Battery cell, battery, and electrical device

Abstract

A battery cell (20), a battery (100), and an electrical device. The battery cell (20) comprises a casing (21), a first electrode terminal (22), an electrode assembly (23), a first current collecting member (24), and a connecting member (25). The casing (21) has a wall portion. The first electrode terminal (22) is insulatively mounted on the casing (21). The electrode assembly (23) is accommodated in the casing (21), the electrode assembly (23) comprises a main body portion (231) and a first tab (232), and the first tab (232) is arranged on the main body portion (231). The first current collecting member (24) is arranged in the casing (21), and the first current collecting member (24) is electrically connected to the first electrode terminal (22) and the first tab (232). The connecting member (25) is electrically connected to the wall portion (211) and the first current collecting member (24), and the minimum flow-through area of the connecting member (25) is smaller than the minimum flow-through area of the first current collecting member (24). In this way, heat generated by the connecting member when the battery cell is short-circuited is higher and the heat is accumulated faster, so that the connecting member can be fused prior to the first current collecting member, thereby cutting off a short-circuit path to mitigate phenomena such as information acquisition device damage, and improving the use reliability of the battery cell (20).

Description

Battery cells, batteries and electrical devices Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Art

[0002] In recent years, new energy vehicles have experienced rapid development. In the electric vehicle sector, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also growing. As a core component of new energy vehicles, batteries have high requirements in terms of reliability and service life.

[0003] In battery technology, to ensure the safety of battery cells, information collection equipment is generally used to monitor the usage information of battery cells to obtain the usage status of the battery cells. However, the existing battery cells are very prone to damage to the information collection equipment during the performance monitoring process, and the battery cells are very prone to short circuit risks, resulting in low reliability of the battery cells.

[0004] Summary of the Invention

[0005] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can effectively improve the reliability of the battery cell.

[0006] In a first aspect, an embodiment of the present application provides a battery cell, comprising a shell, a first electrode terminal, an electrode assembly, a first current collecting member and a connector; the shell has a wall portion; the first electrode terminal is insulated and mounted on the shell; the electrode assembly is accommodated in the shell, the electrode assembly comprises a main body portion and a first electrode tab, the first electrode tab is arranged on the main body portion; the first current collecting member is arranged in the shell, the first current collecting member electrically connects the first electrode terminal and the first electrode tab; the connector electrically connects the wall portion and the first current collecting member, and the minimum flow area of ​​the connector is smaller than the minimum flow area of ​​the first current collecting member.

[0007] In the above technical solution, a connector is further provided in the battery cell, and the first current collecting member and the wall of the shell are connected by the connector, so that the positive electrode or the negative electrode of the electrode assembly can be electrically connected to the shell, so that the information collection device can collect the usage information of the battery cell after being electrically connected to the shell, thereby facilitating the information collection device to connect the battery cell and collect data, which is conducive to reducing the difficulty of data collection of the battery cell, wherein, by setting the minimum flow area of ​​the connector to be smaller than the minimum flow area of ​​the first current collecting member, so that the minimum cross-sectional area of ​​the connector on the path for current to pass is smaller than the minimum cross-sectional area of ​​the first current collecting member on the path for current to pass, The resistance of the connector at the minimum flow area is greater than the resistance of the first current collecting component. Therefore, within the same time, the heat generated by the connector when the electrode assembly inside the battery cell and the shell overlap and short-circuit occurs is higher and the heat accumulates faster, so that the connector can be melted preferentially compared to the first current collecting component when the electrode assembly inside the battery cell and the shell overlap and short-circuit occurs, so that the battery cell can disconnect the electrical connection between the first current collecting component and the shell after a short circuit occurs, and then cut off the short-circuit path, thereby alleviating damage to the information collection equipment and the like, and can effectively reduce the risk of further use caused by the battery cell, which is conducive to improving the reliability of the battery cell.

[0008] In some embodiments, the minimum flow area of ​​the connector is S1, which satisfies 2mm 2 ≤S1≤20mm 2 .

[0009] In the above technical solution, by setting the minimum flow area of ​​the connector to 2mm 2 Up to 20mm 2 On the one hand, the minimum flow area of ​​the connector is set to be greater than or equal to 2mm 2 , in order to improve the structural strength of the connector, thereby reducing the risk of accidental breakage of the connector during use, which is beneficial to improving the service life and stability of the battery cell. On the other hand, the minimum flow area of ​​the connector is set to be less than or equal to 20mm 2 , in order to alleviate the phenomenon that it takes too long for the connector to melt when a short circuit occurs in the battery cell, and make the connector easier to melt, so that the connector can be quickly melted when a short circuit occurs in the battery cell to cut off the short circuit path, thereby further alleviating the phenomenon of damage to the information collection equipment and helping to further improve the reliability of the battery cell. Therefore, the minimum flow area of ​​the connector is set to 2mm 2 Up to 20mm 2 , while ensuring that the connector has sufficient strength during use, it can also achieve rapid melting of the connector when a short circuit occurs in the battery cell.

[0010] In some embodiments, the connecting member and the first current collecting member are provided separately.

[0011] In the above technical solution, by setting the connecting member and the first current collecting member as a separate structure, on the one hand, it is convenient to separately process and form the connecting member and the first current collecting member, so that the production process of the connecting member and the first current collecting member can be carried out simultaneously, thereby optimizing the production rhythm of the battery cell, which is beneficial to improving the production efficiency of the battery cell. On the other hand, it is convenient to replace or maintain the connecting member during the use of the battery cell, which is beneficial to reducing the later maintenance cost of the battery cell.

[0012] In some embodiments, along the thickness direction of the wall portion, the first current collecting member is arranged between the main body and the wall portion, and the connecting member is an elastic member arranged between the first current collecting member and the wall portion, and the two ends of the connecting member are respectively abutted against the first current collecting member and the wall portion to electrically connect the first current collecting member and the wall portion.

[0013] In the above technical solution, the connecting member is provided as an elastic member located between the first current collecting member and the wall portion, and the two ends of the elastic member in the thickness direction of the wall portion are respectively abutted against the wall portion and the first current collecting member, thereby realizing that the connecting member electrically connects the first current collecting member and the wall portion. The structure is simple and easy to assemble.

[0014] In some embodiments, in the extension direction of the connector, part of the connector forms a weak section, and the housing is electrically connected to the first current collecting member through the weak section; wherein the minimum flow area of ​​the weak section is the minimum flow area S1 of the connector.

[0015] In the above technical solution, a weak section is formed in the part of the connector in its extension direction, so that the minimum flow area of ​​the weak section of the connector is the minimum flow area of ​​the connector, so that when a short circuit occurs in the battery cell, the weak section of the connector can be melted. On the one hand, by setting a weak section structure on the connector, the minimum flow area of ​​the connector can be smaller than the minimum flow area of ​​the first pole ear, the structure is simple and easy to manufacture. On the other hand, the melting position of the connector can be controlled, and the melting position can be controlled in the area where the weak section is located, so as to facilitate the assembly of the connector and avoid the weak section during the assembly process, which is conducive to reducing the difficulty of assembling the connector.

[0016] In some embodiments, along the extension direction of the connecting piece, the length of the weak section is L1, which satisfies 0.3 mm ≤ L1 ≤ 5 mm.

[0017] In the above technical solution, by setting the length of the weak section in the extension direction of the connector to 0.3mm to 5mm, on the one hand, the length of the weak section is set to be greater than or equal to 0.3mm, so that the connector has sufficient space to fuse when a short circuit occurs in the battery cell, thereby effectively reducing the phenomenon of incorrect overlap of the weak section of the connector after melting, so as to reduce the overlap risk of the connector after melting. On the other hand, the length of the weak section is set to be less than or equal to 5mm to alleviate the phenomenon of excessive space occupied by the weak section, thereby improving the internal space utilization rate of the battery cell. Therefore, setting the length of the weak section in the extension direction of the connector to 0.3mm to 5mm can not only reduce the risk of incorrect overlap after the weak section of the connector melts, but also effectively save the space occupied by the weak section of the connector.

[0018] In some embodiments, the connecting member further includes a first insulating member; the first insulating member is wrapped around the outer side of the weak section.

[0019] In the above technical solution, by covering the outside of the weak section of the connector with the first insulating member, on the one hand, the first insulating member can play a certain protective role on the weak section, so as to reduce the risk of the weak section being accidentally broken due to wear or collision, which is beneficial to improving the service life of the connector. On the other hand, since the connector is an elastic member and has a certain elastic force, the weak section of the connector can still play a certain insulating isolation role through the first insulating member after it melts when a short circuit occurs in the battery cell, so as to reduce the phenomenon that the weak section overlaps with the wall or the first current collecting component under the elastic force of the connector after the melting, thereby reducing the risk of the weak section of the connector overlapping with other components after the melting.

[0020] In some embodiments, the connecting member also includes a first connecting section, the minimum flow area of ​​the first connecting section is greater than the minimum flow area of ​​the weak section; wherein, along the thickness direction of the wall portion, the first connecting section is connected to one end of the weak section close to the wall portion, and the first connecting section abuts against the wall portion.

[0021] In the above technical solution, the connector is further provided with a first connecting section, so that the weak section of the connector is a structure in which the first connecting section and the wall portion abut against each other, and the minimum flow area of ​​the first connecting section is greater than the minimum flow area of ​​the weak section. Therefore, while the connector can be melted at the weak section, the stability and reliability of the mutual abutment between the connector and the wall portion can be improved through the structure in which the first connecting section and the wall portion abut against each other, which is beneficial to improving the flow area between the connector and the wall portion.

[0022] In some embodiments, the connecting member also includes a second connecting section, the minimum flow area of ​​the second connecting section is greater than the minimum flow area of ​​the weak section; wherein, along the thickness direction of the wall portion, the second connecting section is connected to one end of the weak section close to the first current collecting component, and the second connecting section abuts against the first current collecting component.

[0023] In the above technical solution, the connector is further provided with a second connecting section, so that the weak section of the connector is a structure in which the second connecting section abuts against the first current collecting component, and the minimum flow area of ​​the second connecting section is greater than the minimum flow area of ​​the weak section. Therefore, while the connector can be melted in the weak section, the stability and reliability of the mutual abutment between the connector and the first current collecting component can be improved through the structure in which the second connecting section abuts against the first current collecting component, which is conducive to improving the flow area between the connector and the first current collecting component.

[0024] In some embodiments, the connecting member is a spring, and along a thickness direction of the wall portion, two ends of the spring are respectively in contact with the first current collecting member and the wall portion.

[0025] In the above technical solution, by setting the connecting piece as a spring that abuts between the first current collecting component and the wall portion, the connecting piece with this structure is easy to assemble, which is beneficial to reducing the difficulty of assembling the connecting piece between the wall portion and the first current collecting component, and is beneficial to improving the structural stability of the connecting piece abutting between the wall portion and the first current collecting component, thereby improving the assembly stability of the connecting piece.

[0026] In some embodiments, along the thickness direction of the wall portion, a receiving portion is provided on a side of the wall portion facing the electrode assembly, and a portion of the connector is inserted into the receiving portion.

[0027] In the above technical solution, an accommodating portion for partially inserting the connector is provided on the side of the wall portion facing the electrode assembly, so that one end of the connector abutting the wall portion in the thickness direction of the wall portion can be inserted into the accommodating portion of the wall portion. Therefore, on the one hand, the accommodating portion can play a certain positioning role on the connector, which is beneficial to reducing the difficulty of assembling the connector between the wall portion and the first current collecting component, thereby improving the production efficiency of the battery cell, and is beneficial to improving the assembly accuracy of the connector between the wall portion and the first current collecting component. On the other hand, the accommodating portion can play a certain limiting role on the connector in the radial direction of the connector, which is beneficial to improving the structural stability of the connector assembled between the wall portion and the first current collecting component, thereby reducing the shaking of the connector during use.

[0028] In some embodiments, the side surface of the accommodating portion includes a limiting surface, and the limiting surface is configured to limit the connecting member from being separated from the accommodating portion along the thickness direction of the wall portion.

[0029] In the above technical solution, a limiting surface is formed on the side of the accommodating portion, and the limiting surface can limit the connection piece from being separated from the accommodating portion in the thickness direction of the wall portion, so as to further improve the structural stability of the connection piece assembled between the wall portion and the first current collecting component, thereby effectively reducing the phenomenon of the connection piece falling off during use, thereby reducing the risk of connection failure between the wall portion and the first current collecting component.

[0030] In some embodiments, the connecting member is a conical spring, the limiting surface is a conical surface that fits with the outer peripheral surface of the conical spring, and along the thickness direction of the wall portion, the large end of the limiting surface is farther away from the first current collecting component than the small end of the limiting surface.

[0031] In the above technical solution, the connecting member is set as a conical spring so that the connecting member is conical. Correspondingly, the limiting surface of the accommodating portion is set as a conical surface that fits with the outer peripheral surface of the connecting member, and the small end of the limiting surface is located between the large end of the limiting surface and the first collecting component in the thickness direction of the wall portion, so that after the connecting member is inserted into the accommodating portion, the limiting surface of the accommodating portion can play a limiting role on the connecting member to confine the connecting member in the accommodating portion. The structure is simple and easy to manufacture.

[0032] In some embodiments, the diameter of the large end of the limiting surface in the thickness direction of the wall portion is D1, and the diameter of the small end of the limiting surface in the thickness direction of the wall portion is D2, satisfying 0.5mm≤D1-D2≤5mm.

[0033] In the above technical solution, by setting the difference between the diameter of the large end of the limiting surface and the diameter of the small end of the limiting surface to be greater than or equal to 0.5mm, the limiting effect of the limiting surface on the connector is improved, thereby further reducing the phenomenon of the connector detaching from the accommodating portion along the thickness direction of the wall portion, so as to further reduce the risk of connection failure between the wall portion and the first current collecting component, and by setting the difference between the diameter of the large end of the limiting surface and the diameter of the small end of the limiting surface to be less than or equal to 5mm, the phenomenon of the difficulty of assembling the connector into the accommodating portion is alleviated, which is beneficial to reducing the difficulty of assembly between the connector and the wall portion. Therefore, setting the difference between the diameter of the large end of the limiting surface and the diameter of the small end of the limiting surface to 0.5mm to 5mm can not only achieve a better limiting effect of the limiting surface on the connector, but also reduce the difficulty of inserting the connector into the accommodating portion.

[0034] In some embodiments, along the thickness direction of the wall portion, the compression ratio of the connecting member is 10%-50%.

[0035] In the above technical solution, the compression ratio of the spring serving as the connecting member before assembly and after assembly between the wall portion and the first current collecting member is 10% to 50%. On the one hand, the compression ratio of the connecting member is set to be greater than or equal to 10% to enhance the effect of the connecting member abutting between the wall portion and the first current collecting member, and is beneficial to enhancing the structural stability of the connecting member when assembled between the wall portion and the first current collecting member. On the other hand, the compression ratio of the connecting member is set to be less than or equal to 50% to alleviate the phenomenon of plastic deformation caused by excessive compression of the connecting member, thereby benefiting to improving the service life of the connecting member. Therefore, the compression ratio of the connecting member is set to 10% to 50%, which can take into account the better abutment effect of the connecting member with the wall portion and the first current collecting member, while also alleviating the phenomenon that the connecting member cannot recover elastic deformation due to excessive compression.

[0036] In some embodiments, the connecting piece is integrally formed with the first current collecting member.

[0037] In the above technical solution, by setting the connecting piece and the first current collecting member as an integrally formed structure, it is beneficial to improve the connection stability and reliability between the connecting piece and the first current collecting member, so as to reduce the risk of connection failure between the connecting piece and the first current collecting member, and the connecting piece and the first current collecting member can be assembled in the outer shell at the same time, which is beneficial to optimize the production rhythm of the battery cell and improve the production efficiency of the battery cell.

[0038] In some embodiments, the first current collecting member is arranged between the main body and the wall portion along the thickness direction of the wall portion; wherein, the first current collecting member and the connecting member are arranged along a first direction, the first direction is perpendicular to the thickness direction of the wall portion, and along the first direction, a portion of the connecting member forms a weak section, the weak section is connected to the first current collecting member, and the minimum flow area of ​​the weak section is the minimum flow area S1 of the connecting member.

[0039] In the above technical solution, the first current collecting member and the connector are arranged in a first direction, and the portion of the connector in the first direction forms a weak section connected to the first current collecting member, so that the minimum flow area of ​​the weak section of the connector is the minimum flow area of ​​the connector, so that when a short circuit occurs in the battery cell, the weak section of the connector can be melted. On the one hand, the structure in which the weak section of the connector is connected to the first current collecting member can achieve a minimum flow area of ​​the connector that is smaller than the minimum flow area of ​​the first tab, and facilitates the manufacturing and molding of the first current collecting member and the connector, has a simple structure, and is easy to manufacture. On the other hand, the melting position of the connector can be controlled, and the melting position can be controlled to the part where the weak section is located, so as to facilitate the assembly of the connector and avoid the weak section during the assembly process, which is conducive to reducing the difficulty of assembling the connector.

[0040] In some embodiments, along the first direction, the length of the weak section is L2, satisfying 0.3 mm ≤ L2 ≤ 5 mm.

[0041] In the above technical solution, by setting the length of the weak section in the first direction to 0.3mm to 5mm, that is, the length of the weak section in the extension direction of the connector is 0.3mm to 5mm, on the one hand, the length of the weak section is set to be greater than or equal to 0.3mm, so that the connector has sufficient space to fuse when a short circuit occurs in the battery cell, thereby effectively reducing the phenomenon of incorrect overlapping of the weak section of the connector after melting, so as to reduce the overlapping risk of the connector after melting. On the other hand, the length of the weak section is set to be less than or equal to 5mm to alleviate the phenomenon of excessive space occupied by the weak section in the first direction, thereby improving the internal space utilization of the battery cell. Therefore, setting the length of the weak section in the first direction to 0.3mm to 5mm can not only reduce the risk of incorrect overlapping of the weak section of the connector after melting, but also effectively save the space occupied by the weak section of the connector in the first direction.

[0042] In some embodiments, the connecting member also includes a first connecting section, the minimum flow area of ​​the first connecting section is greater than the minimum flow area of ​​the weak section, the first connecting section is connected to the wall portion, the weak section connects the first connecting section and the first current collecting component, and the first current collecting component, the weak section and the first connecting section are arranged along the first direction.

[0043] In the above technical solution, the connector is further provided with a first connecting section, so that the weak section of the connector is a structure interconnected with the wall portion through the first connecting section, so that the first current collecting component, the weak section, the first connecting section and the wall portion are structures connected in sequence, and the minimum flow area of ​​the first connecting section is greater than the minimum flow area of ​​the weak section, so that while the connector can be melted in the weak section, the connection area and connection reliability between the connector and the wall portion can be improved through the structure interconnected with the first connecting section and the wall portion, which is beneficial to improving the flow area between the connector and the wall portion.

[0044] In some embodiments, the first connecting section includes a first connecting portion, a bending portion, and a second connecting portion connected in sequence, the first connecting portion is connected to the weak section, and the second connecting portion is connected to the wall portion; wherein, along the thickness direction of the wall portion, the second connecting portion is closer to the wall portion than the first connecting portion, and the second connecting portion abuts against the wall portion.

[0045] In the above technical solution, the first connecting section is provided with a first connecting portion, a bending portion and a second connecting portion connected in sequence. The first connecting portion is connected to the first current collecting component through a weak section, and the second connecting portion is connected to the wall portion, so as to realize electrical connection between the wall portion and the first current collecting component through the connecting member. The second connecting portion is arranged closer to the wall portion than the first connecting portion in the thickness direction of the wall portion, so that the first connecting section is a "Z"-shaped structure. The first connecting section of this structure can compensate for the gap between the first current collecting component and the wall portion in the thickness direction of the wall portion. On the one hand, it can improve the connection stability and connection reliability between the first connecting section of the connecting member and the wall portion, which is conducive to improving the assembly quality between the connecting member and the wall portion. On the other hand, there is no need to set other components to compensate for the gap between the first current collecting component and the wall portion in the thickness direction of the wall portion, which is conducive to reducing the assembly difficulty between the connecting member and the wall portion, thereby improving the production efficiency of the battery cell.

[0046] In some embodiments, along a thickness direction of the wall portion, the first connection portion has a first surface facing the wall portion, and the first current collecting member has a second surface facing the wall portion, wherein the second surface is flush with the first surface.

[0047] In the above technical solution, by setting the first surface of the first connecting portion facing the wall portion and the second surface of the first current collecting member facing the wall portion to be flush with each other, on the one hand, the shape regularity and flatness between the first connecting portion and the first current collecting member can be improved, which is conducive to reducing the difficulty of assembling the first current collecting member and the connecting piece into the outer shell, and can make the first current collecting member and the first connecting portion share part of the space in the thickness direction of the wall portion, which is conducive to improving the internal space utilization rate of the battery cell. On the other hand, it is convenient to integrally form the first current collecting member and the first connecting portion through the same plate material, and it is convenient to form a weak section between the first current collecting member and the first connecting portion, which is conducive to reducing the manufacturing difficulty of the integrally formed first current collecting member and the first connecting portion.

[0048] In some embodiments, along a thickness direction of the wall portion, the first connection portion has a third surface facing away from the wall portion, and the first current collecting member has a fourth surface facing away from the wall portion, wherein the fourth surface is flush with the third surface.

[0049] In the above technical solution, by setting the third surface of the first connecting portion away from the wall portion and the fourth surface of the first current collecting member away from the wall portion to a structure that is flush with each other, on the one hand, the shape regularity and flatness between the first connecting portion and the first current collecting member can be improved, which is conducive to reducing the difficulty of assembling the first current collecting member and the connecting piece into the outer shell, and can make the first current collecting member and the first connecting portion share part of the space in the thickness direction of the wall portion, which is conducive to improving the internal space utilization rate of the battery cell. On the other hand, it is convenient to integrally form the first current collecting member and the first connecting portion through the same plate material, and it is convenient to form a weak section between the first current collecting member and the first connecting portion, which is conducive to reducing the manufacturing difficulty of the integrally formed first current collecting member and the first connecting portion.

[0050] In some embodiments, the second connecting portion is connected to the wall portion by welding.

[0051] In the above technical solution, a welding connection structure is used to connect the second connection portion of the first connection and the wall portion, which is beneficial to improving the connection reliability and connection stability between the connector and the wall portion, thereby reducing the phenomenon of failure of the connection between the connector and the wall portion due to accidental detachment of the connector and the wall portion during the use of the battery cell.

[0052] In some embodiments, the welding area between the second connecting portion and the wall portion is S2, which satisfies 30 mm 2 ≤S2≤100mm 2 .

[0053] In the above technical solution, by setting the welding area between the second connecting portion of the first connecting section and the wall portion to 30mm 2 Up to 100mm 2 On the one hand, the welding area between the second connecting part and the wall is set to be greater than or equal to 30mm 2 , in order to improve the welding effect between the second connecting part and the wall, thereby improving the connection reliability and connection stability between the connecting part and the wall. On the other hand, the welding area between the second connecting part and the wall is set to be less than or equal to 100mm 2 , in order to reduce the welding difficulty between the second connecting part and the wall part, and to reduce the welding power required for welding the second connecting part and the wall part to each other, thereby effectively reducing the assembly difficulty between the connecting part and the wall part, which is beneficial to improving the production efficiency of the battery monomer and reducing the production cost of the battery monomer. Therefore, the welding area between the second connecting part and the wall is set to 30mm 2 Up to 100mm 2 , while taking into account the welding quality between the connecting piece and the wall portion, it can also effectively reduce the difficulty of welding and assembling between the connecting piece and the wall portion.

[0054] In some embodiments, a groove is formed between the first current collecting member and the first connecting section along the first direction, and a bottom wall of the groove serves as the weak section.

[0055] In the above technical solution, a groove is formed between the first current collecting member and the first connecting section of the connecting member, so that the area corresponding to the bottom wall of the groove becomes the weak section of the connecting member, so that the first current collecting member and the connecting member can be formed as an integral part by processing the groove structure on a plate, and a weak section connected to the first current collecting member is formed on the connecting member. The structure is simple and easy to process and form.

[0056] In some embodiments, the groove is formed on at least one side of the weak section along the second direction, and the first direction, the second direction, and the thickness direction of the wall portion are perpendicular to each other.

[0057] In the above technical solution, a groove is formed on at least one side of the weak section along the second direction, so that the groove is located on one side of the weak section in the second direction, thereby forming a weak section on the bottom wall of the groove. The structure is simple and easy to process.

[0058] In some embodiments, the groove is formed on at least one side of the weak section along the thickness direction of the wall portion.

[0059] In the above technical solution, a groove is formed on at least one side of the weak section in the thickness direction of the wall portion, so that the groove is located on one side of the weak section in the thickness direction of the wall portion to form a weak section on the bottom wall of the groove. The structure is simple and easy to process.

[0060] In some embodiments, the first tab is a positive tab of the electrode assembly.

[0061] In the above technical solution, by setting the first pole ear as the positive pole ear of the electrode assembly, the first pole ear is used to output or input the positive electrode of the electrode assembly. Correspondingly, the connecting piece is used to output the positive electrode of the electrode assembly, so that the wall portion is a positively charged structure when the information acquisition device performs data acquisition. The battery cell using this structure can effectively alleviate the phenomenon of electrical corrosion on the outer shell of the battery cell, thereby helping to improve the service life of the battery cell and reducing the risk of leakage of the battery cell during use.

[0062] In some embodiments, the first electrode terminal is insulated and mounted on the wall portion, the first current collecting member is disposed between the main body and the wall portion along a thickness direction of the wall portion, and the first electrode tab is disposed at one end of the main body facing the wall portion.

[0063] In the above technical solution, the first electrode terminal is insulated and installed on the wall portion, and the first pole lug is arranged at one end of the main body facing the wall portion in the thickness direction of the wall portion, so that the first electrode terminal, the first current collecting member and the first pole lug are all located on the side of the main body facing the wall portion in the thickness direction of the wall portion. On the one hand, the difficulty of assembling the first pole lug and the first current collecting member can be reduced, and the difficulty of assembling the first current collecting member and the first electrode terminal can be reduced, which is beneficial to improving the production efficiency of the battery cell. On the other hand, there is no need to excessively extend the first pole lug or the first current collecting member, thereby reducing the risk of overlap between the first pole lug or the first current collecting member and other components.

[0064] In some embodiments, the battery cell further includes a second electrode terminal and a second current collecting member, the second electrode terminal is insulated and mounted on the outer shell, and the second current collecting member is disposed within the outer shell; wherein the electrode assembly further includes a second pole tab, the second pole tab is disposed on the main body, the second pole tab has an opposite polarity to the first pole tab, and the second pole tab is electrically connected to the second electrode terminal through the second current collecting member.

[0065] In the above technical solution, the battery cell is also provided with a second electrode terminal and a second current collecting member. Correspondingly, the electrode assembly also includes a second pole ear, the polarity of the second pole ear is opposite to that of the first pole ear, and the second pole ear is connected to the second electrode terminal through the second current collecting member, so that the first electrode terminal and the second electrode terminal cooperate to input or output the positive and negative electrodes of the battery cell, wherein, by insulating the second electrode terminal and installing it on the outer casing, it is helpful to reduce the risk of short circuit between the second electrode terminal and the connector.

[0066] In some embodiments, the housing includes a shell and an end cover; a receiving cavity with an opening is formed inside the shell, and the receiving cavity is used to receive the electrode assembly; the end cover closes the opening; wherein the end cover is the wall portion.

[0067] In the above technical solution, by setting the wall portion of the shell as the end cover for closing the opening of the shell, the battery cell adopting this structure facilitates the connection of the connector to the wall portion of the shell, which is beneficial to reducing the difficulty of assembling the battery cell and improving the production efficiency of the battery cell.

[0068] In some embodiments, the outer shell includes a shell and an end cover; the shell includes an integrally formed side wall and the wall portion, the side wall is arranged around the wall portion, and along the thickness direction of the wall portion, one end of the side wall is connected to the wall portion, and the other end is enclosed to form an opening, and the side wall and the wall portion jointly define a accommodating cavity for accommodating the electrode assembly; the end cover closes the opening.

[0069] In the above technical solution, by setting the wall portion of the outer shell as a wall arranged opposite to the end cover in the thickness direction of the wall portion of the shell, the battery cell adopting this structure can make the wall portion used for connecting to the connector away from the end cover, so that there is no direct connection relationship between the wall portion and the end cover, thereby alleviating the influence of the stress generated by the mutual assembly between the end cover and the shell on the connector, which is beneficial to improving the service life of the connector, and can alleviate the phenomenon that the force generated by other components pulling or twisting the wall portion acts on the end cover, so as to reduce the risk of connection failure between the end cover and the shell, and further help to further reduce the risk of leakage of the battery cell during use.

[0070] In a second aspect, an embodiment of the present application further provides a battery comprising the above-mentioned battery cell.

[0071] In some embodiments, the battery further includes a battery management system; the battery management system is electrically connected to the wall portion, and the battery management system is configured to issue an early warning when the connection member is fused.

[0072] In the above technical solution, the battery is also provided with a battery management system, which is electrically connected to the wall, and the battery management system can issue an early warning after a short circuit occurs in the battery cell and causes the connector to melt, so as to provide an early warning to the operator or user, thereby reducing the further damage or impact caused by the short circuit of the battery cell to the operator or user, which is conducive to improving the reliability of the battery.

[0073] In a third aspect, an embodiment of the present application further provides an electrical device comprising the above-mentioned battery cell, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0075] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0076] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0077] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0078] FIG4 is an exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0079] FIG5 is a cross-sectional view of a battery cell provided in some embodiments of the present application;

[0080] FIG6 is a partial enlarged view of the battery cell at point A shown in FIG5 ;

[0081] FIG7 is a cross-sectional view of a connector of a battery cell provided in some embodiments of the present application;

[0082] FIG8 is a partial enlarged view of point B of the connector shown in FIG7 ;

[0083] FIG9 is a partial cross-sectional view of a connector of a battery cell provided by some embodiments of the present application in another embodiment;

[0084] FIG10 is a schematic diagram of the assembly of a wall portion and a connector of a battery cell provided in some embodiments of the present application;

[0085] FIG11 is a partial cross-sectional view of a wall portion of a battery cell provided in some embodiments of the present application;

[0086] FIG12 is an exploded view of the structure of a battery cell provided in some other embodiments of the present application;

[0087] FIG13 is a cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0088] FIG14 is a partial enlarged view of a portion C of the battery cell shown in FIG12 ;

[0089] FIG15 is a schematic diagram showing the connection between a connector of a battery cell and a first current collecting member according to some other embodiments of the present application;

[0090] FIG16 is a cross-sectional view of a battery cell connector connected to a first current collecting member according to yet other embodiments of the present application;

[0091] FIG17 is a schematic diagram showing the connection between the connector of the battery cell and the first current collecting member in other embodiments provided by still other embodiments of the present application;

[0092] FIG18 is a cross-sectional view of a battery cell connector connected to a first current collecting member in other embodiments provided by still other embodiments of the present application.

[0093] Icons: 1000-vehicle; 100-battery; 10-housing; 11-first housing; 12-second housing; 20-battery cell; 21-housing; 211-wall; 2111-accommodation; 2111a-limiting surface; 212-housing; 2121-opening; 213-end cover; 22-first electrode terminal; 23-electrode assembly; 231-main body; 232-first electrode tab; 233-second electrode tab; 24-first current collecting member; 241-first protrusion; 242-second surface; 243-fourth surface; 25-connector; 25 1-weak section; 252-first insulating member; 253-first connecting section; 2531-first connecting portion; 2531a-first surface; 2531b-third surface; 2532-bending portion; 2533-second connecting portion; 254-second connecting section; 255-groove; 26-second electrode terminal; 27-second current collecting member; 271-second protrusion; 28-second insulating member; 281-avoidance hole; 29-pressure relief mechanism; 30-weld stamp; 200-controller; 300-motor; X-thickness direction of the wall; Y-first direction; Z-second direction. DETAILED DESCRIPTION

[0094] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0095] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0096] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0097] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0098] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0099] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0100] The term "plurality" used in this application refers to two or more (including two).

[0101] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0102] The battery cells can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., which are not limited in the embodiments of the present application.

[0103] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0104] 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.

[0105] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0106] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, 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. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may 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.).

[0107] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional 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. Among them, examples of lithium-containing phosphates may include but are not limited to at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides 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, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05O2) and at least one of its modified compounds, etc.

[0108] In some embodiments, a positive electrode may utilize a metal foam. The metal foam may include nickel foam, copper foam, aluminum foam, alloy foam, or the like. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not include a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled or / and deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0109] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0110] As an example, the negative electrode current collector may be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, or titanium, etc. may be used. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, etc. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may 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.).

[0111] 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.

[0112] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0113] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells that is well known in the art. 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, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0114] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0115] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0116] In some embodiments, the separator is a separator membrane. There are many types of separator membranes, and any known separator membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0117] As an example, the separator can be made of at least one of fiberglass, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film. In the case of a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a separate component positioned between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0118] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0119] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0120] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium bisoxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0121] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0122] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0123] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0124] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, or the like.

[0125] As an example, the inorganic solid electrolyte may include an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0126] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0127] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0128] In some embodiments, the electrode assembly is a laminate structure.

[0129] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0130] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0131] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0132] As an example, a plurality of separators may be provided, each of which is disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0133] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0134] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0135] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0136] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0137] As an example, the battery cells may be cylindrical, prismatic, soft-pack or other shaped battery cells. Prismatic battery cells include but are not limited to square-shell, blade-shaped, and polygonal batteries, such as hexagonal batteries.

[0138] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0139] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0140] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are housed in the case.

[0141] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0142] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0143] Batteries, with their outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient, are a vital component of today's new energy development. The development of battery technology requires simultaneous consideration of multiple design factors, including performance parameters such as energy density, cycle life, discharge capacity, and charge / discharge rate. Furthermore, battery safety must also be considered.

[0144] A typical battery cell typically includes a housing, an electrode assembly, two electrode terminals, and two current collecting members. The electrode assembly is housed within the housing, and the two electrode terminals are disposed on the housing. The two electrode terminals are connected to the positive and negative tabs of the electrode assembly, respectively, via two current collecting members, to enable input or output of the positive and negative electrodes of the battery cell. By connecting an information collection device to the electrode terminals, the battery cell's usage can be monitored. To reduce the difficulty of connecting the information collection device to the battery cell and thus the difficulty of data collection, in related art, the battery cell housing is connected to a tab of the electrode assembly via a current collecting member, so that the battery cell housing carries a positive or negative charge. Thus, by connecting the information collection device to the battery cell housing, battery cell usage information can be collected, which helps reduce the difficulty of assembling and arranging the information collection device. However, battery cells with this structure are prone to overlapping tabs of different polarities and the housing, creating the risk of overlapping short circuits in the battery cell, which in turn can easily damage the information collection device. This also poses a greater risk of battery cell usage, hindering the reliability of the battery cell.

[0145] Based on the above considerations, and in order to address the issue of low reliability in the use of battery cells, an embodiment of the present application provides a battery cell, comprising a housing, a first electrode terminal, an electrode assembly, a first current collecting member, and a connector. The housing has a wall portion. The first electrode terminal is insulated and mounted to the housing. The electrode assembly is housed within the housing, and the electrode assembly comprises a main body portion and a first tab, the first tab being disposed on the main body portion. A first current collecting member is disposed within the housing, and the first current collecting member is electrically connected to the first electrode terminal and the first tab. The connector electrically connects the wall portion and the first current collecting member, and the minimum flow area of ​​the connector is smaller than the minimum flow area of ​​the first current collecting member.

[0146] In a battery cell of this structure, a connector is further provided in the battery cell, and the first current collecting member and the wall of the shell are connected by the connector, so that the positive electrode or the negative electrode of the electrode assembly can be electrically connected to the shell, so that the information collection device can collect the usage information of the battery cell after being electrically connected to the shell, thereby facilitating the information collection device to connect the battery cell and collect data, which is conducive to reducing the difficulty of data collection of the battery cell, wherein, by setting the minimum flow area of ​​the connector to be smaller than the minimum flow area of ​​the first current collecting member, so that the minimum cross-sectional area of ​​the connector on the path for current to pass is smaller than the minimum cross-sectional area of ​​the first current collecting member on the path for current to pass, The resistance of the connector at the minimum flow area is greater than the resistance of the first current collecting component. Therefore, within the same time, the heat generated by the connector when the electrode assembly inside the battery cell and the shell overlap and short-circuit occurs is higher and the heat accumulates faster, so that the connector can be melted preferentially compared to the first current collecting component when the electrode assembly inside the battery cell and the shell overlap and short-circuit occurs, so that the battery cell can disconnect the electrical connection between the first current collecting component and the shell after a short circuit occurs, and then cut off the short-circuit path, thereby alleviating damage to the information collection equipment and the like, and can effectively reduce the risk of further use caused by the battery cell, which is conducive to improving the reliability of the battery cell.

[0147] The battery cells disclosed in the embodiments of this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power supply system comprising the battery cells and batteries disclosed in this application can be used to construct such electrical devices. This helps mitigate the risks of internal short circuits in the battery cells, thereby improving the reliability of the battery cells.

[0148] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0149] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0150] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000. The battery 100 can be arranged at the bottom of the vehicle 1000, or at the head of the vehicle 1000, or at the tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can be used as an operating power source or a power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0151] In some embodiments of the present application, the battery 100 can not only serve as the operating power source or usage power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0152] 2 and 3 , FIG2 is an exploded view of a battery 100 according to some embodiments of the present invention, and FIG3 is a schematic diagram of a battery cell 20 according to some embodiments of the present invention. The battery 100 includes a housing 10 and a battery cell 20 , wherein the battery cell 20 is accommodated in the housing 10 .

[0153] The housing 10 is used to provide assembly space for the battery cells 20 and can adopt a variety of structures. In some embodiments, the housing 10 can include a first housing body 11 and a second housing body 12. The first housing body 11 and the second housing body 12 cover each other, and the first housing body 11 and the second housing body 12 jointly define an assembly space for accommodating the battery cells 20. The second housing body 12 can be a hollow structure with one end open, and the first housing body 11 can be a plate-like structure. The first housing body 11 covers the open side of the second housing body 12, so that the first housing body 11 and the second housing body 12 jointly define the assembly space. The first housing body 11 and the second housing body 12 can also be hollow structures with one end open, and the open side of the first housing body 11 covers the open side of the second housing body 12.

[0154] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cuboid or a cube, etc. For example, in FIG2 , the box body 10 is in the shape of a cuboid.

[0155] In the battery 100, there can be one or more battery cells 20 disposed within the housing 10. When there are multiple battery cells 20 disposed within the housing 10, the multiple battery cells 20 can be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel configurations within the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure formed by the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery 100 can be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid configuration to form a battery module, which is then further connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 10.

[0156] In some embodiments, the battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which is used to connect the multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20 .

[0157] Each 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 thereto. The battery cell 20 can be a rectangular parallelepiped, a cylinder, a prism, or other shapes. For example, in FIG3 , the battery cell 20 is a rectangular parallelepiped.

[0158] According to some embodiments of the present application, referring to FIG3 and further to FIG4, FIG5, and FIG6, FIG4 is an exploded view of a battery cell 20 according to some embodiments of the present application, FIG5 is a cross-sectional view of a battery cell 20 according to some embodiments of the present application, and FIG6 is a partial enlarged view of a portion A of the battery cell 20 shown in FIG5. The present application provides a battery cell 20, comprising a housing 21, a first electrode terminal 22, an electrode assembly 23, a first current collecting member 24, and a connector 25. The housing 21 has a wall 211. The first electrode terminal 22 is insulated and mounted to the housing 21. The electrode assembly 23 is housed within the housing 21 and includes a main body 231 and a first electrode tab 232, the first electrode tab 232 being disposed on the main body 231. The first current collecting member 24 is disposed within the housing 21 and electrically connects the first electrode terminal 22 and the first electrode tab 232. The connecting member 25 electrically connects the wall portion 211 and the first current collecting member 24 , and a minimum flow area of ​​the connecting member 25 is smaller than a minimum flow area of ​​the first current collecting member 24 .

[0159] The housing 21 can also be used to accommodate an electrolyte, such as an electrolyte solution. The housing 21 can have various structural forms. The housing 21 can also be made of various materials, such as copper, iron, aluminum, steel, and aluminum alloys.

[0160] In some embodiments, the housing 21 may include a shell 212 and an end cover 213, wherein a accommodating cavity is formed inside the shell 212, and the accommodating cavity has an opening 2121, that is, the shell 212 is a hollow structure with one end open, and the end cover 213 covers the 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.

[0161] Optionally, the wall portion 211 for connecting to the connector 25 may be the end cap 213, or may be one of the multiple walls of the housing 212. For example, in Figures 3 and 4, the wall portion 211 is the end cap 213 of the housing 21. Of course, in other embodiments, the wall portion 211 may also be the bottom wall of the housing 212 that is opposite to the end cap 213 in the thickness direction X of the wall portion, or a side wall that is adjacent to and abuts against the end cap 213.

[0162] When assembling the battery cell 20 , the electrode assembly 23 may be placed in the housing 212 , and the housing 212 may be filled with electrolyte. The end cap 213 may then be placed on the opening 2121 of the housing 212 to seal the opening 2121 of the housing 212 .

[0163] Optionally, the housing 212 can have a variety of shapes, such as a cylinder, a rectangular parallelepiped, etc. The shape of the housing 212 can be determined based on the specific shape of the electrode assembly 23. For example, if the electrode assembly 23 has a cylindrical structure, the housing 212 can have a cylindrical structure; if the electrode assembly 23 has a rectangular parallelepiped structure, the housing 212 can have a rectangular parallelepiped structure. Of course, the end cap 213 can also have a variety of structures, such as a plate-like structure or a hollow structure with one end open. For example, in Figure 4, the housing 212 has a rectangular parallelepiped structure and the end cap 213 has a plate-like structure.

[0164] It is understandable that the outer shell 21 is not limited to the above structure. The outer shell 21 may also be other structures. For example, the outer shell 21 includes a shell body 212 and two end covers 213. The shell body 212 is a hollow structure with openings 2121 on opposite sides. One end cover 213 corresponds to an opening 2121 of the shell body 212 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte.

[0165] The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. The structure of the electrode assembly 23 can be various. For example, the electrode assembly 23 can be a wound structure formed by winding the positive electrode sheet, the separator and the negative electrode sheet, or it can be a stacked structure formed by stacking the positive electrode sheet, the separator and the negative electrode sheet.

[0166] Illustratively, the separator is an isolation membrane, and a main material of the isolation membrane may be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

[0167] The electrode assembly 23 includes a main body 231 and a first tab 232. The first tab 232 is disposed on the main body 231. The main body 231 is the primary portion of the electrode assembly 23 where the electrochemical reaction occurs within the battery cell 20. The first tab 232 serves as the input or output for the positive or negative electrode of the electrode assembly 23. The first tab 232 is electrically connected to the first electrode terminal 22 to establish an electrical connection between the electrode assembly 23 and the first electrode terminal 22. It should be noted that the first tab 232 of the electrode assembly 23 is formed by laminating and connecting the regions of the positive electrode sheet not coated with the positive electrode active material layer, or by laminating and connecting the regions of the negative electrode sheet not coated with the negative electrode active material layer. If the first pole tab 232 is used to output the positive electrode of the electrode assembly 23, that is, the first pole tab 232 is the positive pole tab of the electrode assembly 23, then the first pole tab 232 is a component formed by mutually stacking and connecting the areas on the positive electrode sheet that are not coated with the positive electrode active material layer; if the first pole tab 232 is used to output the negative electrode of the electrode assembly 23, that is, the first pole tab 232 is the negative pole tab of the electrode assembly 23, then the first pole tab 232 is a component formed by mutually stacking and connecting the areas on the negative electrode sheet that are not coated with the negative electrode active material layer.

[0168] Optionally, the number of electrode assemblies 23 housed within the housing 21 may be one or more. For example, in FIG4 , the housing 21 of the battery cell 20 is provided with two electrode assemblies 23 , which are stacked along the second direction Z. The first direction Y, the second direction Z, and the thickness direction X of the wall portion are perpendicular to each other. The first direction Y is the length direction of the battery cell 20, the second direction Z is the thickness direction of the battery cell 20, and the thickness direction X of the wall portion is the height direction of the battery cell 20. Of course, in other embodiments, the number of electrode assemblies 23 housed within the housing 21 may be one, three, four, five, six, seven, or eight, etc.

[0169] In the embodiment of the present application, the first electrode terminal 22 plays the role of outputting or inputting electrical energy of the battery cell 20. One end of the first electrode terminal 22 is used to be electrically connected to the first electrode ear 232 of the electrode assembly 23, and the other end is used to be connected to the busbar component to realize the input or output of electrical energy of the battery cell 20.

[0170] Optionally, the connection structure between the first electrode terminal 22 and the first electrode tab 232 can be various. The first electrode terminal 22 can be directly connected to the first electrode tab 232, for example, the first electrode terminal 22 and the first electrode tab 232 are welded or abutted, etc. Of course, the first electrode terminal 22 can also be indirectly connected to the first electrode tab 232, for example, the first electrode terminal 22 is welded or abutted with other components and then connected to the first electrode tab 232. For example, in the embodiment of the present application, the first electrode tab 232 is electrically connected to the first electrode terminal 22 through the first current collecting member 24.

[0171] It should be noted that the first electrode terminal 22 is insulated and mounted on the outer shell 21. In other words, there is no electrical connection between the first electrode terminal 22 and the outer shell 21. The first electrode terminal 22 can be provided on the outer shell 21 in various structures. The first electrode terminal 22 can be mounted on the end cap 213 or on the housing 212. For example, in Figures 3 and 4, the first electrode terminal 22 is insulated and mounted on the end cap 213, that is, the first electrode terminal 22 is insulated and mounted on the wall 211 of the outer shell 21.

[0172] For example, the first electrode terminal 22 may be made of various materials. For example, the first electrode terminal 22 may be made of copper, iron, aluminum, steel, or aluminum alloy.

[0173] In the embodiment of the present application, the first current collecting member 24 serves to connect the first electrode terminal 22 and the first electrode tab 232 of the electrode assembly 23 , thereby achieving electrical connection between the electrode assembly 23 and the first electrode terminal 22 .

[0174] 4 and 5 , the first current collecting member 24 is disposed between the wall portion 211 and the body portion 231 along the thickness direction X of the wall portion so that the first current collecting member 24 connects the first electrode terminal 22 and the first tab 232 of the electrode assembly 23 .

[0175] 4 , the first current collecting member 24 is provided with a first protrusion 241 on one side facing the wall portion 211 in the thickness direction X of the wall portion. The first protrusion 241 is used to be connected to the first electrode terminal 22 to electrically connect the first current collecting member 24 and the first electrode terminal 22. The first current collecting member 24 with such a structure is conducive to reducing the difficulty of connecting the first current collecting member 24 and the first electrode terminal 22.

[0176] Illustratively, the first protrusion 241 of the first current collecting member 24 is welded to the first electrode terminal 22, and the first current collecting member 24 is welded to the first electrode tab 232. Of course, in other embodiments, the first protrusion 241 of the first current collecting member 24 may also be in abutment with the first electrode terminal 22, and similarly, the first current collecting member 24 may also be in abutment with the first electrode tab 232.

[0177] For example, the first current collecting member 24 may be made of various materials. For example, the first current collecting member 24 may be made of copper, iron, aluminum, steel, aluminum alloy, and the like.

[0178] In Figure 4, the battery cell 20 may also include a second electrode terminal 26 and a second current collecting member 27. The second electrode terminal 26 is insulated and installed on the outer shell 21. The second current collecting member 27 is arranged between the main body 231 and the wall portion 211 along the thickness direction X of the wall portion. Correspondingly, the electrode assembly 23 also includes a second pole tab 233. The second pole tab 233 is arranged on the main body 231, and the polarity of the second pole tab 233 is opposite to the polarity of the first pole tab 232. The second pole tab 233 is connected to the second electrode terminal 26 through the second current collecting member 27 to realize the input or output of the positive and negative poles of the battery cell 20.

[0179] Among them, the structure of the second electrode terminal 26 set on the outer shell 21 can be various. The second electrode terminal 26 can be installed on the end cover 213 or on the shell 212. For example, in Figures 3 and 4, the second electrode terminal 26 is insulated and installed on the end cover 213, that is, the second electrode terminal 26 is insulated and installed on the wall 211 of the outer shell 21.

[0180] Exemplarily, the first electrode tab 232 and the second electrode tab 233 are both arranged at one end of the main body 231 facing the end cover 213 in the thickness direction X of the wall portion, and the first electrode tab 232 and the second electrode tab 233 are arranged at intervals along the first direction Y, so that the first electrode tab 232 and the second electrode tab 233 are connected to the first electrode terminal 22 and the second electrode terminal 26 respectively through the first current collecting member 24 and the second current collecting member 27.

[0181] Optionally, as shown in Figure 4, the second current collecting member 27 is provided with a second protrusion 271 on the side facing the wall portion 211 in the thickness direction X of the wall portion. The second protrusion 271 is used to be connected to the second electrode terminal 26 to electrically connect the second current collecting member 27 and the second electrode terminal 26. The second current collecting member 27 with this structure is conducive to reducing the difficulty of connecting the second current collecting member 27 and the second electrode terminal 26.

[0182] Illustratively, the second protrusion 271 of the second current collecting member 27 is welded to the second electrode terminal 26, and the second current collecting member 27 is welded to the second electrode tab 233. Of course, in other embodiments, the second protrusion 271 of the second current collecting member 27 may also be in abutment with the second electrode terminal 26, and similarly, the second current collecting member 27 may also be in abutment with the second electrode tab 233.

[0183] The connector 25 connects the first current collecting member 24 and the wall portion 211, ensuring that the wall portion 211 of the battery cell 20 carries the same charge as the first tab 232. This facilitates the acquisition of usage information of the battery cell 20 by the information acquisition device after it is connected to the housing 21. It should be noted that when the information acquisition device needs to collect data on the usage of the battery cell 20, the two input terminals of the information acquisition device are respectively connected to the wall portion 211 of the housing 21 and the second electrode terminal 26 to collect usage data of the battery cell 20.

[0184] The connection structure between the connector 25 and the wall portion 211 can be various. For example, the connector 25 can be connected to the wall portion 211 by welding, abutting, or other structures. Similarly, the connection structure between the connector 25 and the first current collecting member 24 can also be various. For example, in Figures 4 and 6, the connector 25 and the first current collecting member 24 are separately arranged structures, that is, the connector 25 and the first current collecting member 24 are separate structures, and the connector 25 can be connected to the first current collecting member 24 by welding, abutting, or other structures. Of course, in other embodiments, the connector 25 and the first current collecting member 24 can also be an integrally formed structure, that is, the connector 25 and the first current collecting member 24 are an integral structure, and the connector 25 and the first current collecting member 24 can be made by an integral forming process such as stamping or casting.

[0185] The minimum flow area of ​​the connector 25 refers to the minimum cross-sectional area of ​​the connector 25 for current to pass through on the flow path of the current flowing from the first current collecting member 24 through the connector 25 to the wall portion 211 or from the wall portion 211 through the connector 25 to the first current collecting member 24. That is, in the direction in which the current flows through the connector 25, the area of ​​the minimum cross-section of the connector 25 perpendicular to the direction of current flow is the minimum flow area of ​​the connector 25.

[0186] Among them, the position of the minimum flow area of ​​the connector 25 can be determined by tomography, that is, the position of the minimum cross-section of the connector 25 perpendicular to the flow direction of the current can be determined by tomography, and the area of ​​the minimum cross-section of the connector 25 perpendicular to the flow direction of the current can be determined, that is, the minimum flow area of ​​the connector 25. In other words, the minimum flow area of ​​the connector 25 is also obtained by tomography.

[0187] The minimum flow area of ​​the first current collecting member 24 refers to the minimum cross-sectional area of ​​the first current collecting member 24 for current to pass through on the flow path of current flowing from the first electrode tab 232 through the first current collecting member 24 to the first electrode terminal 22 or from the first electrode terminal 22 through the first current collecting member 24 to the first electrode tab 232, that is, in the direction in which the first current collecting member 24 supplies current, the area of ​​the minimum cross-sectional area of ​​the first current collecting member 24 perpendicular to the direction of current flow.

[0188] Among them, the position of the minimum flow area of ​​the first current collecting member 24 can be determined by tomography, that is, the position of the minimum cross-section of the first current collecting member 24 perpendicular to the flow direction of the current can be determined by tomography, and the area of ​​the minimum cross-section of the first current collecting member 24 perpendicular to the flow direction of the current can be determined, that is, the minimum flow area of ​​the first current collecting member 24. In other words, the minimum flow area of ​​the first current collecting member 24 is also obtained by tomography.

[0189] The minimum flow area of ​​the connector 25 is smaller than that of the first current collecting member 24 . That is, on the current flow path, the minimum cross-sectional area of ​​the connector 25 for current to pass through is smaller than that of the first current collecting member 24 .

[0190] It should be noted that, in the current flow path, the minimum cross-sectional area of ​​the connector 25 for current to pass through is smaller than the minimum cross-sectional area of ​​the first current collecting member 24 for current to pass through. According to the resistance formula (R=ρL / S), the resistance of the connector 25 at the minimum flow area is greater than the resistance of the first current collecting member 24. When the second tab 233 of the electrode assembly 23 overlaps with the housing 21, causing a short circuit in the battery cell 20, according to the heat formula (Q=I 2 Rt) shows that, within the same time, the heat generated by the connector 25 at the minimum flow area is higher than that of the first current collecting member 24, and the heat accumulation speed is faster than that of the first current collecting member 24. As a result, when the second pole ear 233 and the shell 21 overlap each other and cause a short circuit in the battery cell 20, the connector 25 will be preferentially and more likely to fuse than the first current collecting member 24, so that when a short circuit occurs in the battery cell 20, the electrical connection between the connector 25 and the wall 211 of the shell 21 can be disconnected, thereby cutting off the short circuit path and alleviating the use risk further caused by the short circuit of the battery cell 20.

[0191] Illustratively, the material of the connecting member 25 is the same as that of the first current collecting member 24 . For example, the material of the connecting member 25 may be copper, iron, aluminum, steel, aluminum alloy, or the like.

[0192] In some embodiments, referring to Figures 4, 5 and 6, the battery cell 20 may further include a second insulating member 28. Along the thickness direction X of the wall portion, the second insulating member 28 is arranged on the side of the wall portion 211 facing the electrode assembly 23. The second insulating member 28 is configured to insulate and isolate the wall portion 211 and the main body 231 of the electrode assembly 23 to reduce the risk of short circuit between the main body 231 of the electrode assembly 23 and the wall portion 211.

[0193] The second insulating member 28 is provided with an avoidance hole 281 for the connecting member 25 to pass through. The avoidance hole 281 passes through both sides of the second insulating member 28 along the thickness direction X of the wall. The connecting member 25 is inserted into the avoidance hole 281 and connected to the wall 211.

[0194] For example, the second insulating member 28 can be made of various materials, such as rubber, silicone, or plastic.

[0195] In some embodiments, as shown in Figures 3 and 4, the battery cell 20 may further include a pressure relief mechanism 29, which is provided on the housing 21 and is used to release the internal pressure of the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value.

[0196] Optionally, the pressure relief mechanism 29 may be provided on the end cover 213 of the housing 21 or on the shell 212 of the housing 21. For example, in FIG3 and FIG4 , the pressure relief mechanism 29 is provided on the end cover 213.

[0197] Similarly, the pressure relief mechanism 29 and the housing 21 can be integrally formed or separately formed. For example, in FIG4 , the pressure relief mechanism 29 and the housing 21 are separate structures, and the pressure relief mechanism 29 can be connected to the housing 21 by welding or other methods. Accordingly, the pressure relief mechanism 29 can be a pressure relief component such as an explosion-proof valve, explosion-proof disk, air valve, pressure relief valve, or safety valve. Of course, in other embodiments, the pressure relief mechanism 29 and the housing 21 can also be integrally formed, in which case the pressure relief mechanism 29 is an area of ​​the housing 21 where a weak structure is formed, such as an area of ​​the housing 21 where a notched groove is provided.

[0198] In this embodiment, a connector 25 is further provided in the battery cell 20, and the first current collecting member 24 and the wall portion 211 of the shell 21 are connected by the connector 25, so that the positive or negative electrode of the electrode assembly 23 can be electrically connected to the shell 21, so that the information acquisition device can collect usage information of the battery cell 20 after being electrically connected to the shell 21, thereby facilitating the information acquisition device to connect the battery cell 20 and perform data acquisition, which is conducive to reducing the difficulty of data acquisition of the battery cell 20, wherein, by setting the minimum flow area of ​​the connector 25 to be smaller than the minimum flow area of ​​the first current collecting member 24, so that the minimum cross-sectional area of ​​the connector 25 on the path for current passage is smaller than the minimum cross-sectional area of ​​the first current collecting member 24 on the path for current passage, the connection The resistance of the component 25 at the minimum flow area is greater than the resistance of the first current collecting component 24. Therefore, within the same time, the heat generated by the connector 25 when the electrode assembly 23 inside the battery cell 20 and the shell 21 overlap and short-circuit occurs is higher and the heat accumulates faster, so that the connector 25 can be melted preferentially compared to the first current collecting component 24 when the electrode assembly 23 inside the battery cell 20 and the shell 21 overlap and short-circuit occurs, so that the battery cell 20 can disconnect the electrical connection between the first current collecting component 24 and the shell 21 after a short circuit occurs, and then cut off the short-circuit path, thereby alleviating damage to the information collection equipment and the like, and can effectively reduce the further use risk caused by the battery cell 20, which is conducive to improving the use reliability of the battery cell 20.

[0199] According to some embodiments of the present application, the minimum flow area of ​​the connector 25 is S1, which satisfies the following conditions: 2mm 2 ≤S1≤20mm 2 That is, on the path of the connecting member 25 for current flow, the minimum cross-sectional area of ​​the connecting member 25 perpendicular to the direction of current flow is 2 mm 2 Up to 20mm 2 .

[0200] For example, the minimum flow area S1 of the connector 25 may be 2 mm 2 , 2.1mm 2 , 2.2mm 2 , 2.5mm 2 , 3mm 2 , 3.5mm 2 , 4mm 2 , 5mm 2 , 6mm 2 , 7mm 2 , 8mm 2 , 9mm 2 , 10mm 2 , 11mm 2 , 12mm 2 , 15mm2 , 16mm 2 , 18mm 2 or 20mm 2 wait.

[0201] In this embodiment, by setting the minimum flow area of ​​the connecting member 25 to 2mm 2 Up to 20mm 2 On the one hand, the minimum flow area of ​​the connector 25 is set to be greater than or equal to 2mm 2 , in order to improve the structural strength of the connector 25, thereby reducing the risk of accidental breakage of the connector 25 during use, which is beneficial to improving the service life and stability of the battery cell 20. On the other hand, the minimum flow area of ​​the connector 25 is set to be less than or equal to 20mm 2 , in order to alleviate the phenomenon that the time required for the connector 25 to melt when a short circuit occurs in the battery cell 20 is too long, and make the connector 25 more likely to melt, so that the connector 25 can be quickly melted when a short circuit occurs in the battery cell 20 to cut off the short circuit path, thereby further alleviating the phenomenon of damage to the information collection equipment and further improving the reliability of the battery cell 20. Therefore, the minimum flow area of ​​the connector 25 is set to 2mm 2 Up to 20mm 2 , while ensuring that the connector 25 has sufficient strength during use, it can also ensure that the connector 25 quickly fuses when a short circuit occurs in the battery cell 20.

[0202] According to some embodiments of the present application, referring to Figures 4, 5, and 6, and further referring to Figure 7, Figure 7 is a cross-sectional view of a connector 25 of a battery cell 20 provided in some embodiments of the present application. The connector 25 is provided separately from the first current collecting member 24.

[0203] The connector 25 is separately provided from the first current collecting member 24 , that is, the connector 25 and the first current collecting member 24 are two independent components, and the connector 25 connects the first current collecting member 24 and the wall portion 211 , so that the first current collecting member 24 can be electrically connected to the wall portion 211 through the connector 25 .

[0204] Alternatively, in an embodiment where the connector 25 and the first current collecting member 24 are provided separately, the connector 25 may be an elastic member, a conductor, or a metal wire, etc., connected between the first current collecting member 24 and the wall portion 211. Similarly, the connection structures between the connector 25 and the first current collecting member 24 and between the connector 25 and the wall portion 211 may also be various, such as welding, abutment, or clamping.

[0205] For example, as shown in Figures 6 and 7, the connector 25 is a spring disposed within the housing 21, and the ends of the spring in the wall thickness direction X respectively abut against the first current collecting member 24 and the wall portion 211, thereby electrically connecting the first current collecting member 24 to the wall portion 211 via the connector 25. It should be noted that in the embodiment where the connector 25 is a spring, the minimum flow area S1 of the connector 25 is the area of ​​the minimum cross-section of the spring perpendicular to its spiral direction.

[0206] In this embodiment, by setting the connecting member 25 and the first current collecting member 24 as a separate structure, on the one hand, it is convenient to separately process and form the connecting member 25 and the first current collecting member 24, so that the production process of the connecting member 25 and the first current collecting member 24 can be carried out simultaneously, thereby optimizing the production rhythm of the battery cell 20, which is beneficial to improving the production efficiency of the battery cell 20. On the other hand, it is convenient to replace or maintain the connecting member 25 during the use of the battery cell 20, which is beneficial to reducing the later maintenance cost of the battery cell 20.

[0207] According to some embodiments of the present application, referring to Figures 4, 6 and 7, along the thickness direction X of the wall portion, the first current collecting member 24 is arranged between the main body 231 and the wall portion 211, and the connecting member 25 is an elastic member arranged between the first current collecting member 24 and the wall portion 211. The two ends of the connecting member 25 are respectively abutted against the first current collecting member 24 and the wall portion 211 to electrically connect the first current collecting member 24 and the wall portion 211.

[0208] The connector 25 is an elastic member disposed between the first current collecting member 24 and the wall portion 211. The connector 25 can have various structures, such as a spring, a V-shaped spring plate, or a C-shaped spring plate disposed between the first current collecting member 24 and the wall portion 211. For example, in Figures 6 and 7 , the connector 25 is a spring disposed between the first current collecting member 24 and the wall portion 211. The spiral centerline of the spring extends along the thickness direction X of the wall portion, and the ends of the spring in the thickness direction X of the wall portion respectively abut against the first current collecting member 24 and the wall portion 211.

[0209] In this embodiment, the connecting member 25 is set as an elastic member located between the first current collecting member 24 and the wall portion 211, and the two ends of the elastic member in the thickness direction X of the wall portion are respectively abutted against the wall portion 211 and the first current collecting member 24, so that the connecting member 25 is electrically connected to the first current collecting member 24 and the wall portion 211, which has a simple structure and is easy to assemble.

[0210] According to some embodiments of the present application, referring to FIG7 and further referring to FIG8 , FIG8 is a partial enlarged view of point B of the connector 25 shown in FIG7 . In the extension direction of the connector 25 , a portion of the connector 25 forms a weak section 251 , and the housing 21 is electrically connected to the first current collecting member 24 via the weak section 251 . The minimum flow area of ​​the weak section 251 is the minimum flow area S1 of the connector 25 .

[0211] The extending direction of the connecting member 25 is the direction in which the current flows through the connecting member 25. In FIG7 , the connecting member 25 is a spring, and the extending direction of the connecting member 25 is the spiral direction of the spring. In other embodiments, if the connecting member 25 is a V-shaped spring clip or a C-shaped spring clip, the extending direction of the connecting member 25 is the extending direction of the length of the spring clip.

[0212] A portion of the connector 25 forms a weak section 251. Specifically, a weak section is formed in the connector 25 in the direction of extension or along the path through which current flows. This section, referred to as the weak section 251, electrically connects the wall portion 211 and the first current collecting member 24 via the weak section 251 of the connector 25. Current flowing between the wall portion 211 and the first current collecting member 24 passes through the weak section 251 of the connector 25. The cross-sectional area of ​​the weak section 251 perpendicular to the direction of extension of the connector 25 is the minimum flow area S1 of the connector 25. In other words, the weak section 251 of the connector 25 represents the minimum flow area of ​​the connector 25, and the cross-sectional area of ​​the weak section 251 perpendicular to the direction of extension of the connector 25 represents the minimum flow area of ​​the connector 25.

[0213] For example, referring to Figures 7 and 8, the connecting member 25 is a spring. In the extension direction of the connecting member 25, the wire diameter of a local area of ​​the spring is smaller than the wire diameter of other areas, and the area with smaller wire diameter of the spring is the weak section 251 of the connecting member 25, that is, the wire diameter of the weak section 251 of the connecting member 25 is smaller than the wire diameter of other areas of the connecting member 25.

[0214] In this embodiment, the connector 25 forms a weak section 251 in the portion in its extension direction, so that the minimum flow area of ​​the weak section 251 of the connector 25 is the minimum flow area of ​​the connector 25, so that when a short circuit occurs in the battery cell 20, the weak section 251 of the connector 25 can be fused. On the one hand, by providing the weak section 251 on the connector 25, the minimum flow area of ​​the connector 25 can be made smaller than the minimum flow area of ​​the first pole ear 232, which has a simple structure and is easy to manufacture. On the other hand, the fusing position of the connector 25 can be controlled, and the fusing position can be controlled in the area where the weak section 251 is located, so as to facilitate the assembly of the connector 25 and avoid the weak section 251 during the assembly process, which is conducive to reducing the difficulty of assembling the connector 25.

[0215] According to some embodiments of the present application, as shown in FIG. 7 , along the extension direction of the connecting member 25 , the length of the weak section 251 is L1 , satisfying 0.3 mm ≤ L1 ≤ 5 mm.

[0216] The length L1 of the weak section 251 refers to the length L1 of the weak section 251 along the path of current flow in the connector 25. For example, in FIG7 , the connector 25 is a spring having a weakened region where the wire diameter is reduced. This region is the weak section 251 of the connector 25. Accordingly, the length L1 of the weak section 251 is the length of the weak section 251 along the helical direction of the spring. In other words, the length of the region where the wire diameter is reduced is L1. Of course, if the connector 25 is a V-shaped or C-shaped spring clip, the length L1 of the weak section 251 is the length of the weak section 251 along the length of the spring clip.

[0217] Illustratively, the length L1 of the weak section 251 may be 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm, etc.

[0218] In this embodiment, by setting the length of the weak section 251 in the extension direction of the connector 25 to 0.3 mm to 5 mm, on the one hand, the length of the weak section 251 is set to be greater than or equal to 0.3 mm, so that the connector 25 has sufficient space to fuse when a short circuit occurs in the battery cell 20, thereby effectively reducing the phenomenon of incorrect overlapping of the weak section 251 of the connector 25 after melting, thereby reducing the overlapping risk of the connector 25 after melting. On the other hand, the length of the weak section 251 is set to be less than or equal to 5 mm to alleviate the phenomenon of excessive space occupied by the weak section 251, thereby improving the internal space utilization rate of the battery cell 20. Therefore, the length of the weak section 251 in the extension direction of the connector 25 is set to 0.3 mm to 5 mm, which can take into account the reduction of the risk of incorrect overlapping of the weak section 251 of the connector 25 after melting, and can also effectively save the space occupied by the weak section 251 of the connector 25.

[0219] 7 and 8 , the connector 25 may further include a first insulating member 252, which covers the outside of the weak section 251. In other words, the first insulating member 252 covers the outside of the region of the connector 25 where the weak structure is formed.

[0220] Among them, the first insulating member 252 is covered on the outside of the weak section 251, so that the first insulating member 252 plays the role of protecting or insulating the weak section 251 from other components. The structure of the first insulating member 252 can be various. For example, the first insulating member 252 can be an insulating tape or insulating rubber layer covered on the outside of the weak section 251 of the connector 25.

[0221] For example, in FIG. 8 , the first insulating member 252 is an insulating rubber layer covering the outer side of the weak section 251 . The first insulating member 252 may be made of various materials, such as rubber, silicone, or plastic.

[0222] In this embodiment, the first insulating member 252 is wrapped around the outer side of the weak section 251 of the connector 25, so that on the one hand the first insulating member 252 can play a certain protective role on the weak section 251, thereby reducing the risk of the weak section 251 being accidentally broken due to wear or collision, which is beneficial to improving the service life of the connector 25. On the other hand, since the connector 25 is an elastic member with a certain elastic force, the weak section 251 of the connector 25 can still play a certain insulating isolation role through the first insulating member 252 after it melts when a short circuit occurs in the battery cell 20, thereby reducing the phenomenon that the weak section 251 overlaps with the wall 211 or the first current collecting component 24 under the elastic force of the connector 25 after it melts, thereby reducing the risk of the weak section 251 of the connector 25 overlapping with other components after it melts.

[0223] According to some embodiments of the present application, as shown in Figures 6 and 7 , the connector 25 may further include a first connecting section 253. The minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251. Along the thickness direction X of the wall, the first connecting section 253 is connected to an end of the weak section 251 that is close to the wall 211, and the first connecting section 253 abuts the wall 211.

[0224] The minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251, that is, in the extension direction of the connecting member 25, the cross-sectional area of ​​the first connecting section 253 is greater than the cross-sectional area of ​​the weak section 251. For example, in an embodiment where the connecting member 25 is a spring, the minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251 because the wire diameter of the first connecting section 253 is greater than the wire diameter of the weak section 251.

[0225] In this embodiment, the connector 25 is further provided with a first connecting section 253, so that the weak section 251 of the connector 25 is a structure in which the first connecting section 253 abuts against the wall portion 211, and the minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251. Therefore, while the connector 25 can be fused at the weak section 251, the stability and reliability of the mutual abutment between the connector 25 and the wall portion 211 can be improved through the structure in which the first connecting section 253 abuts against the wall portion 211, which is beneficial to improving the flow area between the connector 25 and the wall portion 211.

[0226] According to some embodiments of the present application, as shown in Figures 6 and 7 , the connector 25 may further include a second connecting segment 254, wherein the minimum flow area of ​​the second connecting segment 254 is greater than the minimum flow area of ​​the weak segment 251. Along the thickness direction X of the wall portion, the second connecting segment 254 is connected to an end of the weak segment 251 that is adjacent to the first current collecting member 24, and the second connecting segment 254 abuts against the first current collecting member 24.

[0227] The minimum flow area of ​​the second connecting segment 254 is greater than the minimum flow area of ​​the weak segment 251, that is, in the extension direction of the connecting member 25, the cross-sectional area of ​​the second connecting segment 254 is greater than the cross-sectional area of ​​the weak segment 251. For example, in an embodiment where the connecting member 25 is a spring, the minimum flow area of ​​the second connecting segment 254 is greater than the minimum flow area of ​​the weak segment 251 because the wire diameter of the second connecting segment 254 is greater than the wire diameter of the weak segment 251. Optionally, the wire diameter of the first connecting segment 253 of the connecting member 25 is equal to the wire diameter of the second connecting segment 254 of the connecting member 25, thereby facilitating processing. The weak segment 251 of the spring can be formed by simply reducing the wire diameter of the middle region of the spring, and the first connecting segment 253 and the second connecting segment 254 are respectively formed on either side of the weak segment 251 along the thickness direction X of the wall.

[0228] In this embodiment, the connector 25 is also provided with a second connecting section 254, so that the weak section 251 of the connector 25 is a structure that abuts against the first current collecting component 24 through the second connecting section 254, and the minimum flow area of ​​the second connecting section 254 is greater than the minimum flow area of ​​the weak section 251. Therefore, while the connector 25 can be fused in the weak section 251, the stability and reliability of the mutual abutment between the connector 25 and the first current collecting component 24 can be improved through the structure in which the second connecting section 254 abuts against the first current collecting component 24, which is conducive to improving the flow area between the connector 25 and the first current collecting component 24.

[0229] According to some embodiments of the present application, as shown in FIG. 6 and FIG. 7 , the connecting member 25 is a spring, and along the thickness direction X of the wall portion, two ends of the spring respectively abut against the first current collecting member 24 and the wall portion 211 .

[0230] The connector 25 can be a spring in various configurations. For example, the connector 25 can be a conical spring or a cylindrical spring. For example, in FIG7 , the connector 25 is a conical spring, and the outer diameter of the end of the connector 25 that abuts the wall 211 in the wall thickness direction X is greater than the outer diameter of the end of the connector 25 that abuts the first current collecting member 24 in the wall thickness direction X. Of course, in other embodiments, as shown in FIG9 , which is a partial cross-sectional view of the connector 25 of the battery cell 20 provided in some embodiments of the present application, the connector 25 can also be a cylindrical spring.

[0231] In this embodiment, by setting the connecting member 25 as a spring that abuts between the first current collecting component 24 and the wall portion 211, the connecting member 25 with this structure is easy to assemble, which is beneficial to reducing the difficulty of assembling the connecting member 25 between the wall portion 211 and the first current collecting component 24, and is beneficial to improving the structural stability of the connecting member 25 abutting between the wall portion 211 and the first current collecting component 24, thereby improving the assembly stability of the connecting member 25.

[0232] According to some embodiments of the present application, referring to Figures 6 and 7, and further referring to Figures 10 and 11, Figure 10 is a schematic diagram of the assembly of the wall portion 211 and the connector 25 of the battery cell 20 provided in some embodiments of the present application, and Figure 11 is a partial cross-sectional view of the wall portion 211 of the battery cell 20 provided in some embodiments of the present application. Along the thickness direction X of the wall portion, the side of the wall portion 211 facing the electrode assembly 23 is provided with a receiving portion 2111, and a portion of the connector 25 is inserted into the receiving portion 2111.

[0233] Among them, the accommodating portion 2111 is an accommodating space arranged on the surface of the wall portion 211 facing the electrode assembly 23 in the thickness direction X of the wall portion, so that the end of the connecting member 25 away from the first current collecting member 24 in the thickness direction X of the wall portion can be inserted into the accommodating portion 2111.

[0234] For example, in FIG11 , the receiving portion 2111 is a blind hole provided on the surface of the wall portion 211 facing the electrode assembly 23. The end of the connector 25 that is away from the first current collecting member 24 in the wall thickness direction X is inserted into the blind hole and abuts against the bottom surface of the blind hole. Of course, in other embodiments, the receiving portion 2111 may also be a groove or stepped hole provided on the wall portion 211.

[0235] In this embodiment, an accommodating portion 2111 for partially inserting the connector 25 is provided on the side of the wall portion 211 facing the electrode assembly 23, so that the end of the connector 25 abutting against the wall portion 211 in the thickness direction X of the wall portion can be inserted into the accommodating portion 2111 of the wall portion 211. Therefore, on the one hand, the accommodating portion 2111 can play a certain positioning role for the connector 25, which is beneficial to reducing the difficulty of assembling the connector 25 between the wall portion 211 and the first current collecting member 24, thereby improving the production efficiency of the battery cell 20, and is beneficial to improving the assembly accuracy of the connector 25 between the wall portion 211 and the first current collecting member 24. On the other hand, the accommodating portion 2111 can play a certain limiting role for the connector 25 in the radial direction of the connector 25, which is beneficial to improving the structural stability of the connector 25 assembled between the wall portion 211 and the first current collecting member 24, thereby reducing the shaking of the connector 25 during use.

[0236] According to some embodiments of the present application, as shown in Figures 10 and 11, the side of the accommodating portion 2111 includes a limiting surface 2111a, which is configured to limit the connection member 25 from detaching from the accommodating portion 2111 along the thickness direction X of the wall.

[0237] Among them, the side surface of the accommodating portion 2111 includes a limiting surface 2111a, that is, the side surface of the accommodating portion 2111 is formed with a limiting surface 2111a for limiting the connecting member 25 within the accommodating portion 2111. It should be noted that the entire side surface of the accommodating portion 2111 can be the limiting surface 2111a, that is, the entire side surface of the accommodating portion 2111 forms an inclined limiting surface 2111a structure to limit the connecting member 25 from detaching from the accommodating portion 2111. Of course, part of the side surface of the accommodating portion 2111 can also form an inclined limiting surface 2111a structure, that is, part of the side surface of the accommodating portion 2111 forms a limiting surface 2111a.

[0238] For example, in an embodiment where the accommodation portion 2111 is a blind hole, the hole wall of the blind hole forms a limiting surface 2111 a for limiting the connection member 25 from separating from the accommodation portion 2111 .

[0239] In this embodiment, a limiting surface 2111a is formed on the side of the accommodating portion 2111, and the limiting surface 2111a can limit the connection member 25 from detaching from the accommodating portion 2111 in the thickness direction X of the wall portion, so as to further enhance the structural stability of the connection member 25 assembled between the wall portion 211 and the first current collecting component 24, thereby effectively reducing the phenomenon of the connection member 25 falling off during use, thereby reducing the risk of connection failure between the wall portion 211 and the first current collecting component 24.

[0240] In some embodiments, referring to Figures 7, 10 and 11, the connecting member 25 is a conical spring, the limiting surface 2111a is a conical surface that fits the outer peripheral surface of the conical spring, and along the thickness direction X of the wall, the large end of the limiting surface 2111a is farther away from the first current collecting component 24 than the small end of the limiting surface 2111a.

[0241] Among them, the limiting surface 2111a is a conical surface that fits with the outer peripheral surface of the conical spring, that is, the side surface of the accommodating portion 2111 is a conical surface. In other words, in the embodiment where the accommodating portion 2111 is a blind hole, the hole wall surface of the blind hole is a conical surface structure, and correspondingly, the blind hole is conical.

[0242] The larger end of the limiting surface 2111a is further away from the first current collecting member 24 than the smaller end of the limiting surface 2111a. That is, in the wall thickness direction X, the aperture diameter of the side surface of the accommodating portion 2111, which penetrates the surface of the wall 211 facing the electrode assembly 23, is smaller than the aperture diameter of the side surface of the accommodating portion 2111, which is closer to the bottom. Correspondingly, the outer diameter of the conical spring connector 25, which is closer to the first current collecting member 24 in the wall thickness direction X, is smaller than the outer diameter of the conical spring connector 25, which is farther away from the first current collecting member 24 in the wall thickness direction X. It should be noted that the larger end of the limiting surface 2111a is the end of the conical limiting surface 2111a with the largest aperture, and correspondingly, the smaller end of the limiting surface 2111a is the end of the conical limiting surface 2111a with the smallest aperture.

[0243] In this embodiment, the connecting member 25 is configured as a conical spring so that the connecting member 25 is conical. Correspondingly, the limiting surface 2111a of the accommodating portion 2111 is configured as a conical surface that fits with the outer peripheral surface of the connecting member 25, and the small end of the limiting surface 2111a is located between the large end of the limiting surface 2111a and the first current collecting member 24 in the thickness direction X of the wall portion, so that after the connecting member 25 is inserted into the accommodating portion 2111, the limiting surface 2111a of the accommodating portion 2111 can limit the connecting member 25 to restrict the connecting member 25 in the accommodating portion 2111. The structure is simple and easy to manufacture.

[0244] In some embodiments, as shown in Figures 10 and 11, the diameter of the large end of the limiting surface 2111a in the thickness direction X of the wall is D1, and the diameter of the small end of the limiting surface 2111a in the thickness direction X of the wall is D2, satisfying 0.5mm≤D1-D2≤5mm.

[0245] In FIG11 , the diameter of the larger end of the limiting surface 2111a in the wall thickness direction X is D1, that is, the diameter of the end of the limiting surface 2111a away from the first current collecting member 24 in the wall thickness direction X is D1. The diameter of the smaller end of the limiting surface 2111a in the wall thickness direction X is D2, and the diameter of the end of the limiting surface 2111a closer to the first current collecting member 24 in the wall thickness direction X is D2.

[0246] 0.5mm≤D1-D2≤5mm, that is, the difference in diameter between the two ends of the conical limiting surface 2111a is 0.5mm to 5mm. For example, the difference between the diameter D1 of the large end of the limiting surface 2111a and the diameter D2 of the small end of the limiting surface 2111a can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.2mm, 4.5mm, 4.8mm, or 5mm, etc.

[0247] In this embodiment, by setting the difference between the diameter of the large end of the limiting surface 2111a and the diameter of the small end of the limiting surface 2111a to be greater than or equal to 0.5 mm, the limiting effect of the limiting surface 2111a on the connecting member 25 is improved, thereby further reducing the phenomenon of the connecting member 25 being separated from the accommodating portion 2111 along the thickness direction X of the wall portion, thereby further reducing the risk of connection failure between the wall portion 211 and the first current collecting member 24. The difference in diameter between the ends is set to be less than or equal to 5 mm to alleviate the difficulty of assembling the connector 25 into the accommodating portion 2111, which is beneficial to reducing the difficulty of assembling the connector 25 and the wall portion 211. Therefore, the difference between the diameter of the large end of the limiting surface 2111a and the diameter of the small end of the limiting surface 2111a is set to 0.5 mm to 5 mm, which can not only achieve a better limiting effect of the limiting surface 2111a on the connector 25, but also reduce the difficulty of inserting the connector 25 into the accommodating portion 2111.

[0248] According to some embodiments of the present application, as shown in FIG. 6 and FIG. 7 , along the thickness direction X of the wall portion, the compression ratio of the connecting member 25 is 10%-50%.

[0249] The compression ratio of the connector 25 is 10%-50%. That is, in the thickness direction X of the wall portion, the difference between the length of the connector 25 in its natural state (the length of the connector 25 when not under force) and the length of the connector 25 after being assembled between the wall portion 211 and the first current collecting member 24 (the length of the connector 25 compressed between the wall portion 211 and the first current collecting member 24 when under force) divided by the length of the connector 25 in its natural state (the length of the connector 25 when not under force) is 10%-50%. In other words, after the connector 25 is assembled between the wall portion 211 and the first current collecting member 24, the length compressed in the thickness direction X of the wall portion is 10% to 50% of the original length of the connector 25 in the thickness direction X of the wall portion.

[0250] In this embodiment, the compression ratio of the spring serving as the connector 25 before assembly and after assembly between the wall portion 211 and the first current collecting component 24 is 10% to 50%. On the one hand, the compression ratio of the connector 25 is set to be greater than or equal to 10% to enhance the effect of the connector 25 abutting between the wall portion 211 and the first current collecting component 24, and is beneficial to enhancing the structural stability of the connector 25 assembled between the wall portion 211 and the first current collecting component 24. On the other hand, the compression ratio of the connector 25 is set to be less than or equal to 50% to alleviate the phenomenon of plastic deformation caused by excessive compression of the connector 25, thereby benefiting to improving the service life of the connector 25. Therefore, the compression ratio of the connector 25 is set to 10% to 50%, which can take into account the better abutment effect of the connector 25 with the wall portion 211 and the first current collecting component 24, while also alleviating the phenomenon of the connector 25 being unable to recover elastic deformation due to excessive compression.

[0251] According to some embodiments of the present application, referring to Figures 12, 13, 14, and 15, Figure 12 is an exploded view of the structure of a battery cell 20 provided in still other embodiments of the present application, Figure 13 is a cross-sectional view of a battery cell 20 provided in still other embodiments of the present application, Figure 14 is a partial enlarged view of a portion C of the battery cell 20 shown in Figure 12, and Figure 15 is a schematic diagram of the connection between a connector 25 and a first current collecting member 24 of a battery cell 20 provided in still other embodiments of the present application. The connector 25 and the first current collecting member 24 are integrally formed.

[0252] Among them, the connecting member 25 and the first current collecting member 24 are integrally formed, that is, the connecting member 25 and the first current collecting member 24 are components formed by an integral molding process. For example, the connecting member 25 and the first current collecting member 24 can be integrally formed on one component by casting, stamping or milling to form the connecting member 25 and the first current collecting member 24 that are connected to each other.

[0253] In this embodiment, by setting the connector 25 and the first current collecting member 24 as an integrally formed structure, it is beneficial to improve the connection stability and reliability between the connector 25 and the first current collecting member 24, so as to reduce the risk of connection failure between the connector 25 and the first current collecting member 24, and the connector 25 and the first current collecting member 24 can be assembled in the outer shell 21 at the same time, which is beneficial to optimize the production rhythm of the battery cell 20 and improve the production efficiency of the battery cell 20.

[0254] In some embodiments, referring to Figures 13, 14, and 15, and further referring to Figure 16, Figure 16 is a cross-sectional view of a battery cell 20, provided in still other embodiments of the present application, showing a connector 25 connected to a first current collecting member 24. Along the thickness direction X of the wall portion, the first current collecting member 24 is disposed between the main body 231 and the wall portion 211. The first current collecting member 24 and the connector 25 are arranged along a first direction Y, which is perpendicular to the thickness direction X of the wall portion. Along the first direction Y, portions of the connector 25 form a weak section 251 connected to the first current collecting member 24. The minimum flow area of ​​the weak section 251 is equal to the minimum flow area S1 of the connector 25.

[0255] Part of the connector 25 forms a weak section 251. That is, in the first direction Y, the connector 25 has a weak section, which serves as the weak section 251. This allows the wall portion 211 and the first current collecting member 24 to be electrically connected via the weak section 251 of the connector 25. This means that current flowing between the wall portion 211 and the first current collecting member 24 passes through the weak section 251 of the connector 25. This means that the cross-sectional area of ​​the weak section 251 perpendicular to the first direction Y is the minimum flow area S1 of the connector 25. In other words, the weak section 251 of the connector 25 serves as the minimum flow area of ​​the connector 25, and the cross-sectional area of ​​the weak section 251 perpendicular to the first direction Y is the minimum flow area of ​​the connector 25.

[0256] The weak section 251 is connected to the first current collecting component 24, that is, the connecting member 25 is a structure connected to the first current collecting component 24 through the weak section 251. In other words, the part where the connecting member 25 and the first current collecting component 24 are connected is the weak section 251, and the minimum flow area of ​​the weak section 251 is smaller than the minimum flow area of ​​the connecting member 25.

[0257] In this embodiment, the first current collecting member 24 and the connector 25 are arranged along the first direction Y, and the portion of the connector 25 in the first direction Y forms a weak section 251 connected to the first current collecting member 24. This ensures that the minimum flow area of ​​the weak section 251 of the connector 25 is equal to the minimum flow area of ​​the connector 25. Therefore, when a short circuit occurs in the battery cell 20, the weak section 251 of the connector 25 can be fused. On the one hand, the connection between the weak section 251 of the connector 25 and the first current collecting member 24 allows the minimum flow area of ​​the connector 25 to be smaller than the minimum flow area of ​​the first tab 232. This facilitates the manufacture of the first current collecting member 24 and the connector 25, resulting in a simple structure and ease of manufacture. On the other hand, the fusion position of the connector 25 can be controlled and can be controlled to the portion where the weak section 251 is located, thereby facilitating assembly of the connector 25 and avoiding the weak section 251 during assembly, thereby reducing the difficulty of assembling the connector 25.

[0258] According to some embodiments of the present application, referring to FIG. 15 and FIG. 16 , along the first direction Y, the length of the weak section 251 is L2, satisfying 0.3 mm ≤ L2 ≤ 5 mm.

[0259] The length L2 of the weak section 251 is the dimension of the weak section 251 in the first direction Y, and is also the length L2 of the weak section 251 on the path for current flow in the connecting member 25 .

[0260] Exemplarily, the length L2 of the weak section 251 may be 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm, etc.

[0261] In this embodiment, by setting the length of the weak section 251 in the first direction Y to be 0.3 mm to 5 mm, that is, the length of the weak section 251 in the extending direction of the connector 25 is 0.3 mm to 5 mm, on the one hand, setting the length of the weak section 251 to be greater than or equal to 0.3 mm ensures that the connector 25 has sufficient space to fuse when a short circuit occurs in the battery cell 20, thereby effectively reducing the phenomenon of incorrect overlapping of the weak section 251 of the connector 25 after melting, thereby reducing the risk of overlapping of the connector 25 after melting. On the other hand, setting the length of the weak section 251 to be less than or equal to 5 mm alleviates the phenomenon of excessive space occupied by the weak section 251 in the first direction Y, thereby improving the internal space utilization of the battery cell 20. Therefore, setting the length of the weak section 251 in the first direction Y to be 0.3 mm to 5 mm can not only reduce the risk of incorrect overlapping of the weak section 251 of the connector 25 after melting, but also effectively save the space occupied by the weak section 251 of the connector 25 in the first direction Y.

[0262] According to some embodiments of the present application, referring to Figures 14, 15 and 16, the connector 25 may further include a first connecting section 253, the minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251, the first connecting section 253 is connected to the wall portion 211, the weak section 251 connects the first connecting section 253 and the first current collecting member 24, and the first current collecting member 24, the weak section 251 and the first connecting section 253 are arranged along the first direction Y.

[0263] The minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251 , that is, in the first direction Y, the cross-sectional area of ​​the first connecting section 253 is greater than the cross-sectional area of ​​the weak section 251 .

[0264] The first connecting section 253 is connected to the wall portion 211, and the weak section 251 connects the first connecting section 253 and the first current collecting member 24. That is, the first current collecting member 24 is a structure connected to the wall portion 211 through the weak section 251 of the connecting member 25 and the first connecting section 253 of the connecting member 25 in sequence, that is, the first current collecting member 24, the weak section 251, the first connecting section 253 and the wall portion 211 are connected in sequence. Optionally, the connection structure between the first connecting section 253 and the wall portion 211 can be various, such as welding connection, abutment or clamping, etc.

[0265] The first current collecting member 24 , the weak section 251 and the first connecting section 253 are arranged along the first direction Y. That is, in the first direction Y, the weak section 251 is located between the first current collecting member 24 and the first connecting section 253 , and the two ends of the weak section 251 in the first direction Y are respectively connected to the first current collecting member 24 and the first connecting section 253 .

[0266] In this embodiment, the connector 25 is also provided with a first connecting section 253, so that the weak section 251 of the connector 25 is a structure interconnected with the wall portion 211 through the first connecting section 253, so that the first current collecting component 24, the weak section 251, the first connecting section 253 and the wall portion 211 are structures connected in sequence, and the minimum flow area of ​​the first connecting section 253 is greater than the minimum flow area of ​​the weak section 251, so that the connector 25 can be fused in the weak section 251 while also being able to improve the connection area and connection reliability between the connector 25 and the wall portion 211 through the structure interconnected with the first connecting section 253 and the wall portion 211, which is beneficial to improving the flow area between the connector 25 and the wall portion 211.

[0267] According to some embodiments of the present application, as shown in Figures 14, 15, and 16, the first connecting section 253 includes a first connecting portion 2531, a bent portion 2532, and a second connecting portion 2533, which are connected in sequence. The first connecting portion 2531 is connected to the weak section 251, and the second connecting portion 2533 is connected to the wall portion 211. Along the thickness direction X of the wall portion, the second connecting portion 2533 is closer to the wall portion 211 than the first connecting portion 2531, and the second connecting portion 2533 abuts the wall portion 211.

[0268] Among them, the first connecting part 2531 is connected to the weak section 251, and the second connecting part 2533 is connected to the wall part 211, that is, the weak section 251, the first connecting part 2531, the bending part 2532 and the second connecting part 2533 are connected in sequence, and the second connecting part 2533 is connected to the wall part 211.

[0269] Along the thickness direction X of the wall, the second connection part 2533 is closer to the wall 211 than the first connection part 2531, that is, there is a height difference between the first connection part 2531 and the second connection part 2533 in the thickness direction X of the wall, and the second connection part 2533 is closer to the wall 211 than the first connection part 2531, so that the first connection section 253 formed by the interconnection of the first connection part 2531, the bending part 2532 and the second connection part 2533 has a "Z" shape structure.

[0270] In this embodiment, the first connecting section 253 is provided with a first connecting portion 2531, a bent portion 2532 and a second connecting portion 2533 connected in sequence. The first connecting portion 2531 is connected to the first current collecting member 24 through the weak section 251, and the second connecting portion 2533 is connected to the wall portion 211, so as to realize the electrical connection between the wall portion 211 and the first current collecting member 24 through the connector 25, wherein the second connecting portion 2533 is arranged closer to the wall portion 211 than the first connecting portion 2531 in the thickness direction X of the wall portion, so that the first connecting section 253 is a "Z"-shaped structure, The first connecting section 253 of this structure can compensate for the gap between the first current collecting component 24 and the wall portion 211 in the thickness direction X of the wall portion. On the one hand, it can improve the connection stability and connection reliability between the first connecting section 253 of the connector 25 and the wall portion 211, which is beneficial to improving the assembly quality between the connector 25 and the wall portion 211. On the other hand, there is no need to set other components to compensate for the gap between the first current collecting component 24 and the wall portion 211 in the thickness direction X of the wall portion, which is beneficial to reducing the assembly difficulty between the connector 25 and the wall portion 211, thereby improving the production efficiency of the battery cell 20.

[0271] 14 and 16 , along the thickness direction X of the wall, the first connection portion 2531 has a first surface 2531 a facing the wall 211 , and the first current collecting member 24 has a second surface 242 facing the wall 211 , which is flush with the first surface 2531 a .

[0272] Among them, the second surface 242 is flush with the first surface 2531a, that is, the first surface 2531a of the first connecting portion 2531 facing the wall portion 211 and the second surface 242 of the first current collecting component 24 facing the wall portion 211 are coplanar structures. It should be noted that, in the embodiment in which the first protrusion 241 is provided on the first current collecting component 24, the first protrusion 241 is protruded on the second surface 242 of the first current collecting component 24.

[0273] In this embodiment, by setting the first surface 2531a of the first connecting portion 2531 facing the wall portion 211 and the second surface 242 of the first current collecting member 24 facing the wall portion 211 to be flush with each other, on the one hand, the shape regularity and flatness between the first connecting portion 2531 and the first current collecting member 24 can be improved, which is conducive to reducing the difficulty of assembling the first current collecting member 24 and the connecting piece 25 into the shell 21, and the first current collecting member 24 and the first connecting portion 2531 can share part of the space in the thickness direction X of the wall portion, which is conducive to improving the internal space utilization of the battery cell 20. On the other hand, it is convenient to integrally form the first current collecting member 24 and the first connecting portion 2531 with the same plate material, and it is convenient to form a weak section 251 between the first current collecting member 24 and the first connecting portion 2531, which is conducive to reducing the difficulty of manufacturing the integrally formed first current collecting member 24 and the first connecting portion 2531.

[0274] In some embodiments, please continue to refer to Figures 14 and 16. Along the thickness direction X of the wall, the first connecting portion 2531 has a third surface 2531b away from the wall 211, and the first collecting member 24 has a fourth surface 243 away from the wall 211, and the fourth surface 243 is flush with the third surface 2531b.

[0275] The fourth surface 243 is flush with the third surface 2531 b , that is, the third surface 2531 b of the first connection portion 2531 facing away from the wall portion 211 and the fourth surface 243 of the first current collecting member 24 facing away from the wall portion 211 are coplanar.

[0276] In this embodiment, by setting the third surface 2531b of the first connecting portion 2531 facing away from the wall portion 211 and the fourth surface 243 of the first current collecting member 24 facing away from the wall portion 211 to be flush with each other, on the one hand, the shape regularity and flatness between the first connecting portion 2531 and the first current collecting member 24 can be improved, which is conducive to reducing the difficulty of assembling the first current collecting member 24 and the connecting piece 25 into the shell 21, and the first current collecting member 24 and the first connecting portion 2531 can share part of the space in the thickness direction X of the wall portion, which is conducive to improving the internal space utilization of the battery cell 20. On the other hand, it is convenient to integrally form the first current collecting member 24 and the first connecting portion 2531 with the same plate material, and it is convenient to form a weak section 251 between the first current collecting member 24 and the first connecting portion 2531, which is conducive to reducing the difficulty of manufacturing the integrally formed first current collecting member 24 and the first connecting portion 2531.

[0277] According to some embodiments of the present application, referring to FIG. 14 , FIG. 15 and FIG. 16 , the second connection portion 2533 is connected to the wall portion 211 by welding.

[0278] The connector 25 is a structure in which the second connecting portion 2533 of the first connecting section 253 is welded to the wall portion 211, and a weld mark 30 is formed between the second connecting portion 2533 and the wall portion 211 to achieve electrical connection between the connector 25 and the wall portion 211. Of course, in other embodiments, the second connecting portion 2533 may also be a structure that abuts or engages with the wall portion 211.

[0279] For example, laser welding or ultrasonic welding may be used between the second connection portion 2533 and the wall portion 211 .

[0280] In this embodiment, a welding connection structure is used to connect the second connection portion 2533 of the first connection and the wall portion 211, which is beneficial to improving the connection reliability and connection stability between the connector 25 and the wall portion 211, thereby reducing the phenomenon of connection failure between the connector 25 and the wall portion 211 due to accidental detachment of the connector 25 and the wall portion 211 during the use of the battery cell 20.

[0281] In some embodiments, the welding area between the second connection portion 2533 and the wall portion 211 is S2, which satisfies the following conditions: 30 mm 2 ≤S2≤100mm 2 .

[0282] The welding area S2 between the second connection portion 2533 and the wall portion 211 refers to the cross-sectional area S2 of the weld mark 30 formed by the welding connection between the second connection portion 2533 and the wall portion 211 at the interface between the second connection portion 2533 and the wall portion 211 .

[0283] In this embodiment, the welding area between the second connecting portion 2533 of the first connecting segment 253 and the wall portion 211 is set to 30 mm. 2 Up to 100mm 2 On the one hand, the welding area between the second connecting portion 2533 and the wall portion 211 is set to be greater than or equal to 30mm 2 , in order to improve the welding effect between the second connecting portion 2533 and the wall portion 211, thereby improving the connection reliability and connection stability between the connecting member 25 and the wall portion 211. On the other hand, the welding area of ​​the second connecting portion 2533 and the wall portion 211 is set to be less than or equal to 100mm 2 , in order to reduce the difficulty of welding between the second connecting portion 2533 and the wall portion 211, and to reduce the welding power required for welding the second connecting portion 2533 and the wall portion 211 to each other, thereby effectively reducing the difficulty of assembling between the connecting member 25 and the wall portion 211, which is beneficial to improving the production efficiency of the battery cell 20 and reducing the production cost of the battery cell 20. Therefore, the welding area of ​​the second connecting portion 2533 and the wall portion 211 is set to 30mm 2 Up to 100mm2 , while taking into account the welding quality between the connecting member 25 and the wall portion 211 , it can also effectively reduce the difficulty of welding and assembling between the connecting member 25 and the wall portion 211 .

[0284] According to some embodiments of the present application, as shown in FIG. 15 and FIG. 16 , along the first direction Y, a groove 255 is formed between the first current collecting member 24 and the first connecting section 253 , and a bottom wall of the groove 255 is a weak section 251 .

[0285] Among them, a groove 255 is formed between the first current collecting component 24 and the first connecting section 253, and the bottom wall of the groove 255 is a weak section 251, that is, in the integrally formed connector 25 and the first current collecting component 24, a groove 255 is formed between the first connecting section 253 of the connector 25 and the first current collecting component 24, so that the part of the connector 25 corresponding to the bottom surface of the groove 255 is the weak section 251 connecting the first connecting section 253 and the first current collecting component 24.

[0286] Optionally, the groove 255 may be located on one side of the weak section 251 in the thickness direction X of the wall portion, or may be located on one side of the weak section 251 in the second direction Z.

[0287] In this embodiment, a groove 255 is formed between the first current collecting member 24 and the first connecting section 253 of the connecting member 25, so that the area corresponding to the bottom wall of the groove 255 becomes the weak section 251 of the connecting member 25, so that the first current collecting member 24 and the connecting member 25 can be formed as an integral part by processing the structure of the groove 255 on a plate, and a weak section 251 connected to the first current collecting member 24 is formed on the connecting member 25, which has a simple structure and is easy to process and form.

[0288] In some embodiments, as shown in FIG. 15 and FIG. 16 , a groove 255 is formed on at least one side of the weak section 251 along the second direction Z, and the first direction Y, the second direction Z and the thickness direction X of the wall are perpendicular to each other.

[0289] In which, along the second direction Z, a groove 255 is formed on at least one side of the weak section 251 , that is, in the second direction Z, the groove 255 may be formed on only one side of the weak section 251 , or on both sides of the weak section 251 .

[0290] For example, in Figure 15, grooves 255 are formed on both sides of the weak section 251 in the second direction Z, and the grooves 255 pass through both sides of the connector 25 in the thickness direction X of the wall portion, so that the portion of the connector 25 located between the bottom surfaces of the two grooves 255 is the weak section 251 of the connector 25.

[0291] In this embodiment, a groove 255 is formed on at least one side of the weak section 251 along the second direction Z, so that the groove 255 is located on one side of the weak section 251 in the second direction Z, so that the weak section 251 is formed on the bottom wall of the groove 255. The structure is simple and easy to process.

[0292] Of course, the structure of the connector 25 is not limited to this. In some embodiments, Figures 17 and 18 illustrate a schematic diagram of the connection between the connector 25 of the battery cell 20 and the first current collecting member 24 in other embodiments of the present application. Figure 18 illustrates a cross-sectional view of the connection between the connector 25 of the battery cell 20 and the first current collecting member 24 in other embodiments of the present application. A groove 255 is formed on at least one side of the weak section 251 along the thickness direction X of the wall.

[0293] Among them, a groove 255 is formed on at least one side of the weak section 251 along the thickness direction X of the wall portion, that is, in the thickness direction X of the wall portion, the groove 255 can be formed on only one side of the weak section 251, or the groove 255 can be formed on both sides of the weak section 251.

[0294] For example, in Figures 17 and 18 , a groove 255 is formed on only one side of the weak section 251 in the wall thickness direction X. The groove 255 penetrates both ends of the connector 25 in the second direction Z. The groove 255 is located on the side of the weak section 251 facing the wall 211 in the wall thickness direction X, so that the portion of the connector 25 corresponding to the bottom surface of the groove 255 serves as the weak section 251 of the connector 25. Of course, in other embodiments, the groove 255 may also be provided on the side of the weak section 251 facing away from the wall 211 in the wall thickness direction X.

[0295] In this embodiment, a groove 255 is formed on at least one side of the weak section 251 in the thickness direction X of the wall portion, so that the groove 255 is located on one side of the weak section 251 in the thickness direction X of the wall portion, so that the weak section 251 is formed on the bottom wall of the groove 255. The structure is simple and easy to process.

[0296] According to some embodiments of the present application, as shown in Figures 4, 5, and 6, the first electrode tab 232 is the positive electrode tab of the electrode assembly 23. In other words, the first electrode tab 232 is a component formed by stacking and connecting the areas of the positive electrode sheets that are not coated with the positive electrode active material layer, so that after the connector 25 electrically connects the first current collecting member 24 and the wall portion 211, the wall portion 211 is positively charged.

[0297] In this embodiment, by setting the first pole ear 232 as the positive pole ear of the electrode assembly 23, the first pole ear 232 is used to output or input the positive electrode of the electrode assembly 23. Correspondingly, the connector 25 is used to output the positive electrode of the electrode assembly 23, so that the wall 211 is a positively charged structure when the information acquisition device performs data acquisition. The battery cell 20 adopting this structure can effectively alleviate the phenomenon of electrical corrosion of the outer shell 21 of the battery cell 20, thereby helping to improve the service life of the battery cell 20 and helping to reduce the risk of leakage of the battery cell 20 during use.

[0298] According to some embodiments of the present application, referring to Figures 3, 4 and 5, the first electrode terminal 22 is insulated and installed on the wall portion 211, along the thickness direction X of the wall portion, the first current collecting member 24 is arranged between the main body 231 and the wall portion 211, and the first electrode tab 232 is arranged at one end of the main body 231 facing the wall portion 211.

[0299] In this embodiment, the first electrode terminal 22 is insulated and mounted on the wall portion 211, and the first electrode tab 232 is provided at one end of the main body 231 facing the wall portion 211 in the thickness direction X of the wall portion, so that the first electrode terminal 22, the first current collecting member 24 and the first electrode tab 232 are all located on the side of the main body 231 facing the wall portion 211 in the thickness direction X of the wall portion. On the one hand, the difficulty of assembling the first electrode tab 232 and the first current collecting member 24, and the difficulty of assembling the first current collecting member 24 and the first electrode terminal 22 can be reduced, which is conducive to improving the production efficiency of the battery cell 20. On the other hand, there is no need to excessively extend the first electrode tab 232 or the first current collecting member 24, thereby reducing the risk of overlap between the first electrode tab 232 or the first current collecting member 24 and other components.

[0300] According to some embodiments of the present application, as shown in Figures 3, 4, and 5, the battery cell 20 may further include a second electrode terminal 26 and a second current collecting member 27. The second electrode terminal 26 is insulated and mounted on the housing 21, and the second current collecting member 27 is disposed within the housing 21. The electrode assembly 23 also includes a second electrode tab 233, which is disposed on the main body 231. The second electrode tab 233 has an opposite polarity to the first electrode tab 232 and is electrically connected to the second electrode terminal 26 via the second current collecting member 27.

[0301] Illustratively, the second electrode terminal 26 is insulated and mounted on the wall portion 211 , and correspondingly, the second electrode tab 233 is connected to one end of the main body 231 facing the wall portion 211 in the thickness direction X of the wall portion, and the second current collecting member 27 is arranged between the main body 231 and the wall portion 211 , so that the second electrode tab 233 is connected to the second electrode terminal 26 through the second current collecting member 27 .

[0302] In this embodiment, the battery cell 20 is also provided with a second electrode terminal 26 and a second current collecting member 27. Correspondingly, the electrode assembly 23 also includes a second pole ear 233. The polarity of the second pole ear 233 is opposite to that of the first pole ear 232, and the second pole ear 233 is connected to the second electrode terminal 26 through the second current collecting member 27, so that the first electrode terminal 22 and the second electrode terminal 26 cooperate to input or output the positive and negative poles of the battery cell 20. In this regard, by insulating the second electrode terminal 26 and installing it on the outer shell 21, it is helpful to reduce the risk of short circuit between the second electrode terminal 26 and the connector 25.

[0303] According to some embodiments of the present application, as shown in Figures 3 and 4, the outer shell 21 may include a shell 212 and an end cover 213, the interior of the shell 212 forms a accommodating cavity with an opening 2121, the accommodating cavity is used to accommodate the electrode assembly 23, the end cover 213 closes the opening 2121, and the end cover 213 is a wall portion 211.

[0304] The end cap 213 is the wall portion 211, that is, the connector 25 is electrically connected to the end cap 213 of the housing 21. In the embodiment where the first electrode terminal 22 and the second electrode terminal 26 are insulated and mounted on the wall portion 211, both the first electrode terminal 22 and the second electrode terminal 26 are insulated and mounted on the end cap 213 of the housing 21.

[0305] In this embodiment, by setting the wall portion 211 of the outer shell 21 as the end cover 213 of the outer shell 21 for closing the opening 2121 of the shell 212, the battery cell 20 adopting this structure facilitates the connection of the connector 25 to the wall portion 211 of the outer shell 21, which is beneficial to reducing the difficulty of assembling the battery cell 20 and improving the production efficiency of the battery cell 20.

[0306] It should be noted that the structure of the battery cell 20 is not limited to this. In some embodiments, the battery cell 20 may also have other structures. For example, the outer shell 21 includes a shell 212 and an end cap 213. The shell 212 includes an integrally formed side wall and a wall portion 211. The side wall is arranged around the wall portion 211. Along the thickness direction X of the wall portion, one end of the side wall is connected to the wall portion 211, and the other end encloses an opening 2121. The side wall and the wall portion 211 jointly define a receiving cavity for accommodating the electrode assembly 23. The end cap 213 closes the opening 2121. In other words, the connector 25 and the shell 212 are connected to the bottom wall arranged opposite the end cap 213 in the thickness direction X of the wall portion.

[0307] In this embodiment, by setting the wall portion 211 of the outer shell 21 as a wall arranged opposite to the end cover 213 in the thickness direction X of the wall portion of the shell 212, the battery cell 20 adopting this structure can make the wall portion 211 used for connecting to the connector 25 away from the end cover 213, so that there is no direct connection relationship between the wall portion 211 and the end cover 213, thereby alleviating the influence of the stress generated by the mutual assembly between the end cover 213 and the shell 212 on the connector 25, which is beneficial to improving the service life of the connector 25, and can alleviate the phenomenon that the force generated by other components pulling or twisting the wall portion 211 acts on the end cover 213, thereby reducing the risk of connection failure between the end cover 213 and the shell 212, and further helping to further reduce the risk of leakage of the battery cell 20 during use.

[0308] According to some embodiments of the present application, the present application further provides a battery 100 , which includes the battery cell 20 of any of the above solutions.

[0309] As shown in FIG. 2 , the battery 100 may further include a box body 10 , in which the battery cells 20 are accommodated.

[0310] In some embodiments, the box body 10 may include a first box body 11 and a second box body 12 . The first box body 11 and the second box body 12 cover each other, and the first box body 11 and the second box body 12 jointly define an assembly space for accommodating the battery cells 20 .

[0311] 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, and 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 jointly define an 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.

[0312] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder or a rectangular parallelepiped, etc. For example, in FIG2 , the box body 10 is a rectangular parallelepiped structure.

[0313] Optionally, the number of battery cells 20 disposed within the housing 10 may be one or more. For example, in FIG2 , the housing 10 of the battery 100 includes multiple battery cells 20, which may be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a configuration in which multiple battery cells 20 are connected in both series and parallel. Multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure formed by the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery 100 may comprise multiple battery cells 20 that are first connected in series, in parallel, or in a hybrid configuration to form a battery module, which is then further connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 10.

[0314] The battery 100 may further include other structures. For example, the battery 100 may further include a busbar component that connects the plurality of battery cells 20 to achieve electrical connection between the plurality of battery cells 20 .

[0315] It should be noted that in some embodiments, the battery 100 may not be provided with a housing 10. The battery 100 includes multiple battery cells 20, and the battery 100 composed of multiple battery cells 20 can be directly assembled on an electrical device to provide electrical energy to the electrical device through the multiple battery cells 20. In other words, the housing 10 can serve as part of the electrical device. Taking the vehicle 1000 as an example, the housing 10 can serve as part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 can form at least a portion of the floor of the vehicle 1000, or a portion of the housing 10 can form at least a portion of the crossbeam and longitudinal beam of the vehicle 1000.

[0316] In some embodiments, as shown in FIG2 , the battery 100 may further include a battery management system (not shown). The battery management system is electrically connected to the wall portion 211 and is configured to generate an early warning when the connector 25 is fused.

[0317] The battery management system is used to manage and monitor the usage status of the battery 100. The specific structure of the battery management system can be found in related technologies and will not be described in detail here.

[0318] The battery management system is configured to issue an early warning when the connector 25 melts. That is, when the connector 25 melts due to a short circuit in the battery cell 20, causing the first pole ear 232 of the electrode assembly 23 to be electrically disconnected from the wall 211 of the outer shell 21, the battery management system can receive a circuit breaker signal and issue an early warning message, such as an alarm or a warning.

[0319] In an embodiment, the battery 100 is also provided with a battery management system, which is electrically connected to the wall portion 211, and the battery management system can issue an early warning after a short circuit occurs in the battery cell 20 and causes the connector 25 to melt, so as to provide an early warning to the operator or user, thereby reducing the further damage or impact caused by the short circuit of the battery cell 20 to the operator or user, which is conducive to improving the reliability of the battery 100.

[0320] According to some embodiments of the present application, the present application further provides an electrical device, which includes the battery cell 20 of any of the above solutions, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0321] The electrical device may be any of the aforementioned devices or systems using the battery cell 20 .

[0322] According to some embodiments of the present application, as shown in Figures 3 to 8 and 10 to 11, a battery cell 20 is provided. The battery cell 20 includes a housing 21, a first electrode terminal 22, a second electrode terminal 26, an electrode assembly 23, a first current collecting member 24, a second current collecting member 27, and a connector 25. The housing 21 has a wall portion 211 and includes a shell 212 and an end cap 213. The interior of the shell 212 forms a receiving cavity having an opening 2121. The end cap 213 closes the opening 2121 and serves as the wall portion 211. The first electrode terminal 22 and the second electrode terminal 26 are both insulated and mounted on the wall portion 211. The electrode assembly 23 is housed within the accommodating cavity. The electrode assembly 23 includes a main body 231, a first electrode tab 232, and a second electrode tab 233. The first electrode tab 232 and the second electrode tab 233 are both connected to one end of the main body 231 that faces the wall 211 in the wall thickness direction X. The first electrode tab 232 serves as the positive electrode tab of the electrode assembly 23, and the second electrode tab 233 serves as the negative electrode tab of the electrode assembly 23. Along the wall thickness direction X, a first current collecting member 24 and a second current collecting member 27 are disposed between the wall 211 and the main body 231. The first current collecting member 24 connects the first electrode tab 232 to the first electrode terminal 22, and the second current collecting member 27 connects the second electrode tab 233 to the second electrode terminal 26, thereby electrically connecting the first electrode terminal 22 to the electrode assembly 23, and the second electrode terminal 26 to the electrode assembly 23. The connector 25 is accommodated in the housing 21. The connector 25 is separated from the first current collecting member 24 and electrically connects the wall portion 211 and the first current collecting member 24. The minimum flow area of ​​the connector 25 is smaller than the minimum flow area of ​​the first current collecting member 24. The minimum flow area of ​​the connector 25 is S1, which satisfies 2mm. 2 ≤S1≤20mm 2 .

[0323] Among them, the connecting member 25 is a conical spring arranged between the first current collecting member 24 and the wall portion 211. The two ends of the connecting member 25 in the thickness direction X of the wall portion are respectively abutted against the wall portion 211 and the first current collecting member 24. Along the thickness direction X of the wall portion, the compression ratio of the connecting member 25 is 10%-50%. The connector 25 includes a first connecting section 253, a weak section 251, and a second connecting section 254. The first connecting section 253 and the second connecting section 254 are respectively connected to the ends of the weak section 251 in the wall thickness direction X. The first connecting section 253 abuts the wall 211, and the second connecting section 254 abuts the first current collecting member 24. The cross-sectional area of ​​the first connecting section 253 and the cross-sectional area of ​​the second connecting section 254 perpendicular to the conical spring's helical direction are both greater than the cross-sectional area of ​​the weak section 251 perpendicular to the conical spring's helical direction. The cross-sectional area of ​​the weak section 251 perpendicular to the conical spring's helical direction is the minimum flow area S1 of the connector 25. The length of the weak section 251 along the conical spring's helical direction is L1, satisfying the condition 0.3 mm ≤ L1 ≤ 5 mm. The connector 25 also includes a first insulating member 252, which covers the outer side of the weak section 251. Along the thickness direction X of the wall portion, an accommodating portion 2111 is provided on the side of the wall portion 211 facing the electrode assembly 23. The first connecting section 253 of the connecting member 25 is inserted into the accommodating portion 2111 and abuts against the bottom of the accommodating portion 2111. The side surface of the accommodating portion 2111 includes a limiting surface 2111a. The limiting surface 2111a is configured to limit the connecting member 25 from detaching from the accommodating portion 2111 along the thickness direction X of the wall portion. The limiting surface 2111a is a conical surface that fits the outer circumferential surface of the conical spring. The large end of the limiting surface 2111a is farther away from the first current collecting member 24 than the small end of the limiting surface 2111a. The diameter of the large end of the limiting surface 2111a in the thickness direction X of the wall portion is D1, and the diameter of the small end of the limiting surface 2111a in the thickness direction X of the wall portion is D2, satisfying the condition that 0.5mm≤D1-D2≤5mm.

[0324] According to some embodiments of the present application, as shown in Figures 12 to 16, a battery cell 20 is provided. The battery cell 20 includes a housing 21, a first electrode terminal 22, a second electrode terminal 26, an electrode assembly 23, a first current collecting member 24, a second current collecting member 27, and a connector 25. The housing 21 has a wall portion 211. The housing 21 includes a shell 212 and an end cap 213. The interior of the shell 212 forms a receiving cavity having an opening 2121. The end cap 213 closes the opening 2121 and serves as the wall portion 211. The first electrode terminal 22 and the second electrode terminal 26 are both insulated and mounted on the wall portion 211. The electrode assembly 23 is housed within the accommodating cavity. The electrode assembly 23 includes a main body 231, a first electrode tab 232, and a second electrode tab 233. The first electrode tab 232 and the second electrode tab 233 are both connected to one end of the main body 231 that faces the wall 211 in the wall thickness direction X. The first electrode tab 232 serves as the positive electrode tab of the electrode assembly 23, and the second electrode tab 233 serves as the negative electrode tab of the electrode assembly 23. Along the wall thickness direction X, a first current collecting member 24 and a second current collecting member 27 are disposed between the wall 211 and the main body 231. The first current collecting member 24 connects the first electrode tab 232 to the first electrode terminal 22, and the second current collecting member 27 connects the second electrode tab 233 to the second electrode terminal 26, thereby electrically connecting the first electrode terminal 22 to the electrode assembly 23, and the second electrode terminal 26 to the electrode assembly 23. The connector 25 is accommodated in the housing 21. The connector 25 is integrally formed with the first current collecting member 24, and the connector 25 is electrically connected to the wall portion 211 and the first current collecting member 24. The minimum flow area of ​​the connector 25 is smaller than the minimum flow area of ​​the first current collecting member 24, and the minimum flow area of ​​the connector 25 is S1, which satisfies 2mm. 2 ≤S1≤20mm 2 .

[0325] Among them, the first current collecting component 24 and the connecting member 25 are arranged along the first direction Y, and the connecting member 25 includes a weak section 251 and a first connecting section 253. Along the first direction Y, the weak section 251 is connected between the first current collecting component 24 and the first connecting section 253. The area of ​​the cross section of the weak section 251 perpendicular to the first direction Y is the minimum flow area S1 of the connecting member 25, and the length of the weak section 251 is L2, satisfying 0.3mm≤L2≤5mm. The first connecting section 253 includes a first connecting portion 2531, a bent portion 2532, and a second connecting portion 2533 connected in sequence. The first connecting portion 2531 is connected to the weak section 251, and the second connecting portion 2533 is connected to the wall portion 211. Along the thickness direction X of the wall portion, the second connecting portion 2533 is closer to the wall portion 211 than the first connecting portion 2531, and the second connecting portion 2533 is welded to the wall portion 211. The welding area between the second connecting portion 2533 and the wall portion 211 is S2, which meets 30mm. 2 ≤S2≤100mm2 Along the wall's thickness direction X, the first connecting portion 2531 has a first surface 2531a facing the wall 211. The first current collecting member 24 has a second surface 242 facing the wall 211, flush with the first surface 2531a. The first connecting portion 2531 has a third surface 2531b facing away from the wall 211. The first current collecting member 24 has a fourth surface 243 facing away from the wall 211, flush with the third surface 2531b. Along the first direction Y, a groove 255 is formed between the first current collecting member 24 and the first connecting section 253. The bottom wall of the groove 255 forms a weak section 251. Along the second direction Z, grooves 255 are formed on both sides of the weak section 251. The first direction Y, the second direction Z, and the wall's thickness direction X are perpendicular to each other.

[0326] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0327] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, comprising: a housing having a wall portion; a first electrode terminal, insulated and mounted on the housing; an electrode assembly housed in the housing, the electrode assembly comprising a main body and a first tab, wherein the first tab is disposed on the main body; a first current collecting member disposed in the housing, the first current collecting member electrically connecting the first electrode terminal and the first electrode tab; as well as A connecting member electrically connects the wall portion and the first current collecting member, wherein a minimum flow area of the connecting member is smaller than a minimum flow area of the first current collecting member.

2. The battery cell according to claim 1, wherein: The minimum flow area of the connector is S1, which satisfies the following conditions: 2mm 2 ≤S1≤20mm 2 .

3. The battery cell according to claim 1 or 2, wherein: The connecting piece and the first current collecting member are provided separately.

4. The battery cell according to claim 3, wherein: Along the thickness direction of the wall portion, the first current collecting member is arranged between the main body and the wall portion, and the connecting member is an elastic member arranged between the first current collecting member and the wall portion. The two ends of the connecting member are respectively abutted against the first current collecting member and the wall portion to electrically connect the first current collecting member and the wall portion.

5. The battery cell according to claim 4, wherein: In the extending direction of the connecting member, a portion of the connecting member forms a weak section, and the housing is electrically connected to the first current collecting member through the weak section; The minimum flow area of the weak section is the minimum flow area S1 of the connecting piece. The battery cell according to claim 5 , wherein: Along the extending direction of the connecting piece, the length of the weak section is L1, which satisfies 0.3 mm ≤ L1 ≤ 5 mm.

7. The battery cell according to claim 5 or 6, wherein: The connecting piece further comprises: The first insulating member is wrapped around the outer side of the weak section.

8. The battery cell according to any one of claims 5 to 7, wherein: The connecting member further comprises a first connecting section, wherein the minimum flow area of the first connecting section is larger than the minimum flow area of the weak section; Wherein, along the thickness direction of the wall portion, the first connecting section is connected to an end of the weak section close to the wall portion, and the first connecting section abuts against the wall portion.

9. The battery cell according to any one of claims 5 to 8, wherein: The connecting member further comprises a second connecting section, wherein the minimum flow area of the second connecting section is greater than the minimum flow area of the weak section; Wherein, along the thickness direction of the wall portion, the second connecting section is connected to one end of the weak section close to the first current collecting member, and the second connecting section abuts against the first current collecting member.

10. The battery cell according to any one of claims 4 to 9, wherein: The connecting member is a spring, and along the thickness direction of the wall portion, two ends of the spring are respectively in contact with the first current collecting member and the wall portion.

11. The battery cell according to claim 10, wherein: Along the thickness direction of the wall portion, a receiving portion is provided on a side of the wall portion facing the electrode assembly, and a portion of the connector is inserted into the receiving portion.

12. The battery cell according to claim 11, wherein: The side surface of the accommodating portion includes a limiting surface, and the limiting surface is configured to limit the connecting member from being separated from the accommodating portion along the thickness direction of the wall portion.

13. The battery cell according to claim 12, wherein: The connecting piece is a conical spring, the limiting surface is a conical surface that fits the outer circumference of the conical spring, and along the thickness direction of the wall portion, the large end of the limiting surface is farther away from the first current collecting component than the small end of the limiting surface.

14. The battery cell according to claim 13, wherein: The diameter of the large end of the limiting surface in the thickness direction of the wall portion is D1, and the diameter of the small end of the limiting surface in the thickness direction of the wall portion is D2, satisfying 0.5mm≤D1-D2≤5mm.

15. The battery cell according to any one of claims 10 to 14, wherein: Along the thickness direction of the wall portion, the compression ratio of the connecting piece is 10%-50%.

16. The battery cell according to claim 1 or 2, wherein: The connecting piece and the first current collecting member are integrally formed.

17. The battery cell according to claim 16, wherein: The first current collecting member is disposed between the main body and the wall portion along a thickness direction of the wall portion; In which, the first current collecting component and the connecting member are arranged along a first direction, the first direction is perpendicular to the thickness direction of the wall portion, and along the first direction, part of the connecting member forms a weak section, the weak section is connected to the first current collecting component, and the minimum flow area of the weak section is the minimum flow area S1 of the connecting member.

18. The battery cell according to claim 17, wherein: Along the first direction, the length of the weak section is L2, which satisfies 0.3 mm ≤ L2 ≤ 5 mm.

19. The battery cell according to claim 17 or 18, wherein: The connecting member also includes a first connecting section, the minimum flow area of the first connecting section is greater than the minimum flow area of the weak section, the first connecting section is connected to the wall portion, the weak section connects the first connecting section and the first current collecting component, and the first current collecting component, the weak section and the first connecting section are arranged along the first direction.

20. The battery cell according to claim 19, wherein The first connecting section includes a first connecting portion, a bending portion, and a second connecting portion connected in sequence, the first connecting portion is connected to the weak section, and the second connecting portion is connected to the wall portion; Wherein, along the thickness direction of the wall portion, the second connection portion is closer to the wall portion than the first connection portion, and the second connection portion abuts against the wall portion.

21. The battery cell according to claim 20, wherein: The first connection portion has a first surface facing the wall portion in a thickness direction of the wall portion, and the first current collecting member has a second surface facing the wall portion, the second surface being flush with the first surface.

22. The battery cell according to claim 20 or 21, wherein: The first connection portion has a third surface facing away from the wall portion along a thickness direction of the wall portion, and the first current collecting member has a fourth surface facing away from the wall portion, the fourth surface being flush with the third surface.

23. The battery cell according to any one of claims 20 to 22, wherein: The second connection portion is connected to the wall portion by welding.

24. The battery cell according to claim 23, wherein: The welding area between the second connecting portion and the wall portion is S2, which satisfies 30mm 2 ≤S2≤100mm 2 .

25. The battery cell according to any one of claims 19 to 24, wherein: Along the first direction, a groove is formed between the first current collecting member and the first connecting section, and a bottom wall of the groove serves as the weak section.

26. The battery cell according to claim 25, wherein: The groove is formed on at least one side of the weak section along the second direction, and the first direction, the second direction and the thickness direction of the wall portion are perpendicular to each other.

27. The battery cell according to claim 25, wherein: The groove is formed on at least one side of the weak section along the thickness direction of the wall portion.

28. The battery cell according to any one of claims 1 to 27, wherein: The first electrode tab is the positive electrode tab of the electrode assembly.

29. The battery cell according to any one of claims 1 to 28, wherein: The first electrode terminal is insulated and mounted on the wall portion. Along the thickness direction of the wall portion, the first current collecting member is arranged between the main body and the wall portion, and the first electrode tab is arranged at one end of the main body facing the wall portion.

30. The battery cell according to any one of claims 1 to 29, wherein: The battery cell further includes a second electrode terminal and a second current collecting member, the second electrode terminal being insulated and mounted on the housing, and the second current collecting member being disposed within the housing; The electrode assembly further includes a second electrode tab, which is disposed on the main body. The second electrode tab has a polarity opposite to that of the first electrode tab, and is electrically connected to the second electrode terminal through the second current collecting member.

31. The battery cell according to any one of claims 1 to 30, wherein: The housing comprises: A housing having an opening formed therein, wherein the housing is used to accommodate the electrode assembly; an end cap for closing the opening; Wherein, the end cover is the wall portion.

32. The battery cell according to any one of claims 1 to 30, wherein: The housing comprises: The housing includes an integrally formed sidewall and the wall portion, the sidewall being disposed around the wall portion, one end of the sidewall being connected to the wall portion along the thickness direction of the wall portion, and the other end of the sidewall being enclosed to form an opening, the sidewall and the wall portion jointly defining a housing cavity for accommodating the electrode assembly; An end cap closes the opening.

33. A battery comprising the battery cell according to any one of claims 1 to 32.

34. The battery according to claim 33, wherein The battery further comprises: A battery management system is electrically connected to the wall portion, and the battery management system is configured to issue an early warning when the connector is fused.

35. An electrical device comprising the battery cell according to any one of claims 1 to 32, wherein the battery cell is used to provide electrical energy.

Images