Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device, and belongs to the technical field of batteries. Wherein the battery monomer comprises a shell, a first electrode terminal, an electrode assembly, a first current collecting component and a connecting piece. The housing has a wall portion. The first electrode terminal is mounted to the housing in an insulated manner. The electrode assembly is contained in the shell and comprises a main body part and a first tab, and the first tab is arranged on the main body part. The first current collecting component is arranged in the shell; the first current collecting component is electrically connected with the first electrode terminal and the first tab; the connecting piece is electrically connected with the wall part and the first current collecting component, and the minimum flow passing area of the connecting piece is smaller than the minimum flow passing area of the first current collecting component. According to the invention, the first current collecting component is arranged on the connecting piece, so that the heat generated by the connecting piece when the battery monomers are short-circuited is higher and the heat is gathered faster, the connecting piece can be fused prior to the first current collecting component, a short-circuit path can be cut off, the phenomena of damage to the information acquisition equipment and the like can be relieved, and the use reliability of the battery monomers can be improved.

Description

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 developed by leaps and bounds. In the field of electric vehicles, 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. Among them, batteries, as core components of new energy vehicles, have high requirements in terms of reliability and service life.

[0003] In battery technology, in order 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 information collection equipment of existing battery cells is very likely to be damaged during the performance monitoring process, and the battery cells are very prone to short circuit risks, resulting in low reliability of the battery cells. Utility Model Content

[0004] 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.

[0005] 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 connecting member; the shell has a wall portion; the first electrode terminal is insulated and installed on the shell; the electrode assembly is accommodated in the shell, the electrode assembly comprises a main body portion and a first pole ear, the first pole ear 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 pole ear; the connecting member electrically connects the wall portion and the first current collecting member, and the minimum flow area of ​​the connecting member is smaller than the minimum flow area of ​​the first current collecting member.

[0006] 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, so that the connector 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 the short-circuit path can be cut off, so as to alleviate the damage of the information collection equipment, and can effectively reduce the use risk caused by the battery cell further, which is conducive to improving the reliability of the battery cell.

[0007] In some embodiments, the minimum flow area of ​​the connector is S 1 , meet, 2mm 2 ≤S 1 ≤20mm 2 .

[0008] 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 the connector takes too long 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, which can further alleviate the phenomenon of damage to the information collection equipment and is conducive to further improving 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.

[0009] In some embodiments, the connecting member and the first current collecting member are provided separately.

[0010] In the above technical solution, by arranging the connecting piece and the first current collecting member as a separate structure, on the one hand, it is convenient to separately process and form the connecting piece and the first current collecting member, so that the production process of the connecting piece 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 piece during the use of the battery cell, which is beneficial to reduce the later maintenance cost of the battery cell.

[0011] 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 both 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.

[0012] In the above technical solution, the connecting member is set 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, so that the connecting member is electrically connected to the first current collecting member and the wall portion, the structure is simple, and it is easy to assemble.

[0013] 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 S of the connector. 1 .

[0014] 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 fused. 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, and on the other hand, the fuse position of the connector can be controlled, and the fuse 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.

[0015] In some embodiments, along the extension direction of the connecting member, the length of the weak section is L 1 , meet, 0.3mm≤L 1 ≤5mm.

[0016] 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 overlapping of the weak section of the connector after melting, so as to reduce the risk of overlapping 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 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 overlapping of the weak section of the connector after melting, but also effectively save the space occupied by the weak section of the connector.

[0017] In some embodiments, the connecting member further includes a first insulating member; the first insulating member is coated on the outer side of the weak section.

[0018] In the above technical solution, by covering the first insulating member on the outside of the weak section of the connector, 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 bump, which is beneficial to improving the service life of the connector. On the other hand, since the connector is an elastic member with 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 is melted when a short circuit occurs in the battery cell, so as to reduce the phenomenon of the weak section overlapping with the wall or the first current collecting component under the elastic force of the connector after it is melted, thereby reducing the risk of overlapping between the weak section of the connector and other components after it is melted.

[0019] In some embodiments, the connecting member also includes a first connecting section, and 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 an end of the weak section close to the wall portion, and the first connecting section abuts against the wall portion.

[0020] 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 fused 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.

[0021] In some embodiments, the connecting member also includes a second connecting section, and 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.

[0022] 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 fused at 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 beneficial to improving the flow area between the connector and the first current collecting component.

[0023] In some embodiments, 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.

[0024] In the above technical solution, by setting the connecting piece as a spring abutting between the first current collecting component and the wall portion, the connecting piece with such a structure is easy to assemble, which is beneficial to reduce 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, so as to improve the assembly stability of the connecting piece.

[0025] 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.

[0026] 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 against 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, so as to improve 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, so as to reduce the shaking of the connector during use.

[0027] In some embodiments, the side surface of the accommodating portion includes a limiting surface, and the limiting surface is configured to limit the connection member from being separated from the accommodating portion along the thickness direction of the wall portion.

[0028] In the above technical solution, a limited surface is formed on the side of the accommodating portion, and the limited surface can limit the connection piece from detaching 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, so as to reduce the risk of connection failure between the wall portion and the first current collecting component.

[0029] In some embodiments, the connecting member is a conical spring, the limiting surface is a conical surface that matches the outer circumferential 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.

[0030] In the above technical solution, the connecting piece is set as a conical spring so that the connecting piece 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 piece, and the small end of the limiting surface is located between the large end of the limiting surface and the first current collecting member in the thickness direction of the wall portion, so that after the connecting piece is inserted into the accommodating portion, the limiting surface of the accommodating portion can limit the connecting piece to restrict the connecting piece in the accommodating portion. The structure is simple and easy to manufacture.

[0031] In some embodiments, the diameter of the large end of the limiting surface in the thickness direction of the wall portion is D 1 The diameter of the small end of the limiting surface in the thickness direction of the wall is D 2 , meet, 0.5mm≤D 1 -D 2 ≤5mm.

[0032] In the above technical scheme, 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 connecting piece is improved, so as to further reduce the phenomenon of the connecting piece being separated 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 excessive difficulty in assembling the connecting piece into the accommodating portion is alleviated, which is beneficial to reducing the difficulty of assembly between the connecting piece 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 connecting piece, but also reduce the difficulty of inserting the connecting piece into the accommodating portion.

[0033] In some embodiments, along the thickness direction of the wall portion, the compression ratio of the connecting member is 10%-50%.

[0034] In the above technical scheme, the compression ratio of the spring serving as the connecting piece before assembly and after being assembled between the wall portion and the first current collecting component is 10% to 50%. On the one hand, the compression ratio of the connecting piece is set to be greater than or equal to 10% to enhance the effect of the connecting piece abutting against the wall portion and the first current collecting component, and is beneficial to enhancing the structural stability of the connecting piece when assembled between the wall portion and the first current collecting component. On the other hand, the compression ratio of the connecting piece is set to be less than or equal to 50% to alleviate the phenomenon of plastic deformation caused by excessive compression of the connecting piece, thereby facilitating improving the service life of the connecting piece. Therefore, setting the compression ratio of the connecting piece to 10% to 50% can not only take into account the better abutment effect of the connecting piece with the wall portion and the first current collecting component, but also alleviate the phenomenon that the connecting piece cannot recover elastic deformation due to excessive compression.

[0035] In some embodiments, the connecting piece is integrally formed with the first current collecting member.

[0036] 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.

[0037] In some embodiments, along the thickness direction of the wall portion, the first current collecting member is disposed between the main body portion and 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 S of the connecting member. 1 .

[0038] 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 fused. 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 pole ear, and facilitates the manufacturing of the first current collecting member and the connector, has a simple structure, and is easy to manufacture. On the other hand, the fuse position of the connector can be controlled, and the fuse position can be controlled at the portion 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 beneficial to reducing the difficulty of assembling the connector.

[0039] In some embodiments, along the first direction, the length of the weak section is L 2 , meet, 0.3mm≤L 2 ≤5mm.

[0040] 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 risk of overlapping 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.

[0041] 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 member, and the first current collecting member, the weak section and the first connecting section are arranged along the first direction.

[0042] In the above technical solution, the connector is also 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 fused at 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 improve the flow area between the connector and the wall portion.

[0043] 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.

[0044] In the above technical solution, the first connecting section is provided with a first connecting portion, a bending portion and a second connecting portion which are connected in sequence, the first connecting portion is connected to the first current collecting member 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 member through the connecting piece, wherein 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, so that the first connecting section with such a structure can compensate for the gap between the first current collecting member and the wall portion in the thickness direction of the wall portion, which can improve the connection stability and connection reliability between the first connecting section of the connecting piece and the wall portion on the one hand, and is beneficial to improving the assembly quality between the connecting piece and the wall portion, and on the other hand, there is no need to arrange other components to compensate for the gap between the first current collecting member and the wall portion in the thickness direction of the wall portion, which is beneficial to reducing the difficulty of assembly between the connecting piece and the wall portion, so as to improve the production efficiency of the battery cell.

[0045] 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, and the second surface is flush with the first surface.

[0046] 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.

[0047] 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, and the fourth surface is flush with the third surface.

[0048] 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 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.

[0049] In some embodiments, the second connection portion is connected to the wall portion by welding.

[0050] 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 connection failure 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.

[0051] In some embodiments, the welding area between the second connecting portion and the wall portion is S 2 , meet, 30mm 2 ≤S 2 ≤100mm 2 .

[0052] 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 30 mm 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, so as to improve 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, so as to effectively reduce the assembly difficulty between the connecting part and the wall part, which is beneficial to improve the production efficiency of the battery monomer and reduce the production cost of the battery monomer. Therefore, the welding area between the second connecting part and the wall part 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 assembly between the connecting piece and the wall portion.

[0053] 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 is the weak section.

[0054] 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, which has a simple structure and is easy to process and form.

[0055] 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.

[0056] 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 to form a weak section on the bottom wall of the groove. The structure is simple and easy to process.

[0057] In some embodiments, along the thickness direction of the wall portion, the groove is formed on at least one side of the weak section.

[0058] 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.

[0059] In some embodiments, the first electrode tab is a positive electrode tab of the electrode assembly.

[0060] 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 adopting this structure can effectively alleviate the phenomenon of electrical corrosion of the outer shell of the battery cell, which is beneficial to improve the service life of the battery cell and reduce the risk of leakage of the battery cell during use.

[0061] 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.

[0062] 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.

[0063] In some embodiments, the battery cell further includes a second electrode terminal and a second current collecting member, wherein the second electrode terminal is insulated and mounted on the outer shell, and the second current collecting member is disposed in the outer shell; wherein the electrode assembly further includes a second pole ear, wherein the second pole ear is disposed on the main body, the second pole ear has an opposite polarity to the first pole ear, and the second pole ear is electrically connected to the second electrode terminal through the second current collecting member.

[0064] In the above technical solution, the battery cell is also provided with a second electrode terminal and a second current collecting member, and 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 connecting member.

[0065] In some embodiments, the outer shell 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.

[0066] In the above technical solution, by setting the wall of the shell as an end cover for closing the opening of the shell, the battery cell adopting this structure is convenient for connecting the connector to the wall of the shell, which is beneficial to reduce the difficulty of assembling the battery cell and improve the production efficiency of the battery cell.

[0067] In some embodiments, the 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, 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, the side wall and the wall portion jointly define a accommodating cavity for accommodating the electrode assembly; the end cover closes the opening.

[0068] In the above technical solution, by setting the wall portion of the outer shell as a wall of the shell that is arranged opposite to the end cover in the thickness direction of the wall portion, the battery cell adopting this structure can make the wall portion used to connect with the connecting piece 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 connecting piece, which is beneficial to improving the service life of the connecting piece, 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, which is beneficial to further reduce the risk of leakage of the battery cell during use.

[0069] In a second aspect, an embodiment of the present application further provides a battery, comprising the above-mentioned battery cell.

[0070] 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.

[0071] 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 fuse, so as to issue an early warning reminder 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 beneficial to improving the reliability of the battery.

[0072] 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

[0073] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. 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 related drawings can be obtained based on these drawings without paying creative work.

[0074] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0075] Figure 2 An exploded view of the structure of a battery provided in some embodiments of the present application;

[0076] Figure 3 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0077] Figure 4An exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0078] Figure 5 A cross-sectional view of a battery cell provided for some embodiments of the present application;

[0079] Figure 6 for Figure 5 A partial enlarged view of the battery cell at A shown;

[0080] Figure 7 A cross-sectional view of a connector of a battery cell provided in some embodiments of the present application;

[0081] Figure 8 for Figure 7 A partial enlarged view of the B portion of the connecting member shown;

[0082] Fig. 9 A partial cross-sectional view of a connector of a battery cell provided in some embodiments of the present application in other embodiments;

[0083] Fig.10 A schematic diagram of assembling a wall portion and a connector of a battery cell provided in some embodiments of the present application;

[0084] Fig.11 A partial cross-sectional view of a wall portion of a battery cell provided in some embodiments of the present application;

[0085] Fig.12 An exploded view of the structure of a battery cell provided in some other embodiments of the present application;

[0086] Fig.13 A cross-sectional view of a battery cell provided in some other embodiments of the present application;

[0087] Fig.14 for Fig.13 A partial enlarged view of the battery cell at position C shown;

[0088] Fig.15 A schematic diagram of connection between a connector of a battery cell and a first current collecting member provided in some other embodiments of the present application;

[0089] Fig.16 A cross-sectional view of a battery cell connector provided by some other embodiments of the present application being connected to a first current collecting member;

[0090] Fig.17 A schematic diagram of a connection between a connector of a battery cell and a first current collecting member in other embodiments provided by yet other embodiments of the present application;

[0091] Fig.18 Cross-sectional views of other embodiments of the battery cells provided in some other embodiments of the present application in which the connecting members are connected to the first current collecting members.

[0092] Icon: 1000-vehicle; 100-battery; 10-box; 11-first box body; 12-second box body; 20-battery cell; 21-housing; 211-wall; 2111-accommodating portion; 2111a-limiting surface; 212-housing; 2121-opening; 213-end cover; 22-first electrode terminal; 23-electrode assembly; 231-main body; 232-first pole ear; 233-second pole ear; 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

[0093] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0094] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. 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 and secondary relationship.

[0095] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0096] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0097] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0098] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0099] The term "plurality" used in the present application refers to two or more (including two).

[0100] 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.

[0101] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0102] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and removed between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting, while allowing active ions to pass through.

[0103] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet 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.

[0104] 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 disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0105] 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 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.).

[0106] 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 positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also referred to as LFP), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), 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 LiCoO 2 ), lithium nickel oxide (such as LiNiO 2 ), lithium manganese oxide (such as LiMnO 2 、LiMn 2 O 4 ), 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 O 2 (Also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O 2 (Also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O 2 (Also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O 2 (Also referred to as NCM 622 )、LiNi0.8 Co 0.1 Mn 0.1 O 2 (Also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O 2 ) and at least one of its modified compounds.

[0107] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. When the foamed metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the foamed metal, but of course, the positive electrode active material may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is lithium metal and / or a lithium-rich material.

[0108] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0109] As an example, the negative electrode current collector may be a metal foil, a foamed metal 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 foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. The composite current collector may include a polymer material base 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.).

[0110] 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.

[0111] 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 disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0112] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells 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.

[0113] 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.

[0114] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0115] In some embodiments, the separator is a separator membrane. There may be many types of separator membranes, and any known porous separator membrane with good chemical stability and mechanical stability may be selected.

[0116] As an example, the material of the separator may include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or may be attached to the surface of the positive and negative electrodes.

[0117] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0118] In some embodiments, the battery cell further includes an electrolyte, which plays a role in conducting ions between the positive and negative electrodes. The electrolyte can be liquid, gel or solid. Among them, the liquid electrolyte includes an electrolyte salt and a solvent.

[0119] 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 dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0120] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl 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.

[0121] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0122] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0123] 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, and the like.

[0124] 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.

[0125] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0126] 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.

[0127] In some embodiments, the electrode assembly is a laminate structure.

[0128] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0129] 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.

[0130] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0131] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0132] As an example, the separator may be disposed continuously, and disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0133] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0134] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0135] In some embodiments, the 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 (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0136] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes but is not limited to a square-shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc.

[0137] 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.

[0138] 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.

[0139] 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 accommodated in the case.

[0140] 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.

[0141] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0142] Batteries have outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient. They are an important part of the development of new energy today. The development of battery technology must consider many design factors at the same time, such as energy density, cycle life, discharge capacity, charge and discharge rate and other performance parameters. In addition, the safety of the battery also needs to be considered.

[0143] For a general battery cell, the battery cell usually includes a shell, an electrode assembly, two electrode terminals and two current collecting components. The electrode assembly is accommodated in the shell, and the two electrode terminals are arranged on the shell, and the two electrode terminals are respectively connected to the positive and negative ears of the electrode assembly through two current collecting components to realize the input or output of the positive and negative electrodes of the battery cell, and the use of the battery cell can be monitored by connecting the information collection device to the electrode terminals. In order to reduce the difficulty of connecting the information collection device to the battery cell and reduce the difficulty of data collection, in the related art, the shell of the battery cell is connected to an ear of the electrode assembly through a current collecting component, so that the shell of the battery cell is positively charged or negatively charged, so that the use information of the battery cell can be collected by connecting the information collection device to the shell of the battery cell, which is conducive to reducing the difficulty of assembling and arranging the information collection device. However, the battery cell of this structure is very likely to have the phenomenon that the ears with different polarities overlap with the shell, so as to cause the risk of overlapping short circuit of the battery cell, and then it is very easy to cause damage to the information collection device, and the battery cell has a greater use risk, which is not conducive to improving the reliability of the use of the battery cell.

[0144] Based on the above considerations, in order to solve the problem of low reliability of battery cells, an embodiment of the present application provides a battery cell, which includes 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 on the housing. The electrode assembly is accommodated in the housing, and the electrode assembly includes a main body and a first pole ear, and the first pole ear is arranged on the main body. The first current collecting member is arranged in the housing, and the first current collecting member is electrically connected to the first electrode terminal and the first pole ear. 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.

[0145] 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 the short-circuit path can be cut off, so as to alleviate the damage of the information collection equipment, and can effectively reduce the use risk caused by the battery cell further, which is conducive to improving the reliability of the battery cell.

[0146] The battery cells disclosed in the embodiments of the present application can be used, but not limited to, in electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery cells and batteries disclosed in the present application can be used to form the electrical device, which is helpful to alleviate the use risk caused by the internal overlap short circuit of the battery cells, so as to improve the use reliability of the battery cells.

[0147] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, 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., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0148] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0149] Please refer to Figure 1 , Figure 1A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided 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 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source or a power source for the vehicle 1000, etc. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for the starting, navigation and working power requirements of the vehicle 1000 during driving.

[0150] In some embodiments of the present application, the battery 100 can not only serve as an operating power source or a use power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0151] Please refer to Figure 2 and Figure 3 , Figure 2 The structure explosion diagram of the battery 100 provided in some embodiments of the present application is shown in FIG. Figure 3 The schematic diagram of the structure of the battery cell 20 provided in some embodiments of the present application is as follows: The battery 100 comprises a box body 10 and a battery cell 20 , and the battery cell 20 is used to be accommodated in the box body 10 .

[0152] The box body 10 is used to provide an assembly space for the battery cell 20, and the box body 10 can adopt a variety of structures. 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 cell 20. The second box body 12 may be a hollow structure with one end open, and the first box body 11 may 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 may 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.

[0153] 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. Figure 2 In the embodiment, the box body 10 is in the shape of a rectangular parallelepiped.

[0154] In the battery 100, the battery cell 20 disposed in the box 10 may be one or more. When there are more than one battery cell 20 disposed in the box 10, the multiple battery cells 20 may be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 20 may be accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in mixed connection, and then the multiple battery modules may be connected in series, in parallel, or in mixed connection to form a whole, and then the whole may be accommodated in the box 10.

[0155] 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 plurality of battery cells 20 to achieve electrical connection between the plurality of battery cells 20 .

[0156] Each battery cell 20 may be a secondary battery or a primary battery; it may also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be in a rectangular parallelepiped, a cylinder, a prism or other shapes. For example, Figure 3 In the figure, the battery cell 20 is a rectangular parallelepiped structure.

[0157] According to some embodiments of the present application, referring to Figure 3 , and please refer to Figure 4 , Figure 5 and Figure 6 , Figure 4 This is an exploded view of the structure of the battery cell 20 provided in some embodiments of the present application. Figure 5 A cross-sectional view of a battery cell 20 provided in some embodiments of the present application, Figure 6 for Figure 5 A partial enlarged view of the battery cell 20 at A shown in the figure. The present application provides a battery cell 20, which includes a shell 21, a first electrode terminal 22, an electrode assembly 23, a first current collecting member 24 and a connector 25. The shell 21 has a wall portion 211. The first electrode terminal 22 is insulated and mounted on the shell 21. The electrode assembly 23 is accommodated in the shell 21, and the electrode assembly 23 includes a main body 231 and a first pole ear 232, and the first pole ear 232 is arranged on the main body 231. The first current collecting member 24 is arranged in the shell 21, and the first current collecting member 24 electrically connects the first electrode terminal 22 and the first pole ear 232. The connector 25 electrically connects the wall portion 211 and the first current collecting member 24, and the minimum flow area of ​​the connector 25 is smaller than the minimum flow area of ​​the first current collecting member 24.

[0158] The housing 21 can also be used to contain electrolyte, such as electrolyte. The housing 21 can be in various structural forms. The housing 21 can also be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0159] In some embodiments, the housing 21 may include a shell 212 and an end cap 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 cap 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.

[0160] Optionally, the wall portion 211 for connecting with the connecting member 25 may be an end cover 213, or may be one of the multiple walls of the housing 212. Figure 3 and Figure 4 In the embodiment, the wall portion 211 is the end cover 213 of the shell 21. Of course, in other embodiments, the wall portion 211 can also be the bottom wall of the shell 212 arranged opposite to the end cover 213 in the thickness direction X of the wall portion, or the side wall adjacent to and abutting against the end cover 213.

[0161] 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 .

[0162] Optionally, the shell 212 can be in various shapes, such as a cylinder, a cuboid, etc. The shape of the shell 212 can be determined according to the specific shape of the electrode assembly 23. For example, if the electrode assembly 23 is a cylindrical structure, the shell 212 can be a cylindrical structure; if the electrode assembly 23 is a cuboid structure, the shell 212 can be a cuboid structure. Of course, the end cap 213 can also be in various structures, such as a plate-like structure or a hollow structure with one end open. For example, in Figure 4 In the embodiment, the shell 212 is a rectangular parallelepiped structure, and the end cover 213 is a plate-like structure.

[0163] It is understandable that the outer shell 21 is not limited to the above structure, and the outer shell 21 may also be other structures. For example, the outer shell 21 includes a shell body 212 and two end caps 213. The shell body 212 is a hollow structure with openings 2121 on opposite sides. One end cap 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.

[0164] 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 a positive electrode sheet, an isolation member, and a negative electrode sheet, or it can be a stacked structure formed by stacking a positive electrode sheet, an isolation member, and a negative electrode sheet.

[0165] Exemplarily, the isolation member 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.

[0166] The electrode assembly 23 includes a main body 231 and a first pole tab 232. The first pole tab 232 is disposed on the main body 231. The main body 231 is the main part of the electrode assembly 23 for electrochemical reaction in the battery cell 20. The first pole tab 232 plays the role of inputting or outputting the positive electrode or negative electrode of the electrode assembly 23. The first pole tab 232 is electrically connected to the first electrode terminal 22 to achieve electrical connection between the electrode assembly 23 and the first electrode terminal 22. It should be noted that the first pole tab 232 of the electrode assembly 23 is a component formed by mutually stacking and connecting the regions on the positive electrode sheet that are not coated with the positive electrode active material layer or a component formed by mutually stacking and connecting the regions on the negative electrode sheet that are not coated with the negative electrode active material layer. If the first pole ear 232 is used to output the positive electrode of the electrode assembly 23, that is, the first pole ear 232 is the positive pole ear of the electrode assembly 23, then the first pole ear 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 ear 232 is used to output the negative electrode of the electrode assembly 23, that is, the first pole ear 232 is the negative pole ear of the electrode assembly 23, then the first pole ear 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.

[0167] Optionally, the number of electrode assemblies 23 contained in the housing 21 may be one or more. Figure 4 In the embodiment, the housing 21 of the battery cell 20 is provided with two electrode assemblies 23, and the two electrode assemblies 23 are stacked along the second direction Z. The first direction Y, the second direction Z and the thickness direction X of the wall 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 is the height direction of the battery cell 20. Of course, in other embodiments, the electrode assemblies 23 accommodated in the housing 21 can be one, three, four, five, six, seven or eight, etc.

[0168] In the embodiment of the present application, the first electrode terminal 22 serves to output or input the electrical energy of the battery cell 20. One end of the first electrode terminal 22 is used to be electrically connected to the first pole 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 the electrical energy of the battery cell 20.

[0169] 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 is welded or abutted to the first electrode tab 232, 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 to 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.

[0170] It should be noted that the first electrode terminal 22 is insulated and installed on the housing 21, that is, there is no electrical connection between the first electrode terminal 22 and the housing 21. The first electrode terminal 22 can be installed on the housing 21 in various structures. The first electrode terminal 22 can be installed on the end cap 213 or on the housing 212. For example, Figure 3 and Figure 4 In the embodiment, the first electrode terminal 22 is insulated and mounted on the end cover 213 , that is, the first electrode terminal 22 is insulated and mounted on the wall portion 211 of the housing 21 .

[0171] Exemplarily, the first electrode terminal 22 may be made of a variety of materials. For example, the first electrode terminal 22 may be made of copper, iron, aluminum, steel, or aluminum alloy.

[0172] 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 , so as to achieve electrical connection between the electrode assembly 23 and the first electrode terminal 22 .

[0173] For example, in Figure 4 and Figure 5 In the embodiment, 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 .

[0174] Among them, see Figure 4 As shown, 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.

[0175] Exemplarily, 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 a structure such as abutting against the first electrode terminal 22, and similarly, the first current collecting member 24 may also be in a structure such as abutting against the first electrode tab 232.

[0176] Exemplarily, the material of the first current collecting member 24 may be various, for example, the material of the first current collecting member 24 may be copper, iron, aluminum, steel, aluminum alloy, etc.

[0177] exist Figure 4 In the embodiment, 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 installed on the outer shell 21, and the second current collecting member 27 is arranged between the main body 231 and the wall 211 along the thickness direction X of the wall. Correspondingly, the electrode assembly 23 also includes a second pole ear 233, the second pole ear 233 is arranged on the main body 231, and the polarity of the second pole ear 233 is opposite to the polarity 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 to realize the input or output of the positive and negative electrodes of the battery cell 20.

[0178] The second electrode terminal 26 may be arranged on the housing 21 in various structures. The second electrode terminal 26 may be installed on the end cap 213 or on the housing 212. For example, Figure 3 and Figure 4 In the embodiment, the second electrode terminal 26 is insulated and mounted on the end cover 213 , that is, the second electrode terminal 26 is insulated and mounted on the wall portion 211 of the housing 21 .

[0179] Exemplarily, the first pole tab 232 and the second pole 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 pole tab 232 and the second pole tab 233 are spaced apart along the first direction Y so that the first pole tab 232 and the second pole 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.

[0180] Alternatively, see Figure 4 As shown, the second current collecting member 27 is provided with a second protrusion 271 on one 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 such a structure is conducive to reducing the difficulty of connecting the second current collecting member 27 and the second electrode terminal 26.

[0181] Exemplarily, 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 a structure such as abutting against the second electrode terminal 26, and similarly, the second current collecting member 27 may also be in a structure such as abutting against the second electrode tab 233.

[0182] The connector 25 serves to connect the first current collecting member 24 and the wall portion 211, so that the wall portion 211 of the battery cell 20 can carry the same charge as the first electrode tab 232, thereby facilitating the information collection device to obtain the usage information of the battery cell 20 after being connected to the housing 21. It should be noted that when the information collection device needs to collect data on the usage of the battery cell 20, the two input poles of the information collection device are respectively connected to the wall portion 211 of the housing 21 and the second electrode terminal 26 to collect the usage data of the battery cell 20.

[0183] 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, abutment, etc. Similarly, the connection structure between the connector 25 and the first current collecting member 24 can also be various. For example, in Figure 4 and Figure 6 In the embodiment, the connecting member 25 and the first current collecting member 24 are separately arranged structures, that is, the connecting member 25 and the first current collecting member 24 are split structures, and the connecting member 25 can be connected to the first current collecting member 24 by welding connection or abutment structure. Of course, in other embodiments, the connecting member 25 and the first current collecting member 24 can also be an integrally formed structure, that is, the connecting member 25 and the first current collecting member 24 are an integral structure, and the connecting member 25 and the first current collecting member 24 can be made by an integral forming process such as stamping or casting.

[0184] 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 component 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 component 24. That is to say, 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 flow direction of the current is the minimum flow area of ​​the connector 25.

[0185] 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.

[0186] 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 the 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 flows the current, the area of ​​the minimum cross-section of the first current collecting member 24 perpendicular to the flow direction of the current.

[0187] 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.

[0188] That is, on 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.

[0189] It should be noted that, on the current flow path, the area of ​​the minimum cross section of the connector 25 for current to pass through is smaller than the area of ​​the minimum cross section 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 pole ear 233 of the electrode assembly 23 overlaps with the shell 21 to cause a short circuit in the battery cell 20, according to the heat formula (Q = I 2 Rt), it can be known 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 component 24, and the heat accumulation speed is faster than that of the first current collecting component 24. As a result, when the second pole ear 233 and the shell 21 overlap each other to 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 component 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.

[0190] Exemplarily, the material of the connection member 25 is the same as that of the first current collecting member 24 . For example, the material of the connection member 25 may be copper, iron, aluminum, steel, aluminum alloy, or the like.

[0191] In some embodiments, see Figure 4 , Figure 5 and Figure 6 As shown, the battery cell 20 may further include a second insulating member 28. Along the thickness direction X of the wall, the second insulating member 28 is arranged on the side of the wall 211 facing the electrode assembly 23. The second insulating member 28 is configured to insulate and isolate the wall 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 211.

[0192] The second insulating member 28 is provided with an avoidance hole 281 for the connecting member 25 to pass through. The avoidance hole 281 penetrates 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 .

[0193] Exemplarily, the second insulating member 28 may be made of various materials, such as rubber, silicone or plastic.

[0194] In some embodiments, see Figure 3 and Figure 4 As shown, the battery cell 20 may further include a pressure relief mechanism 29 , which is disposed 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.

[0195] Optionally, the pressure relief mechanism 29 may be disposed on the end cover 213 of the housing 21, or may be disposed on the shell 212 of the housing 21. Figure 3 and Figure 4 In the embodiment, the pressure relief mechanism 29 is arranged on the end cover 213 .

[0196] Similarly, the pressure relief mechanism 29 and the housing 21 may be an integrally formed structure or a separately arranged structure. Figure 4 In the embodiment, the pressure relief mechanism 29 and the housing 21 are of a split structure, and the pressure relief mechanism 29 can be connected to the housing 21 by welding or the like, and correspondingly, the pressure relief mechanism 29 can be a pressure relief component such as an explosion-proof valve, an explosion-proof disk, an air valve, a pressure relief valve or a safety valve. Of course, in other embodiments, the pressure relief mechanism 29 and the housing 21 can also be an integrally formed structure, and the pressure relief mechanism 29 is an area on the housing 21 where a weak structure is formed, for example, an area on the housing 21 where a notch groove is provided.

[0197] In the present 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 housing 21 are connected by the connector 25, so that the positive electrode or the negative electrode of the electrode assembly 23 can be electrically connected to the housing 21, so that the information acquisition device can collect the usage information of the battery cell 20 after being electrically connected to the housing 21, thereby facilitating the information acquisition device to connect the battery cell 20 and collect data, which is conducive to reducing the difficulty of data collection 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 to pass is smaller than the minimum cross-sectional area of ​​the first current collecting member 24 on the path for current to pass, the connector 25 can be connected to the housing 21. 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 outer shell 21 overlap and short-circuit occurs and the heat accumulates faster, so that the connector 25 can be melted preferentially compared with the first current collecting component 24 when the electrode assembly 23 inside the battery cell 20 and the outer 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 outer shell 21 after a short circuit occurs, and then the short-circuit path can be cut off, so as to alleviate the damage of the information collection equipment, and can effectively reduce the further use risk of the battery cell 20, which is conducive to improving the use reliability of the battery cell 20.

[0198] According to some embodiments of the present application, the minimum flow area of ​​the connecting member 25 is S 1 , meet, 2mm 2 ≤S 1 ≤20mm 2 That is, on the path of the connecting member 25 for current flow, the area of ​​the minimum cross section of the connecting member 25 perpendicular to the flow direction of the current is 2 mm 2 Up to 20mm 2 .

[0199] For example, the minimum flow area S of the connecting member 25 is 1 Can be 2mm 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 、11mm2 , 12mm 2 , 15mm 2 、16mm 2 、18mm 2 or 20mm 2 wait.

[0200] In this embodiment, by setting the minimum flow area of ​​the connecting member 25 to 2 mm 2 Up to 20mm 2 On the one hand, the minimum flow area of ​​the connecting piece 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 the connector 25 being accidentally broken 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 to make the connector 25 easier 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 is conducive to 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, the connector 25 can also be quickly blown when a short circuit occurs in the battery cell 20 .

[0201] According to some embodiments of the present application, referring to Figure 4 , Figure 5 and Figure 6 , and please refer to Figure 7 , Figure 7 This 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 disposed separately from the first current collecting member 24 .

[0202] 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 .

[0203] Optionally, in the embodiment where the connector 25 and the first current collecting member 24 are separately provided, 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 structure 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.

[0204] For example, see Figure 6 and Figure 7 As shown, the connecting member 25 is a spring disposed in the housing 21, and the two ends of the spring in the thickness direction X of the wall portion are respectively in contact with the first current collecting member 24 and the wall portion 211, so that the first current collecting member 24 is electrically connected to the wall portion 211 through the connecting member 25. It should be noted that in the embodiment where the connecting member 25 is a spring, the minimum flow area S of the connecting member 25 is 1 It is the area of ​​the smallest cross section of the spring perpendicular to its spiral direction.

[0205] In this embodiment, by configuring the connector 25 and the first current collecting component 24 as a separate structure, on the one hand, it is convenient to separately process and form the connector 25 and the first current collecting component 24, so that the production processes of the connector 25 and the first current collecting component 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, during the use of the battery cell 20, it is convenient to replace or maintain the connector 25, which is beneficial to reduce the later maintenance cost of the battery cell 20.

[0206] According to some embodiments of the present application, see Figure 4 , Figure 6 and Figure 7 As shown, 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, and 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.

[0207] The connecting member 25 is an elastic member disposed between the first current collecting member 24 and the wall portion 211. The connecting member 25 may have various structures. For example, the connecting member 25 may be a spring, a V-shaped spring sheet, or a C-shaped spring sheet disposed between the first current collecting member 24 and the wall portion 211. Figure 6 and Figure 7 In the embodiment, the connecting member 25 is a spring disposed between the first current collecting member 24 and the wall portion 211 , the spiral center line of the spring extends along the thickness direction X of the wall portion, and the two ends of the spring in the thickness direction X of the wall portion abut against the first current collecting member 24 and the wall portion 211 respectively.

[0208] 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, the structure is simple, and it is easy to assemble.

[0209] According to some embodiments of the present application, referring to Figure 7 , and please refer to Figure 8 , Figure 8 for Figure 7 The partial enlarged view of the B portion of the connector 25 is shown. 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 through the weak section 251. The minimum flow area of ​​the weak section 251 is the minimum flow area S of the connector 25. 1 .

[0210] The extending direction of the connecting member 25 is the direction in which the current flows through the connecting member 25. Figure 7 In the embodiment, 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 or a C-shaped spring, the extending direction of the connecting member 25 is the extending direction of the length of the spring.

[0211] Part of the connector 25 forms a weak section 251, that is, in the extension direction of the connector 25 or on the path of the connector 25 for current flow, the connector 25 forms a weak portion, which is the weak section 251, so that the wall portion 211 and the first current collecting member 24 are electrically connected to each other through the weak section 251 of the connector 25, that is, the current flow between the wall portion 211 and the first current collecting member 24 will pass through the weak section 251 of the connector 25, so that the area of ​​the cross section of the weak section 251 perpendicular to the extension direction of the connector 25 is the minimum flow area S of the connector 25. 1 That is to say, the weak section 251 of the connecting member 25 is the minimum flow area of ​​the connecting member 25 , and the area of ​​the cross section of the weak section 251 perpendicular to the extending direction of the connecting member 25 is the minimum flow area of ​​the connecting member 25 .

[0212] For example, see Figure 7 and Figure 8 As shown, 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.

[0213] In the present embodiment, the connector 25 forms a weak section 251 in the portion in the extension direction thereof, 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 setting the weak section 251 on the connector 25, the minimum flow area of ​​the connector 25 can be smaller than the minimum flow area of ​​the first pole ear 232, and the structure is simple and easy to manufacture. On the other hand, the fuse position of the connector 25 can be controlled, and the fuse 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 beneficial to reduce the difficulty of assembling the connector 25.

[0214] According to some embodiments of the present application, see Figure 7 As shown, along the extension direction of the connecting member 25, the length of the weak section 251 is L 1 , meet, 0.3mm≤L 1 ≤5mm.

[0215] The length L of the weak section 251 is 1 The length of the weak section 251 on the path of the connecting member 25 for current flow is L. 1 For example, in Figure 7 In the embodiment, the connecting member 25 is a spring, and the spring is formed with a weak area with a reduced wire diameter, which is the weak section 251 of the connecting member 25. Correspondingly, the length L of the weak section 251 is 1 is the length of the weak section 251 in the spiral direction of the spring, that is, the length dimension of the area where the wire diameter of the spring is reduced is L 1 Of course, if the connecting member 25 is a V-shaped spring sheet or a C-shaped spring sheet, the length L of the weak section 251 is 1 It is the dimension of the weak section 251 in the extension direction of the length of the elastic piece.

[0216] For example, the length L of the weak section 251 is 1 It can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, etc.

[0217] 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 enough 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, and 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 be 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.

[0218] In some embodiments, see Figure 7 and Figure 8 As shown, the connector 25 may further include a first insulating member 252, and the first insulating member 252 is coated on the outside of the weak section 251. In other words, the first insulating member 252 is coated on the outside of the region of the connector 25 forming the weak structure.

[0219] Among them, the first insulating member 252 is coated on the outside of the weak section 251, so that the first insulating member 252 plays a role in protecting or insulating and isolating 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 an insulating rubber layer coated on the outside of the weak section 251 of the connecting member 25.

[0220] For example, in Figure 8 In the embodiment, the first insulating member 252 is an insulating rubber layer covering the outer side of the weak section 251 , wherein the first insulating member 252 may be made of various materials, such as rubber, silicone or plastic.

[0221] In this embodiment, by wrapping the first insulating member 252 on the outer side of the weak section 251 of the connector 25, on the one hand, the first insulating member 252 can play a certain protective role on the weak section 251, so as to reduce the risk of the weak section 251 being accidentally broken due to wear or bump, 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 is melted when a short circuit occurs in the battery cell 20, so as to reduce the phenomenon that the weak section 251 overlaps with the wall 211 or the first current collecting member 24 under the elastic force of the connector 25 after it is melted, thereby reducing the risk of the weak section 251 of the connector 25 overlapping with other components after it is melted.

[0222] According to some embodiments of the present application, see Figure 6 and Figure 7 As shown, the connecting member 25 may further include a first connecting section 253, and 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 portion, the first connecting section 253 is connected to one end of the weak section 251 close to the wall portion 211, and the first connecting section 253 abuts against the wall portion 211.

[0223] The minimum flow area of ​​the first connection section 253 is greater than the minimum flow area of ​​the weak section 251, that is, in the extension direction of the connection member 25, the cross-sectional area of ​​the first connection section 253 is greater than the cross-sectional area of ​​the weak section 251. Exemplarily, in an embodiment where the connection member 25 is a spring, the minimum flow area of ​​the first connection section 253 is greater than the minimum flow area of ​​the weak section 251, which means that the wire diameter of the first connection section 253 is greater than the wire diameter of the weak section 251.

[0224] 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 and the wall portion 211 abut against each other, 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 and the wall portion 211 abut against each other, which is beneficial to improving the flow area between the connector 25 and the wall portion 211.

[0225] According to some embodiments of this application, please continue to refer to Figure 6 and Figure 7As shown, the connector 25 may further include a second connecting section 254, the minimum flow area of ​​which is greater than the minimum flow area of ​​the weak section 251. Along the thickness direction X of the wall portion, the second connecting section 254 is connected to one end of the weak section 251 close to the first current collecting member 24, and the second connecting section 254 abuts against the first current collecting member 24.

[0226] Among them, the minimum flow area of ​​the second connecting section 254 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 second connecting section 254 is greater than the cross-sectional area of ​​the weak section 251. Exemplarily, in an embodiment where the connecting member 25 is a spring, the minimum flow area of ​​the second connecting section 254 is greater than the minimum flow area of ​​the weak section 251, which means that the wire diameter of the second connecting section 254 is greater than the wire diameter of the weak section 251. Optionally, the wire diameter of the first connecting section 253 of the connecting member 25 is equal to the wire diameter of the second connecting section 254 of the connecting member 25, so as to facilitate processing, and the weak section 251 of the spring can be formed by only reducing the wire diameter of the middle area of ​​the spring, and the first connecting section 253 and the second connecting section 254 are respectively formed on both sides of the weak section 251 along the thickness direction X of the wall.

[0227] 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 beneficial to improving the flow area between the connector 25 and the first current collecting component 24.

[0228] According to some embodiments of the present application, see Figure 6 and Figure 7 As shown, the connecting member 25 is a spring, and along the thickness direction X of the wall portion, two ends of the spring abut against the first current collecting member 24 and the wall portion 211 respectively.

[0229] The structure of the connecting member 25 as a spring can be various, for example, the connecting member 25 can be a conical spring or a cylindrical spring. Figure 7 In the embodiment, the connecting member 25 is a conical spring, and the outer diameter of one end of the connecting member 25 abutting against the wall 211 in the thickness direction X of the wall is larger than the outer diameter of one end of the connecting member 25 abutting against the first current collecting member 24 in the thickness direction X of the wall. Fig. 9 As shown, Fig. 9This is a partial cross-sectional view of the connector 25 of the battery cell 20 provided in some embodiments of the present application in other embodiments. The connector 25 may also be a cylindrical spring.

[0230] In this embodiment, by setting the connecting piece 25 as a spring abutting between the first current collecting component 24 and the wall portion 211, the connecting piece 25 with such a structure is easy to assemble, which is beneficial to reduce the difficulty of assembling the connecting piece 25 between the wall portion 211 and the first current collecting component 24, and is beneficial to improve the structural stability of the connecting piece 25 abutting between the wall portion 211 and the first current collecting component 24, so as to improve the assembly stability of the connecting piece 25.

[0231] According to some embodiments of the present application, referring to Figure 6 and Figure 7 , and please refer to Fig.10 and Fig.11 , Fig.10 Schematic diagram of the assembly of the wall portion 211 of the battery cell 20 and the connector 25 provided in some embodiments of the present application, Fig.11 A partial cross-sectional view of a wall portion 211 of a battery cell 20 provided in some embodiments of the present application. Along the thickness direction X of the wall portion, a receiving portion 2111 is provided on one side of the wall portion 211 facing the electrode assembly 23 , and a portion of the connector 25 is inserted into the receiving portion 2111 .

[0232] Among them, the accommodating portion 2111 is an accommodating space arranged on the surface of the wall 211 facing the electrode assembly 23 in the thickness direction X of the wall, 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 can be inserted into the accommodating portion 2111.

[0233] For example, in Fig.11 In the embodiment, the accommodation portion 2111 is a blind hole provided on the surface of the wall portion 211 facing the electrode assembly 23, and the end of the connector 25 away from the first current collecting member 24 in the thickness direction X of the wall portion is inserted into the blind hole and abuts against the bottom surface of the blind hole. Of course, in other embodiments, the accommodation portion 2111 may also be a groove or a stepped hole provided on the wall portion 211.

[0234] In the present 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 one 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 reduce the difficulty of assembling the connector 25 between the wall portion 211 and the first current collecting member 24, so as to improve the production efficiency of the battery cell 20, and is beneficial to improve 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 improve the structural stability of the connector 25 assembled between the wall portion 211 and the first current collecting member 24, so as to reduce the shaking of the connector 25 during use.

[0235] According to some embodiments of the present application, see Fig.10 and Fig.11 As shown, the side surface of the accommodating portion 2111 includes a limiting surface 2111 a, and the limiting surface 2111 a is configured to limit the connection member 25 from being separated from the accommodating portion 2111 along the thickness direction X of the wall.

[0236] 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 in 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 the limiting surface 2111a.

[0237] For example, in an embodiment where the accommodation portion 2111 is a blind hole, a hole wall of the blind hole forms a limiting surface 2111 a for limiting the connection member 25 from being separated from the accommodation portion 2111 .

[0238] In this embodiment, a limited surface 2111a is formed on the side of the accommodating portion 2111, and the limited 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, and reducing the risk of connection failure between the wall portion 211 and the first current collecting component 24.

[0239] In some embodiments, see Figure 7, Fig.10 and Fig.11 As shown, the connecting member 25 is a conical spring, and the limiting surface 2111a is a conical surface that fits the outer circumferential surface of the conical spring. 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.

[0240] Among them, the limiting surface 2111a is a conical surface that matches the outer circumferential 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.

[0241] The large end of the limiting surface 2111a is further away from the first current collecting member 24 than the small end of the limiting surface 2111a, that is, in the thickness direction X of the wall portion, the aperture of the end of the side surface of the accommodating portion 2111 that penetrates the surface of the wall portion 211 facing the electrode assembly 23 is smaller than the aperture of the end of the side surface of the accommodating portion 2111 close to the bottom, and correspondingly, the outer diameter of the end of the connecting piece 25 of the conical spring close to the first current collecting member 24 in the thickness direction X of the wall portion is smaller than the outer diameter of the end of the connecting piece 25 of the conical spring far from the first current collecting member 24 in the thickness direction X of the wall portion. It should be noted that the large end of the limiting surface 2111a is the end of the limiting surface 2111a of the conical structure with the largest aperture, and correspondingly, the small end of the limiting surface 2111a is the end of the limiting surface 2111a of the conical structure with the smallest aperture.

[0242] 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.

[0243] In some embodiments, see Fig.10 and Fig.11 As shown, the diameter of the large end of the limiting surface 2111a in the thickness direction X of the wall is D 1 The diameter of the small end of the limiting surface 2111a in the thickness direction X of the wall is D 2 , meet, 0.5mm≤D 1 -D 2 ≤5mm.

[0244] Among them, Fig.11The diameter of the large end of the limiting surface 2111a in the thickness direction X of the wall is D 1 , that is, the diameter of the end of the limiting surface 2111a away from the first current collecting member 24 in the thickness direction X of the wall is D 1 The diameter of the small end of the limiting surface 2111a in the thickness direction X of the wall is D 2 The diameter of the limiting surface 2111a at one end close to the first current collecting member 24 in the thickness direction X of the wall is D 2 .

[0245] 0.5mm≤D 1 -D 2 ≤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 diameter D of the large end of the limiting surface 2111a is 1 The diameter D of the small end of the limiting surface 2111a 2 The difference 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.

[0246] 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, so that the phenomenon of the connecting member 25 being separated from the accommodating portion 2111 along the thickness direction X of the wall portion can be further reduced, so as to further reduce 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 5mm to alleviate the difficulty of assembling the connecting piece 25 into the accommodating portion 2111, which is beneficial to reducing the difficulty of assembling the connecting piece 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 0.5mm to 5mm, which can not only achieve a better limiting effect of the limiting surface 2111a on the connecting piece 25, but also reduce the difficulty of inserting the connecting piece 25 into the accommodating portion 2111.

[0247] According to some embodiments of the present application, see Figure 6 and Figure 7 As shown, along the thickness direction X of the wall portion, the compression ratio of the connecting member 25 is 10%-50%.

[0248] The compression ratio of the connector 25 is 10%-50%, that is, in the thickness direction X of the wall, the difference between the length of the connector 25 in the 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 211 and the first current collecting member 24 (the length of the connector 25 compressed between the wall 211 and the first current collecting member 24 under force) divided by the length of the connector 25 in the 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 211 and the first current collecting member 24, the length compressed in the thickness direction X of the wall is 10% to 50% of the original length of the connector 25 in the thickness direction X of the wall.

[0249] In this embodiment, the compression ratio of the spring serving as the connector 25 before assembly and after being assembled between the wall portion 211 and the first current collecting member 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 against the wall portion 211 and the first current collecting member 24, and is beneficial to enhancing the structural stability of the connector 25 assembled between the wall portion 211 and the first current collecting member 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 of the connector 25 due to excessive compression, thereby facilitating improving the service life of the connector 25. Therefore, the compression ratio of the connector 25 is set to 10% to 50%, which can not only take into account the better abutment effect of the connector 25 with the wall portion 211 and the first current collecting member 24, but also alleviate the phenomenon that the connector 25 cannot recover its elastic deformation due to excessive compression.

[0250] According to some embodiments of the present application, referring to Fig.12 , Fig.13 , Fig.14 and Fig.15 , Fig.12 The structural exploded diagram of the battery cell 20 provided in some embodiments of the present application is as follows: Fig.13 A cross-sectional view of a battery cell 20 provided in some other embodiments of the present application, Fig.14 for Fig.12 The partial enlarged view of the battery cell 20 at C is shown. Fig.15 The following is a schematic diagram of the connection between the connector 25 of the battery cell 20 and the first current collecting member 24 provided in some other embodiments of the present application. The connector 25 and the first current collecting member 24 are integrally formed.

[0251] 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.

[0252] In this embodiment, by setting the connecting member 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 connecting member 25 and the first current collecting member 24, so as to reduce the risk of connection failure between the connecting member 25 and the first current collecting member 24, and the connecting member 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, so as to improve the production efficiency of the battery cell 20.

[0253] In some embodiments, reference Fig.13 , Fig.14 and Fig.15 , and please refer to Fig.16 , Fig.16 A cross-sectional view of a battery cell 20 provided in some embodiments of the present application in which a connector 25 is 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, the first direction Y being perpendicular to the thickness direction X of the wall portion. Along the first direction Y, a portion of the connector 25 forms a weak section 251, the weak section 251 is connected to the first current collecting member 24, and the minimum flow area of ​​the weak section 251 is the minimum flow area S of the connector 25. 1 .

[0254] Part of the connector 25 forms a weak section 251, that is, in the first direction Y, the connector 25 forms a weak section, which is the weak section 251, so that the wall portion 211 and the first current collecting member 24 are electrically connected to each other through the weak section 251 of the connector 25, that is, the current flow between the wall portion 211 and the first current collecting member 24 will pass through the weak section 251 of the connector 25, so that the cross-sectional area of ​​the weak section 251 perpendicular to the first direction Y is the minimum flow area S of the connector 25. 1 That is to say, the weak section 251 of the connecting member 25 is the minimum flow area of ​​the connecting member 25 , and the area of ​​the cross section of the weak section 251 perpendicular to the first direction Y is the minimum flow area of ​​the connecting member 25 .

[0255] The weak section 251 is connected to the first current collecting component 24, that is, the connecting member 25 is a structure interconnected with the first current collecting component 24 through the weak section 251, that is, the part where the connecting member 25 and the first current collecting component 24 are interconnected 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.

[0256] In the present embodiment, the first current collecting member 24 and the connector 25 are arranged in 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, 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, the structure in which the weak section 251 of the connector 25 is connected to the first current collecting member 24 can realize that the minimum flow area of ​​the connector 25 is smaller than the minimum flow area of ​​the first pole ear 232, and the first current collecting member 24 and the connector 25 are easy to manufacture, the structure is simple, and the manufacturing is convenient. On the other hand, the fuse position of the connector 25 can be controlled, and the fuse position can be controlled at the portion 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.

[0257] According to some embodiments of the present application, see Fig.15 and Fig.16 As shown, along the first direction Y, the length of the weak section 251 is L 2 , meet, 0.3mm≤L 2 ≤5mm.

[0258] Among them, the length of the weak section 251 is L 2 is the dimension of the weak section 251 in the first direction Y, and is also the length L of the weak section 251 on the path of the connecting member 25 for current flow. 2 .

[0259] For example, the length L of the weak section 251 is 2 It can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, etc.

[0260] In this embodiment, by setting the length of the weak section 251 in the first direction Y to 0.3 mm to 5 mm, that is, the length of the weak section 251 in the extension direction of the connector 25 is 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 enough space to be melted when a short circuit occurs in the battery cell 20, thereby effectively reducing the phenomenon of incorrect overlap of the weak section 251 of the connector 25 after melting, thereby reducing the overlap 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, so as to alleviate the phenomenon that the weak section 251 occupies too much space in the first direction Y, thereby improving the internal space utilization rate of the battery cell 20. Therefore, by setting the length of the weak section 251 in the first direction Y to 0.3 mm to 5 mm, while taking into account the reduction of the risk of incorrect overlap of the weak section 251 of the connector 25 after melting, the space occupied by the weak section 251 of the connector 25 in the first direction Y can also be effectively saved.

[0261] According to some embodiments of the present application, see Fig.14 , Fig.15 and Fig.16 As shown, the connecting member 25 may also 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 component 24, and the first current collecting component 24, the weak section 251 and the first connecting section 253 are arranged along the first direction Y.

[0262] 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 .

[0263] 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 to say, 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.

[0264] 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 .

[0265] 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 at 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 improve the flow area between the connector 25 and the wall portion 211.

[0266] According to some embodiments of the present application, see Fig.14 , Fig.15 and Fig.16 As shown, the first connection section 253 includes a first connection portion 2531, a bent portion 2532, and a second connection portion 2533 connected in sequence, the first connection portion 2531 is connected to the weak section 251, and the second connection portion 2533 is connected to the wall portion 211. Along the thickness direction X of the wall portion, the second connection portion 2533 is closer to the wall portion 211 than the first connection portion 2531, and the second connection portion 2533 abuts against the wall portion 211.

[0267] 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 sequentially connected structures, and the second connecting part 2533 and the wall part 211 are interconnected.

[0268] 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 connecting the first connection part 2531, the bending part 2532 and the second connection part 2533 to each other has a "Z" shape structure.

[0269] In this embodiment, the first connecting section 253 is provided with a first connecting portion 2531, a bending 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 that the wall portion 211 is electrically connected to the first current collecting member 24 through the connecting piece 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 with this structure can compensate for the gap between the first current collecting member 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 member 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.

[0270] In some embodiments, see Fig.14 and Fig.16 As shown, 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 , and the second surface 242 is flush with the first surface 2531 a .

[0271] 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 where the first protrusion 241 is provided on the first current collecting component 24, the first protrusion 241 is protruding on the second surface 242 of the first current collecting component 24.

[0272] In the present embodiment, by setting the first surface 2531a of the first connection 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 connection 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 outer shell 21, and the first current collecting member 24 and the first connection 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 rate of the battery cell 20. On the other hand, it is convenient to integrally form the first current collecting member 24 and the first connection portion 2531 through the same plate material, and it is convenient to form a weak section 251 between the first current collecting member 24 and the first connection portion 2531, which is conducive to reducing the manufacturing difficulty of the integrally formed first current collecting member 24 and the first connection portion 2531.

[0273] In some embodiments, see Fig.14 and Fig.16 As shown, along the thickness direction X of the wall, the first connection portion 2531 has a third surface 2531 b away from the wall 211 , and the first current collecting member 24 has a fourth surface 243 away from the wall 211 , and the fourth surface 243 is flush with the third surface 2531 b .

[0274] 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 away from the wall portion 211 and the fourth surface 243 of the first current collecting member 24 away from the wall portion 211 are coplanar structures.

[0275] In the present embodiment, by setting the third surface 2531b of the first connecting portion 2531 away from the wall portion 211 and the fourth surface 243 of the first current collecting member 24 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 outer 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 rate 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 through 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 manufacturing difficulty of the integrally formed first current collecting member 24 and the first connecting portion 2531.

[0276] According to some embodiments of the present application, see Fig.14 , Fig.15 and Fig.16 As shown, the second connection portion 2533 is connected to the wall portion 211 by welding.

[0277] The connecting member 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 welding mark 30 is formed between the second connecting portion 2533 and the wall portion 211 to achieve electrical connection between the connecting member 25 and the wall portion 211. Of course, in other embodiments, the second connecting portion 2533 may also be a structure that abuts or clamps against the wall portion 211.

[0278] For example, laser welding or ultrasonic welding may be used between the second connection portion 2533 and the wall portion 211 .

[0279] 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.

[0280] In some embodiments, the welding area between the second connection portion 2533 and the wall portion 211 is S 2 , meet, 30mm 2 ≤S 2 ≤100mm 2 .

[0281] The welding area S between the second connection portion 2533 and the wall portion 211 is 2 The cross-sectional area of ​​the weld mark 30 formed by welding the second connection portion 2533 and the wall portion 211 at the interface between the second connection portion 2533 and the wall portion 211 is S 2 .

[0282] In this embodiment, the welding area between the second connecting portion 2533 of the first connecting section 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 connection part 2533 and the wall part 211 is set to be greater than or equal to 30 mm 2 , in order to improve the welding effect between the second connection part 2533 and the wall part 211, so as to improve the connection reliability and connection stability between the connection member 25 and the wall part 211, on the other hand, the welding area of ​​the second connection part 2533 and the wall part 211 is set to be less than or equal to 100mm 2, so as to reduce the welding difficulty between the second connection part 2533 and the wall part 211, and reduce the welding power required for welding the second connection part 2533 and the wall part 211 to each other, so as to effectively reduce the assembly difficulty between the connection member 25 and the wall part 211, which is beneficial to improve the production efficiency of the battery cell 20 and reduce the production cost of the battery cell 20. Therefore, the welding area between the second connection part 2533 and the wall part 211 is set to 30mm 2 Up to 100mm 2 , while taking into account the welding quality between the connecting piece 25 and the wall portion 211 , it can also effectively reduce the difficulty of welding and assembly between the connecting piece 25 and the wall portion 211 .

[0283] According to some embodiments of the present application, see Fig.15 and Fig.16 As shown, along the first direction Y, a groove 255 is formed between the first current collecting member 24 and the first connecting section 253 , and the bottom wall of the groove 255 is a weak section 251 .

[0284] 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 connecting piece 25 and the first current collecting component 24, a groove 255 is formed between the first connecting section 253 of the connecting piece 25 and the first current collecting component 24, so that the portion of the connecting piece 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.

[0285] 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.

[0286] 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 is 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.

[0287] In some embodiments, see Fig.15 and Fig.16 As shown, along the second direction Z, a groove 255 is formed on at least one side of the weak section 251 , and the first direction Y, the second direction Z and the thickness direction X of the wall portion are perpendicular to each other.

[0288] 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 .

[0289] For example, in Fig.15 In the figure, 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 connecting member 25 in the thickness direction X of the wall portion, so that the portion of the connecting member 25 located between the bottom surfaces of the two grooves 255 is the weak section 251 of the connecting member 25.

[0290] 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 it is easy to process.

[0291] Of course, the structure of the connecting member 25 is not limited thereto. In some embodiments, the dining table Fig.17 and Fig.18 , Fig.17 Schematic diagram of connection between the connector 25 of the battery cell 20 and the first current collecting member 24 in other embodiments provided in some other embodiments of the present application, Fig.18 A cross-sectional view of a battery cell 20 provided in some other embodiments of the present application and connected to a first current collecting member 24 in other embodiments. A groove 255 is formed on at least one side of the weak section 251 along the thickness direction X of the wall.

[0292] 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 may be formed on only one side of the weak section 251, or the groove 255 may be formed on both sides of the weak section 251.

[0293] For example, in Fig.17 and Fig.18 In the embodiment, the weak section 251 is formed with a groove 255 on only one side in the thickness direction X of the wall, the groove 255 penetrates both ends of the connector 25 in the second direction Z, and the groove 255 is located on the side of the weak section 251 facing the wall 211 in the thickness direction X of the wall, so that the portion of the connector 25 corresponding to the groove bottom surface of the groove 255 is the weak section 251 of the connector 25. Of course, in other embodiments, the groove 255 can also be provided on the side of the weak section 251 away from the wall 211 in the thickness direction X of the wall.

[0294] In this embodiment, a groove 255 is formed on at least one side of the weak section 251 along the thickness direction X of the wall portion, so that the groove 255 is located on one side of the weak section 251 along the thickness direction X of the wall portion, so that the weak section 251 is formed on the bottom wall of the groove 255, which has a simple structure and is easy to process.

[0295] According to some embodiments of the present application, see Figure 4 , Figure 5 and Figure 6 As shown, the first electrode tab 232 is the positive electrode tab of the electrode assembly 23. That is, the first electrode tab 232 is a component formed by stacking and connecting the regions on the positive electrode sheet 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.

[0296] 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 connecting member 25 is used to output the positive electrode of the electrode assembly 23, so that the wall portion 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 reducing the risk of leakage of the battery cell 20 during use.

[0297] According to some embodiments of the present application, see Figure 3 , Figure 4 and Figure 5 As shown, the first electrode terminal 22 is insulated and installed on the wall 211 , along the thickness direction X of the wall, the first current collecting member 24 is arranged between the main body 231 and the wall 211 , and the first electrode tab 232 is arranged at one end of the main body 231 facing the wall 211 .

[0298] In the present embodiment, the first electrode terminal 22 is insulated and installed on the wall portion 211, and the first pole tab 232 is arranged 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 pole 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 pole tab 232 and the first current collecting member 24 can be reduced, and the difficulty of assembling the first current collecting member 24 and the first electrode terminal 22 can be reduced, which is beneficial to improving the production efficiency of the battery cell 20. On the other hand, there is no need to excessively extend the first pole tab 232 or the first current collecting member 24, thereby reducing the risk of overlapping between the first pole tab 232 or the first current collecting member 24 and other components.

[0299] According to some embodiments of this application, please continue to refer to Figure 3 , Figure 4 and Figure 5 As shown, the battery cell 20 may further include a second electrode terminal 26 and a second current collecting member 27, wherein the second electrode terminal 26 is insulated and mounted on the housing 21, and the second current collecting member 27 is disposed in the housing 21. The electrode assembly 23 further includes a second electrode tab 233, which is disposed on the main body 231, and has a polarity opposite to that of the first electrode tab 232, and is electrically connected to the second electrode terminal 26 through the second current collecting member 27.

[0300] Exemplarily, the second electrode terminal 26 is insulated and installed on the wall portion 211, and correspondingly, the second pole ear 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 pole ear 233 is connected to the second electrode terminal 26 through the second current collecting member 27.

[0301] In the present 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 electrodes of the battery cell 20, wherein, by insulating and installing the second electrode terminal 26 on the outer shell 21, it is helpful to reduce the risk of short circuit between the second electrode terminal 26 and the connecting member 25.

[0302] According to some embodiments of the present application, see Figure 3 and Figure 4 As shown, the housing 21 may include a shell 212 and an end cover 213 . The shell 212 has an interior forming a receiving cavity with an opening 2121 . The receiving cavity is used to receive the electrode assembly 23 . The end cover 213 closes the opening 2121 . The end cover 213 is a wall portion 211 .

[0303] 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, the first electrode terminal 22 and the second electrode terminal 26 are both insulated and mounted on the end cap 213 of the housing 21.

[0304] 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 is convenient for connecting the connecting part 25 to the wall portion 211 of the outer shell 21, which is beneficial to reduce the difficulty of assembling the battery cell 20 and improve the production efficiency of the battery cell 20.

[0305] It should be noted that the structure of the battery cell 20 is not limited thereto. In some embodiments, the battery cell 20 may also be other structures. For example, the housing 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 is enclosed to form an opening 2121. The side wall and the wall portion 211 jointly define a housing cavity for accommodating the electrode assembly 23, and 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 to the end cap 213 in the thickness direction X of the wall portion.

[0306] In the present embodiment, by setting the wall portion 211 of the outer shell 21 as a wall of the shell 212 that is arranged opposite to the end cover 213 in the thickness direction X of the wall portion, the battery cell 20 adopting such a structure can make the wall portion 211 used for connecting with the connecting piece 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 connecting piece 25, which is beneficial to improving the service life of the connecting piece 25, and can alleviate the phenomenon that the force generated when other components pull or twist the wall portion 211 acts on the end cover 213, so as to reduce the risk of connection failure between the end cover 213 and the shell 212, which is beneficial to further reduce the risk of leakage of the battery cell 20 during use.

[0307] According to some embodiments of the present application, the present application further provides a battery 100 , and the battery 100 includes a battery cell 20 of any of the above solutions.

[0308] Among them, see Figure 2 As shown, the battery 100 may further include a housing 10 , in which the battery cells 20 are accommodated.

[0309] 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 .

[0310] Optionally, the second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure. The first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 jointly define an assembly space; the first box body 11 and the second box body 12 can also be hollow structures both with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0311] 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 cuboid. Figure 2 In the embodiment, the box body 10 is a rectangular parallelepiped structure.

[0312] Optionally, the number of battery cells 20 disposed in the box body 10 may be one or more. Figure 2 In the embodiment, a plurality of battery cells 20 are arranged in the box 10 of the battery 100, and the plurality of battery cells 20 can be connected in series, in parallel or in a mixed connection. The mixed connection means that the plurality of battery cells 20 are both connected in series and in parallel. The plurality of battery cells 20 can be directly connected in series, in parallel or in a mixed connection, and then the whole formed by the plurality of battery cells 20 is accommodated in the box 10; of course, the battery 100 can also be a battery module formed by first connecting the plurality of battery cells 20 in series, in parallel or in a mixed connection, and then the plurality of battery modules are connected in series, in parallel or in a mixed connection to form a whole, and then accommodated in the box 10.

[0313] The battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which connects the plurality of battery cells 20 to achieve electrical connection between the plurality of battery cells 20 .

[0314] It should be noted that, in some embodiments, the battery 100 may not be provided with a box 10, and the battery 100 includes a plurality of battery cells 20, and the battery 100 composed of a plurality of battery cells 20 may be directly assembled on an electrical device to provide electrical energy to the electrical device through the plurality of battery cells 20. In other words, the box 10 may be used as a part of the electrical device. Taking the vehicle 1000 as an example of the electrical device, the box 10 may be used as a part of the chassis structure of the vehicle 1000, for example, a part of the box 10 may become at least a part of the floor of the vehicle 1000, or a part of the box 10 may become at least a part of the crossbeam and longitudinal beam of the vehicle 1000.

[0315] In some embodiments, see Figure 2 As shown, the battery 100 may further include a battery management system (not shown in the figure). The battery management system is electrically connected to the wall portion 211, and the battery management system is configured to give an early warning when the connector 25 is fused.

[0316] The battery management system is used to manage and monitor the use status of the battery 100. The specific structure of the battery management system can be found in the relevant technology and will not be described in detail here.

[0317] 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 message.

[0318] In an embodiment, the battery 100 is also provided with a battery management system, which is electrically connected to the wall 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 fuse, so as to provide an early warning reminder to the operator or user, thereby reducing further damage or impact caused by the short circuit of the battery cell 20 to the operator or user, which is beneficial to improving the reliability of the battery 100.

[0319] According to some embodiments of the present application, the present application further provides an electrical device, which includes a battery cell 20 according to any of the above schemes, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0320] The electrical device may be any of the aforementioned devices or systems using the battery cell 20 .

[0321] According to some embodiments of the present application, see Figures 3 to 8 as well as Figure 10 to Figure 11As shown, the present application provides a battery cell 20, which includes a shell 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 shell 21 has a wall portion 211, and the shell 21 includes a shell 212 and an end cover 213. The shell 212 forms a receiving cavity with an opening 2121 inside, and the end cover 213 closes the opening 2121. The end cover 213 is the wall portion 211. The first electrode terminal 22 and the second electrode terminal 26 are both insulated and installed on the wall portion 211. The electrode assembly 23 is accommodated in the receiving cavity, and the electrode assembly 23 includes a main body 231, a first pole ear 232 and a second pole ear 233. The first pole ear 232 and the second pole ear 233 are both connected to one end of the main body 231 facing the wall portion 211 in the thickness direction X of the wall portion. The first pole ear 232 is the positive pole ear of the electrode assembly 23, and the second pole ear 233 is the negative pole ear of the electrode assembly 23. Along the thickness direction X of the wall portion, the first current collecting member 24 and the second current collecting member 27 are both disposed between the wall portion 211 and the main body portion 231. The first current collecting member 24 connects the first electrode tab 232 and the first electrode terminal 22, and the second current collecting member 27 connects the second electrode tab 233 and the second electrode terminal 26, so as to electrically connect the first electrode terminal 22 and the electrode assembly 23, and the second electrode terminal 26 and the electrode assembly 23. The connector 25 is accommodated in the housing 21, and the connector 25 is disposed separately from the first current collecting member 24, and the connector 25 electrically connects the wall portion 211 and the first current collecting member 24, and 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 S. 1 , meet, 2mm 2 ≤S 1 ≤20mm 2 .

[0322] 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 connector section 253, a weak section 251, and a second connector section 254. The first connector section 253 and the second connector section 254 are respectively connected to both ends of the weak section 251 in the thickness direction X of the wall portion. The first connector section 253 abuts against the wall portion 211, and the second connector section 254 abuts against the first current collecting member 24. The cross-sectional area of ​​the first connector section 253 perpendicular to the spiral direction of the conical spring and the cross-sectional area of ​​the second connector section 254 perpendicular to the spiral direction of the conical spring are both greater than the cross-sectional area of ​​the weak section 251 perpendicular to the spiral direction of the conical spring, and the cross-sectional area of ​​the weak section 251 perpendicular to the spiral direction of the conical spring is the minimum flow area S of the connector 25. 1Along the spiral direction of the conical spring, the length of the weak section 251 is L 1 , meet, 0.3mm≤L 1 ≤5mm. The connector 25 also includes a first insulating member 252, which is coated on the outside of the weak section 251. Along the thickness direction X of the wall portion, a receiving portion 2111 is provided on the side of the wall portion 211 facing the electrode assembly 23. The first connecting section 253 of the connector 25 is inserted into the receiving portion 2111 and abuts against the bottom of the receiving portion 2111. The side of the receiving portion 2111 includes a limiting surface 2111a, which is configured to limit the connector 25 from escaping from the receiving portion 2111 along the thickness direction X of the wall portion. The limiting surface 2111a is a conical surface that fits the outer peripheral 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, and the diameter of the large end of the limiting surface 2111a in the thickness direction X of the wall portion is D 1 The diameter of the small end of the limiting surface 2111a in the thickness direction X of the wall is D 2 , meet, 0.5mm≤D 1 -D 2 ≤5mm.

[0323] According to some embodiments of the present application, see Figures 12 to 16As shown, the present application provides a battery cell 20, which includes a shell 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 shell 21 has a wall portion 211, and the shell 21 includes a shell 212 and an end cover 213. The shell 212 forms a receiving cavity with an opening 2121 inside, and the end cover 213 closes the opening 2121. The end cover 213 is the wall portion 211. The first electrode terminal 22 and the second electrode terminal 26 are both insulated and installed on the wall portion 211. The electrode assembly 23 is accommodated in the receiving cavity, and the electrode assembly 23 includes a main body 231, a first pole ear 232 and a second pole ear 233. The first pole ear 232 and the second pole ear 233 are both connected to one end of the main body 231 facing the wall portion 211 in the thickness direction X of the wall portion. The first pole ear 232 is the positive pole ear of the electrode assembly 23, and the second pole ear 233 is the negative pole ear of the electrode assembly 23. Along the thickness direction X of the wall portion, the first current collecting member 24 and the second current collecting member 27 are both disposed between the wall portion 211 and the main body portion 231. The first current collecting member 24 connects the first electrode tab 232 and the first electrode terminal 22, and the second current collecting member 27 connects the second electrode tab 233 and the second electrode terminal 26, so as to electrically connect the first electrode terminal 22 and the electrode assembly 23, and the second electrode terminal 26 and 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 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, and the minimum flow area of ​​the connector 25 is S 1 , meet, 2mm 2 ≤S 1 ≤20mm 2 .

[0324] The first current collecting member 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 member 24 and the first connecting section 253, and the cross-sectional area of ​​the weak section 251 perpendicular to the first direction Y is the minimum flow area S of the connecting member 25. 1 , and the length of the weak section 251 is L 2 , meet, 0.3mm≤L 2 ≤5mm. The first connecting section 253 includes a first connecting portion 2531, a bending 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 , meet, 30mm 2 ≤S 2 ≤100mm 2 . Along the thickness direction X of the wall, the first connection 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, the second surface 242 is flush with the first surface 2531a, the first connection portion 2531 has a third surface 2531b away from the wall 211, the first current 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. Along the first direction Y, a groove 255 is formed between the first current collecting member 24 and the first connection section 253, and the bottom wall of the groove 255 is 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 thickness direction X of the wall are perpendicular to each other.

[0325] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0326] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: a housing having a wall portion; A first electrode terminal, insulated and mounted on the housing; An electrode assembly is contained in the housing, the electrode assembly comprising a main body and a first electrode tab, wherein the first electrode 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, characterized in that: The minimum flow area of ​​the connector is S1, which satisfies 2mm 2 ≤S1≤20mm 2 .

3. The battery cell according to claim 1 or 2, characterized in that: The connecting piece and the first current collecting member are arranged separately.

4. The battery cell according to claim 3, characterized in that: 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 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, characterized in that: 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.

6. The battery cell according to claim 5, characterized in that: Along the extension direction of the connecting piece, the length of the weak section is L1, which satisfies 0.3mm≤L1≤5mm.

7. The battery cell according to claim 5, characterized in that: The connecting piece also includes: The first insulating member is coated on the outer side of the weak section.

8. The battery cell according to claim 5, characterized in that: The connecting member further comprises a first connecting section, wherein 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 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 claim 5, characterized in that: 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 component, and the second connecting section abuts against the first current collecting component.

10. The battery cell according to claim 4, characterized in that: 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, characterized in that: Along the thickness direction of the wall portion, a receiving portion is provided on one side of the wall portion facing the electrode assembly, and a portion of the connecting member is inserted into the receiving portion.

12. The battery cell according to claim 11, characterized in that: The side surface of the accommodation portion includes a limiting surface, and the limiting surface is configured to limit the connection member from being separated from the accommodation portion along the thickness direction of the wall portion.

13. The battery cell according to claim 12, characterized in that: The connecting piece is a conical spring, the limiting surface is a conical surface that matches the outer circumferential 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.

14. The battery cell according to claim 13, characterized in that: 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 claim 10, characterized in that: 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, characterized in that: The connecting piece is integrally formed with the first current collecting member.

17. The battery cell according to claim 16, characterized in that: Along the thickness direction of the wall portion, the first current collecting member is disposed between the main body portion and the wall portion; Among them, 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, and the weak section is connected to the first current collecting component. 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, characterized in that: Along the first direction, the length of the weak section is L2, satisfying 0.3 mm ≤ L2 ≤ 5 mm.

19. The battery cell according to claim 17, characterized in that: The connecting member also includes a first connecting section, a minimum flow area of ​​the first connecting section is greater than a 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 member, and the first current collecting member, the weak section and the first connecting section are arranged along the first direction.

20. The battery cell according to claim 19, characterized in that: The first connecting section comprises a first connecting portion, a bending portion, and a second connecting portion which are 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, characterized in that: The first connection portion has a first surface facing the wall portion along 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, characterized in that: 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 claim 20, characterized in that: The second connection portion is connected to the wall portion by welding.

24. The battery cell according to claim 23, characterized in that: The welding area between the second connection part and the wall part is S2, which satisfies 30mm 2 ≤S2≤100mm 2 .

25. The battery cell according to claim 19, characterized in that: 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 is the weak section.

26. The battery cell according to claim 25, characterized in that: 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, characterized in that: 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 claim 1, characterized in that: The first electrode tab is a positive electrode tab of the electrode assembly.

29. The battery cell according to claim 1, characterized in that: 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 disposed between the main body portion and the wall portion, and the first electrode tab is disposed at one end of the main body portion facing the wall portion.

30. The battery cell according to claim 1, characterized in that 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 housing, and the second current collecting member is disposed in the housing; The electrode assembly further includes a second electrode tab, which is disposed on the main body, 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 claim 1, characterized in that The housing comprises: A shell body, wherein a receiving cavity with an opening is formed inside, and the receiving cavity is used to receive the electrode assembly; an end cap for closing the opening; Wherein, the end cover is the wall portion.

32. The battery cell according to claim 1, characterized in that The housing comprises: A shell, comprising an integrally formed side wall and the wall portion, wherein the side wall is disposed 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 housing cavity for housing the electrode assembly; An end cap closes the opening.

33. A battery, characterized in that: Comprising the battery cell according to any one of claims 1-32.

34. The battery according to claim 33, characterized in that The battery also includes: 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 connecting piece is fused.

35. An electrical device, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 32, wherein the battery cell is used to provide electrical energy.

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