrical battery cell 20.

[0484] According to some embodiments of this application, the second current collector 28 is welded to the protrusion 2123a.

[0485] For example, the second connection area 282 of the second current collector 28 is welded to the protrusion 2123a.

[0486] In this embodiment, by setting the second current collector 28 and the protrusion 2123a as a welded connection, it is beneficial to improve the connection stability and reliability between the second current collector 28 and the protrusion 2123a, so as to reduce the risk of connection failure during use.

[0487] According to some embodiments of this application, referring to FIG5, the protrusion 2123a is an annular structure extending circumferentially along the sidewall 2123.

[0488] 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, the protrusion 2123a can be connected to the second current collector 28 at any position in the circumferential direction of the sidewall 2123, so that the second current collector 28 and the protrusion 2123a can be assembled and connected to each other. This allows the assembly connection between the second current collector 28 and the protrusion 2123a to be achieved without rotating and adjusting the position and positioning of the second current collector 28 after it is assembled into the housing 21, which helps to further reduce the connection difficulty between the second current collector 28 and the protrusion 2123a, thereby effectively improving the assembly efficiency of the cylindrical battery cell 20.

[0489] 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.

[0490] 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.

[0491] 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 28. It also enables the protrusion 2123a to have the ability of elastic deformation, which helps to further alleviate the rigid tension between the second current collector 28 and the protrusion 2123a, thereby reducing the risk of connection failure between the second current collector 28 and the protrusion 2123a.

[0492] 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.

[0493] 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.

[0494] 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 insulating portion 251 of the first insulating member 25 is disposed between the first electrode tab 232 of the electrode assembly 23 and the bottom wall 2122 of the housing 212.

[0495] 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.

[0496] 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 may 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 insulating portion 251 of the first insulating member 25 is disposed between the first tab 232 of the electrode assembly 23 and the end cap 213.

[0497] 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 insulating member 25 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.

[0498] 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.

[0499] As shown in Figure 2, the battery device 100 may also include a housing 10, in which cylindrical battery cells 20 are housed.

[0500] 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.

[0501] 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.

[0502] 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.

[0503] 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.

[0504] 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.

[0505] 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.

[0506] 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.

[0507] The electrical device can be any of the aforementioned devices or systems that utilize cylindrical battery cells 20.

[0508] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0509] 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 whose thickness direction is the axial direction of the cylindrical battery cell, and the wall portion is provided with a mounting hole that penetrates the wall portion along its thickness direction; An electrode terminal is disposed in the mounting hole, and the electrode terminal includes a first limiting portion located on the side of the wall facing the interior of the housing; An electrode assembly is housed within the housing. The electrode assembly includes a main body and a first electrode tab. The first electrode tab protrudes from one end of the main body facing the wall and is electrically connected to the electrode terminal. The sealing element is made of insulating material. The sealing element includes a first sealing part, which is located between the wall and the first limiting part in the thickness direction of the wall, and the first sealing part extends beyond the first limiting part in the radial direction of the cylindrical battery cell in a direction away from the central axis of the cylindrical battery cell. as well as The first insulating member includes a first insulating portion disposed between the wall portion and the first electrode tab in the thickness direction of the wall portion. The first insulating portion is provided with a through hole, which penetrates the first insulating portion along the thickness direction of the wall portion. At least a portion of the first sealing portion and the first limiting portion are located 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. The wall portion has an exposed area corresponding to the first gap in the thickness direction of the wall portion. Along the thickness direction of the wall portion, the first tab has a first surface facing the wall portion. The first surface is provided with a relief portion recessed in a direction away from the wall portion. The projection of the exposed area in the thickness direction of the wall portion is located within the relief portion.

2. The cylindrical battery cell according to claim 1, 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.

3. The cylindrical battery cell according to claim 1 or 2, 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.

4. The cylindrical battery cell according to claim 3, 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 diameter of the first hole segment is smaller than the diameter of the second hole segment.

5. The cylindrical battery cell according to claim 3, 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 diameter of the first hole segment is equal to the diameter of the second hole segment.

6. The cylindrical battery cell according to any one of claims 1-5, wherein, The electrode terminal includes a terminal body disposed in the mounting hole, and the terminal body is connected to the wall portion. The terminal body includes the first limiting portion. The terminal body extends into the through hole along the thickness direction of the wall portion, and the sealing member further includes a second sealing portion located between the terminal body and the hole wall surface of the mounting hole to seal the gap between the terminal body and the hole wall surface of the mounting hole.

7. The cylindrical battery cell according to claim 6, wherein, The terminal body further includes a second limiting portion located on the side of the wall portion away from the interior of the housing. 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. The sealing element further includes a third sealing portion, which is located between the wall portion and the second limiting portion in the thickness direction of the wall portion to seal the gap between the wall portion and the second limiting portion.

8. The cylindrical battery cell according to any one of claims 1-7, wherein, The cylindrical battery cell also includes: The second insulating member is located between the wall portion and the first tab 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.

9. The cylindrical battery cell according to claim 8, wherein, The second insulating element protrudes from the wall surface of the through hole.

10. The cylindrical battery cell according to claim 9, wherein, The second insulating component is integrally formed with the first insulating part.

11. The cylindrical battery cell according to claim 8, wherein, The cylindrical battery cell further includes a first current collector, which is disposed between the first insulating portion and the first electrode tab. The first current collector connects the electrode terminal and the first electrode tab to electrically connect the electrode terminal and the first electrode tab. 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.

12. The cylindrical battery cell according to claim 11, wherein, The second insulating member is connected to the surface of the first current collector member facing the first insulating part.

13. The cylindrical battery cell according to claim 11, wherein, The second insulating element is connected to the surface of the first insulating portion facing the first current collecting member.

14. The cylindrical battery cell according to any one of claims 11-13, wherein, The first current collector includes a terminal connection area, which is connected to the electrode terminal; In the 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.

15. The cylindrical battery cell according to claim 14, 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.

16. The cylindrical battery cell according to claim 8, wherein, Along the thickness direction of the wall portion, the second insulating member is disposed between the first insulating portion and the wall portion.

17. The cylindrical battery cell according to claim 16, wherein, The second insulating member is connected to the surface of the wall portion facing the first insulating portion.

18. The cylindrical battery cell according to claim 16 or 17, 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.

19. The cylindrical battery cell according to any one of claims 11-18, 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.

20. The cylindrical battery cell according to any one of claims 1-19, wherein, The cylindrical battery cell also includes: A first current collector is disposed between the first insulating portion and the first electrode tab along the thickness direction of the wall portion, and the first current collector connects the electrode terminal and the first electrode tab to electrically connect the first electrode tab and the electrode terminal.

21. The cylindrical battery cell according to claim 20, wherein, The first flow collector has a hollow area, and the projection of the exposed area along the thickness direction of the wall is located within the hollow area.

22. The cylindrical battery cell according to claim 20 or 21, wherein, The first current collection component includes: The current collecting body region is at least partially disposed between the first insulating portion and the first electrode tab in the thickness direction of the wall portion, and the current collecting body region is electrically connected to the first electrode tab; Terminal connection area, connected to the electrode terminal; An elastic region connects the current collector body area and the terminal connection area, and the elastic region is configured to be deformable.

23. The cylindrical battery cell according to claim 22, 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.

24. The cylindrical battery cell according to claim 22 or 23, 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.

25. The cylindrical battery cell according to any one of claims 22-24, 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 second surface facing away from the main body portion. The electrode terminals have a connection surface facing the main body portion. The connection surface and the second surface are welded together.

26. The cylindrical battery cell according to claim 25, wherein, Along the thickness direction of the wall portion, the first insulating portion has a third surface facing the first electrode tab, and the third surface is further away from the main body portion than the connecting surface.

27. The cylindrical battery cell according to claim 26, wherein, Along the thickness direction of the wall portion, the flow collection main body region has a fourth surface that is away from the main body portion, and the fourth surface is further away from the main body portion than the second surface.

28. The cylindrical battery cell according to claim 27, wherein, Along the thickness direction of the wall portion, the terminal connection area has a fifth surface facing the main body portion, and the current collection main body area has a sixth surface facing the main body portion, the sixth surface being further away from the main body portion than the fifth surface.

29. The cylindrical battery cell according to claim 27 or 28, wherein, Along the thickness direction of the wall portion, at least a portion of the terminal connection area is accommodated within the clearance portion.

30. The cylindrical battery cell according to claim 25, wherein, Along the thickness direction of the wall portion, the flow collection main body region has a fourth surface facing away from the main body portion, and the fourth surface is closer to the main body portion than the second surface.

31. The cylindrical battery cell according to claim 30, wherein, Along the thickness direction of the wall portion, the first insulating portion has a third surface facing the first electrode tab, and the third surface is closer to the main body portion than the connecting surface.

32. The cylindrical battery cell according to claim 31, wherein, Along the thickness direction of the wall portion, at least a portion of the terminal connection area is accommodated within the through hole.

33. The cylindrical battery cell according to any one of claims 27-32, wherein, At least a portion of the elastic zone deforms and bends.

34. The cylindrical battery cell according to any one of claims 22-33, wherein, Along the thickness direction of the wall portion, the projection of the terminal connection area is located within the clearance portion.

35. The cylindrical battery cell according to claim 34, 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.

36. The cylindrical battery cell according to claim 35, wherein, The current collection main area abuts against the first surface, the clearance part forms a clearance opening on the first surface, the side wall of the clearance part includes a first circumferential surface, and the clearance opening is formed at one end of the first circumferential surface connected to the first surface along the thickness direction of the wall part. 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.

37. The cylindrical battery cell according to claim 36, wherein, The first circumferential surface is a conical surface.

38. The cylindrical battery cell according to any one of claims 22-37, wherein, The terminal connection area is connected to the current collection body area only through one of the elastic areas.

39. The cylindrical battery cell according to any one of claims 22-37, 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.

40. The cylindrical battery cell according to any one of claims 22-39, wherein, The current collection body area, the elastic area, and the terminal connection area are integrally formed.

41. The cylindrical battery cell according to any one of claims 22-40, wherein, The Vickers hardness of the elastic zone is greater than or equal to 10 and less than or equal to 70.

42. The cylindrical battery cell according to any one of claims 22-41, wherein, The material of the elastic zone includes aluminum.

43. The cylindrical battery cell according to any one of claims 22-42, wherein, The elastic region is connected to the current collector body area and the terminal connection area at opposite ends in its extending direction, and the area of ​​the cross-section of the elastic region perpendicular to its extending direction is S, satisfying 0.2mm. 2 ≤S≤8mm 2 .

44. The cylindrical battery cell according to claim 43, wherein, The cross-section is rectangular, and the length and width of the cross-section are L and W, respectively, satisfying that 1mm≤L≤10mm and 0.2mm≤W≤0.8mm.

45. The cylindrical battery cell according to any one of claims 22-44, 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.

46. ​​The cylindrical battery cell according to claim 45, 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.

47. The cylindrical battery cell according to claim 46, 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.

48. The cylindrical battery cell according to claim 47, wherein, 8mm≤D≤25mm.

49. The cylindrical battery cell according to any one of claims 46-48, 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.

50. The cylindrical battery cell according to claim 49, 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.

51. The cylindrical battery cell according to any one of claims 45-50, 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.

52. The cylindrical battery cell according to claim 51, wherein, The tab connection area extends radially along the cylindrical battery cell.

53. The cylindrical battery cell according to claim 51 or 52, 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.

54. The cylindrical battery cell according to any one of claims 51-53, 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.

55. The cylindrical battery cell according to any one of claims 22-54, 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.

56. The cylindrical battery cell according to claim 55, 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.

57. The cylindrical battery cell according to any one of claims 22-56, wherein, The electrode terminals include: A terminal body is disposed in the mounting hole and connected to the wall portion. The terminal body extends into the through hole along the thickness direction of the wall portion. The sealing member is disposed between the terminal body and the wall portion. The terminal body includes the first limiting 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.

58. The cylindrical battery cell according to claim 57, wherein, Along the thickness direction of the wall portion, the protrusion extends beyond the surface of the first insulating portion facing the first current collecting member.

59. The cylindrical battery cell according to any one of claims 1-58, wherein, The first insulating part is bonded to the wall part.

60. The cylindrical battery cell according to any one of claims 1-59, 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 electrode tab is accommodated within the accommodating space along the thickness direction of the wall portion.

61. The cylindrical battery cell according to claim 60, 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.

62. The cylindrical battery cell according to any one of claims 1-61, 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.

63. The cylindrical battery cell according to claim 62, 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.

64. The cylindrical battery cell according to claim 63, 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.

65. The cylindrical battery cell according to any one of claims 62-64, 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.

66. The cylindrical battery cell according to any one of claims 62-65, wherein, The second current collector is welded to the protrusion.

67. The cylindrical battery cell according to any one of claims 62-66, wherein, The protrusion is a ring-shaped structure extending circumferentially along the sidewall.

68. The cylindrical battery cell according to any one of claims 62-67, wherein, The sidewall is located away from the electrode assembly and has a groove formed at the position corresponding to the protrusion.

69. The cylindrical battery cell according to any one of claims 1-68, 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 forms an opening. The sidewall and the bottom wall together define a receiving cavity, in which the electrode assembly is received. End cap, to close the opening; The bottom wall is the wall portion.

70. The cylindrical battery cell according to any one of claims 1-68, wherein, The outer casing includes: The housing has an internally formed receiving cavity with an opening, and the electrode assembly is received within the receiving cavity; End cap, to close the opening; The end cap is the wall portion.

71. A battery device comprising a cylindrical battery cell as claimed in any one of claims 1-70.

72. An electrical device comprising a cylindrical battery cell as claimed in any one of claims 1-70, the cylindrical battery cell being used to provide electrical energy.

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