Battery cell, battery, power utilization device and assembly method of battery cell

Abstract

A battery monomer, a battery, a power utilization device and an assembly method of the battery monomer, the battery monomer comprises: a housing assembly, which comprises a housing and a first pole, the housing comprises a housing body and a housing cover, the housing body has an opening, the housing cover covers the opening, and the housing body is provided with the first pole; and the battery core assembly comprises an active substance coating part and a conductive part, the active substance coating part is accommodated in the shell body, and the conductive part is electrically connected with the active substance coating part and the first pole. According to the invention, the probability of cracking at the weld joint of the shell body and the shell cover in the use process of the battery can be reduced, and the reliability of the single battery is improved.

Description

Battery cell, battery, electric device and battery cell assembly method Technical Field

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

[0002] In recent years, new energy vehicles have experienced rapid development. In the electric vehicle sector, batteries, as the power source, play an irreplaceable and important role. Improving the reliability of battery cells is an urgent issue.

[0003] Summary of the Invention

[0004] The embodiments of the present application provide a battery cell, a battery, an electrical device, and a method for assembling the battery cell, which is beneficial to improving the reliability of the battery cell.

[0005] In the first aspect, an embodiment of the present application provides a battery cell, comprising: a shell assembly, comprising a shell and a first pole, the shell comprising a shell body and a shell cover, the shell body having an opening, the shell cover covering the opening, and the shell body being provided with a first pole; a battery cell assembly, comprising an active material coating portion and a conductive portion, the active material coating portion being accommodated in the shell body, and the conductive portion electrically connecting the active material coating portion and the first pole.

[0006] In the above technical solution, in the battery, since the first poles of any adjacent battery cells are connected to each other, when the battery vibrates or deforms, the first poles between any adjacent battery cells will pull each other. At this time, since the first poles are arranged on the shell body, the force acting on the first poles will be preferentially transmitted to the shell body, and will not directly act on the shell cover. On the one hand, the distance for the force to be transmitted to the weld between the shell body and the shell cover can be extended. On the other hand, when subjected to force, the shell body will preferentially deform to reduce the force at the weld between the shell body and the shell cover, effectively reducing the probability of cracking at the weld between the shell body and the shell cover during battery use, and improving the reliability of the battery cell.

[0007] In some embodiments, the first pole is provided with a receiving portion, and at least a portion of the conductive portion is received in the receiving portion.

[0008] In the above technical solution, on the one hand, the first electrode is provided with a receiving portion, which can reduce the weight of the first electrode to a certain extent, thereby improving the weight energy density of the battery cell and the battery; on the other hand, by accommodating at least part of the conductive part in the receiving portion to occupy the space in the first electrode, the space occupied by the conductive part in the shell can be reduced. When the size of the shell is fixed, some space can be saved in the shell to accommodate a larger active material coating part, thereby improving the volume energy density of the battery cell; at the same time, accommodating at least part of the conductive part in the receiving portion can reduce the space occupied by the battery cell itself, so that a battery of the same volume can accommodate a larger number of battery cells, thereby also improving the volume energy density of the battery; in addition, accommodating at least part of the conductive part in the receiving portion can also reduce the redundancy of the conductive part in the shell to a certain extent, reduce the probability of short circuit between the conductive part and the active material coating part, reduce the probability of short circuit of the battery cell assembly, and thereby improve the working reliability and stability of the battery cell and the battery; accommodating at least part of the conductive part in the receiving portion of the first electrode facilitates the connection between the conductive part and the first electrode.

[0009] In some embodiments, the accommodating portion has a first accommodating groove, the surface of the first pole facing the active material coating portion is the inner end face of the pole, the notch of the first accommodating groove is formed on the inner end face of the pole, and at least part of the conductive portion is accommodated in the first accommodating groove.

[0010] In the above technical solution, on the one hand, the first receiving groove is provided on the first pole, which can reduce the weight of the first pole to a certain extent, so as to improve the weight energy density of the battery cell and the battery; on the other hand, since the notch of the first receiving groove is formed on the inner end face of the pole, and the inner end face of the pole is the surface of the first pole close to the active material coating part, the first receiving groove can be opened toward the active material coating part, thereby facilitating the conductive part to extend into the first receiving groove, thereby improving assembly efficiency; at the same time, since the first receiving groove is toward the active material coating part, the first receiving groove can also serve as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the shell. Since the electrolyte will be lost during the charge and discharge process of the battery cell, when the battery is charged and discharged, the electrolyte will be lost. When there is more electrolyte, the service life of the battery cell can be extended; and because the first receiving groove is facing the active material coating part, the first receiving groove can also serve as a receiving and buffering structure for the gas generated inside the battery cell assembly, reducing the expansion of the battery cell, and improving the reliability and stability of the battery cell; in addition, the first receiving groove is located on the inner side of the pole, and external foreign matter and impurities are not easy to enter the first receiving groove, thereby reducing the impact of external foreign matter and impurities on the battery cell assembly, ensuring the stability and reliability of the battery cell assembly, and thus improving the stability and reliability of the battery cell and the battery; the first receiving groove is located on the inner side of the pole, and at least part of the conductive part is accommodated in the first receiving groove, so as to limit the conductive part from the inside of the pole, and facilitate the connection of the conductive part with the first pole.

[0011] In some embodiments, the housing has a mounting hole, and the first pole is mounted in the mounting hole; along the axial direction of the first pole, the depth H1 of the first receiving groove is greater than or equal to the minimum distance H2 from the inner end surface of the pole to the mounting hole.

[0012] In the above technical solution, since the depth of the first accommodating groove is greater than or equal to the minimum distance from the inner end face of the pole to the mounting hole in the axial direction of the first pole, the volume of the first pole can be fully utilized, so that the first accommodating groove has a larger depth, which is conducive to accommodating more conductive parts, and thus can greatly reduce the space occupied by the conductive parts in the shell, further improve the energy density of the battery cell, and further reduce the redundancy of the conductive parts in the shell; at the same time, since the first accommodating groove has a larger depth, it can also accommodate the gas production of the battery cell assembly, ensure the reliability and stability of the battery cell, and can also accommodate more electrolyte to ensure the service life of the battery cell.

[0013] In some embodiments, the accommodating portion includes a first end wall and a first side wall, the first end wall is located on the side of the first side wall away from the active material coating portion, the first end wall and the first side wall are arranged to form a first accommodating groove, and the electrical connection position between the conductive portion and the first pole is located on the first end wall and / or the first side wall.

[0014] In the above technical solution, by arranging the electrical connection point between the conductive portion and the first terminal on at least one of the first end wall and the first side wall, the first receiving groove not only accommodates at least part of the conductive portion but also establishes an electrical connection with the conductive portion. This simplifies the structure of the first terminal, facilitates its processing, simplifies the structure of the conductive portion, reduces redundancy in the conductive portion, and reduces the cost of the conductive portion. Furthermore, by utilizing the groove wall of the first receiving groove to achieve electrical connection with the conductive portion, the area where the conductive portion is electrically connected to the first terminal can be relatively large, which not only reduces the difficulty of electrical connection but also improves the reliability and stability of the electrical connection, thereby enhancing the performance of the battery cell. When the electrical connection point between the conductive portion and the first terminal is located on the first end wall, it is convenient to connect the conductive portion and the first end wall from the outside.

[0015] In some embodiments, a first recessed groove is formed on the first end wall, and at least a portion of the location where the conductive portion is electrically connected to the first end wall is located in the first recessed groove.

[0016] In the above technical solution, on the one hand, by arranging the first recessed groove on the first end wall, the first recessed groove can be used to achieve pre-positioning of the conductive part, which is beneficial for finding the correct position to achieve electrical connection and improve production efficiency; on the other hand, by arranging the first recessed groove on the first end wall, the local wall thickness of the first end wall can be locally thinned, which is not only beneficial for welding electrical connection, but also beneficial for reducing the weight of the first pole and improving the weight energy density of the battery cell.

[0017] In some embodiments, the first pole has a first groove, a surface of the first pole away from the active material coating portion is an outer end surface of the pole, and a notch of the first groove is formed on the outer end surface of the pole.

[0018] In the above technical solution, on the one hand, the first electrode is provided with a first groove, which can further reduce the weight of the first electrode, thereby improving the weight energy density of the battery cell and the battery. On the other hand, the first groove is located on the outside of the first electrode, and can be used to accommodate or install structural components in the battery that electrically connect the various battery cells, thereby fully utilizing the space within the first electrode and improving the space utilization rate and volume energy density of the battery. In addition, because the first electrode has both the first receiving groove and the first groove, the first groove is located on the side of the first receiving groove away from the active material coating portion, and the first groove is open in a direction away from the first receiving groove. This facilitates electrical connection between the conductive portion and the groove wall of the first receiving groove from the outside of the first electrode through the first groove. For example, it is convenient to externally weld the first electrode and the conductive portion through the first groove, which facilitates the processing and manufacturing of the battery cell and can save processing and manufacturing costs.

[0019] In some embodiments, the housing assembly further includes a slot cover, which is disposed on the first pole and covers a slot opening of the first groove.

[0020] In the above technical solution, the provision of the slot cover facilitates electrical connection between adjacent battery cells within the battery. Furthermore, because the location where the battery cells are electrically connected is separated from the location where the conductive portion and the first terminal are electrically connected by the first groove, interference between the two is minimized, further improving the stability and reliability of the battery cells. Furthermore, the slot cover prevents foreign matter from entering the first groove, reducing interference with the battery cell assembly and further improving the reliability and stability of the battery cells.

[0021] In some embodiments, the accommodating portion has a second accommodating groove, the surface of the first pole away from the active material coating portion is the outer end face of the pole, the notch of the second accommodating groove is formed on the outer end face of the pole, the second accommodating groove is connected to the interior of the shell through the first through-hole, the conductive portion is passed through the first through-hole and is at least partially accommodated in the second accommodating groove.

[0022] In the above technical solution, on the one hand, the first electrode is provided with a second receiving groove, which can reduce the weight of the first electrode to a certain extent, so as to improve the weight energy density of the battery cell and the battery; on the other hand, since the notch of the second receiving groove is formed on the outer end face of the electrode, and the outer end face of the electrode is the surface of the first electrode away from the active material coating part, the second receiving groove can be open in the direction away from the active material coating part. In this way, when at least part of the conductive part is accommodated in the second receiving groove, the conductive part can be easily stored and sorted through the notch of the second receiving groove, or the conductive part can be electrically connected to the first electrode, etc., thereby reducing the difficulty of producing the battery cell and improving the production efficiency of the battery cell. At the same time, since the second receiving tank can be connected to the shell through the first perforation, the second receiving tank can also serve as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the shell. Since the battery cell will lose electrolyte during the charging and discharging process, when there is more electrolyte, the service life of the battery cell can be extended; and because the second receiving tank can be connected to the shell through the first perforation, the second receiving tank can also serve as a storage and buffer structure for gas generated inside the battery cell assembly, reducing the expansion of the battery cell and improving the reliability and stability of the battery cell.

[0023] In some embodiments, the electrical connection position between the conductive portion and the first pole is located on a hole wall of a first through-hole formed in the accommodating portion.

[0024] In the above technical solution, when the electrical connection position between the conductive part and the first pole is set on the hole wall of the first through-hole, the electrical connection operation between the conductive part and the first pole can be performed through the second receiving groove; at the same time, the electrical connection position between the conductive part and the first pole can realize the sealing of the first through-hole to save sealing costs and reduce electrolyte leakage.

[0025] In some embodiments, the accommodating portion includes a second end wall and a second side wall, the second end wall is located on a side of the second side wall close to the active material coating portion, the second end wall and the second side wall are arranged to form a second accommodating groove, the first through-hole is opened on the second end wall, and the electrical connection position between the conductive portion and the first pole is located on the second end wall and / or on the second side wall.

[0026] In the above technical solution, by setting the electrical connection position between the conductive part and the first pole on at least one of the second end wall and the second side wall, the second receiving groove not only has the function of accommodating at least part of the conductive part, but the groove wall of the second receiving groove also has the function of achieving electrical connection with the conductive part, thereby simplifying the structure of the first pole and facilitating the processing of the first pole. Moreover, since the first perforation is provided in the second end wall, it is convenient for the conductive part to extend into the second receiving groove through the first perforation, which can simplify the structure of the conductive part, reduce the redundancy of the conductive part, and reduce the cost of the conductive part. In addition, the opening direction of the notch of the second receiving groove makes it easy to electrically connect the conductive part to the groove wall of the second receiving groove through the notch of the second receiving groove, which can reduce the difficulty of electrical connection. Moreover, by using the groove wall of the second receiving groove to achieve electrical connection with the conductive part, the area where the conductive part is electrically connected to the first pole can be relatively large, which can improve the reliability and stability of the electrical connection, thereby improving the performance of the battery cell.

[0027] In some embodiments, a second recessed groove is formed on the second end wall, and at least a portion of the location where the conductive portion is electrically connected to the second end wall is located in the second recessed groove.

[0028] In the above technical solution, by providing the second sinking groove on the second end wall, the second sinking groove can be used to achieve pre-positioning of the conductive part, which is beneficial for finding the correct position to achieve electrical connection and improve production efficiency.

[0029] In some embodiments, the housing has a mounting hole, the first pole is mounted in the mounting hole, and along the axial direction of the first pole, the depth H3 of the second receiving groove is greater than or equal to the minimum distance H4 from the outer end surface of the pole to the mounting hole.

[0030] In the above technical solution, since the depth of the second accommodating groove is greater than or equal to the minimum distance from the outer end face of the pole to the mounting hole in the axial direction of the first pole, the volume of the first pole can be fully utilized, so that the second accommodating groove has a larger depth, which is conducive to accommodating more conductive parts, and thus can greatly reduce the space occupied by the conductive parts in the shell, further improve the energy density of the battery cell, and further reduce the redundancy of the conductive parts in the shell; at the same time, since the second accommodating groove has a larger depth, it can also accommodate the gas production of the battery cell assembly, improve the reliability and stability of the battery cell, and can also accommodate more electrolyte to increase the service life of the battery cell.

[0031] In some embodiments, the housing assembly further includes a first cover plate, the first cover plate cooperates with the first pole and closes the notch of the second receiving groove, and the first cover plate is electrically connected to the first pole.

[0032] In the above technical solution, by providing a first cover plate to close the notch of the second receiving tank, the electrolyte in the shell can be prevented from leaking from the notch of the second receiving tank. Moreover, since the first cover plate closes the notch of the second receiving tank and is electrically connected to the first electrode, the first cover plate can be used to easily achieve indirect electrical connection between the first electrode and the busbar of the battery, and it is beneficial to increase the connection area of ​​the electrical connection, thereby helping to reduce the resistance of the electrical connection.

[0033] In some embodiments, the first cover plate includes a first conductive member and a second conductive member made of different materials. The first conductive member cooperates with and is electrically connected to the first pole, and the second conductive member cooperates with and is electrically connected to the first conductive member.

[0034] In the above technical solution, the first cover is set to a composite form, and the first conductive member is set to be the same material as the first pole, so as to facilitate the electrical connection between the first conductive member and the first pole, and because the second conductive member is made of a different material from the first conductive member, it is convenient to use the second conductive member to electrically connect to the busbar component of the battery whose material is different from that of the first pole.

[0035] In some embodiments, the first conductive member has a second groove, the second conductive member is embedded in the second groove, and the notch of the second groove is formed on the surface of the first conductive member away from the second accommodating groove so that the second conductive member is exposed from the notch of the second groove.

[0036] In the above technical solution, on the one hand, by embedding the second conductive part in the first conductive part, the difficulty of assembling the first and second conductive parts can be reduced, the stability and convenience of the cooperation between the first and second conductive parts can be improved, and the thickness of the first cover plate can be reduced, reducing the space occupied by the first cover plate, thereby improving the space utilization rate of the battery cell. On the other hand, since the second conductive part can be exposed from the surface of the first conductive part away from the second receiving groove through the notch of the second groove, it is convenient to achieve electrical connection between the second conductive part and the battery busbar outside the first pole. In addition, since the notch of the second groove is formed on the surface of the first conductive part away from the second receiving groove, the first conductive part can be isolated between the second receiving groove and the second conductive part, so as to prevent the electrolyte entering the second groove from contacting the second conductive part, thereby reducing leakage of the electrolyte.

[0037] In some embodiments, the first cover plate is embedded in the notch of the second receiving groove.

[0038] In the above technical solution, by embedding the first cover plate within the second receiving groove, the difficulty of assembling the first cover plate and the first terminal can be reduced, the assembly stability, reliability, and convenience of the connection between the first cover plate and the first terminal can be improved, and the space occupied by the first cover plate outside the first terminal can be reduced. Moreover, because the first cover plate is embedded in the notch of the second receiving groove, there is sufficient space in the second receiving groove to accommodate the conductive part.

[0039] In some embodiments, the wall surface of the first pole at the notch of the second receiving groove is a guiding slope, and the guiding slope is used to guide the first cover plate to cooperate with the notch of the second receiving groove.

[0040] In the above technical solution, by processing the wall surface at the notch of the second receiving groove into a guiding inclined surface, the difficulty of assembling the first cover plate and the second receiving groove can be reduced, and the assembly efficiency of the first cover plate and the second receiving groove can be improved.

[0041] In some embodiments, the second accommodating groove includes a first groove section and a second groove section located on the side of the first groove section close to the outer end face of the pole, the cross-sectional area of ​​the second groove section is larger than the cross-sectional area of ​​the first groove section, so as to form a step surface between the first groove section and the second groove section, and the first cover plate is embedded in the second groove section and supported on the step surface.

[0042] In the above technical solution, by setting the second accommodating groove as a stepped groove form, the first cover plate can be stably fitted in the groove position of the second accommodating groove, thereby improving the connection stability between the first cover plate and the first pole, and by limiting the groove depth of the first groove section, there is relatively sufficient space in the second accommodating groove to accommodate the conductive part.

[0043] In some embodiments, the first pole includes a first pole portion and a second pole portion made of different materials and electrically connected, the second pole portion is located on the side of the first pole portion away from the active material coating portion, the accommodating portion is arranged on the first pole portion or on the first pole portion and the second pole portion, and the conductive portion is electrically connected to the first pole portion.

[0044] In the above technical solution, by setting the first pole as a composite form composed of different materials, the first pole part located on the inner side is accommodated and electrically connected to the conductive part, and the second pole part located on the outer side is electrically connected to the battery's busbar component, etc., which is conducive to the assembly and electrical connection of the first pole and related components, reduces the mutual interference between the electrical connection position of the pole and the conductive part and the electrical connection position of the pole and the battery's busbar component, and improves the reliability and stability of the battery cell.

[0045] In some embodiments, the accommodating portion has a fourth accommodating groove, the surface of the first pole away from the active material coating portion is the outer end face of the pole, the notch of the fourth accommodating groove is formed on the outer end face of the pole, the fourth accommodating groove is connected to the interior of the shell through the second perforation, the conductive portion is passed through the second perforation, and the electrical connection position between the conductive portion and the first pole is located on the hole wall of the second perforation formed in the accommodating portion.

[0046] In the above technical solution, by providing the fourth receiving groove, the electrical connection between the conductive portion and the wall of the second through hole can be easily achieved. In some cases, the electrical connection between the conductive portion and the first pole can be used to seal the second through hole.

[0047] In some embodiments, the battery cell further includes: a bracket located inside the shell and located on the side of the active material coating portion close to the first pole, the bracket having an avoidance hole for avoiding the conductive portion, and the conductive portion is suitable for extending to the side of the bracket away from the active material coating portion through the avoidance hole.

[0048] In the above technical solution, by providing the fourth receiving groove, the electrical connection between the conductive portion and the wall of the second through hole can be easily achieved. In some cases, the electrical connection between the conductive portion and the first pole can be used to seal the second through hole.

[0049] In some embodiments, the bracket is provided with a guide portion, the guide portion surrounds at least a portion of the avoidance hole, and the guide portion at least partially extends to the accommodating portion.

[0050] In the above technical solution, since the bracket has a guide portion that at least partially extends into the accommodating portion, and at least a portion of the avoidance hole is formed by the guide portion, at least a portion of the conductive portion can be easily received in the accommodating portion, thereby improving the assembly efficiency of the conductive portion; at the same time, through the provision of the guide portion, the cooperation between the bracket and the pole, and between the bracket and the conductive portion are tighter and more reliable, making the structure of the battery cell more compact, which is more conducive to improving the energy density of the battery cell.

[0051] In some embodiments, the edge of the stent facing away from the housing cover has a housing entry guide surface, which may include a curved surface and / or an inclined surface. In the above technical solution, the housing entry guide surface can serve as a guide, allowing the stent to be smoothly installed into the housing body. The stent enters the housing first, followed by the active material coating portion, thereby reducing the risk of the housing scratching the active material coating portion.

[0052] In some embodiments, the bracket is an integrated structure; or, the bracket is a split structure and includes a detachable first bracket and a detachable second bracket, and an avoidance hole is defined between the first bracket and the second bracket.

[0053] In the above technical solution, when the bracket is an integrated structure, the bracket is easy to process, has good reliability, and facilitates assembly of the bracket with the housing assembly, improving assembly efficiency and mating stability. When the bracket is a split structure, the first bracket and the second bracket cooperate to define an escape hole. When the bracket is assembled with the battery cell assembly, there is no need to pass the conductive portion from one end of the escape hole to the other. Instead, the first bracket and the second bracket can be spliced ​​together at the location of the conductive portion to clamp the conductive portion, so that the escape hole surrounds the conductive portion, thereby facilitating assembly of the bracket with the battery cell assembly and improving assembly efficiency.

[0054] In some embodiments, the battery cell further includes: an inner insulating member, which is located inside the shell and wrapped around the active material coating portion, and is connected to the bracket.

[0055] In the above technical solution, on the one hand, by wrapping the inner insulating part outside the active material coating part, the insulation reliability between the active material coating part and the shell can be improved, the corrosion of the shell caused by the contact between the active material coating part and the shell can be reduced or prevented, and the leakage of electrolyte caused by shell corrosion can be reduced, thereby improving the reliability of the battery cell; on the other hand, connecting the inner insulating part to the bracket can reduce the difficulty of fixing the inner insulating part and improve the reliability of the inner insulating part wrapped outside the active material coating part.

[0056] In some embodiments, the housing assembly includes at least one first pole riveted to the housing body.

[0057] In the above technical solution, since the first terminal is connected to the shell by riveting, welding is difficult when the shell is thin. However, riveting the first terminal to the shell is easier. That is, riveting the first terminal to the shell is simple to install and easy to operate. Moreover, riveting the first terminal to the shell facilitates a thinner and lighter shell design, thereby reducing the weight of the battery cell. When the battery cell size is fixed, riveting the first terminal facilitates thinning the shell, increases the internal space of the shell, and improves the energy density of the battery cell.

[0058] In some embodiments, a mounting hole is provided on the shell body, and the first pole includes an integrally formed pole body, a first limit platform and a second limit platform. The pole body is passed through the mounting hole, and the first limit platform and the second limit platform are arranged at both ends of the pole body along the axial direction of the mounting hole, and the first limit platform is limited to the outer side of the shell body, and the second limit platform is limited to the inner side of the shell body, so that the first pole is riveted to the shell body.

[0059] In the above technical solution, the first limiting platform and the second limiting platform respectively extend along the radial direction of the mounting hole to the radially outer side of the peripheral wall of the mounting hole. The first limiting platform can limit the movement of the first pole relative to the shell body in the direction toward the inner side of the shell body, and the second limiting platform can limit the movement of the first pole relative to the shell body in the direction toward the outer side of the shell body, so that the first pole can be easily and reliably mounted at the mounting hole through the first limiting platform and the second limiting platform, which is conducive to the riveting of the first pole and the shell body and the assembly of the first pole and the shell body. In addition, no other connection method is required between the first pole and the shell body, which can facilitate the reliable connection of the first pole and the shell body, and is conducive to simplifying the structure of the shell assembly and simplifying the assembly process of the shell assembly. At the same time, the pole body, the first limiting platform and the second limiting platform of the first pole are integrally formed, which can save parts and costs and ensure the strength of the first pole. After the first pole is matched with the shell, it is not easy to separate from the shell due to vibration or external pulling during the charging and discharging process of the battery cell, nor is it easy to crack or damage due to vibration or external pulling, which can improve the stability and reliability of the battery cell.

[0060] In some embodiments, a dimension of the first pole in the first direction is greater than a dimension of the first pole in the second direction, the first direction and the second direction are perpendicular, and both the first direction and the second direction are perpendicular to the axial direction of the mounting hole.

[0061] In the above technical solution, on the plane formed by the first direction and the second direction, the shape of the orthographic projection of the first pole can be non-circular, which is conducive to achieving good matching between the first pole and the wall of the shell body on which the first pole is arranged in the first direction and the second direction. To a certain extent, the cross-sectional area of ​​the first pole that can be arranged on the above-mentioned wall of the shell body can be increased, which is conducive to increasing the flow area of ​​the first pole within the limited arrangement area on the above-mentioned wall, improving the flow capacity of the first pole, and improving the heat diffusion capacity of the first pole, which is conducive to improving the charging speed of the battery cell using this shell assembly.

[0062] In some embodiments, the housing has a second wall portion and a third wall portion that are opposite to each other, and both the second wall portion and the third wall portion are provided with at least one first pole.

[0063] In the above technical solution, the first terminals can be provided on two opposing sides of the housing. When first terminals are provided on opposite sides of the housing, the conductive portion can extend from the active material coating portion near the first terminal on each side. The conductive portion can be cooperatively connected with the first terminal on the adjacent side. This can alleviate the problem of the terminal ear being pulled by the first terminal on the same side, causing cracking of the connection between the terminal ear and the active material coating portion, thereby improving the reliability of the battery cell. It is worth noting that the first terminals on both sides can be identical or different, and the connection method between the first terminals and the conductive portion can be the same or different, without limitation herein.

[0064] In some embodiments, the shell body has multiple walls, a middle portion of the multiple walls is a first set wall, the area of ​​the first set wall is larger than that of the remaining walls, and the first pole is provided on the first set wall.

[0065] In the above technical solution, that is, the first pole is riveted to the largest wall of the shell body. Since the wall area connected to the first pole is the largest, the first pole is easier to operate when riveting, which can improve assembly efficiency and increase the quality rate of battery cells.

[0066] In some embodiments, the shell has multiple walls, at least one of which is a second set wall, the battery cell also includes a pressure relief portion, the pressure relief portion is arranged on the second set wall, and the first pole is arranged on the remaining walls except the second set wall.

[0067] In the above technical solution, the first pole and the pressure relief portion are arranged on different wall portions. When thermal runaway occurs in the battery cell, the discharged high-temperature medium will not come into contact with the first pole after being discharged through the pressure relief portion. This can reduce the probability of fire caused by contact between the circuit in the battery and the high-temperature medium.

[0068] In some embodiments, the battery cell further includes a pressure relief portion, which is provided on the shell cover, and the pressure relief portion and the shell cover are integrally formed.

[0069] In the above solution, the integral molding of the pressure relief portion and the shell cover can reduce the number of parts of the entire battery cell, thereby reducing the number of welding steps between the pressure relief portion and the shell body, that is, there is no step of connecting the pressure relief portion after or before the shell cover is connected to the shell body. This can improve the assembly efficiency of the battery cell, reduce the welding process cost, reduce the possibility of failure at the welding position, and improve the reliability of the battery cell.

[0070] In some embodiments, the housing has a plurality of walls, at least one of which is a first wall, the first pole is riveted to the first wall, and the thickness of the first wall is greater than that of the remaining walls.

[0071] In the above technical solution, the first wall portion serves as the shell wall connecting the first pole, and the thickness of the first wall portion is greater than that of the other wall portions. On the one hand, due to the relatively large thickness of the first wall portion itself, the overall strength of the shell body can be improved, thereby improving the reliability of the battery cell during daily use. On the other hand, due to the relatively large thickness of the first wall portion, the reliability of the riveting of the first pole can also be improved, thereby improving the quality rate of the battery cell. Secondly, under the premise of meeting the reliability of the riveting of the first pole, the thickness of the first wall portion can be a normal wall thickness, while the wall thickness of the other wall portions can be thinned. In this way, the space inside the shell body can be increased while the outer contour size of the shell body is fixed, thereby being able to place a larger active material coating portion, which is beneficial to improving the energy density of the battery cell.

[0072] In some embodiments, the thickness of the housing cover is less than the thickness of the first wall portion.

[0073] In the above technical solution, since the first pole is riveted to the first wall portion, and the shell cover does not need to be connected to the first pole, the strength requirement of the shell cover is relatively low, and its thickness can be smaller than the thickness of the first wall portion. This can save materials. Similarly, when the outer contour size of the shell is fixed, the thickness of the shell cover is relatively small, so the space inside the shell can be increased. At this time, the shell can accommodate a larger active material coating part, which is beneficial to improving the energy density of the battery cell.

[0074] In some embodiments, the thickness of the housing cover is greater than the thickness of the remaining wall portions except the first wall portion and adjacent to the housing cover.

[0075] In the above technical solution, considering that the shell cover needs to be closed on the opening, it is necessary to provide appropriate strength. Therefore, by setting the thickness of the shell cover to be greater than the thickness of the remaining walls adjacent to the shell cover except the first wall portion, the overall strength of the shell can be better after the shell cover is closed on the opening, which can reduce the probability of shell damage and improve the reliability of the battery cell.

[0076] In some embodiments, the opening is located at the bottom of the housing.

[0077] In the above technical solution, since the opening of the shell body is set at the top in the related technology, and the shell cover is installed on the opening at the top of the shell body, a processing chamfer will be left at the bottom of the internal space of the shell body during processing of the shell body with this structure. Then, when the active material coating part is installed into the shell, due to the existence of the processing chamfer, the bottom of the active material coating part (which may refer to the end of the active material coating part away from the conductive part) and the processing chamfer inside the shell body do not contact, and a certain space is left between the two. A partition will be set in the space to separate the active material coating part and the shell cover, which results in waste of space inside the shell body. It can be understood that, in this application, since the opening is provided at the bottom of the shell body, and the first pole is riveted to the shell body, in this shell structure, after the active material coating part enters the shell, there is no processed chamfer between the bottom of the active material coating part and the shell cover, that is, the partition between the bottom of the active material coating part and the shell cover can be omitted, and the gap between the bottom of the active material coating part and the shell cover can be greatly reduced, which is beneficial to increase the size of the active material coating part and improve the energy density of the battery cell. On the other hand, since there is no processed chamfer near the bottom of the active material coating part, the probability of damage due to accidental contact between the active material coating part and the processed chamfer can be greatly reduced, thereby reducing the loss of the active material coating, improving the performance of the battery cell, and also reducing the stress concentration at the corners of the active material coating part.

[0078] On the other hand, since the shell cover is arranged at the bottom of the shell body, when the battery cells are assembled into a battery, the bottom of the shell generally needs to be fixed to the bottom of the battery box. In this case, when vibration occurs during use, since the shell cover is connected to the bottom of the box, the amplitude of the connection between the shell cover and the shell body is relatively small, which can further reduce the probability of cracking of the shell cover and the shell body.

[0079] In some embodiments, the active material coating portion has a first end face close to the shell cover, and the battery cell also includes an internal insulating member, which covers the battery cell assembly, and at least a portion of the internal insulating member is arranged between the first end face and the shell cover. The internal insulating member has a first surface and a second surface relative to each other, the first surface contacts the first end face, and the second surface contacts the shell cover.

[0080] In the above technical solution, the first surface of the inner insulating part contacts the first end face, and the second surface contacts the shell cover. That is to say, while satisfying the insulation requirements of the active material coating part and the shell cover, the present application can eliminate the support plate between the active material coating part and the shell cover in the related technology, thereby saving space inside the shell body, increasing the size of the active material coating part, and further improving the energy density of the battery cell.

[0081] In some embodiments, the housing has a first wall portion opposite to the housing cover, and the first pole is provided on the first wall portion.

[0082] In the above technical solution, the battery cell assembly enters along the opening in this way, and the conductive part is directly opposite to the first pole, so that the conductive part can be connected to the first pole relatively easily, thereby improving the assembly efficiency of the battery cell.

[0083] In a second aspect, an embodiment of the present application further provides a battery comprising the above-mentioned battery cell.

[0084] In the above technical solution, in the battery, since the first poles of any adjacent battery cells are connected to each other, when the battery vibrates or deforms, the first poles between any adjacent battery cells will pull each other. At this time, since the first poles are arranged on the shell body, the force acting on the first poles will be preferentially transmitted to the shell body, and will not directly act on the shell cover. On the one hand, the distance for the force to be transmitted to the connection position between the shell body and the shell cover can be extended. On the other hand, when subjected to force, the shell body will preferentially deform to reduce the force at the connection position between the shell body and the shell cover, effectively reducing the probability of cracking between the shell cover and the shell body during battery use, and improving the reliability of the battery cell.

[0085] In a third aspect, an embodiment of the present application further provides an electrical device comprising the above-mentioned battery cell or battery.

[0086] In the above technical solution, the electrical device adopts the above-mentioned battery or battery cell. During use, the probability of cracking between the shell cover and the shell body of the battery cell is relatively low, which improves the reliability of the battery and is conducive to improving the performance of the electrical device.

[0087] Fourthly, an embodiment of the present application also provides an assembly method for a battery cell, wherein the battery cell includes a shell assembly and a cell assembly, the shell assembly includes a shell and a first pole, the shell includes a shell body and a shell cover, and the cell assembly includes an active material coating portion and a conductive portion. The assembly method includes: installing the cell assembly into the shell body; overlapping the conductive portion with the first pole; welding the conductive portion to the first pole from the outside of the shell body; and covering the shell cover on the shell body.

[0088] In the above technical solution, when assembling the battery cell of the present application, only the cell assembly is inserted into the shell. This reduces the number of parts inserted into the shell and reduces their weight (in the related art, the cell assembly, shell cover, and terminal need to be assembled before being inserted into the shell together). Therefore, inserting the cell assembly into the shell is relatively easy to operate, and it is also convenient to overlap the conductive portion with the first terminal, resulting in relatively high assembly efficiency. Due to the limited internal space of the shell body, welding the conductive portion from the outside of the shell body to the first terminal facilitates welding operations and improves assembly efficiency. Welding from the outside can effectively prevent metal foreign matter generated during welding from entering the interior of the battery cell, reducing the possibility of metal foreign matter causing internal short circuits in the battery cell. It also facilitates the cleaning of metal foreign matter generated during welding. Finally, the shell cover is placed on the shell body to complete the assembly.

[0089] Secondly, the assembly method of the present application only requires the steps of installing the battery cell assembly into the shell body; overlapping the conductive part with the first pole; welding the conductive part to the first pole from the outside of the shell body; and closing the shell cover on the shell body to complete the assembly of the battery cell. The overall assembly steps are relatively few, which can simplify the assembly process, reduce assembly time, and thus help reduce the manufacturing cost of the battery cell.

[0090] In some embodiments, the battery cell further includes a bracket, the edge of which has a shell entry guide surface, and the step of installing the battery cell assembly into the shell body includes: installing the bracket to the side of the active material coating portion close to the first pole, so that the shell entry guide surface is located on the side of the bracket away from the active material coating portion; and installing the battery cell assembly into the shell body under the guidance of the shell entry guide surface.

[0091] In the above technical solution, during assembly, the bracket can be pre-assembled with the battery cell assembly, and then this pre-assembled assembly can be installed into the shell. During installation, the bracket is located at the front end of the active material coating portion, that is, the bracket enters the shell before the active material coating portion. This can reduce the difficulty of the bracket entering the shell by utilizing the shell entry guide surface, and the bracket is used to protect the active material coating portion, reducing the chance of scratching and damage between the active material coating portion and the shell, thereby improving assembly efficiency and product quality. In addition, the contact area between the bracket and the active material coating portion can be increased, which can reduce stress concentration problems and eliminate other structural parts.

[0092] In some embodiments, the battery cell further includes a bracket having an avoidance hole; the step of overlapping the conductive portion with the first pole includes: passing the conductive portion through the avoidance hole; and overlapping the conductive portion with the first pole.

[0093] In the above technical solution, the bracket is used to separate the active material coating part from the shell, which is beneficial to improving the reliability of the battery cell, and an avoidance hole is provided on the bracket, which can guide and constrain the conductive part to cooperate with the first pole by passing through the avoidance hole, so that during the assembly process of the battery cell, there is no need for the conductive part to bypass the edge of the bracket to approach the first pole, which not only simplifies the arrangement of the conductive part, saves the material of the conductive part, and reduces the cost, but also supports and guides the conductive part to cooperate with the first pole by the bracket, which can reduce the risk of short-circuit connection between the conductive part and the active material coating part, thereby further improving the reliability of the battery cell.

[0094] In some embodiments, the first pole has a first receiving groove, the surface of the first pole facing the active material coating portion is the inner end face of the pole, and the groove opening of the first receiving groove is formed on the inner end face of the pole; the step of overlapping the conductive part with the first pole includes: extending the conductive part into the first receiving groove; overlapping the conductive part with the groove wall of the first receiving groove.

[0095] In the above technical solution, during the process of overlapping the conductive part with the first pole, since the first pole has the first accommodating groove, the conductive part is relatively easy to be accurately positioned with the first pole. In this way, when the conductive part is welded to the first pole from the outside of the shell body, the stability of the conductive part on the first pole can be improved, the welding quality can be improved, and the performance of the battery cell can be improved.

[0096] In some embodiments, the first pole has a second accommodating groove, the surface of the first pole away from the active material coating part is the outer end face of the pole, the notch of the second accommodating groove is formed on the outer end face of the pole, and the second accommodating groove is connected to the interior of the shell through a first through-hole; the step of overlapping the conductive part with the first pole includes: passing the conductive part out of the first through-hole to be at least partially accommodated in the second accommodating groove; overlapping the conductive part with the groove wall of the second accommodating groove and / or the hole wall of the first through-hole.

[0097] In the above technical solution, the second receiving groove can make the overlapping part of the conductive part and the first pole exposed outside the shell, which makes it easy to weld the conductive part and the first pole from the outside, which is easy to operate and helps to improve assembly efficiency.

[0098] In some embodiments, the battery cell further includes a first cover plate; after welding the conductive portion to the first pole, the assembly method further includes: welding the first cover plate to the first pole to close the notch of the second receiving groove.

[0099] In the above technical solution, by providing the first cover plate to seal the notch of the second receiving tank, leakage of electrolyte within the housing through the notch of the second receiving tank can be prevented. Furthermore, because the first cover plate seals the notch of the second receiving tank and is electrically connected to the first terminal, the first cover plate can be used to easily achieve indirect electrical connection between the first terminal and the busbar, thereby increasing the connection area of ​​the electrical connection and thereby reducing the resistance of the electrical connection. Furthermore, the first cover plate can separate the welded portion between the conductive portion and the first terminal from the welded portion between the first terminal and the busbar, reducing the impact of the welded portion between the conductive portion and the first terminal on the welded portion between the first terminal and the busbar, thereby improving the weld quality between the first terminal and the busbar. BRIEF DESCRIPTION OF THE DRAWINGS

[0100] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0101] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0102] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0103] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0104] FIG4 is a cross-sectional view of the internal structure of FIG3 taken along the AA direction;

[0105] FIG5 is a partial enlarged schematic diagram of point I in FIG4;

[0106] FIG6 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0107] FIG7 is an orthographic view of a battery cell provided in some embodiments of the present application;

[0108] FIG8 is a cross-sectional view along line AA in FIG7;

[0109] FIG9 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0110] FIG10 is an assembly diagram of a second electrode, a cell assembly, and a housing provided in some embodiments of the present application;

[0111] FIG11 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0112] FIG12 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0113] FIG13 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0114] FIG14 is a partial cross-sectional schematic diagram of a battery cell assembly provided in some embodiments of the present application;

[0115] FIG15 is a diagram illustrating various tab folding schemes for battery cell assemblies provided in some embodiments of the present application;

[0116] FIG16 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0117] FIG17 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0118] FIG18 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0119] FIG19 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0120] FIG20 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0121] FIG21 is a partial enlarged view of point B in FIG6 ;

[0122] FIG22 is an orthographic projection view of various first poles provided in some embodiments of the present application;

[0123] FIG23 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0124] FIG24 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0125] FIG25 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0126] FIG26 is an exploded view of the structure of a battery cell provided by some embodiments of the present application;

[0127] FIG27 is a partial cross-sectional schematic diagram of a housing assembly provided in some embodiments of the present application;

[0128] FIG28 is an exploded view of the structure of the housing assembly shown in FIG27;

[0129] FIG29 is an exploded view of the structure of the first cover plate shown in FIG28;

[0130] FIG30 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0131] FIG31 is an exploded view of the structure of the battery cell shown in FIG30 ;

[0132] FIG32 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0133] FIG33 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0134] FIG34 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0135] FIG35 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0136] FIG36 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0137] FIG37 is a schematic diagram of the cooperation between a battery cell assembly and a bracket provided in some embodiments of the present application;

[0138] FIG38 is a cross-sectional view taken along line CC in FIG37;

[0139] FIG39 is a schematic structural diagram of an integrated bracket provided in some embodiments of the present application;

[0140] FIG40 is a schematic structural diagram of a split bracket provided in some embodiments of the present application;

[0141] FIG41 is a partial cross-sectional schematic diagram of a battery cell assembly and a bracket provided in some embodiments of the present application;

[0142] FIG42 is an exploded view of the structure of a battery cell assembly, a bracket, and a housing assembly provided in some embodiments of the present application;

[0143] FIG43 is an exploded view of the structure of the first pole, the housing, and the sealing gasket provided in some embodiments of the present application;

[0144] FIG44 is an assembly diagram of the first pole, housing, and sealing gasket shown in FIG43;

[0145] FIG45 is a schematic structural diagram of a first pole provided in some embodiments of the present application;

[0146] FIG46 is an assembly diagram of the first pole, housing, and sealing gasket shown in FIG45 ;

[0147] FIG47 is an exploded view of the structure of the first pole shown in FIG45;

[0148] FIG48 is an orthographic view of a battery cell provided by some embodiments of the present application;

[0149] FIG49 is an orthographic view of a battery cell provided by some embodiments of the present application;

[0150] FIG50 is a cross-sectional view along line DD in FIG49;

[0151] FIG51 is a schematic cross-sectional view of a housing assembly provided in some embodiments of the present application;

[0152] FIG52 is a schematic cross-sectional view of a housing assembly provided in some embodiments of the present application;

[0153] FIG53 is an orthographic view of a battery cell provided by some embodiments of the present application;

[0154] FIG54 is a cross-sectional view taken along line EE in FIG53;

[0155] FIG55 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0156] FIG56 is a schematic structural diagram of a housing cover provided in some embodiments of the present application;

[0157] FIG57 is a second structural diagram of a battery cell provided in some embodiments of the present application;

[0158] FIG58 is a third structural diagram of a battery cell provided by some embodiments of the present application;

[0159] FIG59 is a partial enlarged schematic diagram of point II in FIG4;

[0160] FIG60 is a top view of a battery cell provided in some embodiments of the present application;

[0161] FIG61 is a flowchart of a battery cell assembly method according to some embodiments of the present application;

[0162] FIG62 is a second flowchart of a battery cell assembly method according to some embodiments of the present application;

[0163] FIG63 is a flowchart diagram 3 of a battery cell assembly method according to some embodiments of the present application;

[0164] FIG64 is a fourth flowchart of a battery cell assembly method according to some embodiments of the present application;

[0165] FIG65 is a flowchart diagram 5 of a battery cell assembly method according to some embodiments of the present application;

[0166] FIG66 is a flowchart six of the battery cell assembly method provided in some embodiments of the present application.

[0167] Icons: Electric device 1000; Battery 100; Controller 200; Motor 300; First direction Z; Second direction X; Third direction Y; Axial direction R of first pole; Battery cell 10; Housing 20; First housing 201; Second housing 202; Housing assembly 1; Housing 11; First wall 110; Housing 111; Opening 111a; Wall 1111; First wall 1112; Second wall 1113; Third wall 1114; Wall 1115; First setting wall 1116; Housing cover 112; Liquid reservoir 112a; First groove 1121; Second groove 1122; Third groove 1123; Protrusion 112b; Mounting hole 113; First pole 12; Accommodation portion 121; First receiving groove 12110; first end wall 12111; first recess 12112; first side wall 12113; second receiving groove 12120; second end wall 12121; second recess 12122; second side wall 12123; first groove section 12124; second groove section 12125; guide slope 12126; stepped surface 12127; first through-hole 12130; third receiving groove 12140; fourth receiving groove 12150; second through-hole 12160; third through-hole 12170; pole inner end surface 122; pole outer end surface 123; first pole portion 124; second pole portion 125; first groove 126; spacer 127; stopper 1281; through-hole 1282; flanged portion 1283; first portion 1291; second portion 1292; First cover plate 13; first conductive member 131; second groove 1311; second conductive member 132; stress relief groove 133; second cover plate 14; second electrode 15; pressure relief portion 16; avoidance groove 18; first sealing gasket 191; second sealing gasket 192; battery cell assembly 2; electrode assembly 2a; active material coating portion 21; first end surface 21a; current collector 211; active material layer 212; conductive portion 22; electrode tab 221; electrode tab 2211; first folded portion 2212; second folded portion 2213; adapter 222; bracket 3; avoidance hole 31; first hole section 311; second hole section 312; guide portion 32; first bracket 33; second bracket 34; shell entry guide surface 35; body portion 36; extension portion 37; third groove 38; positioning groove 39; Inner insulator 4 ; main body 41 ; connecting portion 42 ; first surface 4 a ; second surface 4 b ; sealing member 6 ; slot cover 7 . DETAILED DESCRIPTION

[0168] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0169] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0170] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0171] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0172] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0173] The term "plurality" used in this application refers to two or more (including two).

[0174] In this application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application do not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0175] The battery mentioned in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may be a battery module or a battery pack. When the battery is a battery module, the battery module is composed of multiple battery cells. When the battery is a battery pack, the battery pack can be directly composed of a box and multiple battery cells arranged in the box; or the battery module can be first composed of battery cells, and then the battery module is arranged in the box. The box can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0176] For example, a battery cell typically includes a housing, an electrode assembly, and an electrolyte. The housing houses the electrode assembly and electrolyte and is provided with at least one positive electrode post and at least one negative electrode post. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. The separator can be made of any material, for example, polypropylene or polyethylene.

[0177] The positive electrode sheet can generally include a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is directly or indirectly coated on the positive electrode current collector. The positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer. The positive electrode current collector not coated with the positive electrode active material layer serves as the positive electrode tab.

[0178] The negative electrode sheet generally includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is directly or indirectly coated on the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as the negative electrode tab sheet.

[0179] The electrode assembly can be a wound or laminated structure. During processing, the positive electrode sheet, negative electrode sheet, and separator are sequentially wound or laminated to form an electrode assembly. In the electrode assembly, multiple positive electrode tabs are stacked together and electrically connected to the positive electrode post, and multiple negative electrode tabs are stacked together and electrically connected to the negative electrode post.

[0180] Battery cells primarily rely on the movement of metal ions between the positive and negative electrodes to function. Taking lithium-ion batteries as an example, the positive current collector can be made of aluminum, and the positive active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The negative current collector can be made of copper, and the negative active material layer can be made of carbon or silicon. During the charge and discharge process, Li+ is intercalated and deintercalated back and forth between the two electrodes: during charging, Li+ is deintercalated from the positive electrode and then intercalated into the negative electrode through the electrolyte, leaving the negative electrode in a lithium-rich state; the opposite occurs during discharge.

[0181] In recent years, new energy vehicles have experienced rapid development. In the electric vehicle sector, batteries, as the power source of electric vehicles, play an irreplaceable and important role. As core components of new energy vehicles, batteries have high requirements in terms of both energy density and reliability.

[0182] In the related art, during the manufacturing of battery cells, an active material layer is coated on the current collector and then cut to obtain a pole piece consisting of a current collector coated with an active material layer (referred to as the active material coating portion) and a current collector not coated with an active material layer (referred to as the pole tab piece). The positive and negative pole pieces and the separator are then stacked or wound in sequence to obtain a battery cell assembly. In the electrode assembly, multiple pole tabs are stacked to form the pole tab portion. The pole tab portion is connected to the adapter to form a conductive portion, or the pole tab portion itself forms a conductive portion; the active material coating portion and the conductive portion form a battery cell assembly. The battery cell shell is provided with a pole post. During the manufacturing of the battery cell, the conductive portion is usually welded to the pole post to ensure the normal charging and discharging operations.

[0183] However, the inventors discovered that in the related art, the top of the housing has an opening, and the poles are mounted on the housing cover. The housing cover is then welded to the housing, with the weld located at the top of the battery cell. However, when the battery cells are assembled into a battery, the bottom of the housing needs to be fixed, and the poles of adjacent battery cells are connected by conductive components (such as busbars). Because the poles are mounted on the housing cover, if the battery vibrates or deforms during use, the conductive components will pull on the poles. The pulling force of the conductive components on the poles can easily be transmitted to the weld between the housing cover and the housing, causing material fatigue and cracking at the weld, thereby affecting the reliability of the battery cells.

[0184] Based on the above considerations, in order to improve the reliability of the battery cell, the inventors have found that by changing the installation position of the pole and setting the pole on the shell, the shell cover in the battery cell will not be directly connected to the pole. In this way, when the battery cells are pulled against each other due to vibration or deformation during the use of the battery, at this time, since the first pole is set on the shell, the force acting on the first pole will be transmitted to the shell first, and will not act directly on the shell cover; on the one hand, the distance for the force to be transmitted to the weld between the shell body and the shell cover can be extended, and on the other hand, when subjected to force, the shell body will deform first to reduce the force at the weld between the shell body and the shell cover, effectively reducing the probability of cracking at the weld between the shell body and the shell cover during the use of the battery, and improving the reliability of the battery cell.

[0185] The present application provides an electrical device using the battery cell of the present disclosure as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, and the like. 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, and the like. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like.

[0186] For the convenience of explanation, the following embodiments are described using an electric device in one embodiment of the present application as a vehicle as an example. Please refer to Figure 1, which is a structural schematic diagram of an electric device 1000 provided in some embodiments of the present application as a vehicle. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle, and the battery 100 can be provided at the bottom, head or tail of the vehicle. The battery 100 can be used to power the vehicle, for example, the battery 100 can serve as the operating power source of the vehicle. The vehicle 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 during driving. In some embodiments of the present application, the battery 100 can not only serve as the operating power source of the vehicle, but also as the driving power source of the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0187] Please refer to Figure 2, which is an exploded view of the structure of the battery cell 10 provided in some embodiments of the present application. The battery 100 includes a housing 20 and a plurality of battery cells 10, and the battery cells 10 are accommodated in the housing 20. The housing 20 is used to provide an assembly space for the battery cells 10, and the housing 20 can adopt a variety of structures. In some embodiments, the housing 20 can include a first housing 201 and a second housing 202, which cover each other and together define an assembly space for accommodating the battery cells 10. The second box body 202 can be a hollow structure with one end open, and the first box body 201 can be a plate-like structure. The first box body 201 covers the open side of the second box body 202, so that the first box body 201 and the second box body 202 jointly define an assembly space. The first box body 201 and the second box body 202 can also be hollow structures with one end open, and the open side of the first box body 201 covers the open side of the second box body 202. Of course, the box body 20 formed by the first box body 201 and the second box body 202 can be of various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0188] In the battery 100, multiple battery cells 10 can be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections among the multiple battery cells 10. Multiple battery cells 10 can be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure of the multiple battery cells 10 is housed within the housing 20. Alternatively, the battery 100 can be constructed by first connecting multiple battery cells 10 in series, in parallel, or in a hybrid configuration to form a battery module, which is then connected in series, in parallel, or in a hybrid configuration to form a single structure housed within the housing 20. The battery 100 may also include other structures, such as a busbar for electrically connecting the multiple battery cells 10.

[0189] Please refer to Figure 3, which is a schematic diagram of a battery cell 10 provided in some embodiments of the present application. The battery cell 10 is a rectangular parallelepiped, with the height of the battery cell 10 being in a first direction Z, the thickness of the battery cell 10 being in a second direction X, and the length of the battery cell being in a third direction Y. The first direction Z, the second direction X, and the third direction Y are mutually perpendicular. However, this is not limiting. In other embodiments of the present application, the battery cell 10 may also be cylindrical, flat, or have other shapes.

[0190] As shown in FIG. 3 to FIG. 6 , the battery cell 10 includes a housing assembly 1 and a cell assembly 2 .

[0191] The housing assembly 1 includes a housing 11 and a first electrode 12. The housing 11 includes a body 111 and a cover 112. The body 111 has an opening 111a, and the cover 112 covers the opening 111a. The body 111 is provided with the first electrode 12. The cell assembly 2 includes an active material coating portion 21 and a conductive portion 22. The active material coating portion 21 is accommodated in the body 111, and the conductive portion 22 electrically connects the active material coating portion 21 and the first electrode 12.

[0192] The housing 11 is provided with poles, which are used to electrically connect to the battery cell assembly 2 to ensure the normal charging and discharging operations of the battery cell 10. Generally, there are at least two poles, specifically at least one positive pole and at least one negative pole. For example, when there are two poles, one is a positive pole and the other is a negative pole, and the two are electrically connected to the positive and negative output positions of the battery cell assembly 2 respectively; for another example, when there are four poles, two can be positive poles and two can be negative poles. At least one of the multiple poles is a first pole 12, which can serve as either a positive pole or a negative pole.

[0193] In an embodiment of the present application, the battery cell assembly 2 includes an active material coating portion 21 and a conductive portion 22. The active material coating portion 21 is accommodated in the shell 11. The active material coating portion 21 is the portion of the battery cell assembly 2 coated with active material, which can assist in the deintercalation of metal ions during the charging and discharging process of the battery cell 10. The conductive portion 22 is a metal structure that electrically connects the active material coating portion 21 and the pole. It is not coated with active material and can be electrically connected to the active material coating portion 21 through the conductive portion 22 to enable the charging and discharging operations of the battery cell 10 to be carried out.

[0194] The active material coating portion 21 is divided into a positive electrode active material coating portion and a negative electrode active material coating portion. The positive electrode active material coating portion includes the portion of the positive electrode current collector coated with the positive electrode active material layer, while the negative electrode active material coating portion includes the portion of the negative electrode current collector coated with the negative electrode active material layer. The conductive portion 22 is divided into a positive electrode conductive portion and a negative electrode conductive portion. The positive electrode conductive portion electrically connects the positive electrode active material coating portion to the positive electrode post, while the negative electrode conductive portion electrically connects the negative electrode active material coating portion to the negative electrode post.

[0195] In the above technical solution, in the battery 100, since the first poles 12 of any adjacent battery cells 10 are connected to each other, when the battery 100 vibrates or deforms, the first poles 12 between any adjacent battery cells 10 will pull on each other. At this time, since the first poles 12 are arranged on the shell body 111, the force acting on the first poles 12 will be preferentially transmitted to the shell body 111, and will not directly act on the shell cover 112. On the one hand, the distance for the force to be transmitted to the weld between the shell body 111 and the shell cover 112 can be extended. On the other hand, when subjected to force, the shell body 111 will preferentially deform to reduce the force on the weld between the shell body 111 and the shell cover 112, effectively reducing the probability of cracking at the weld between the shell cover 112 and the shell body 111 during use of the battery, and improving the reliability of the battery cell 10.

[0196] In the embodiment of the present application, referring to FIG. 7 and FIG. 8 , the first pole 12 is provided with a receiving portion 121 , and at least a portion of the conductive portion 22 is received in the receiving portion 121 .

[0197] With reference to the foregoing, there can be multiple poles, at least one of which is a first pole 12, the first pole 12 being a pole formed with an accommodating portion 121, the accommodating portion 121 being a virtual structure having an accommodating space, which can be a slot-shaped structure, a hole-shaped structure, or a composite structure of a slot-shaped structure and a hole-shaped structure. In other words, all the poles on the shell 11 can be first poles 12 formed with an accommodating portion 121, or a portion of the poles on the shell 11 can be first poles 12 formed with an accommodating portion 121. When a portion of the poles on the shell 11 are first poles 12 formed with an accommodating portion 121, the remaining poles on the shell 11 are second poles 15 without an accommodating portion 121 (see Figures 9 and 10). The term "at least partially" means that the conductive portion 22 can be completely accommodated in the accommodating portion 121, or a portion of the conductive portion 22 can be partially accommodated in the accommodating portion 121. Since the first electrode 12 is provided with the receiving portion 121 , the hollow structure of the receiving portion 121 can reduce the weight of the electrode 12 to a certain extent, thereby improving the weight energy density of the battery cell 10 and the battery 100 .

[0198] Furthermore, by partially or entirely containing the conductive portion 22 within the accommodating portion 121, the portion of the conductive portion 22 located within the accommodating portion 121 can occupy the space within the first electrode 12, thereby reducing the space occupied by the conductive portion 22 within the housing 11. When the size of the housing 11 is fixed, some space can be saved within the housing 11 to accommodate a larger active material coating portion 21, thereby improving the volumetric energy density of the battery cell 10. For example, when the conductive portion 22 is extended from the side of the active material coating portion 21 close to the first electrode 12, the space occupied by the conductive portion 22 between the active material coating portion 21 and the first electrode 12 can be reduced, thereby increasing the size of the active material coating portion 21 in the direction in which the conductive portion 22 is extended, reducing the distance between the active material coating portion 21 and the first electrode 12, and thus improving the energy density of the battery cell 10.

[0199] In addition, by accommodating at least part of the conductive part 22 in the accommodating portion 121, the space occupied by the battery cell 10 itself can be reduced, so that the battery 100 of the same volume can accommodate a larger number of battery cells 10, thereby also improving the volume energy density of the battery 100; in addition, at least part of the conductive part 22 is accommodated in the accommodating portion 121 to occupy the space in the first pole 12, so that the redundancy of the conductive part 22 in the shell 11 can be reduced to at least a certain extent, the probability of short circuit between the conductive part 22 and the active material coating part 21 is reduced, the probability of short circuit of the battery cell 10 is reduced, and the working reliability and stability of the battery cell 10 and the battery 100 are improved; at least part of the conductive part 22 is accommodated in the accommodating portion 121 of the first pole 12 to facilitate the connection between the conductive part 22 and the first pole 12.

[0200] In some optional embodiments of the present application, in combination with Figures 6 to 8, each of the multiple poles on the shell assembly 1 is a first pole 12 having a receiving portion 121. At this time, more conductive portions 22 can be accommodated in all the first poles 12 to better improve the volume energy density of the battery cell 10.

[0201] In some other optional embodiments of the present application, in combination with Figures 9 and 10, at least one of the multiple poles on the shell assembly 1 is a first pole 12 having an accommodating portion 121 and at least one is a second pole 15 without an accommodating portion 121, so that the first pole 12 and the second pole 15 can be flexibly selected and matched according to actual requirements such as energy density and cost to improve the applicability of the battery cell 10.

[0202] In some optional embodiments, referring to Figures 9 and 10 , a relief groove 18 is defined between the second pole 15 and the housing 11, and at least a portion of the conductive portion 22 is received in the relief groove 18. This can also reduce the space occupied by the conductive portion 22 within the housing 11 to a certain extent, thereby improving energy density and alleviating problems such as short circuits caused by redundant conductive portions 22.

[0203] To simplify the description, the following mainly describes an example in which all the poles on the housing 11 are first poles 12 formed with an accommodating portion 121. In addition, by way of example, in some embodiments of the present application, the housing assembly 1 may be provided with only one pole, namely the first pole 12. The first pole 12 includes two insulating parts, one serving as a positive pole and the other as a negative pole.

[0204] In the embodiment of the present application, the accommodating portion 121 can be located on the side of the first pole 12 facing the active material coating portion 21, or on the side of the first pole 12 facing away from the active material coating portion 21. For example, in conjunction with Figures 11 and 12, when the accommodating portion 121 is located on the side of the first pole 12 facing the active material coating portion 21, the accommodating portion 121 has a first accommodating groove 12110, and the surface of the first pole 12 facing the active material coating portion 21 is the pole inner end surface 122. The notch of the first accommodating groove 12110 is formed on the pole inner end surface 122, and at least a portion of the conductive portion 22 is accommodated in the first accommodating groove 12110.

[0205] Exemplarily, the first receiving groove 12110 can be a groove body, which is a groove-like structure with a certain depth. For example, when the first pole 12 is disposed on the upper end wall of the housing 11 and the pole inner end surface 122 is the lower surface of the first pole 12, the first receiving groove 12110 is formed as a receiving groove with a groove opening open downward and the groove wall recessed upward. For another example, when the first pole 12 is disposed on the lower end wall of the housing 11 and the pole inner end surface 122 is the upper surface of the first pole 12, the first receiving groove 12110 is formed as a receiving groove with a groove opening open upward and the groove wall recessed downward.

[0206] In the above technical solution, on the one hand, the first receiving groove 12110 provided on the first terminal 12 can reduce the weight of the first terminal 12 to a certain extent, thereby increasing the weight energy density of the battery cell 10 and the battery 100. On the other hand, because the notch of the first receiving groove 12110 is formed on the terminal inner end surface 122, which is the surface of the first terminal 12 on the side close to the active material coating portion 21, the first receiving groove 12110 can be opened toward the active material coating portion 21, thereby facilitating the insertion of the conductive portion 22 into the first receiving groove 12110 and improving assembly efficiency. Furthermore, this type of first receiving groove 12110 is easier to process, improving production efficiency.

[0207] In addition, the first receiving groove 12110 is easy to be processed into a larger volume, so that it can accommodate more conductive parts 22; at the same time, since the first receiving groove 12110 is open toward the active material coating part 21, the first receiving groove 12110 can also serve as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the shell 11. Since the battery cell 10 will lose electrolyte during the charging and discharging process, when there is more electrolyte, the service life of the battery cell 10 can be extended; and also because the first receiving groove 12110 is open toward the active material coating part 21, the first receiving groove 12110 can also serve as a storage and buffer structure for gas production inside the battery cell assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

[0208] In addition, since the first receiving groove 12110 is located on the inner side of the first pole 12, external foreign matter and impurities are not easy to enter the first receiving groove 12110, thereby reducing the impact of external foreign matter and impurities on the battery cell assembly 2, improving the stability and reliability of the battery cell assembly 2, and further improving the stability and reliability of the battery cell 10 and the battery 100; the first receiving groove 12110 is located on the inner side of the first pole 12, and at least part of the conductive part 22 is accommodated in the first receiving groove 12110, so as to facilitate the limiting of the conductive part 22 from the inner side of the first pole 12, and facilitate the connection of the conductive part 22 with the first pole 12.

[0209] 11 , in the embodiment of the present application, the connection method between the first pole 12 and the housing 11 is not limited, and can be, for example, welding or riveting. For example, when the two are riveted, the housing 11 has a mounting hole 113, and the first pole 12 is riveted to the mounting hole 113. Of course, it is understood that when the two are welded or otherwise coupled, the housing 11 may also have a mounting hole 113, and the first pole 12 may be mounted to the mounting hole 113. It should be noted that the mounting hole 113 may be specifically provided on the housing 111.

[0210] Optionally, in combination with Figure 11, the first accommodating groove 12110 can be set corresponding to the position of the mounting hole 113, or in other words, on the projection plane perpendicular to the axial direction R of the first pole 12, the orthographic projection of the first accommodating groove 12110 is located within the orthographic projection range of the mounting hole 113, so that the first accommodating groove 12110 can have a larger depth to accommodate more conductive parts 22, thereby reducing the space occupied by the conductive parts 22 in the shell 11 to a greater extent.

[0211] In some embodiments, with reference to FIG11 , when a mounting hole 113 is provided on the housing 11 and the first pole 12 is mounted in the mounting hole 113 , along the axial direction R of the first pole 12 , a depth H1 of the first accommodating groove 12110 is greater than or equal to a minimum distance H2 from the inner end face 122 of the pole to the mounting hole 113 .

[0212] It should be noted that the specific shape of the first receiving groove 12110 is not limited and can be regular or irregular, such as a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a hemispherical groove with an elliptical cross-section and gradually changing cross-sectional dimensions, etc. Therefore, the depth H1 of the first receiving groove 12110 refers to the maximum depth of the first receiving groove 12110 along the axial direction R of the first pole 12.

[0213] Since in the axial direction R of the first pole 12, the depth H1 of the first accommodating groove 12110 is greater than or equal to the minimum distance H2 from the inner end face 122 of the pole to the mounting hole 113, the volume of the first pole 12 can be fully utilized, so that the first accommodating groove 12110 has a larger depth, which is conducive to accommodating more conductive parts 22, and thus can greatly reduce the space occupied by the conductive parts 22 in the shell 11, further improve the energy density of the battery cell 10, and further reduce the redundancy of the conductive parts 22 in the shell 11; at the same time, since the first accommodating groove 12110 has a larger depth, it can also accommodate the gas production of the battery cell assembly 2, ensure the reliability and stability of the battery cell 10, and can also accommodate more electrolyte to ensure the service life of the battery cell 10.

[0214] It should be noted that the volume of the first receiving groove 12110 is not limited. For example, in some specific examples, the volume of the first receiving groove 12110 that can be used to accommodate the conductive portion 22 (referred to as the first volume V1) can be greater than or equal to 298 mm. 3 , so that the first receiving groove 12110 can have sufficient space to accommodate the conductive part 22 and facilitate welding of the conductive part 22 and the first pole 12. When the first volume V1 of the first receiving groove 12110 is less than 298mm 3 When the conductive portion 22 is not contained in the first receiving groove 12110 , the capacity of the conductive portion 22 to be contained in the first receiving groove 12110 is relatively weakened, and the difficulty of welding the conductive portion 22 and the first pole 12 is increased.

[0215] It is worth noting that the first volume V1 of the first receiving groove 12110 is the difference between the total volume V2 of the first receiving groove 12110 and the volume of the first receiving groove 12110 required to accommodate other components except the conductive part 22 (recorded as the second volume V3), that is, V1 = V2 - V3. It is understandable that when the first receiving groove 12110 does not need to accommodate other components except the conductive part 22, the second volume V3 can be 0mm. 3 For example, the first volume V1 of the first receiving tank 12110 can be 300 mm 3 -1500mm 3 , for example, 300mm 3 , 400mm 3 , 500mm 3 , 600mm 3 , 700mm 3 , 800mm 3 , 1000mm 3 , 1200mm 3 , 1400mm 3 , 1500mm 3 etc.

[0216] In conjunction with Figures 11 and 12, in order to ensure the stability and reliability of the electrical connection between the active material coating portion 21 and the first electrode 12, in some embodiments of the present application, the electrical connection position between the conductive portion 22 and the first electrode 12 can be located on the groove wall of the first receiving groove 12110. For example, the conductive portion 22 and the first electrode 12 can be electrically connected by welding, and the electrical connection position is the welding position of the conductive portion 22 and the first electrode 12. At the same time, the welding method of the conductive portion 22 and the first electrode 12 is not limited, for example, it can be laser welding, and depending on factors such as the position, angle, or structure of the welding part, vertical welding, inclined welding, lap welding, or edge sealing welding can be selected. In other embodiments of the present application, the conductive portion 22 and the first electrode 12 can also be electrically connected by other methods instead of welding, such as by providing conductive glue or conductive nails. To simplify the description, the following description uses the example of the conductive portion 22 and the first electrode 12 being electrically connected by welding, and the welding position is the electrical connection position of the conductive portion 22 and the first electrode 12.

[0217] 11 and 12 , more specifically, the first electrode 12 includes a first end wall 12111 and a first side wall 12113. The first end wall 12111 is located on a side of the first side wall 12113 away from the active material coating portion 21. The first end wall 12111 and the first side wall 12113 enclose a first receiving groove 12110. The electrical connection between the conductive portion 22 and the first electrode 12 is located on the first end wall 12111 and / or the first side wall 12113. In other words, the conductive portion 22 may be welded to at least one of the first end wall 12111 and the first side wall 12113.

[0218] In the above technical solution, by locating the electrical connection point between the conductive portion 22 and the first terminal 12 on at least one of the first end wall 12111 and the first side wall 12113, the first receiving groove 12110 not only accommodates at least a portion of the conductive portion 22, but also the groove wall of the first receiving groove 12110 functions to electrically connect with the conductive portion 22. This simplifies the structure of the first terminal 12, facilitating its processing, and further simplifies the structure of the conductive portion 22, reducing redundancy and cost. Furthermore, by utilizing the groove wall of the first receiving groove 12110 to achieve electrical connection with the conductive portion 22, a relatively large area for electrical connection between the conductive portion 22 and the first terminal 12 can be provided, which not only reduces the difficulty of electrical connection but also improves the reliability and stability of the electrical connection, thereby enhancing the performance of the battery cell 10. When the electrical connection point between the conductive portion 22 and the first terminal 12 is located on the first end wall 12111, external connection between the conductive portion 22 and the first end wall 12111 is facilitated.

[0219] In addition, since the electrical connection position between the conductive part 22 and the first pole 12 is located in the first receiving groove 12110, it can not only prevent the electrical connection position from protruding from the outside of the first pole 12 and occupying the space outside the first pole 12, but also enable the electrical connection position to be protected by the first pole 12, thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole 12.

[0220] In addition, in an embodiment of the present application, the first end wall 12111 is constructed as a closed structure without any perforations, so that the first receiving tank 12110 is isolated from the external space of the shell 11, thereby avoiding the problem of the electrolyte in the shell 11 leaking from the first receiving tank 12110.

[0221] In conjunction with Figures 11 and 12 , in some optional embodiments, the shape of a portion of the conductive portion 22 matches the shape of a portion of the first end wall 12111, and the conductive portion 22 is positioned in a manner that conforms to the shape of the first end wall 12111 and is electrically connected thereto, such that the portion where the conductive portion 22 is electrically connected to the first end wall 12111 extends along the length or width of the first end wall 12111. For example, when the first end wall 12111 is planar, a portion of the conductive portion 22 can also be planar and conform to the first end wall 12111, and an electrical connection, such as welding, can be made at the conforming portion. This can increase the area of ​​the electrical connection, improving the reliability and stability of the electrical connection.

[0222] In addition, when the electrical connection between the conductive part 22 and the first end wall 12111 is welding, since the first end wall 12111 is located on the side of the first receiving groove 12110 away from the active material coating part 21, the welding operation is facilitated. For example, welding can be performed from the side of the first pole 12 away from the active material coating part 21.

[0223] It is worth noting that the shape of the first end wall 12111 is not limited, and can be, for example, a flat plate, an arc-shaped plate, etc. Specifically, when the first end wall 12111 is a flat plate structure, the first end wall 12111 is arranged at an angle to the axial direction R of the first pole 12. For example, the first end wall 12111 can be a flat plate structure perpendicular to the axial direction R of the first pole 12, or can be an inclined plate structure that is not perpendicular to the axial direction R of the first pole 12, but the inclination direction is not limited.

[0224] Of course, in other embodiments of the present application, the position where the conductive part 22 is electrically connected to the first end wall 12111 may not extend along the length or width direction of the first end wall 12111. For example, it may be a plurality of discretely arranged points. For example, the conductive part 22 has a plurality of spaced-apart parts that are respectively welded to the first end wall 12111, which will not be elaborated here.

[0225] With reference to FIG13 , in some embodiments of the present application, when the conductive portion 22 is electrically connected to the first end wall 12111, a first sinking groove 12112 may be provided on the first end wall 12111, with the first sinking groove 12112 extending downward away from the active material coating portion 21. At least a portion of the location where the conductive portion 22 is electrically connected to the first end wall 12111 is located within the first sinking groove 12112. For example, at least a portion of the conductive portion 22 may be disposed within the first sinking groove 12112 and connected to the portion of the first end wall 12111 defining the first sinking groove 12112.

[0226] In the above technical solution, on the one hand, the first sink groove 12112 can be used to realize pre-positioning and limiting of the electrical connection position of the conductive part 22, which is not only conducive to finding the correct position to realize electrical connection and improve production efficiency, but also helps to improve the stability and reliability of the conductive part 22, and ensure the stability and reliability of the battery cell 10 during the charging and discharging process; on the other hand, by arranging the first sink groove 12112 on the first end wall 12111, the local wall thickness of the first end wall 12111 can be locally thinned, which is not only conducive to welding, but also helps to reduce the weight of the first pole 12 and improve the weight energy density of the battery cell 10.

[0227] In some optional embodiments, a portion of the conductive portion 22 matches the shape of the first side wall 12113 and is disposed in close contact with it. For example, when the first side wall 12113 is curved, a portion of the conductive portion 22 may also be curved and in close contact with the first side wall 12113. The in close contact portion is then electrically connected (e.g., by welding) so that the portion where the conductive portion 22 is electrically connected to the first side wall 12113 extends along the first side wall 12113. This increases the area of ​​the electrical connection, thereby improving the reliability and stability of the electrical connection.

[0228] Of course, the present application is not limited to this. In other embodiments of the present application, the position where the conductive part 22 is electrically connected to the first side wall 12113 may not extend along the first side wall 12113. For example, it may be a plurality of discretely arranged points. For example, the conductive part 22 has a plurality of spaced-apart parts that are respectively welded to the first side wall 12113, which will not be elaborated here.

[0229] It should be noted that the number of first side walls 12113 is not limited and can be determined based on the shape of the first receiving groove 12110, as long as the end of each first side wall 12113 away from the notch of the first receiving groove 12110 is connected to the first end wall 12111. By way of example, when the cross-sectional shape of the first receiving groove 12110 is circular or elliptical, the first end wall 12111 is circular or elliptical, and there is one first side wall 12113 in an annular shape, disposed around the circumferential edge of the first end wall 12111. By way of further example, when the cross-sectional shape of the first receiving groove 12110 is rectangular or oblong, the first end wall 12111 is rectangular or oblong, and there are four first side walls 12113, each connected to the four sides of the first end wall 12111.

[0230] It should also be noted that the first receiving groove 12110 is not limited to the form defined by the first end wall 12111 and the first side wall 12113. For example, in some embodiments, the first end wall 12111 may not exist. In this case, the end of the notch of each first side wall 12113 away from the first receiving groove 12110 converges together, so that the first receiving groove 12110 is defined only by multiple first side walls 12113. At this time, the conductive part 22 can be electrically connected to the first side wall 12113 to ensure that the charging and discharging process of the battery cell 10 proceeds normally.

[0231] In addition, it is worth noting that in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the first pole 12 may not be located in the first receiving groove 12110. For example, the electrical connection position between the conductive portion 22 and the first pole 12 may also be located on the inner end surface 122 of the pole.

[0232] In combination with Figures 12 and 13, in an embodiment of the present application, the first pole 12 can also be provided with a first groove 126 as required. The first groove 126 is located on the side of the first pole 12 away from the active material coating portion 21, that is, the surface of the side of the first pole 12 away from the active material coating portion 21 is the pole outer end face 123, and the notch of the first groove 126 is formed on the pole outer end face 123.

[0233] It is understood that the first groove 126 is a groove body, which is a groove-like structure with a certain depth. Furthermore, when the first pole 12 is disposed on the upper end wall of the housing 11 and the pole outer end surface 123 is the upper surface of the first pole 12, the first groove 126 is formed as a groove with an upwardly open groove opening and a downwardly recessed groove wall. For another example, when the first pole 12 is disposed on the lower end wall of the housing 11 and the pole outer end surface 123 is the lower surface of the first pole 12, the first groove 126 is formed as a groove with a downwardly open groove opening and an upwardly recessed groove wall.

[0234] In the above technical solution, on the one hand, since the first pole 12 is provided with the first groove 126, the weight of the first pole 12 can be further reduced, so as to improve the weight energy density of the battery cell 10 and the battery 100; on the other hand, the first groove 126 is located on the outside of the first pole 12, that is, it is open to the side of the first pole 12 away from the interior of the shell 11. The first groove 126 can be used to accommodate or install structural components in the battery 100 that electrically connect the various battery cells 10, so as to make full use of the space inside the first pole 12 and improve the space utilization and volume energy density of the battery 100.

[0235] In addition, since the first electrode 12 has both the first receiving groove 12110 and the first groove 126, the first groove 126 is located on the side of the first receiving groove 12110 away from the active material coating portion 21, and the first groove 126 is open in a direction away from the first receiving groove 12110. This facilitates laser welding of the conductive portion 22 to the first end wall 12111 through the first groove 126 from the outside of the first electrode 12, i.e., the side of the first electrode 12 away from the active material coating portion 21, thereby facilitating electrical connection between the conductive portion 22 and the first electrode 12 through external welding. In other words, the above-mentioned structural arrangement facilitates external welding of the first electrode 12 and the conductive portion 22 through the first groove 126, facilitates the processing and manufacturing of the battery cell 10, and can save processing and manufacturing costs.

[0236] Furthermore, in order to conveniently and effectively weld the conductive part 22 to the groove wall of the first receiving groove 12110 through the first groove 126, and improve the welding reliability of the groove wall of the conductive part 22 to the first receiving groove 12110, in an embodiment of the present application, the part between the first groove 126 and the first receiving groove 12110 can be laser welded to the conductive part 22, that is, the spacer part 127 shown in Figure 13 is laser welded to the conductive part 22. The thickness of the spacer 127 of the first pole 12 located between the first groove 126 and the first receiving groove 12110 is relatively thin. The spacer 127 isolates the first groove 126 and the first receiving groove 12110. The side wall of the spacer 127 close to the active material coating part 21 can be used as the first end wall 12111. When the conductive part 22 needs to be welded to the first end wall 12111, since the thickness of the spacer 127 is relatively thin, it is conducive to welding the conductive part 22 and the first end wall 12111 through the first groove 126, thereby improving the convenience and reliability of welding.

[0237] In some embodiments, the first receiving groove 12110 can be configured in a cross-sectional shape with a length greater than its width, such as a rectangle, an ellipse, an oblong, or the like. The weld mark formed by welding the conductive portion 22 to the first electrode 12 can be a long, strip-shaped weld mark parallel to the length of the first receiving groove 12110, thereby improving welding reliability and enhancing current flow performance. For example, when the weld mark formed by welding the conductive portion 22 to the first end wall 12111 is a long, strip-shaped weld mark, the width of the weld mark can be greater than or equal to 6 mm, and the distance between the weld mark and the first side wall 12113 can be greater than or equal to 1 mm, thereby ensuring welding convenience and reliability while also ensuring the current flow capacity of the battery cell 10.

[0238] 12 , the housing assembly 1 may further include a slot cover 7 , which is provided on the first pole 12 and covers the slot opening of the first groove 126 .

[0239] In the above technical solution, by providing a slot cover 7 that covers the first groove 126, the first pole 12 can be indirectly electrically connected to the busbar through the slot cover 7. By adjusting the position and structure of the slot cover 7, the electrical connection between the slot cover 7 and the busbar is more convenient and the electrical connection area is larger. Therefore, the provision of the slot cover 7 facilitates the electrical connection between adjacent battery cells 10 in the battery 100. Since the location where the battery cells 10 are electrically connected is located on the slot cover 7, the electrical connection location between the conductive portion 22 and the first pole 12 can be separated by the first groove 126, reducing interference between the two, and further improving the stability and reliability of the battery cells 10.

[0240] It should be noted that the specific structure of the battery cell assembly 2 of the embodiment of the present application is not limited, for example, it may include but is not limited to the following two implementation methods.

[0241] 13-14 , in a first embodiment, the active material coating portion 21 includes a current collector 211 and an active material layer 212 disposed on the current collector 211. The conductive portion 22 includes a tab portion 221 electrically connected to the current collector 211. The tab portion 221 includes a plurality of tab pieces 2211. The tab pieces 2211 are electrically connected to the current collector 211 but are not coated with active material. They can be formed by directly die-cutting the current collector 211. The plurality of tab pieces 2211 converge near the current collector 211 (i.e., converge toward each other) to form a first gathered portion 2212. The plurality of tab pieces 2211 converge and connect to form a second gathered portion 2213 away from the current collector 211. The first gathered portion 2212 connects the second gathered portion 2213 and the active material coating portion 21. When the receiving portion 121 includes a first receiving groove 12110, at least a portion of the second gathered portion 2213 can be received within the first receiving groove 12110.

[0242] In the above technical solution, the plurality of tabs 2211 are merely brought together (i.e., gathered in a direction approaching each other) but not connected when forming the first gathered portion 2212, whereas the plurality of tabs 2211 are not only brought together but also connected into an integrated structure when forming the second gathered portion 2213. For example, the plurality of tabs 2211 may be connected into an integrated plate structure by welding (e.g., ultrasonic welding) to form the second gathered portion 2213, but the present application is not limited thereto. For example, the plurality of tabs 2211 may also be brought together and connected to form the second gathered portion 2213 by bonding with conductive adhesive, etc., which will not be described in detail here.

[0243] It should be noted that in the embodiments of the present application, the tabs 2211 are divided into positive electrode tabs 2211 and negative electrode tabs 2211. The positive electrode tabs 2211 that need to be gathered together are stacked together and ultrasonically pre-welded to form the positive electrode second gathered portion 2213. This can reduce the gaps between layers, allowing the fluffy multiple positive electrode tabs 2211 to form a sheet structure with a certain degree of rigidity. Similarly, the negative electrode tabs 2211 that need to be gathered together are stacked together and ultrasonically pre-welded to form the negative electrode second gathered portion 2213. This can reduce the gaps between layers, allowing the fluffy multiple negative electrode tabs 2211 to form a sheet structure with a certain degree of rigidity.

[0244] In the above technical solution, the phrase "a plurality of electrode tabs 2211 converge at positions close to the current collector 211 to form a first gathered portion 2212, and a plurality of electrode tabs 2211 converge and connect at positions away from the current collector 211 to form a second gathered portion 2213" is intended to explain that, along the extension direction of the electrode tab 2211, the first gathered portion 2212 and the second gathered portion 2213 are sequentially arranged in a direction away from the current collector 211, and the specific positions of the first gathered portion 2212 and the second gathered portion 2213 are not limited, i.e., there is no requirement for the first gathered portion 2212 to be close to the current collector 211, nor for the second gathered portion 2213 to be far from the current collector 211. In some optional examples, the current collector 211 and the electrode tab 2211 may be an integral part, such as an integrally formed aluminum foil for a positive electrode tab, or an integrally formed copper foil for a negative electrode tab, and so on.

[0245] In the above technical solution, since the pole ear portion 221 includes a second gathered portion 2213 formed by converging and connecting multiple pole ear sheets 2211, at least a portion of the second gathered portion 2213 is accommodated in the first accommodating groove 12110, which facilitates the connection between the conductive portion 22 and the first pole 12, can fully utilize the space of the first pole 12, and improve the volume energy density of the battery cell 10.

[0246] 12-14 , in the first embodiment, at least a portion of the first gathered portion 2212 is accommodated within the first receiving groove 12110. In the above technical solution, at least a portion of the first gathered portion 2212 and at least a portion of the second gathered portion 2213 of the electrode lug 221 are both accommodated within the first receiving groove 12110, thereby more fully utilizing the space within the first electrode 12 and further reducing the space occupied by the electrode lug 221 within the housing 11 to accommodate a larger active material coating portion 21, thereby improving the volumetric energy density of the battery cell 10. Furthermore, the redundancy of the electrode lug 221 within the housing 11 can be further reduced, further reducing the probability of short circuit between the electrode lug 221 and the active material coating portion 21.

[0247] In this embodiment, the second gathered portion 2213 is directly or indirectly electrically connected to the first terminal 12. For example, referring to Figure 12 , when the second gathered portion 2213 is directly electrically connected to the first terminal 12, such as when the second gathered portion 2213 is welded (e.g., laser welded) to the first terminal 12, the structure of the battery cell assembly 2 can be simplified, reducing parts, simplifying the assembly process, and improving assembly efficiency. The method and location of the direct electrical connection between the second gathered portion 2213 and the first terminal 12 are not limited. For example, the electrical connection position between the second gathering portion 2213 and the first pole 12 can be located at the first end wall 12111 and / or the first side wall 12113. Furthermore, the electrical connection position between the second gathering portion 2213 and the first end wall 12111 can extend along the length direction or width direction of the first end wall 12111. Further, the first end wall 12111 has a first groove 12112, and the electrical connection position between the second gathering portion 2213 and the first end wall 12111 can be located in the first groove 12112, and so on. The corresponding technical effects can be referred to the introduction of the above embodiments and will not be repeated here.

[0248] As an optional solution, the conductive portion 22 may also be provided with a transition piece 222 as required, in which case the second retracted portion 2213 is indirectly electrically connected to the first pole 12. Specifically, with reference to FIG13 , when the conductive portion 22 includes the transition piece 222, the transition piece 222 is connected to the second retracted portion 2213, and the conductive portion 22 is electrically connected to the first pole 12 via the transition piece 222. In this case, at least a portion of the transition piece 222 is accommodated within the first receiving groove 12110. In this example, at least a portion of the second retracted portion 2213 is also accommodated within the first receiving groove 12110. However, the first retracted portion 2212 may or may not be accommodated within the first receiving groove 12110.

[0249] In the above technical solution, the active material coating portion 21 can be electrically connected to the first electrode 12 through the first gathered portion 2212, the second gathered portion 2213, and the adapter plate 222 in sequence. The location where the conductive portion 22 is electrically connected to the first electrode 12 is located on the adapter plate 222. For example, the electrical connection can be achieved by welding (e.g., laser welding) the adapter plate 222 to the first electrode 12. In addition, the adapter plate 222 and the tab 2211 are two separate components and are connected by welding (e.g., ultrasonic welding).

[0250] In the above technical solution, on the one hand, by accommodating at least a portion of the second accordion portion 2213 and at least a portion of the adapter plate 222 within the first receiving groove 12110, the space within the first electrode 12 can be more fully utilized, further reducing the space occupied by the conductive portion 22 within the housing 11, thereby improving the volumetric energy density of the battery cell 10. Furthermore, when at least a portion of the first accordion portion 2212, at least a portion of the second accordion portion 2213, and at least a portion of the adapter plate 222 are all accommodated within the first receiving groove 12110, the space within the first electrode 12 can be further fully utilized, more effectively reducing the space occupied by the conductive portion 22 within the housing 11, thereby further improving the volumetric energy density of the battery cell 10.

[0251] On the other hand, by using the adapter plate 222 to achieve indirect electrical connection between the second gathered portion 2213 and the first pole 12, the adapter plate 222 can be welded to the first pole 12 at a position avoiding the second gathered portion 2213, so that the welding between the adapter plate 222 and the first pole 12 is firm, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, by electrically connecting the first pole 12 and the pole tab 2211 through the adapter plate 222, the structure of the pole tab 2211 can also be simplified.

[0252] Among them, the direct electrical connection method and position of the adapter plate 222 and the first pole 12 are not limited. For example, the adapter plate 222 is electrically connected to the first pole 12 by welding. For example, the electrical connection position of the adapter plate 222 and the first pole 12 can be located at the first end wall 12111 and / or the first side wall 12113. Further, the position where the adapter plate 222 is electrically connected to the first end wall 12111 can extend along the length direction or width direction of the first end wall 12111. Further, the first end wall 12111 has a first sink 12112, and the position where the adapter plate 222 is electrically connected to the first end wall 12111 can be located in the first sink 12112, etc. The corresponding technical effects can be referred to the introduction of the above embodiment and will not be repeated here. When the electrical connection position between the adapter plate 222 and the first pole 12 is located at the first end wall 12111 and / or the first side wall 12113, since at least part of the adapter plate 222 is accommodated in the first accommodating groove 12110, the structure of the adapter plate 222 can be simplified, redundancy can be reduced, and cost can be lowered.

[0253] 13-14 , in a second embodiment, the active material coating portion 21 includes a current collector 211 and an active material layer 212 disposed on the current collector 211. The conductive portion 22 includes a tab portion 221 and a transition piece 222. The tab portion 221 includes a plurality of tabs 2211 electrically connected to the current collector 211. The plurality of tabs 2211 converge near the current collector 211 to form a first gathered portion 2212. The plurality of tabs 2211 converge and connect to form a second gathered portion 2213 away from the current collector 211. The transition piece 222 is electrically connected to the second gathered portion 2213. When the accommodating portion 121 has a first accommodating groove 12110, at least a portion of the transition piece 222 can be accommodated in the first accommodating groove 12110 and electrically connected to the first electrode 12.

[0254] In the above technical solution, compared with the solution in the first embodiment including the adapter plate 222, in the second embodiment, at least a portion of the adapter plate 222 is accommodated in the first accommodating groove 12110, but the relative position of the pole ear portion 221 and the first accommodating groove 12110 is not limited, that is, at least a portion of the pole ear portion 221 can be accommodated in the first accommodating groove 12110, and the pole ear portion 221 can also be completely located outside the first accommodating groove 12110, thereby meeting different structural design requirements.

[0255] In the above technical solution, by accommodating at least a portion of the adapter plate 222 in the first accommodating groove 12110, the adapter plate 222 can occupy the space in the first pole 12, thereby reducing the space occupied by the adapter plate 222 in the shell 11 to accommodate a larger active material coating part 21, thereby improving the volume energy density of the battery cell 10, and reducing the probability of short circuit between the adapter plate 222 and the active material coating part 21, reducing the risk of short circuit of the battery cell assembly 2, and thus improving the stability and reliability of the battery cell 10.

[0256] In addition, by using the adapter plate 222 to achieve indirect electrical connection between the second retracted portion 2213 and the first pole 12, the adapter plate 222 can be welded to the first pole 12 at a position avoiding the second retracted portion 2213, so that the welding between the adapter plate 222 and the first pole 12 is firm, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, by electrically connecting the first pole 12 and the pole tab 2211 through the adapter plate 222, the structure of the pole tab 2211 can also be simplified.

[0257] For example, in some optional embodiments, such as the first embodiment above or the third embodiment below, when the second gathered portion 2213 is directly electrically connected to the first electrode 12, the conductive portion 22 may be composed solely of the positive electrode tab and the negative electrode tab in each electrode assembly 2a. For example, in other embodiments, such as the first or second embodiment above, or the third or fourth embodiment below, when the second gathered portion 2213 is indirectly electrically connected to the first electrode 12 via the adapter 222, the conductive portion 22 may be composed simultaneously of the positive electrode tab and the negative electrode tab in each electrode assembly 2a and each adapter 222.

[0258] In some embodiments, when the battery cell assembly 2 includes two electrode assemblies 2a, the tabs 2211 of the two electrode assemblies 2a can be folded together, and the folding position is located at the center between the two electrode assemblies 2a to form a symmetrical folded form (for example, as shown in Figures 14 and 15(a)). Alternatively, in some other embodiments, when the tabs 2211 of the two electrode assemblies 2a are folded together, the folding position can also be biased towards one of the electrode assemblies 2a to form an asymmetrical folded form (for example, as shown in Figures 15(b) and 15(c)). In addition, the electrode assembly 2a can be in a full-tab form (for example, as shown in Figure 15(a)) or a half-tab form (for example, as shown in Figures 14, 15(b) and 15(c)).

[0259] Of course, the present application is not limited to this, and the tabs 2211 of the same polarity of the two electrode assemblies 2a may not be folded together. For example, the tabs 2211 of each electrode assembly 2a may be folded separately according to the positive and negative poles, that is, the positive tab of one electrode assembly 2a is folded separately, and the positive tab of the other electrode assembly 2a is also folded separately. This is not detailed here.

[0260] It should be noted that the accommodating portion 121 of the embodiment of the present application is not limited to having the form of the first accommodating groove 12110. For example, some other optional embodiments will be given later.

[0261] For example, in combination with Figure 16, in some embodiments of the present application, the accommodating portion 121 can also be configured to include a second accommodating groove 12120, the surface of the first pole 12 away from the active material coating portion 21 is the pole outer end face 123, the notch of the second accommodating groove 12120 is formed on the pole outer end face 123, the second accommodating groove 12120 is connected to the interior of the shell 11 through the first through-hole 12130, the conductive portion 22 is passed through the first through-hole 12130 and is at least partially accommodated in the second accommodating groove 12120.

[0262] It is understood that the second receiving groove 12120 is a groove body, which is a groove-like structure with a certain depth. For example, when the first pole 12 is disposed on the upper end wall of the housing 11 and the pole outer end surface 123 is the upper surface of the first pole 12, the second receiving groove 12120 is formed as a receiving groove with an upwardly open groove opening and a downwardly recessed groove wall. For another example, when the first pole 12 is disposed on the lower end wall of the housing 11 and the pole outer end surface 123 is the lower surface of the first pole 12, the second receiving groove 12120 is formed as a receiving groove with a downwardly open groove opening and an upwardly recessed groove wall.

[0263] In the above technical solution, combined with Figure 16, on the one hand, the first electrode 12 is provided with a second receiving groove 12120, which can reduce the weight of the first electrode 12 to a certain extent, so as to improve the weight energy density of the battery cell 10 and the battery 100; on the other hand, since the notch of the second receiving groove 12120 is formed on the electrode outer end surface 123, and the electrode outer end surface 123 is the surface of the first electrode 12 away from the active material coating portion 21, the second receiving groove 12120 can be open in the direction away from the active material coating portion 21. In this way, when at least a portion of the conductive portion 22 is accommodated in the second receiving groove 12120, the conductive portion 22 can be easily stored and sorted through the notch of the second receiving groove 12120, and the electrical connection operation between the conductive portion 22 and the first electrode 12 can be easily achieved through the notch of the second receiving groove 12120, thereby reducing the production difficulty of the battery cell 10 and improving the production efficiency of the battery cell 10.

[0264] At the same time, since the second receiving tank 12120 can be connected to the interior of the shell 11 through the first perforation 12130, the second receiving tank 12120 can also serve as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the shell 11. Since the battery cell 10 will lose electrolyte during the charging and discharging process, when there is more electrolyte, the service life of the battery cell 10 can be extended; and because the second receiving tank 12120 can be connected to the interior of the shell 11 through the first perforation 12130, the second receiving tank 12120 can also serve as a receiving and buffer structure for gas production inside the battery cell assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

[0265] It is worth noting that when the receiving portion 121 has the second receiving groove 12120 and the conductive portion 22 is passed through the first through hole 12130 and is at least partially received in the second receiving groove 12120 , the electrical connection position between the conductive portion 22 and the first pole 12 is not limited.

[0266] Exemplarily, when the conductive portion 22 is passed through the first through-hole 12130 and is at least partially accommodated in the second accommodating groove 12120 , in some embodiments of the present application, the electrical connection position between the conductive portion 22 and the first pole 12 is located on the hole wall of the first through-hole 12130 formed by the first pole 12 .

[0267] In the above technical solution, the electrical connection position between the conductive part 22 and the first pole 12 is set on the hole wall of the first through-hole 12130, thereby facilitating the electrical connection operation between the conductive part 22 and the first pole 12 through the second receiving groove 12120. Moreover, when the electrical connection area between the conductive part 22 and the first pole 12 is large, the electrical connection between the conductive part 22 and the first pole 12 can be utilized to achieve the sealing of the first through-hole 12130, thereby saving sealing costs, reducing electrolyte leakage, and saving sealing parts.

[0268] Specifically, the conductive part 22 can be welded to the hole wall of the first through-hole 12130 at the position where the first through-hole 12130 is connected to the second receiving groove 12120, so as to facilitate the operation. Moreover, by controlling the weld mark, the weld mark and the conductive part 22 can be used to seal the first through-hole 12130 to improve the problem of the electrolyte in the shell 11 leaking from the first through-hole 12130.

[0269] As another example, when the conductive portion 22 is passed through the first through-hole 12130 and is at least partially accommodated in the second receiving groove 12120, in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the first pole 12 may also be located on the wall of the second receiving groove 12120 formed by the first pole 12. This facilitates electrical connection operations. For example, when the conductive portion 22 is welded to the wall of the second receiving groove 12120 formed by the first pole 12, the risk of conductive particles generated by the welding entering the housing 11 and causing a short circuit or other problems can be reduced.

[0270] Specifically, in combination with Figures 16 and 17, the first pole 12 includes a second end wall 12121 and a second side wall 12123, the second end wall 12121 is located on the side of the second side wall 12123 close to the active material coating portion 21, the second end wall 12121 and the second side wall 12123 are arranged to form a second accommodating groove 12120, the first through-hole 12130 is opened on the second end wall 12121, and the electrical connection position between the conductive portion 22 and the first pole 12 is located on the second end wall 12121 and / or on the second side wall 12123.

[0271] More specifically, the conductive portion 22 and the first pole 12 can be electrically connected by welding, so the welding position is the electrical connection position between the conductive portion 22 and the first pole 12. In other embodiments of the present application, the conductive portion 22 and the first pole 12 can also be electrically connected by other methods instead of welding, such as by providing conductive glue or conductive nails, which will not be described in detail here.

[0272] To simplify the description, the following description uses the example of welding the conductive portion 22 to the first pole 12 to form an electrical connection, where the welding location is the electrical connection location between the conductive portion 22 and the first pole 12. For example, in some embodiments, the electrical connection location between the conductive portion 22 and the first pole 12 is located at the second end wall 12121 and / or the second side wall 12123, and the conductive portion 22 may be welded to at least one of the second end wall 12121 and the second side wall 12123.

[0273] In the above technical solution, by disposing the electrical connection point between the conductive portion 22 and the first terminal 12 on at least one of the second end wall 12121 and the second side wall 12123, the second receiving groove 12120 not only serves to accommodate at least a portion of the conductive portion 22, but the groove wall of the second receiving groove 12120 also serves to achieve electrical connection with the conductive portion 22. This simplifies the structure of the first terminal 12 and facilitates the processing of the first terminal 12. Furthermore, since the first through-hole 12130 is provided in the second end wall 12121, the conductive portion 22 can be easily extended into the second receiving groove 12120 through the first through-hole 12130, thereby simplifying the structure of the conductive portion 22, reducing redundancy of the conductive portion 22, and reducing the cost of the conductive portion 22. Moreover, the opening direction of the slot of the second receiving groove 12120 makes it easy to electrically connect the conductive part 22 with the slot wall of the second receiving groove 12120 through the slot of the second receiving groove 12120, which can reduce the difficulty of electrical connection. Moreover, by utilizing the slot wall of the second receiving groove 12120 to achieve electrical connection with the conductive part 22, the area where the conductive part 22 is electrically connected to the first pole 12 can be relatively large, which can improve the reliability and stability of the electrical connection, thereby improving the performance of the battery cell 10.

[0274] In addition, since the electrical connection position between the conductive part 22 and the first pole 12 is located in the second receiving groove 12120, it can not only prevent the electrical connection position from protruding from the outside of the first pole 12 and occupying the space outside the first pole 12, but also enable the electrical connection position to be protected by the first pole 12, thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole 12.

[0275] In conjunction with Figures 16 and 17 , in some embodiments, the shape of a portion of the conductive portion 22 matches the shape of a portion of the second end wall 12121, and the conductive portion 22 is positioned in a manner that conforms to the shape of the second end wall 12121 and is electrically connected thereto, such that the portion where the conductive portion 22 is electrically connected to the second end wall 12121 extends along the length or width of the second end wall 12121. For example, when the second end wall 12121 is planar, a portion of the conductive portion 22 can also be planar and conform to the second end wall 12121, and an electrical connection, such as welding, can be made at the conforming portion. This can increase the area of ​​the electrical connection, improving the reliability and stability of the electrical connection.

[0276] It is worth noting that the shape of the second end wall 12121 is not limited, and can be, for example, a flat plate or an arc-shaped plate structure. When the second end wall 12121 is a flat plate structure, it is arranged at an angle to the axial direction R of the first pole 12. For example, it can be a flat plate structure perpendicular to the axial direction R of the first pole 12, or it can be an inclined flat plate structure that is not perpendicular to the axial direction R of the first pole 12, but the inclination direction is not limited.

[0277] For example, with reference to Figures 16 and 17 , when the second end wall 12121 is a flat plate, the angle θ between the second end wall 12121 and the axial direction R of the first electrode 12 is equal to 90°. That is, along the direction from the first through-hole 12130 to the second side wall 12123, the second end wall 12121 is equidistant from the active material coating portion 21. This facilitates welding of the conductive portion 22 to the second end wall 12121.

[0278] For another example, in conjunction with Figure 18, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 is greater than 90°, that is, along the direction from the first through-hole 12130 to the second side wall 12123, the second end wall 12121 extends obliquely toward the active material coating portion 21. As a result, the extension distance of the conductive portion 22 along the second end wall 12121 can be increased to increase the reliability of the electrical connection. Exemplarily, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 can be 90°-145°, such as 100°, 110°, 120°, 130°, 140°, etc., thereby making the second end wall 12121 easy to process and convenient for electrical connection with the conductive portion 22, and more fully utilizing the space within the first pole 12 to accommodate the conductive portion 22.

[0279] For another example, in conjunction with Figure 19, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 is less than 90°, that is, along the direction from the first through-hole 12130 to the second side wall 12123, the second end wall 12121 extends obliquely in a direction away from the active material coating portion 21. As a result, the extension distance of the conductive portion 22 along the second end wall 12121 can be increased to increase the reliability of the electrical connection. Exemplarily, the angle θ between the second end wall 12121 and the axial direction R of the first pole 12 can be 45°-90°, such as 50°, 60°, 70°, 80°, etc., so that on the one hand, the second end wall 12121 can be easily processed and convenient for electrical connection with the conductive portion 22, and on the other hand, the space within the first pole 12 can be more fully utilized to accommodate the conductive portion 22.

[0280] Of course, the present application is not limited to this. In other embodiments of the present application, the position where the conductive part 22 is electrically connected to the second end wall 12121 may not extend along the length or width direction of the second end wall 12121. It may also be a plurality of discretely arranged points. For example, the conductive part 22 has a plurality of spaced-apart parts that are respectively welded to the second end wall 12121, which will not be elaborated here.

[0281] Referring again to Figure 17 , regardless of the specific value of the angle θ between the second end wall 12121 and the axial direction R of the first electrode 12, in the embodiments of the present application, when the conductive portion 22 is electrically connected to the second end wall 12121, a second recess 12122 can be provided on the second end wall 12121 as needed. The second recess 12122 is a groove formed by partially sinking the second end wall 12121 toward the end proximal to the active material coating portion. The location where the conductive portion 22 is electrically connected to the second end wall 12121 is at least partially located within the second recess 12122.

[0282] In the above technical solution, the portion of the conductive part 22 located in the second groove 12122 is set to match the shape of the second groove 12122, and is fitted to achieve electrical connection, so that the second groove 12122 can be used to pre-position and limit the electrical connection position of the conductive part 22, which is conducive to finding the correct position to achieve electrical connection, improve production efficiency, and improve the stability and reliability of the electrical connection position, so as to ensure the reliability and stability of the charging and discharging operations of the battery cell 10.

[0283] It should be noted that in the embodiment of the present application, a portion of the conductive portion 22 can also be configured to match the shape of the second side wall 12123 and be fitted thereto. For example, when the second side wall 12123 is a curved surface, a portion of the conductive portion 22 can also be a curved surface and fit thereto, and the fitted portion can be electrically connected (e.g., welded) so that the portion where the conductive portion 22 is electrically connected to the second side wall 12123 extends along the second side wall 12123. This can increase the area of ​​the electrical connection, thereby improving the reliability and stability of the electrical connection.

[0284] It should also be noted that, in other embodiments of the present application, the position where the conductive part 22 is electrically connected to the second side wall 12123 may not extend along the second side wall 12123, for example, it may be a plurality of discretely arranged points. For example, the conductive part 22 has a plurality of spaced-apart parts that are respectively welded to the second side wall 12123, which will not be elaborated here.

[0285] It is understood that the number of second side walls 12123 is not limited and can be determined based on the shape of the second receiving groove 12120. However, it is sufficient that the end of each second side wall 12123 away from the notch of the second receiving groove 12120 is connected to the second end wall 12121. For example, when the cross-sectional shape of the second receiving groove 12120 is circular or elliptical, the second end wall 12121 is circular or elliptical, and there is one second side wall 12123 in an annular shape, disposed around the circumferential edge of the second end wall 12121. For another example, when the cross-sectional shape of the second receiving groove 12120 is rectangular or oblong, the second end wall 12121 is rectangular or oblong, and there are four second side walls 12123, each connected to the four sides of the second end wall 12121.

[0286] It should also be noted that the second accommodating groove 12120 is not limited to a form defined by the second end wall 12121 and the second side wall 12123. For example, in some embodiments, in combination with Figure 20, one end of the notch of each second side wall 12123 away from the second accommodating groove 12120 extends to the first perforation 12130, so that the second accommodating groove 12120 is defined only by multiple second side walls 12123. At this time, the conductive part 22 can be electrically connected to the second side wall 12123.

[0287] In some embodiments, in combination with Figure 32, the accommodating portion 121 can have a third accommodating groove 12140 and a second accommodating groove 12120 at the same time. The second accommodating groove 12120 is located on the side of the third accommodating groove 12140 away from the active material coating portion 21. The notch of the third accommodating groove 12140 is formed on the inner end face 122 of the first pole 12 on the side close to the active material coating portion 21, and the notch of the second accommodating groove 12120 is formed on the outer end face 123 of the first pole 12 on the side away from the active material coating portion 21. The third accommodating groove 12140 and the second accommodating groove 12120 are connected through the first through-hole 12130. At this time, a portion of the conductive portion 22 is located in the third accommodating groove 12140, and the conductive portion 22 is also passed through the first through-hole 12130, and the remaining portion of the conductive portion 22 is located in the second accommodating groove 12120, so that the space in the first pole 12 can be more fully utilized, reducing the space occupied by the conductive portion 22 in the shell 11.

[0288] It is worth noting that when the conductive portion 22 is connected to the second end wall 12121 or the second side wall 12123 via laser welding, referring to FIG. 20 , the angle β between the welded portion of the conductive portion 22 and the axis of the first through-hole 12130 can be set to be greater than 5°. This reduces the risk of laser light entering the housing 11 through the first through-hole 12130 and facilitates the welding operation. Furthermore, when the angle β between the welded portion of the conductive portion 22 and the axis of the first through-hole 12130 is close to 5°, edge welding can be used; the remaining welds can be lap welded.

[0289] Referring again to FIG. 16 , in the embodiment of the present application, the connection method between the first pole 12 and the housing 11 is not limited, and can be welding or riveting. For example, when the two are riveted, the housing 11 has a mounting hole 113, and the first pole 12 is riveted to the mounting hole 113. Of course, it is understood that when the two are welded or otherwise coupled, the housing 11 may also have a mounting hole 113, and the first pole 12 may be mounted to the mounting hole 113.

[0290] Optionally, in combination with Figure 16, the second accommodating groove 12120 can be set corresponding to the position of the mounting hole 113, or in other words, on the projection plane perpendicular to the axial direction R of the first pole 12, the orthographic projection of the second accommodating groove 12120 is located within the orthographic projection range of the mounting hole 113, so that the second accommodating groove 12120 can have a larger depth to accommodate more conductive parts 22, thereby reducing the space occupied by the conductive parts 22 in the shell 11 to a greater extent.

[0291] In some embodiments, in combination with Figure 16, when the housing 11 has a mounting hole 113 and the first pole 12 is installed in the mounting hole 113, along the axial direction R of the first pole 12, the depth H3 of the second accommodating groove 12120 is greater than or equal to the minimum distance H4 from the outer end surface 123 of the pole to the mounting hole 113.

[0292] It should be noted that the specific shape of the second receiving groove 12120 is not limited and can be regular or irregular, such as a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a hemispherical groove with an elliptical cross-section and gradually changing cross-sectional dimensions, etc. It is worth noting that the oblong shape described herein refers to a shape in which the two short sides of a rectangle are replaced by convex curves, such as the shape shown in Figure 22(b).

[0293] Therefore, the depth H3 of the second receiving groove 12120 refers to the maximum depth of the second receiving groove 12120 along the axial direction R of the first terminal 12. Since the depth H3 of the second receiving groove 12120 is greater than or equal to the minimum distance H4 between the terminal outer end surface 123 and the mounting hole 113 in the axial direction R of the first terminal 12, the volume of the first terminal 12 can be fully utilized, resulting in the second receiving groove 12120 having a greater depth, which is conducive to accommodating more conductive portions 22. In turn, the space occupied by the conductive portions 22 within the housing 11 can be greatly reduced, further improving the energy density of the battery cell 10 and further reducing the redundancy of the conductive portions 22 within the housing 11. At the same time, the greater depth of the second receiving groove 12120 can also accommodate gassing of the battery cell assembly 2, ensuring the reliability and stability of the battery cell 10, and can also accommodate more electrolyte to ensure the service life of the battery cell 10.

[0294] It should be noted that the volume of the second receiving groove 12120 is not limited. For example, in some specific examples, the volume of the second receiving groove 12120 that can be used to accommodate the conductive portion 22 (recorded as the third volume V4) can be greater than or equal to 298 mm. 3 , so that the second receiving groove 12120 can have sufficient space to accommodate the conductive part 22 and facilitate welding of the conductive part 22 and the first pole 12. When the third volume V4 of the second receiving groove 12120 is less than 298mm 3 When the second receiving groove 12120 has a relatively weaker capacity for the conductive portion 22, the welding difficulty of the conductive portion 22 and the first pole 12 increases. For example, the third volume V4 of the second receiving groove 12120 can be 300mm 3 , 400mm 3 , 500mm 3 , 600mm 3, 700mm 3 , 800mm 3 , 1000mm 3 etc.

[0295] It is worth noting that the third volume V4 of the second receiving tank 12120 is the difference between the total volume V5 of the second receiving tank 12120 and the volume of the second receiving tank 12120 required to accommodate other components (such as the first cover plate 13 and the second cover plate 14 described herein) other than the conductive portion 22 (recorded as the fourth volume V6), that is, V4 = V5 - V6. For example, in some specific examples, the total volume V5 of the second receiving tank 12120 can be 1400 mm 3 -1500mm 3 , so that the second receiving groove 12120 can have more sufficient space to accommodate the conductive part 22 and other components. For example, the total volume V5 of the second receiving groove 12120 can be 1420mm 3 , 1440mm 3 , 1460mm 3 、1480mm 3 、1490mm 3 etc.

[0296] In the embodiment of the present application, the shape of the first through-hole 12130 , the number of the first through-hole 12130 , and the relative positional relationship between the first through-hole 12130 and the second receiving groove 12120 are not limited.

[0297] For example, with respect to the shape of the first through-hole 12130, in conjunction with Figures 21 and 22, in an embodiment of the present application, the first through-hole 12130 can be in the form of an elongated strip to match the sheet-shaped portion of the conductive portion 22, thereby facilitating the passage of the sheet-shaped portion of the conductive portion 22. Furthermore, when the first through-hole 12130 is in the form of an elongated strip, the second receiving groove 12120 can also be configured in a shape where the cross-section is longer than the width, such as a rectangle, an ellipse, an oblong, or the like. In this case, the length direction of the first through-hole 12130 can be set to coincide with the length direction of the cross-section of the second receiving groove 12120, thereby fully utilizing the space. Furthermore, the weld mark formed by welding the conductive portion 22 to the first electrode 12 can be in the form of an elongated strip parallel to the length direction of the first through-hole 12130, thereby improving welding reliability and enhancing overcurrent performance. Exemplarily, when the conductive part 22 is welded to the second end wall 12121 to form a long strip-shaped weld mark, the width of the weld mark can be greater than or equal to 6 mm, and the distance between the weld mark and the second side wall 12123 can be greater than or equal to 1 mm, so as to ensure the current flow capacity of the battery cell 10 while ensuring the convenience and reliability of welding.

[0298] Regarding the size and number of the first through-holes 12130, in the embodiments of the present application, the size and specific position of the first through-holes 12130 on the second receiving groove 12120 are not limited, and can be designed according to the number of the first through-holes 12130. For example, the width of the first through-hole 12130 can be greater than or equal to 2 mm, which is conducive to the passage of the conductive portion 22. For example, when there is only one first through-hole 12130 opened on the second receiving groove 12120, in some examples, in conjunction with Figures 21 and 22, the first through-hole 12130 can be centered relative to the second receiving groove 12120. In other examples, in conjunction with Figure 23, the first through-hole 12130 can also be offset relative to the center of the second receiving groove 12120. For example, in some embodiments, in combination with Figure 23, the first through-hole 12130 can be opened at the edge of the second end wall 12121 to be arranged close to the second side wall 12123, so as to increase the available area of ​​the second end wall 12121 and increase the welding area between the conductive part 22 and the second end wall 12121.

[0299] It is understood that after the conductive portion 22 passes through the first through-hole 12130, it will be folded in order to fit the second end wall 12121, but the direction of the folding is not limited. For example, when the first through-hole 12130 is centrally located relative to the second receiving groove 12120, the conductive portion 22 can be folded toward either side of the first through-hole 12130 after passing through the first through-hole 12130 (see Figure 21), thereby appropriately reducing the size of the second receiving groove 12120 and enhancing the structural compactness and strength. Alternatively, after passing through the first through-hole 12130, the conductive portion 22 can be folded toward opposite sides simultaneously (see Figure 24) to reduce the thickness of the weld, reduce the welding heat input, and thus reduce problems such as particle splashing.

[0300] For example, when there are multiple first through-holes 12130 provided on the second receiving groove 12120, the length directions of the multiple first through-holes 12130 are arranged in parallel or substantially parallel to make full use of the space. In this case, the folding direction of the conductive portion 22 after passing through the first through-hole 12130 can be set according to the relative positional relationship of the multiple first through-holes 12130. For example, when there are two first through-holes 12130 provided on the second receiving groove 12120 and they are far away from each other (see FIG. 25 ), the two conductive portions 22 passing through the two first through-holes 12130 can be folded in a direction toward each other; and when there are two first through-holes 12130 provided on the second receiving groove 12120 and they are close to each other, the two conductive portions 22 passing through the two first through-holes 12130 can be folded in a direction away from each other.

[0301] It is understandable that when there are multiple first through holes 12130 opened on the second receiving groove 12120 , the number of the first poles 12 can be appropriately reduced, thereby reducing costs and reducing the number of processes.

[0302] In addition, in some embodiments, in combination with Figures 23 and 24, the first perforation 12130 can be centered relative to the active material coating portion 21, but the position of the first perforation 12130 relative to the second accommodating groove 12120 is not limited and can be centered or offset. Since the first perforation 12130 is centered relative to the active material coating portion 21, the conductive portion 22 can be retracted corresponding to the center line position of the active material coating portion 21.

[0303] In some embodiments, referring to FIG24 , a sealing member 6 may be provided at the first through-hole 12130 to prevent leakage of electrolyte from the housing 11 through the first through-hole 12130. The material, shape, and connection method of the sealing member 6 to the first through-hole 12130 are not limited and may be designed according to actual requirements.

[0304] In combination with Figures 26 and 27, in some embodiments of the present application, when the accommodating portion 121 has the second accommodating groove 12120 of any of the above embodiments, optionally, the shell assembly 1 may further include a first cover plate 13, the first cover plate 13 cooperates with the first pole 12 and closes the notch of the second accommodating groove 12120, and the first cover plate 13 is electrically connected to the first pole 12.

[0305] In the above technical solution, by providing the first cover plate 13 to close the notch of the second receiving tank 12120, the electrolyte in the shell 11 can be prevented from leaking from the notch of the second receiving tank 12120. Moreover, since the first cover plate 13 closes the notch of the second receiving tank 12120 and is electrically connected to the first pole 12, the first cover plate 13 can be used to easily realize the indirect electrical connection between the first pole 12 and the busbar component, and it is beneficial to increase the connection area of ​​the electrical connection, thereby helping to reduce the resistance of the electrical connection.

[0306] It is worth noting that the manner and position of the first cover plate 13 and the first terminal 12 are not limited, as long as the first cover plate 13 can seal the notch of the second receiving groove 12120. For example, in some embodiments, with reference to FIG25 , the first cover plate 13 can be welded to the first terminal 12. During processing, the conductive portion 22 can first be passed through the first through-hole 12130 and welded to the wall of the second receiving groove 12120. Then, the first cover plate 13 and the first terminal 12 are welded to close the notch of the second receiving groove 12120.

[0307] It should also be noted that the specific structure of the first cover plate 13 is not limited. For example, in some optional embodiments, referring to Figures 27-29, the first cover plate 13 includes a first conductive member 131 and a second conductive member 132 made of different materials. The first conductive member 131 is engaged with and electrically connected to the first pole 12, and the second conductive member 132 is engaged with and electrically connected to the first conductive member 131.

[0308] In the above technical solution, the first cover plate 13 is configured as a composite form, and the first conductive member 131 is configured to be made of the same material as the first pole 12, thereby facilitating electrical connection between the first conductive member 131 and the first pole 12. For example, the first conductive member 131 can be easily and reliably and stably connected to the first pole 12 through welding. Furthermore, because the second conductive member 132 is made of a different material than the first conductive member 131, it is convenient to utilize the second conductive member 132 to electrically connect to a busbar component made of a different material than the first pole 12. For example, the second conductive member 132 can be easily and reliably and stably connected to a busbar component made of the same material as the second conductive member 132 through welding.

[0309] For example, when the first pole 12 is a negative pole, the first pole 12 is a copper pole, and the current collector is an aluminum sheet, the first conductive member 131 can be set to copper and the second conductive member 132 can be set to aluminum. In this case, the first pole 12 and the first conductive member 131 are made of the same material and can be effectively welded, and the second conductive member 132 and the current collector are made of the same material and can be effectively welded, thereby effectively achieving an indirect electrical connection between the first pole 12 and the current collector through the first cover 13. Moreover, the copper-to-copper welding of the first pole 12 and the first conductive member 131 has good fluidity and is less likely to crack, which helps to improve the sealing effect of the weld.

[0310] Referring again to Figures 27-29 , in some optional examples, the first conductive member 131 is located between the second receiving groove 12120 and the second conductive member 132. In the above technical solution, since the first conductive member 131 is located between the second receiving groove 12120 and the second conductive member 132, it can separate the second receiving groove 12120 from the second conductive member 132. Therefore, when the electrolyte in the housing 11 enters the second receiving groove 12120 through the first through-hole 12130, the first conductive member 131 can prevent this portion of the electrolyte from contacting the second conductive member 132, thereby solving the problem of electrolyte corrosion on the second conductive member 132.

[0311] It is worth noting that the coupling method between the first conductive member 131 and the second conductive member 132 is not limited. For example, in some embodiments, referring to Figures 27-29, the first conductive member 131 has a second groove 1311, and the second conductive member 132 is embedded in the second groove 1311. The notch of the second groove 1311 is formed on the surface of the first conductive member 131 away from the second receiving slot 12120, so that the second conductive member 132 is exposed through the notch of the second groove 1311. Alternatively, in other embodiments, the connection method between the first conductive member 131 and the second conductive member 132 can also be a fastening connection, a snap connection, etc.

[0312] It should also be noted that the "exposed" of the second conductive member 132 by the notch of the second groove 1311 means that the first conductive member 131 does not block the second conductive member 132 at the notch position of the second groove 1311, and the second conductive member 132 is not required to protrude from the notch of the second groove 1311. For example, the second conductive member 132 can be flush with the surface of the first conductive member 131 on the side away from the second accommodating groove 12120, or the second conductive member 132 can protrude from the surface of the first conductive member 131 on the side away from the second accommodating groove 12120.

[0313] In the above technical solution, on the one hand, by embedding the second conductive member 132 within the first conductive member 131, the difficulty of assembling the first conductive member 131 and the second conductive member 132 can be reduced, the stability and convenience of the cooperation between the first conductive member 131 and the second conductive member 132 can be improved, and the thickness of the first cover plate 13 can be reduced, reducing the space occupied by the first cover plate 13, thereby improving the space utilization of the battery cell 10. On the other hand, since the second conductive member 132 can be exposed from the surface of the first conductive member 131 on the side away from the second receiving groove 12120 through the notch of the second groove 1311, it is convenient to achieve electrical connection between the second conductive member 132 and the current collecting component outside the first terminal 12.

[0314] In addition, since the notch of the second groove 1311 is formed on the surface of the first conductive member 131 on the side away from the second receiving groove 12120, it means that the second groove 1311 is open in the direction away from the active material coating portion 21, so that the portion of the groove wall of the first conductive member 131 used to define the second groove 1311 is located between the second receiving groove 12120 and the second conductive member 132 to separate the second receiving groove 12120 and the second conductive member 132, thereby preventing the electrolyte entering the second groove 1311 from contacting the second conductive member 132, thereby reducing leakage of the electrolyte.

[0315] Of course, in other embodiments, the first cover plate 13 may not be a composite form composed of multiple materials. For example, in other embodiments of the present application, combined with Figure 30, the first cover plate 13 as a whole can also be set to a non-composite form made of the same material, such as for adapting to the positive electrode column, which will not be elaborated here.

[0316] Referring again to Figures 27-29 , in some embodiments, the first cover plate 13 is further embedded in the notch of the second receiving groove 12120. In the above technical solution, by embedding the first cover plate 13 in the second receiving groove 12120, the difficulty of assembling the first cover plate 13 and the first pole 12 can be reduced, the assembly stability of the first cover plate 13 and the first pole 12 can be improved, as well as the reliability and convenience of the connection. In addition, the space occupied by the first cover plate 13 outside the first pole 12 can be reduced. Moreover, because the first cover plate 13 is embedded in the notch of the second receiving groove 12120, there is sufficient space in the second receiving groove 12120 to accommodate the conductive portion 22.

[0317] Of course, in other embodiments of the present application, the cooperation manner of the first cover plate 13 and the first pole 12 is not limited to being embedded in the second receiving groove 12120. The first cover plate 13 can also be directly covered outside the first pole 12, that is, directly covered at the notch of the second receiving groove 12120, so as to facilitate cooperation with the convergence component of the battery 100. This is not limited in this embodiment.

[0318] Referring again to Figures 27-29 , optionally, in an embodiment of the present application, at least a portion of the wall surface at the notch of the second receiving groove 12120 formed on the first pole 12 is a guide slope 12126. The guide slope 12126 is used to guide the first cover plate 13 to mate with the notch of the second receiving groove 12120. In the above technical solution, by processing the wall surface at the notch of the second receiving groove 12120 into a guiding slope, the difficulty of assembling the first cover plate 13 and the second receiving groove 12120 can be reduced, and the efficiency of assembling the first cover plate 13 and the second receiving groove 12120 can be improved. Moreover, when the first cover plate 13 is welded to the guide slope 12126, the area of ​​the weld can be increased, thereby improving the reliability of the weld connection between the first cover plate 13 and the first pole 12 and alleviating the problems of molten pool collapse or laser penetration into the first pole 12 during welding.

[0319] 27-29 , the second receiving groove 12120 includes a first groove section 12124 and a second groove section 12125 located on a side of the first groove section 12124 closer to the pole outer end surface 123. The cross-sectional area of ​​the second groove section 12125 is larger than that of the first groove section 12124, giving the second receiving groove 12120 a stepped groove shape. Furthermore, a stepped surface 12127 is formed at the junction of the first groove section 12124 and the second groove section 12125. This allows the first cover plate 13, when embedded in the second receiving groove 12120, to be embedded in the second groove section 12125 and supported by the stepped surface 12127.

[0320] In the above technical solution, by setting the second accommodating groove 12120 to a stepped groove form, the first cover plate 13 can be stably fitted in the groove position of the second accommodating groove 12120, thereby improving the connection stability between the first cover plate 13 and the first pole 12, and by limiting the groove depth of the first groove section 12124, there is relatively sufficient space in the second accommodating groove 12120 to accommodate the conductive part 22.

[0321] Furthermore, when the wall surface at the slot of the second accommodating slot 12120 formed by the first pole 12 is a guide slope 12126, the cross-sectional area of ​​the second slot segment 12125 can be set to gradually increase in the direction approaching the outer end face 123 of the pole, so that the side wall of the second slot segment 12125 is formed as a guide slope 12126, thereby facilitating processing and simply and effectively meeting the guidance requirements.

[0322] Referring again to Figures 27-29 , in the embodiment of the present application, the first cover plate 13 may further include stress relief grooves 133 as needed. The stress relief grooves 133 are located in the outer peripheral area of ​​the first cover plate 13 to assist in stress relief for the first cover plate 13. In the above technical solution, by providing the stress relief grooves 133 on the first cover plate 13, stress generated during the processing of the first cover plate 13 itself or during the electrical connection between the first cover plate 13 and the first terminal 12 can be relieved, thereby improving issues such as deformation or damage to the first cover plate 13 caused by stress.

[0323] Specifically, when the first cover plate 13 and the second receiving groove 12120 are embedded and welded, the stress relief groove 133 can be used to release the stress generated by the welding, improve the transverse heat conduction, and reduce the probability of damage or deformation of the first cover plate 13. At the same time, when the first cover plate 13 is a composite form including the first conductive member 131 and the second conductive member 132, the stress relief groove 133 can be set on the first conductive member 131 and located in the peripheral area of ​​the second conductive member 132. When the first conductive member 131 and the second receiving groove 12120 are embedded and welded, the stress relief groove 133 can be used to release the stress generated by the welding, improve the transverse heat conduction, and reduce the probability of damage or deformation of the second conductive member 132. Moreover, when the second conductive member 132 and the first conductive member 131 are embedded and welded, the stress relief groove 133 can be used to release the stress generated by the welding, improve the transverse heat conduction, and reduce the probability of deformation of the first conductive member 131, which may result in the first conductive member 131 being unable to be embedded in the second receiving groove 12120.

[0324] 30-31 , in an embodiment of the present application, the housing assembly 1 may further be provided with a second cover plate 14 as required, and the second cover plate 14 covers the first through-hole 12130 and the conductive portion 22 located in the second receiving groove 12120 .

[0325] It is worth noting that when the housing assembly 1 includes the second cover plate 14, the housing assembly 1 may or may not include the first cover plate 13. Furthermore, when the housing assembly 1 includes both the second cover plate 14 and the first cover plate 13, the first cover plate 13 may be a composite of multiple materials or a non-composite of the same material.

[0326] In the above technical solution, at least a portion of the conductive portion 22 is located in the second receiving groove 12120, and the second cover plate 14 covers the conductive portion 22 of this portion. The second cover plate 14 also covers the first perforation 12130, so that when the electrolyte enters the second receiving groove 12120 from the first perforation 12130, the second cover plate 14 can improve the problem of overflow of this portion of the electrolyte from the first pole 12, thereby improving the reliability of the battery cell 10.

[0327] For example, as shown in Figures 30 and 31 , when a portion of the conductive portion 22 is sandwiched between the second cover plate 14 and the second end wall 12121, laser welding can be used to weld the portion of the conductive portion 22, the second cover plate 14, and the second end wall 12121 together to improve the reliability of the connection between the first pole 12 and the conductive portion 22. Furthermore, because the second cover plate 14 can compress the conductive portion 22, the second cover plate 14 can be used to improve the stability of the conductive portion 22 within the second receiving groove 12120.

[0328] In the embodiment of the present application, the first pole 12 can be an integrally formed pole or a composite pole formed in separate parts. Referring again to Figures 30 and 31 , for example, the first pole 12 can include a first pole portion 124 and a second pole portion 125 made of different materials and electrically connected. The second pole portion 125 is located on a side of the first pole portion 124 away from the active material coating portion 21. The receiving portion 121 is provided on the first pole portion 124, or the receiving portion 121 is provided on the first pole portion 124 and the second pole portion 125. The conductive portion 22 is electrically connected to the first pole portion 124.

[0329] In the above technical solution, by setting the first pole 12 as a composite form composed of different materials, the first pole portion 124 located on the inner side is accommodated and electrically connected to the conductive portion 22, and the second pole portion 125 located on the outer side is electrically connected to the busbar component, etc., which is conducive to the assembly and electrical connection of the first pole 12 with related components, reducing the mutual interference between the electrical connection position of the first pole 12 and the conductive portion 22 and the electrical connection position of the first pole 12 and the busbar component of the battery 100, thereby improving the reliability and stability of the battery cell 10.

[0330] For example, when the material of the conductive part 22 is different from the material of the busbar component, the first pole part 124 can be set to the same material as the conductive part 22, and the second pole part 125 can be set to the same material as the busbar component, which is conducive to the welding of the second pole part 125 and the busbar component, and the welding of the first pole part 124 and the conductive part 22, thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole 12, as well as the reliability and stability of the electrical connection between the first pole 12 and the busbar component.

[0331] Furthermore, when the first pole 12 is a composite form of the above embodiments and has the second receiving groove 12120 and the first through-hole 12130 of any of the above embodiments, in some embodiments, the housing assembly 1 may also include the second cover plate 14 of any of the above embodiments. In this case, the second cover plate 14 and the first pole portion 124 may be made of the same material, and the first pole portion 124 and the second cover plate 14 may be electrically connected, thereby improving the reliability and stability of the electrical connection between the first pole portion 124 and the second cover plate 14. For example, the first pole portion 124 and the second cover plate 14 may be connected by welding.

[0332] For example, in combination with Figures 30-31, when the first pole 12 is a negative pole, the first pole portion 124 is made of copper, the second pole portion 125 is made of aluminum, and the conduit component is an aluminum sheet, then the second cover plate 14 can be set to copper, and the first cover plate 13 can be set to aluminum. At this time, the second cover plate 14 and the first pole portion 124 are made of the same material and can be effectively welded, the second pole portion 125 and the first cover plate 13 are made of the same material and can be effectively welded, and the first cover plate 13 and the conduit component are made of the same material and can be effectively welded.

[0333] In an embodiment of the present application, when the accommodating portion 121 has a second accommodating groove 12120, the matching conditions between the battery cell assembly 2 and the second accommodating groove 12120 are not limited according to the different structures of the battery cell assembly 2, and may include, but are not limited to, the following third and fourth embodiments.

[0334] 32 , in the third embodiment, the active material coating portion 21 includes a current collector 211 and an active material layer 212 disposed on the current collector 211. The conductive portion 22 includes a tab portion 221 electrically connected to the current collector 211. The tab portion 221 includes a plurality of tabs 2211. The tabs 2211 converge near the current collector 211 to form a first gathered portion 2212. The tabs 2211 converge and connect to form a second gathered portion 2213 away from the current collector 211. The first gathered portion 2212 connects the second gathered portion 2213 and the active material coating portion 21. When the receiving portion 121 includes a second receiving groove 12120, at least a portion of the second gathered portion 2213 is received within the second receiving groove 12120.

[0335] It is worth noting that the specific structure of the battery cell assembly 2 in this third embodiment is substantially the same as that of the battery cell assembly 2 in the first embodiment above. For details, reference may be made to the description of the first embodiment and will not be repeated here. In this third embodiment, because the tab portion 221 includes a second gathered portion 2213 formed by converging and connecting a plurality of tab sheets 2211, at least a portion of the second gathered portion 2213 can be easily accommodated within the second receiving groove 12120, facilitating assembly of the conductive portion 22 with the first pole 12.

[0336] In some optional examples, in combination with Figure 32, the position where the first gathering portion 2212 and the second gathering portion 2213 are connected can be set corresponding to the first through-hole 12130, that is, on the projection plane perpendicular to the axial direction R of the first pole 12, the orthographic projection of the position where the first gathering portion 2212 and the second gathering portion 2213 are connected is located within the orthographic projection range of the first through-hole 12130, thereby facilitating the second gathering portion 2213 to extend into the first through-hole 12130 at a shorter distance and enter the second accommodating groove 12120, thereby reducing redundancy and reducing costs.

[0337] It is understood that the folding position of the tab 2211 can be designed based on the position of the first through-hole 12130, for example, by adopting the symmetrical folding method described above or the asymmetrical folding method, so that the position where the first folding portion 2212 and the second folding portion 2213 connect is aligned with the first through-hole 12130. This will not be described in detail here. Furthermore, as mentioned above, when the second folding portion 2213 is formed into a sheet structure using ultrasonic pre-welding, it is easier for the second folding portion 2213 to pass through the first through-hole 12130.

[0338] In conjunction with Figure 32, in this third embodiment, in addition to the second accommodating groove 12120, the accommodating portion 121 may also have a third accommodating groove 12140. The third accommodating groove 12140 is located on the side of the second accommodating groove 12120 close to the active material coating portion 21. The surface of the first pole 12 facing the active material coating portion 21 is the pole inner end face 122, and the notch of the third accommodating groove 12140 is formed on the pole inner end face 122. The third accommodating groove 12140 is connected to the second accommodating groove 12120 through the first through-hole 12130. At this time, at least part of the first retracted portion 2212 can be accommodated in the third accommodating groove 12140.

[0339] In the above technical solution, at least a portion of the first folded portion 2212 of the pole ear portion 221 is accommodated in the third accommodating groove 12140, and at least a portion of the second folded portion 2213 is accommodated in the second accommodating groove 12120, so that the space in the first pole 12 can be more fully utilized, and the space occupied by the pole ear portion 221 in the shell 11 can be further reduced to accommodate a larger active material coating portion 21, thereby improving the energy density of the battery cell 10, and can better reduce the redundancy of the pole ear portion 221 in the shell 11, further reduce the probability of short circuit between the pole ear portion 221 and the active material coating portion 21, and further reduce the risk of the pole ear portion 221 being inverted toward the active material coating portion 21.

[0340] It should be noted that the specific shape of the third receiving groove 12140 is not limited and can be regular or irregular, such as a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a hemispherical groove with an elliptical cross-section and gradually changing cross-sectional dimensions, etc. In some embodiments of the present application, the third receiving groove 12140 can be configured with a cross-sectional shape in which the length is greater than the width, such as a rectangular, elliptical, or oblong shape, to facilitate the storage of the first gathering portion 2212.

[0341] In a third embodiment, the second folded portion 2213 is electrically connected directly or indirectly to the first terminal 12. For example, when the second folded portion 2213 is electrically connected directly to the first terminal 12, such as when the second folded portion 2213 is welded to the first terminal 12, the structure of the battery cell assembly 2 can be simplified, reducing parts, simplifying the assembly process, and improving assembly efficiency. The method and location of the direct electrical connection between the second folded portion 2213 and the first terminal 12 are not limited. For example, the electrical connection position between the second gathering portion 2213 and the first pole 12 can be located at the second end wall 12121 and / or the second side wall 12123. Furthermore, the electrical connection position between the second gathering portion 2213 and the second end wall 12121 can extend along the length direction or width direction of the second end wall 12121. Further, the second end wall 12121 has a second groove 12122, and the electrical connection position between the second gathering portion 2213 and the second end wall 12121 can be located in the second groove 12122, and so on. The corresponding technical effects can be referred to the introduction of the above embodiments and will not be repeated here.

[0342] As an optional solution, the conductive portion 22 may also be provided with a transition piece 222 as required. In this case, the second retracted portion 2213 is indirectly electrically connected to the first pole 12. Specifically, with reference to FIG33 , when the conductive portion 22 includes the transition piece 222, the transition piece 222 is connected to the second retracted portion 2213, and the conductive portion 22 is electrically connected to the first pole 12 via the transition piece 222. In this case, at least a portion of the transition piece 222 is accommodated within the second receiving groove 12120. In this example, at least a portion of the second retracted portion 2213 is also accommodated within the second receiving groove 12120.

[0343] In the above technical solution, the active material coating portion 21 can be electrically connected to the first electrode 12 through the first gathered portion 2212, the second gathered portion 2213, and the adapter plate 222 in sequence. The location where the conductive portion 22 is electrically connected to the first electrode 12 is located on the adapter plate 222. For example, the electrical connection can be achieved by welding (e.g., laser welding) the adapter plate 222 to the first electrode 12. In addition, the adapter plate 222 and the tab 2211 are two separate components and are connected by welding (e.g., ultrasonic welding).

[0344] In the above technical solution, by accommodating at least a portion of the second folded portion 2213 and at least a portion of the adapter plate 222 within the second receiving groove 12120, the space within the first terminal 12 can be more fully utilized, further reducing the space occupied by the conductive portion 22 within the housing 11, thereby further improving the volumetric energy density of the battery cell 10. Furthermore, by providing the adapter plate 222 with a sheet structure, the adapter plate 222 can be easily inserted through the first through-hole 12130 and extended into the second receiving groove 12120.

[0345] In addition, by using the adapter plate 222 to achieve indirect electrical connection between the second retracted portion 2213 and the first pole 12, the adapter plate 222 can be welded to the first pole 12 at a position avoiding the second retracted portion 2213, so that the welding between the adapter plate 222 and the first pole 12 is firm, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, by electrically connecting the first pole 12 and the pole tab 2211 through the adapter plate 222, the structure of the pole tab 2211 can also be simplified.

[0346] Among them, the direct electrical connection method and position of the adapter plate 222 and the first pole 12 are not limited. For example, the adapter plate 222 is electrically connected to the first pole 12 by welding. For example, the electrical connection position of the adapter plate 222 and the first pole 12 can be located at the second end wall 12121 and / or the second side wall 12123. Further, the position where the adapter plate 222 is electrically connected to the second end wall 12121 can extend along the length direction or width direction of the second end wall 12121. Further, the second end wall 12121 has a second sink 12122, and the position where the adapter plate 222 is electrically connected to the second end wall 12121 can be located in the second sink 12122, etc. The corresponding technical effects can be referred to the introduction of the above embodiment and will not be repeated here. When the electrical connection position between the adapter plate 222 and the first pole 12 is located at the second end wall 12121 and / or the second side wall 12123, since at least part of the adapter plate 222 is accommodated in the second accommodating groove 12120, the structure of the adapter plate 222 can be simplified, redundancy can be reduced, and cost can be lowered.

[0347] 33 , in the fourth embodiment, the active material coating portion 21 includes a current collector 211 and an active material layer 212 disposed on the current collector 211. The conductive portion 22 includes a tab portion 221 and a transition piece 222. The tab portion 221 includes a plurality of tabs 2211 electrically connected to the current collector 211. The plurality of tabs 2211 converge near the current collector 211 to form a first gathered portion 2212. The plurality of tabs 2211 converge and connect to form a second gathered portion 2213 away from the current collector 211. The transition piece 222 is electrically connected to the second gathered portion 2213. When the accommodating portion 121 has a second accommodating groove 12120, at least a portion of the transition piece 222 can be accommodated in the second accommodating groove 12120 and electrically connected to the first electrode 12.

[0348] In the above technical solution, compared with the above third solution including the adapter plate 222, in this fourth solution, at least part of the adapter plate 222 is accommodated in the second accommodating groove 12120, but the relative position of the pole ear portion 221 and the second accommodating groove 12120 is not limited, that is, at least part of the pole ear portion 221 can be accommodated in the second accommodating groove 12120, and the pole ear portion 221 can also be completely located outside the second accommodating groove 12120, thereby meeting different structural design requirements.

[0349] In the above technical solution, by accommodating at least a portion of the adapter plate 222 in the second accommodating groove 12120, the adapter plate 222 can occupy the space in the first pole 12, thereby reducing the space occupied by the adapter plate 222 in the shell 11 to accommodate a larger active material coating part 21, thereby improving the energy density of the battery cell 10, and reducing the probability of short-circuiting between the adapter plate 222 and the active material coating part 21, reducing the risk of short-circuiting the battery cell assembly 2, and improving the stability and reliability of the battery cell 10.

[0350] In addition, by using the adapter plate 222 to achieve indirect electrical connection between the second retracted portion 2213 and the first pole 12, the adapter plate 222 can be welded to the first pole 12 at a position avoiding the second retracted portion 2213, so that the welding between the adapter plate 222 and the first pole 12 is firm, the risk of welding cracking is small, and the reliability and stability of the battery cell 10 can be further improved; at the same time, by electrically connecting the first pole 12 and the pole tab 2211 through the adapter plate 222, the structure of the pole tab 2211 can also be simplified.

[0351] In combination with Figure 34, in some other embodiments of the present application, the accommodating portion 121 has a fourth accommodating groove 12150, the surface of the first pole 12 away from the active material coating portion 21 is the pole outer end face 123, the notch of the fourth accommodating groove 12150 is formed on the pole outer end face 123, the fourth accommodating groove 12150 is connected to the interior of the shell 11 through the second through-hole 12160, the conductive portion 22 may not be accommodated in the fourth accommodating groove 12150, for example, the conductive portion 22 may be passed through the second through-hole 12160, and the electrical connection position between the conductive portion 22 and the first pole 12 is located at the hole wall of the second through-hole 12160 formed by the first pole 12.

[0352] In the above embodiment, by providing the fourth receiving groove 12150, it is possible to easily achieve electrical connection between the conductive portion 22 and the wall of the second through-hole 12160. Furthermore, in some cases, the electrical connection between the conductive portion 22 and the first electrode 12 can be utilized to seal the second through-hole 12160. For example, the conductive portion 22 can be welded to the wall of the second through-hole 12160 at the location where the second through-hole 12160 connects to the fourth receiving groove 12150, thereby facilitating the operation. Furthermore, by controlling the weld mark, the weld mark and the conductive portion 22 can be utilized to seal the second through-hole 12160, thereby improving the problem of electrolyte leakage from the housing 11 through the second through-hole 12160.

[0353] It should be noted that the specific shape of the fourth accommodating groove 12150 is not limited, and can be a regular shape or an irregular shape, such as a cylindrical groove with a rectangular, elliptical, or oblong cross-section, or a trapezoidal groove with a rectangular cross-section and a gradually changing cross-sectional size, or a hemispherical groove with a circular cross-section and a gradually changing cross-sectional size, or a semi-ellipsoidal groove with an elliptical cross-section and a gradually changing cross-sectional size, etc.

[0354] In the embodiment of the present application, the second through-hole 12160 can be in the form of an elongated strip to match the shape of the sheet-shaped portion of the conductive portion 22, thereby facilitating the passage of the sheet-shaped portion of the conductive portion 22. Furthermore, when the second through-hole 12160 is in the form of an elongated strip, the fourth receiving groove 12150 can also be configured in a shape where the cross-section is longer than the width, such as a rectangle, an ellipse, an oblong, etc. In this case, the length direction of the second through-hole 12160 can be set to coincide with the length direction of the cross-section of the fourth receiving groove 12150, thereby fully utilizing the space.

[0355] It should be noted that the accommodating portion 121 of the embodiment of the present application is not limited to the above-mentioned form of having at least one accommodating groove. For example, in some other embodiments of the present application, in conjunction with Figure 35, the accommodating portion 121 may only have a third through-hole 12170, the surface of the first pole 12 facing the active material coating portion 21 is the pole inner end face 122, the surface of the first pole 12 away from the active material coating portion 21 is the pole outer end face 123, the third through-hole 12170 is in the form of a through-hole and passes through the pole inner end face 122 and the pole outer end face 123, and at least a portion of the conductive portion 22 is provided in the third through-hole 12170. Among them, the electrical connection position between the conductive portion 22 and the first pole 12 is not limited. For example, the electrical connection position can be located on the hole wall of the first pole 12 forming the third through-hole 12170, or the conductive portion 22 can also pass through the third through-hole 12170 so that the electrical connection position is located on the pole outer end face 123 outside the third through-hole 12170, etc. Furthermore, the shape of the third through-hole 12170 is not limited and can be a regular hole with a uniform cross-section, or a hole with a variable cross-section with unequal cross-sections, etc. Furthermore, the cross-sectional shape of the third through-hole 12170 is not limited and can be, for example, an elongated strip, such as a rectangle, an ellipse, or an oblong, etc., to match the shape of the sheet-like portion of the conductive portion 22, thereby facilitating the insertion of the sheet-like portion of the conductive portion 22 through the third through-hole 12170. This will not be described in detail here.

[0356] In conjunction with Figures 36-38, in some embodiments of the present application, the battery cell 10 also includes a bracket 3, which is located in the shell 11, and the bracket 3 is located on the side of the active material coating part 21 close to the first pole 12. The bracket 3 has an avoidance hole 31 for avoiding the conductive part 22. The conductive part 22 can pass through the avoidance hole 31 and extend to the side of the bracket 3 away from the active material coating part 21 to be welded with the first pole 12, thereby ensuring the normal charging and discharging operations of the battery cell 10.

[0357] In the above technical solution, a bracket 3 is provided on the side of the active material coating portion 21 close to the first pole 12, so that the bracket 3 can be used to separate the active material coating portion 21 from the shell 11, thereby improving the reliability of the battery cell 10, and an avoidance hole 31 is provided on the bracket 3, which can guide and constrain the conductive portion 22 to cooperate with the first pole 12 by passing through the avoidance hole 31, thereby eliminating the need for the conductive portion 22 to bypass the edge of the bracket 3 to approach the first pole 12, thereby simplifying the arrangement of the conductive portion 22, saving material of the conductive portion 22, and reducing costs, and also supporting and guiding the conductive portion 22 to cooperate with the first pole 12 by the bracket 3, which can reduce the risk of short-circuiting between the conductive portion 22 and the active material coating portion 21, thereby further improving the reliability of the battery cell 10.

[0358] 36 to 38 , optionally, the bracket 3 is provided with a guide portion 32 , the guide portion 32 surrounds at least a portion of the avoidance hole 31 , and the guide portion 32 at least partially extends to the accommodating portion 121 .

[0359] It is worth noting that the guide portion 32 protrudes from the bracket 3 and extends into the accommodating portion 121, and at least a portion of the avoidance hole 31 is formed in the guide portion 32, so that when the conductive portion 22 is passed through the avoidance hole 31, at least a portion of the conductive portion 22 can be easily received in the accommodating portion 121, thereby improving the assembly efficiency of the conductive portion 22; at the same time, through the provision of the guide portion 32, the cooperation between the bracket 3 and the first pole 12, and between the bracket 3 and the conductive portion 22 are tighter and more reliable, making the structure of the battery cell 10 more compact, which is more conducive to the improvement of the energy density of the battery cell 10.

[0360] 36 to 38 , optionally, a third groove 38 is provided on the bracket 3 , and at least a portion of the first pole 12 located in the housing 11 is accommodated in the third groove 38 .

[0361] In the above technical solution, by providing a third groove 38 on the bracket 3, at least a portion of the first pole 12 located in the shell 11 is accommodated in the third groove 38 of the bracket 3, thereby improving the compactness of the structure, helping to reduce the space occupied by the bracket 3 in the shell 11, and helping to improve the volume energy density of the battery cell 10.

[0362] In addition, in some embodiments, the guide portion 32 can be used to participate in defining the third groove 38, thereby simplifying the structure of the bracket 3, reducing the design and processing difficulty of the bracket 3, and facilitating increasing the wall thickness of the guide portion 32 and improving the guiding reliability of the conductive portion 32.

[0363] 36-38 , optionally, the avoidance hole 31 includes a first hole segment 311 and a second hole segment 312 , the second hole segment 312 is located on a side of the first hole segment 311 close to the active material coating portion 21 , and the cross-sectional area of ​​the second hole segment 312 gradually increases in a direction away from the first hole segment 311 . When the active material coating portion 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211, the conductive portion 22 includes a pole ear portion 221 electrically connected to the current collector 211, the pole ear portion 221 includes a plurality of pole ear sheets 2211, the plurality of pole ear sheets 2211 converge near the current collector 211 to form a first gathered portion 2212, the plurality of pole ear sheets 2211 converge and connect away from the current collector 211 to form a second gathered portion 2213, and when the first gathered portion 2212 connects the second gathered portion 2213 and the active material coating portion 21, at least a portion of the first gathered portion 2212 can be accommodated in the second hole segment 312, and the second gathered portion 2213 can be passed through the first hole segment 311.

[0364] In the above technical solution, by configuring the avoidance hole 31 to include a second hole segment 312 that gradually expands toward the active material coating portion 21, the second hole segment 312 can accommodate more first retracted portions 2212, thereby improving the compactness of the support 3 and the battery cell assembly 2. This reduces the overall volume of the battery cells 10, allowing the battery 100 to accommodate a larger number of battery cells 10, thereby increasing the volumetric energy density of the battery 100. Furthermore, in the above technical solution, the specific explanations of the first retracted portions 2212 and the second retracted portions 2213 have been described in the previous embodiments and will not be repeated here.

[0365] In some embodiments of the present application, the bracket 3 may be an integral structure or a split structure. Referring to FIG39 , when the bracket 3 is an integral structure, the avoidance hole 31 is formed in the form of a through hole that penetrates the bracket 3. As a result, the integral structure of the bracket 3 is easy to process, and the reliability of the bracket 3 is good. It is also convenient to assemble the bracket 3 with the shell assembly 1, thereby improving assembly efficiency and matching stability. It is understandable that how the bracket 3 is processed can be specifically selected according to the material of the bracket 3. For example, when the bracket 3 is an insulating plastic part, the integral structure of the bracket 3 can be obtained by injection molding.

[0366] Referring to Figure 40 , when the bracket 3 is a split structure, it includes a detachable first bracket 33 and a second bracket 34. Both the first bracket 33 and the second bracket 34 are elongated, plate-like structures that can be removably connected, for example, by plugging or snapping them together for easy assembly. Furthermore, the first bracket 33 has a semi-hole structure on one side near the second bracket 34, and the second bracket 34 also has another semi-hole structure of a matching shape near the first bracket 33. Together, the semi-hole structures of the first bracket 33 and the second bracket 34 form an annular escape hole 31. In other words, the escape hole 31 is defined between the first bracket 33 and the second bracket 34.

[0367] In the above technical solution, the avoidance hole 31 is defined by the cooperation of the first bracket 33 and the second bracket 34. When the bracket 3 is assembled with the battery cell assembly 2, there is no need to pass the conductive part 22 from one end of the avoidance hole 31 to the other end. Instead, the first bracket 33 and the second bracket 34 can be spliced ​​and clamped at the position of the conductive part 22 to make the avoidance hole 31 surround the conductive part 22, thereby facilitating the assembly of the bracket 3 and the battery cell assembly 2 and improving the assembly efficiency.

[0368] As an optional solution, when the cross-section of the avoidance hole 31 is long and strip-shaped, the first bracket 33 and the second bracket 34 are placed on both sides of the avoidance hole 31 in the width direction. For example, if the width direction of the avoidance hole 31 is the left and right direction, the first bracket 33 and the second bracket 34 are located on the left and right sides of the avoidance hole 31, thereby facilitating the cooperation between the first bracket 33, the second bracket 34 and the conductive part 22.

[0369] In conjunction with Figures 36, 41, and 42, in the embodiments of the present application, the configuration of the bracket 3 is not limited thereto. The edge of the bracket 3 facing away from the housing cover 112 may further be provided with a housing entry guide surface 35. The housing entry guide surface 35 comprises an inclined or curved surface, and when orthographically projected along the axial direction R of the first electrode 12, the orthographic projection of the active material coating portion 21 is entirely within the orthographic projection range of the bracket 3, and the orthographic projection range of the bracket 3 exceeds the orthographic projection range of the active material coating portion 21. The housing entry guide surface 35 serves as a guide, allowing the bracket 3 to be smoothly installed into the housing body 111. The bracket 3 enters the housing body 111 first, followed by the active material coating portion 21, thereby reducing the problem of the housing body 111 scratching the active material coating portion 21. During assembly, the bracket 3 and the cell assembly 2 can be preassembled together, and then this preassembled assembly can be installed into the housing 11. During installation, the bracket 3 is located at the front end of the active material coating portion 21, that is, the bracket 3 enters the housing 11 before the active material coating portion 21. This can reduce the difficulty of the bracket 3 entering the housing 11 by utilizing the shell entry guide surface 35. The relatively large projected area of ​​the bracket 3 also protects the active material coating portion 21, reducing the chance of scratching and damage between the active material coating portion 21 and the housing 11, thereby improving assembly efficiency and success rate. In addition, the contact area between the bracket 3 and the active material coating portion 21 can be increased, which can reduce stress concentration problems and eliminate other structural components.

[0370] 41 , in some embodiments of the present application, the battery cell 10 may further include an inner insulating member 4, which is located inside the shell 11 and wrapped around the outside of the active material coating portion 21, and the inner insulating member 4 is connected to the bracket 3. In the above embodiment, on the one hand, by wrapping the inner insulating member 4 around the outside of the active material coating portion 21, the insulation reliability between the active material coating portion 21 and the shell 11 can be improved, the corrosion of the shell 11 caused by the contact between the active material coating portion 21 and the shell 11 can be reduced or prevented, and the leakage of electrolyte caused by the corrosion of the shell 11 can be reduced, thereby improving the reliability of the battery cell 10; on the other hand, by connecting the inner insulating member 4 to the bracket 3, the difficulty of fixing the inner insulating member 4 can be reduced, and the reliability of the inner insulating member 4 wrapped around the outside of the active material coating portion 21 can be improved.

[0371] In conjunction with Figure 41, in an embodiment of the present application, the bracket 3 includes a main body 36 and an extension portion 37. The main body 36 is located on the side of the active material coating portion 21 close to the first pole 12, and the extension portion 37 is connected to the main body 36 and is located in the peripheral area of ​​the active material coating portion 21. On the one hand, the extension portion 37 can be used to limit the active material coating portion 21, and the extension portion 37 is used to improve the problem of carbon powder falling off the edge of the active material coating portion 21 and the corrosion caused by the overlap of the shell 11. On the other hand, the extension portion 37 can also be used to fix the internal insulating part 4, improve the connection reliability between the internal insulating part 4 and the bracket 3, and have a better insulation effect.

[0372] Exemplarily, in combination with Figure 41, the main body 36 and the extension portion 37 can define a positioning groove 39 located on the side of the extension portion 37 away from the active material coating portion 21, and the end of the inner insulating part 4 is embedded in the positioning groove 39 to prevent the inner insulating part 4 from protruding from the edge of the main body 36. In this way, when entering the shell, the main body 36 can be used to protect the inner insulating part 4, reducing the chance of damage to the inner insulating part 4 and the shell 11 due to scratches.

[0373] Specifically, in conjunction with Figure 42, the internal insulating part 4 can be an integrated film, having a main body 41 located on both sides of the active material coating part 21 in the thickness direction and a connecting part 42 connecting the two main body parts 41, the connecting part 42 is located on the side of the active material coating part 21 away from the first pole 12, and the edge of the side of the main body 41 away from the connecting part 42 extends to the extension part 37 and is connected to the extension part 37, so that it has better insulation performance and is easy to connect.

[0374] In some embodiments, the housing assembly 1 includes at least one first pole 12 riveted to the housing body 111 .

[0375] In the above technical solution, since the first terminal 12 is connected to the shell 111 by riveting, welding is difficult when the shell 111 is thin. However, riveting the first terminal 12 to the shell 111 is easier. That is, riveting the first terminal 12 and the shell 111 is simple to install and easy to operate. In addition, riveting the first terminal 12 to the shell 111 facilitates the thinning and lightweight design of the shell 111, thereby reducing the weight of the battery cell 10. When the size of the battery cell 10 is fixed, riveting the first terminal 12 facilitates the thinning of the shell 111 and helps increase the internal space of the shell 111, thereby improving the energy density of the battery cell 10.

[0376] For example, in some embodiments, in combination with Figures 43 to 45, the first pole 12 can be an integrated structure and riveted to the shell 11, thereby improving the assembly efficiency of the first pole 12 and reducing the height of the first pole 12 protruding from the surface of the shell 11, which is beneficial to improving energy density and compactness.

[0377] Specifically, with reference to Figures 43-45 , before riveting, the first pole 12 may include a stopper 1281 and a penetration portion 1282. During assembly, the stopper 1281 is stopped inside the housing 11, and the penetration portion 1282 is penetrated through the mounting hole 113. The portion of the penetration portion 1282 located outside the housing 11 is then riveted to form a flange 1283. The flange 1283 is stopped outside the housing 11, thereby achieving installation of the first pole 12. It should be noted that, in this case, the penetration portion 1282 is the pole body of the first pole 12, the flange 1283 is the first stopper of the first pole 12, and the stopper 1281 is the second stopper of the first pole 12.

[0378] Optionally, referring to Figures 43 and 44 , the housing assembly 1 may include several sealing gaskets, such as the first sealing gasket 191 and the second sealing gasket 192 shown in Figure 43 , that fit between the housing 11 and the first pole 12. The sealing gaskets are assembled in place before riveting. After the first pole 12 is riveted, the first pole 12 presses against the sealing gaskets to form a seal, thereby improving the sealing performance at the joint between the first pole 12 and the housing 11. The number, position, and material of the sealing gaskets are not limited, and the materials may be, for example, silicone, plastic, etc., and are not limited here.

[0379] Optionally, referring to FIG44 , the length c of the flange portion 1283 may be greater than or equal to 1 mm, and the thickness d may be greater than or equal to 2 mm, to improve the riveting strength of the first pole 12. When the length c of the flange portion 1283 is less than 1 mm and / or the thickness d is less than 2 mm, the reliability of the first pole 12 and the housing 11 may be reduced under relatively strong vibration.

[0380] For another example, in other embodiments of the present application, with reference to FIG9 and FIG10 , the first pole 12 may be a split structure that is welded together for installation on the housing 11. For example, the first pole 12 includes a first portion 1291 and a second portion 1292, with at least a portion of the first portion 1291 being stopped outside the housing 11, and at least a portion of the second portion 1292 being stopped inside the housing 11. The first pole 12 may be installed by inserting at least one of the first portion 1291 and the second portion 1292 into the mounting hole 113 and welding (e.g., laser welding) the other portion.

[0381] In some optional embodiments, referring to FIG. 48 and FIG. 49 , there are multiple first poles 12 and all of them are located on the same side surface of the housing 11 , thereby facilitating installation and improving assembly efficiency.

[0382] It should be noted that the arrangement of the multiple first poles 12 on the same side surface is not limited. For example, when the cross-section of the first pole 12 is an elongated structure, for example, a cross-sectional length greater than or equal to three times the cross-sectional width, such as an elliptical, oblong, or rectangular shape, it has better adaptability to the thin and flat shape of the housing 11. For example, the multiple first poles 12 are all provided on a side surface of the housing 11 in the height direction (denoted as the first wall 110), the length direction of each first pole 12 is consistent with the length direction of the first wall 110 of the housing 11, and the multiple first poles 12 are spaced apart along the length direction and / or width direction of the first wall 110.

[0383] For example, in the example shown in FIG48 , when the first wall 110 has two first poles 12, the two first poles 12 are spaced apart along the length of the first wall 110. Optionally, in conjunction with FIG48 , the portion of the first pole 12 located outside the housing 11 (denoted as the pole outer portion) is annular. Along the length of the first wall 110, the inner ring length a1 of the pole outer portion is greater than or equal to 1 / 3 of the length a0 of the first wall 110, and along the width of the first wall 110, the inner ring width b1 of the pole outer portion is greater than or equal to 3 / 4 of the width b0 of the first wall 110. This facilitates providing a larger area for the first pole 12 to electrically connect to the current-carrying component, thereby further improving the current carrying capacity of the first pole 12. For example, the inner ring length a1 of the pole outer portion is greater than or equal to 50 mm, and the inner ring width b1 of the pole outer portion is greater than or equal to 30 mm.

[0384] In addition, with reference to FIG48 , when the first wall 110 has two first poles 12 spaced apart along the length of the first wall 110, in some optional embodiments, the first pole 12 includes a portion located within the housing 11 (denoted as the pole interior). In the lengthwise direction of the first wall 110, the length of the pole interior is greater than or equal to 1 / 3 of the length of the first wall 110, and in the widthwise direction of the first wall 110, the width of the pole interior is greater than or equal to 3 / 4 of the width of the first wall 110. This facilitates providing a larger area for electrical connection with the conductive portion 22, thereby further improving the current carrying capacity of the first pole 12. For example, the length of the pole interior is greater than or equal to 50 mm, and the width of the pole interior is greater than or equal to 30 mm.

[0385] For example, in the example shown in FIG49 , when the first wall 110 has four first poles 12, two of the first poles 12 are spaced apart along the width of the first wall 110 to form a group, for a total of two groups spaced apart along the length of the first wall 110. Optionally, referring to FIG49 , the portion of the first pole 12 located outside the housing 11 (denoted as the pole outer portion) is annular. Along the length of the first wall 110, the inner ring length a2 of the pole outer portion is greater than or equal to 1 / 3 of the length a0 of the first wall 110, and along the width of the first wall 110, the inner ring width b2 of the pole outer portion is greater than or equal to 1 / 5 of the width b0 of the first wall 110. This facilitates providing a larger area for the first pole 12 to electrically connect to the busbar, thereby further improving the current carrying capacity of the first pole 12. For example, the inner ring length a2 of the pole outer portion is greater than or equal to 50 mm, and the inner ring width b2 of the pole outer portion is greater than or equal to 8 mm.

[0386] In addition, with reference to FIG49 , when the first wall 110 has four first poles 12, with two first poles 12 spaced apart along the width of the first wall 110 to form a group, with a total of two groups spaced apart along the length of the first wall 110, in some optional embodiments, the first pole 12 includes a portion located within the housing 11 (denoted as the pole interior). In the length direction of the first wall 110, the length of the pole interior is greater than or equal to 1 / 3 of the length of the first wall 110, and in the width direction of the first wall 110, the width of the pole interior is greater than or equal to 1 / 5 of the width of the first wall 110. This facilitates providing a larger area for the first pole 12 to electrically connect with the conductive portion 22, thereby further improving the current carrying capacity of the first pole 12. For example, the length of the pole interior is greater than or equal to 50 mm, and the width of the pole interior is greater than or equal to 8 mm.

[0387] In some embodiments, referring to Figures 48 and 49 , a portion of the first pole 12 is located inside the housing 11, and a portion of the first pole 12 is located outside the housing 11. The orthographic projection area of ​​the portion of the first pole 12 located outside the housing 11 on the first wall 110 is greater than or equal to 5% of the area of ​​the first wall 110. For example, the orthographic projection area of ​​the portion of the first pole 12 located outside the housing 11 on the first wall 110 is greater than or equal to 5%, 6%, 7%, 8%, 9%, 10%, etc. of the area of ​​the first wall 110. This helps increase the connection area between the first pole 12 and the current busbar, increases the effective flow area between the first pole 12 and the current busbar, and helps increase the charging speed of the battery cell 10.

[0388] In addition, in some embodiments, combined with Figure 50, the vertical height t1 of the portion of the first pole 12 protruding from the outer surface of the first wall 110 (recorded as the pole outside) from the first wall 110 can be less than or equal to 3.2 mm, and the vertical height t2 of the portion of the first pole 12 protruding from the inner surface of the first wall 110 (recorded as the pole inside) from the first wall 110 can be less than or equal to 2 mm, so as to improve the volume energy density of the battery cell 10.

[0389] Please refer to Figures 50 to 56 again. The shell 11 specifically includes a shell body 111 and a shell cover 112. The shell body 111 is a square ring structure, one end or both ends of which are open. When one end is open, there is one shell cover 112, which is set in the open position. When both ends are open, there are two shell covers 112, which are respectively covered at the two open ends of the shell body 111.

[0390] In detail, when the housing 11 includes a body 111 and a cover 112, and one end of the body 111 is open, the body 111 is an integrally formed part, specifically a square structure formed by stretching. In this case, the first pole 12 can be provided on at least one of the body 111 or the cover 112. For example, in conjunction with FIG51, the first pole 12 can be provided at the end of the body 111 away from the cover 112. When the battery cell 10 is used in a vibrating environment, the amplitude of the connection between the body 111 and the cover 112 is small, and the connection between the body 111 and the cover 112 is not easy to crack, which can improve the reliability of the battery cell 10 and can help reduce the wall thickness of the body 111, thereby reducing cost and weight, and helping to achieve miniaturization of the battery cell 10.

[0391] As an optional solution, referring again to Figure 51 , when there are multiple first terminals 12, all first terminals 12 are located at the end of the housing 111 away from the housing cover 112. Thus, when the battery cell 10 is used in a vibrating environment, the amplitude of vibration at the connection between the housing 111 and the housing cover 112 is small, and the connection between the housing 111 and the housing cover 112 is less likely to crack, thereby improving the reliability of the battery cell 10. Furthermore, the wall thickness e1 of the end wall of the housing 111 away from the housing cover 112 can be reduced to less than or equal to 2 mm, and the wall thickness e2 of the side wall of the housing 111 connecting the end wall to the housing cover 112 can be reduced to less than or equal to 0.8 mm. This can reduce cost and weight, and facilitate the miniaturization of the battery cell 10.

[0392] When the first receiving groove 12110 corresponding to the mounting hole 113 is provided on the first pole 12, the wall thickness of the portion of the first pole 12 located on the side of the first receiving groove 12110 away from the active material coating portion 21 is thinner, so that the welding of the conductive portion 22 and the first pole 12 can be achieved from the outside of the shell 11. As shown in Figure 51, for the case where the shell 11 includes a shell body 111 and a shell cover 112, and the shell cover 112 is arranged at the open end of the shell body 111, even if the first pole 12 is arranged at the closed end of the shell body 111, there is no need to worry about the problem of difficulty in welding the conductive portion 22 and the first pole 12 from the inside of the shell 11, because the conductive portion 22 and the first pole 12 can be welded from the outside of the shell 11, so that the connection stability and reliability of the shell body 111 and the shell cover 112 can be improved by arranging the first pole 12 at the closed end of the shell body 111.

[0393] When the above-mentioned second accommodating groove 12120 is opened on the first pole 12, since the welding of the conductive part 22 and the first pole 12 can be achieved from the outside of the shell 11 through the notch of the second accommodating groove 12120, combined with Figure 51, for the shell 11 including the shell body 111 and the shell cover 112, the shell cover 112 is arranged at the open end of the shell body 111, even if the first pole 12 is arranged at the closed end of the shell body 111, there is no need to worry about the difficulty of welding the conductive part 22 and the first pole 12 from the inside of the shell 11, because the conductive part 22 and the first pole 12 can be welded from the outside of the shell 11, so that the connection stability and reliability of the shell body 111 and the shell cover 112 can be improved by arranging the first pole 12 at the closed end of the shell body 111.

[0394] Of course, in conjunction with Figure 52, in other embodiments of the present application, all first poles 12 can also be provided on the shell cover 112 as required. This facilitates the assembly of the first poles 12 and the shell cover 112, which is not limited in this embodiment.

[0395] Please refer to FIG. 6-FIG . 8 , FIG. 21 , and FIG. 26 - FIG. 27 again for a description of the battery cell 10 according to a specific embodiment of the present application.

[0396] 6-8 , the battery cell 10 is a rectangular parallelepiped, with the height of the battery cell 10 being in a first direction Z, the length of the battery cell 10 being in a second direction X, and the thickness of the battery cell 10 being in a third direction Y. The battery cell 10 includes a housing 11, which comprises a body 111 and a cover 112. The body 111 is a square ring-shaped structure, with one end of the body 111 being open along the first direction Z and the other end being closed along the first direction Z. The cover 112 is disposed over the open portion of the body 111.

[0397] Referring to Figures 6-8 , the housing 111 has two poles at its closed end along the first direction Z. The two poles are spaced apart along the second direction X to form a positive pole and a negative pole, respectively. Both poles are first poles 12 provided with a receiving portion 121. The receiving portion 121 includes a second receiving slot 12120. Specifically, the first pole 12 includes a second end wall 12121 and a second side wall 12123. The second end wall 12121 is located on the side of the second side wall 12123 that is closer to the housing cover 112. The second end wall 12121 and the second side wall 12123 enclose the second receiving slot 12120. The surface of the first pole 12 that is away from the housing cover 112 is the pole outer end surface 123. The notch of the second receiving slot 12120 is formed on the pole outer end surface 123. The second end wall 12121 is provided with a first through-hole 12130.

[0398] 8 and 21 , the battery cell 10 further includes a cell assembly 2, which includes an active material coating portion 21 and a pole ear portion 221. The active material coating portion 21 is accommodated in the shell 11, and the pole ear portion 221 extends through the first through-hole 12130 into the second accommodating groove 12120 and is welded to the second end wall 12121 to electrically connect the active material coating portion 21 and the first pole 12 through the pole ear portion 221.

[0399] Referring to Figures 21, 26, and 27, a first cover plate 13 is embedded in the notch of the second receiving slot 12120. After the electrode lug 221 is welded to the second end wall 12121, the first cover plate 13 cooperates with the first terminal 12 to seal the notch of the second receiving slot 12120. The first cover plate 13 is welded to the first terminal 12 to form an electrical connection. Thereafter, when a busbar assembly is used to electrically connect battery cells 10 to battery cells 10, the busbar assembly can be welded to the first cover plate 13 to achieve an electrical connection with the first terminal 12.

[0400] In the above technical solution, on the one hand, the first electrode 12 is provided with a second receiving groove 12120, which can reduce the weight of the first electrode 12 to a certain extent, so as to improve the weight energy density of the battery cell 10 and the battery 100; on the other hand, since the notch of the second receiving groove 12120 is formed on the electrode outer end surface 123, and the electrode outer end surface 123 is the surface of the first electrode 12 away from the active material coating portion 21, the second receiving groove 12120 can be open in the direction away from the active material coating portion 21. In this way, when at least a portion of the electrode ear 221 is accommodated in the second receiving groove 12120, the electrode ear 221 can be easily stored and sorted through the notch of the second receiving groove 12120, and the electrode ear 221 and the first electrode 12 can be easily welded through the notch of the second receiving groove 12120, thereby reducing the production difficulty of the battery cell 10 and improving the production efficiency of the battery cell 10.

[0401] Furthermore, since the welding of the pole ear portion 221 and the first pole 12 can be achieved from the outside of the shell 11, the first pole 12 can be arranged on the closed end of the shell body 111. In this way, when the battery cell 10 is used in a vibration environment, the amplitude of the connection between the shell body 111 and the shell cover 112 is small, and the connection position between the shell body 111 and the shell cover 112 is not easy to crack, which can improve the reliability of the battery cell 10 and can help reduce the wall thickness of the shell body 111, thereby reducing cost and weight, and helping to achieve miniaturization of the battery cell 10.

[0402] At the same time, since the second receiving tank 12120 can be connected to the interior of the shell 11 through the first perforation 12130, the second receiving tank 12120 can also serve as a buffer and temporary storage structure for the electrolyte, so that more electrolyte can be accommodated in the shell 11. Since the battery cell 10 will lose electrolyte during the charging and discharging process, when there is more electrolyte, the service life of the battery cell 10 can be extended; and because the second receiving tank 12120 can be connected to the interior of the shell 11 through the first perforation 12130, the second receiving tank 12120 can also serve as a receiving and buffer structure for gas production inside the battery cell assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

[0403] In combination with Figures 45 and 59, in some embodiments, the first pole 12 includes an integrally formed pole body, a first limit platform and a second limit platform, the pole body is passed through the mounting hole 113, the first limit platform and the second limit platform are arranged at both ends of the pole body along the axial direction of the mounting hole 113, and the first limit platform is limited and matched with the outer side of the shell body 111, and the second limit platform is limited and matched with the inner side of the shell body 111, so that the first pole 12 is riveted to the shell body 111.

[0404] It can be understood that the first limiting platform and the second limiting platform respectively extend along the radial direction of the mounting hole 113 to the radial outside of the peripheral wall of the mounting hole 113. The first limiting platform can limit the movement of the first pole 12 relative to the shell body 111 in the direction toward the inside of the shell body 111, and the second limiting platform can limit the movement of the first pole 12 relative to the shell body 111 in the direction toward the outside of the shell body 111, so that the first pole 12 can be easily and reliably installed in the mounting hole 113 through the first limiting platform and the second limiting platform, which is beneficial to the riveting of the first pole 12 and the shell body 111, and facilitates the assembly of the first pole 12 and the shell body 111. There is no need to use other connection methods between the body 111, which can facilitate the reliable connection of the first pole 12 and the shell body 111, which is beneficial to simplifying the structure of the shell assembly 1 and simplifying the assembly process of the shell assembly 1; at the same time, the pole body, the first limit platform and the second limit platform of the first pole 12 are formed in one piece, which can save parts and costs, and ensure the strength of the first pole 12, so that after the first pole 12 is matched with the shell 11, it is not easy to separate from the shell 11 due to vibration or external pulling during the charging and discharging process of the battery cell 10, nor is it easy to crack or be damaged due to vibration or external pulling, which can improve the stability and reliability of the battery cell 10.

[0405] 60 , in some embodiments, the dimension of the first pole 12 in the first direction is greater than the dimension of the pole 12 in the second direction, the first direction and the second direction are perpendicular, and both the first direction and the second direction are perpendicular to the axial direction of the mounting hole 113 .

[0406] On the plane formed by the first direction and the second direction, the orthographic projection shape of the first pole 12 can be non-circular, which is conducive to achieving good matching between the first pole 12 and the wall of the shell body 111 on which the first pole 12 is arranged in the first direction and the second direction. To a certain extent, the cross-sectional area of ​​the first pole 12 that can be arranged on the above-mentioned wall of the shell body 111 can be increased, which is conducive to increasing the flow area of ​​the first pole 12 within the limited arrangement area on the above-mentioned wall, improving the flow capacity of the first pole 12, and improving the heat diffusion capacity of the first pole 12, thereby helping to improve the charging speed of the battery cell 10 using the shell assembly 1.

[0407] In some embodiments, the first direction is the length direction of the cross section of the first pole 12 , and the second direction is the width direction of the cross section of the first pole 12 . In this case, the axial direction of the mounting hole 113 may refer to the height direction of the first pole 12 or the axial direction of the pole 12 .

[0408] In some embodiments, in a cross-section of the first pole 12, a dimension of the first pole 12 in the first direction is greater than three times a dimension of the first pole 12 in the second direction. The first direction, the second direction, and the axial direction of the mounting hole 113 are perpendicular to each other. This facilitates a good match between the first pole 12 and the wall of the housing 111 where the first pole 12 is located in the first and second directions, so that the first pole 12 fully utilizes the arrangement area of ​​the wall of the housing 111 where the first pole 12 is located, increases the cross-sectional area of ​​the first pole 12, and facilitates forming the first pole 12 into a "super-large pole structure", which facilitates further increasing the flow area, flow capacity, and heat dissipation capacity of the first pole 12.

[0409] 57 , in some embodiments of the present application, the housing 111 has a second wall portion 1113 and a third wall portion 1114 that are oppositely disposed, and each of the second wall portion 1113 and the third wall portion 1114 is provided with at least one first pole 12 .

[0410] The "second wall portion 1113 and the third wall portion 1114" may refer to the end walls of the housing 111 located on both sides of the third direction and extending in the first direction (see FIG. 57 ), or may refer to the end walls of the housing 111 located on both sides of the third direction and extending in the second direction. Furthermore, the second wall portion 1113 and the third wall portion 1114 may be provided with one first pole 12 or multiple first poles 12.

[0411] That is, the first pole 12 can be provided on two opposing sides of the shell 111 (see Figures 53-55). When first poles 12 are provided on opposite sides of the shell 111, the conductive portion 22 can extend from the active material coating portion 21 near the first pole 12 on each side. The conductive portion 22 cooperates with the first pole 12 on the adjacent side to connect with it, thereby improving the problem of the pole ear 221 being pulled by the first pole 12 on the same side, resulting in cracking of the connection between the pole ear 221 and the active material coating portion 21, thereby improving the reliability of the battery cell 10. It is worth noting that the first poles 12 on both sides can be the same or different, and the connection method between the first poles 12 on both sides and the conductive portion 22 can be the same or different, and there is no limitation here.

[0412] 58 , in some embodiments, the shell body 111 has a plurality of wall portions 1115 , a portion of the plurality of wall portions 1115 being a first set wall portion 1116 , the area of ​​the first set wall portion 1116 being greater than the area of ​​the remaining wall portions 1115 , and the first pole 12 being disposed on the first set wall portion 1116 .

[0413] The "first predetermined wall portion 1116" may refer to the largest wall portion among the multiple walls 1115. In other words, the first terminal 12 is riveted to the largest wall portion of the housing 111. Since the wall portion 1115 connected to the first terminal 12 has the largest area, riveting the first terminal 12 is easier, improving assembly efficiency and increasing the quality rate of the battery cell 10.

[0414] For example, in some optional embodiments of the present application, the first electrode 12 can be located on the top surface of the housing 111, etc. When the first electrode 12 is located on the top surface of the housing 111, the accommodating portion 121 can be used to hold electrolyte, thereby improving the cycle life of the battery cell 10. Furthermore, when the first electrode 12 is located on the top surface of the housing 111 and the bracket 3 is located at the bottom of the active material coating portion 21, the contact area between the bracket 3 and the active material coating portion 21 can be increased, reducing stress concentration issues and eliminating the need for other supporting structural components.

[0415] In some embodiments, the housing 111 has multiple walls 1115, at least one of which is a second predetermined wall. The pressure relief portion 16 is disposed on the second predetermined wall, and the first terminal 12 is disposed on the remaining walls 1115 except for the second predetermined wall. The specific configuration of the pressure relief portion 16 is not limited, and it may be, for example, an explosion-proof valve or a weakened portion, etc., and can be used to relieve pressure when the pressure within the battery cell 10 is high, thereby improving the reliability of the battery cell 10.

[0416] The first pole 12 and the pressure relief portion 16 are arranged on different wall portions 1115. When thermal runaway occurs in the battery cell 10, the discharged high-temperature medium will be discharged through the pressure relief portion 16 without coming into contact with the first pole 12. This can reduce the probability of fire caused by contact between the circuit in the battery and the high-temperature medium.

[0417] For example, the multiple walls 1115 may refer to the upper wall, left wall, right wall, front wall, and rear wall of the housing 111. The second set wall may refer to the upper wall, and the first pole 12 may be disposed on one or more of the left wall, right wall, front wall, and rear wall. Similarly, the second set wall 1117 may refer to one of the left wall, right wall, front wall, and rear wall, and the first pole 12 may be disposed on the other wall 1115. Referring to FIG. 56 , in some embodiments of the present application, the pressure relief portion 16 is disposed on the housing cover 112, and the pressure relief portion 16 and the housing cover 112 are integrally formed.

[0418] In the above solution, the integral molding of the pressure relief portion 16 and the shell cover 112 can reduce the number of parts of the battery cell 10, thereby reducing the number of welding steps between the pressure relief portion 16 and the shell body 111, that is, there is no step of connecting the pressure relief portion 16 after or before the shell cover 112 is connected to the shell body 111. In this way, the assembly efficiency of the battery cell 10 can be improved, the welding process cost can be reduced, the possibility of failure of the welding position can be reduced, and the reliability of the battery cell 10 can be improved.

[0419] Optionally, the pressure relief portion 16 and the shell cover 112 are integrally formed, which can mean that the shell cover is formed by notching, that is, the pressure relief portion 16 is a weak component on the shell cover 112, and under a certain pressure, the weak component can crack to release pressure. By notching the pressure relief portion 16 as a whole on the shell cover 112, the shell cover 112 is not prone to deformation during the process of forming the pressure relief portion 16. The molding process of the shell cover 112 is relatively simple, which can improve the quality rate of the battery cell 10 and reduce costs.

[0420] 4 and 59 , in some embodiments, the shell body 111 has multiple wall portions 1111 , at least one of the multiple wall portions 1111 is a first wall portion 1112 , the first pole 12 is riveted to the first wall portion 1112 , and the thickness of the first wall portion 1112 is greater than the thickness of the remaining wall portions 1111 .

[0421] The first wall portion 1112 serves as the shell wall connecting the first terminal 12. The thickness of the first wall portion 1112 is greater than that of the remaining wall portions 1111. This greater thickness of the first wall portion 1112 improves the overall strength of the shell 111, thereby enhancing the reliability of the battery cell 10 during daily use. Furthermore, the greater thickness of the first wall portion 1112 also enhances the reliability of the riveted connection to the first terminal 12, thereby increasing the quality rate of the battery cell 10.

[0422] On the premise of ensuring the reliability of the riveting of the first pole 12, the thickness of the first wall portion 1112 can be a conventional wall thickness, while the wall thickness of the remaining wall portions 1111 is thinned. In this way, the space inside the shell body 111 can be increased while the outer contour size of the shell body 111 is fixed, and a larger active material coating portion 21 can be placed, which is beneficial to improving the energy density of the battery cell 10.

[0423] With reference to Figure 3 , in some embodiments of the present application, the pressure relief portion 16 is disposed on the first wall portion 1112 . That is, the pressure relief portion 16 and the first terminal 12 can be located on the same side surface of the housing 111 . This facilitates processing and assembly. Alternatively, the pressure relief portion 16 and the first terminal 12 can be located on opposite sides of the housing 111 . This saves space, increases the volume of the first terminal 12 , and reduces the adverse effects of the pressure relief portion 16 on the first terminal 12 when releasing pressure.

[0424] With reference to Figures 51 and 56 , in some embodiments of the present application, the housing 111 includes a pressure relief portion 16, which is located on the housing cover 112. This facilitates processing and provides reliable pressure relief. It is worth noting that in this embodiment, the first terminal 12 can be located on either the housing 111 or the housing cover 112, without limitation. For example, the pressure relief portion 16 can be integrally formed with the housing cover 112, thereby facilitating processing, simplifying assembly, improving production efficiency, and reducing costs.

[0425] In some embodiments, a ratio of the thickness of the first wall portion 1112 to any of the remaining wall portions 1111 is d1, where 1<d1≤7.5.

[0426] The ratio d1 of the thickness of the first wall 1112 to the thickness of the remaining walls 1111 is not suitable if it is too small or too large. If d1 is less than 1, the thickness of the first wall 1112 cannot be greater than the thickness of the remaining walls 1111, and the support strength of the first tab 12 cannot be improved. If d1 is greater than 7.5, the ratio of the thickness of the first wall 1112 to the thickness of the remaining walls 1111 is relatively large, resulting in a large thickness of all the walls 1111. Moreover, although the excessive thickness of the first wall 1112 can meet the strength requirements, it is not conducive to reducing the weight of the battery cell 10. Therefore, the maximum value of d1 is 7.5. For example, d1 can be 1.2, 1.4, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, etc.

[0427] In some embodiments, 1<d1≤2.5. As previously mentioned, considering the thinness of the shell body 111 and how to increase the space inside the shell while keeping the outer dimensions of the shell body 111 fixed, while d1 being greater than 2.5 can ensure that the shell body 111 has better overall strength, it will sacrifice the space inside the shell, which is not conducive to improving the energy density of the battery cell 10. Therefore, by setting d1 to a range greater than 1 and less than or equal to 2.5, the strength of the shell body 111 can be taken into account. At the same time, under the premise of keeping the outer dimensions of the shell body 111 fixed, a relatively large space can be provided inside the shell body 111, which is conducive to increasing the size of the active material coating portion 21 and improving the energy density of the battery cell 10.

[0428] In some embodiments, as shown in Figures 51 and 59, the thickness of the first wall portion 1112 is e1, where 1.5mm≤e1≤2.5mm, and / or the thickness of the remaining wall portions 1111 except the first wall portion 1112 is e2, where 0.3mm≤e2≤0.6mm.

[0429] When the thickness of the first wall portion 1112 is greater than that of the remaining wall portions 1111, the thickness e1 of the first wall portion 1112 can be 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, etc. In other words, if e1 is less than 1.5 mm, the thickness of the first wall portion 1112 is relatively small, resulting in insufficient strength and difficulty in riveting the first terminal 12. If e1 is greater than 2.5 mm, the thickness of the first wall portion 1112 is too large, and the shell body 111 is relatively thick, resulting in increased cost. When the outer contour dimensions of the shell body 111 are fixed, the space within the shell body 111 is reduced, which in turn results in a relatively small size of the active material coating portion 21, reducing the energy density of the battery cell 10.

[0430] Alternatively, if the thickness of the first wall portion 1112 is greater than the thickness of the remaining wall portions 1111, the thickness e2 of the remaining wall portions 1111 excluding the first wall portion 1112 can be 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, etc. It can be understood that if e2 is less than 0.3 mm, the thickness of the remaining wall portions 1111 excluding the first wall portion 1112 is relatively small. Even if the first wall portion 1112 has relatively good strength, the insufficient strength of the remaining wall portions 1111 will result in insufficient strength of the housing 111 and easy damage. If e2 is greater than 0.6 mm, the thickness of the remaining wall portions 1111 excluding the first wall portion 1112 will be relatively large. While this will ensure strength, it will increase cost. Given the fixed outer dimensions of the housing 111, the space within the housing 111 will be reduced, which will in turn reduce the size of the active material coating portion 21 and reduce the energy density of the battery cell 10.

[0431] Of course, when the thickness of the first wall portion 1112 is greater than the thickness of the remaining wall portions 1111, it may be possible to simultaneously satisfy the following conditions: the thickness of the first wall portion 1112 is e1, wherein 1.5 mm ≤ e1 ≤ 2.5 mm, and the thickness of the remaining wall portions 1111 except the first wall portion 1112 is e2, wherein 0.3 mm ≤ e2 ≤ 0.6 mm.

[0432] In some embodiments, 1.8mm≤e1≤2.2mm. Specifically, e1 can be 1.8mm, 1.85mm, 1.9mm, 1.95mm, 2.0mm, 2.1mm, 2.2mm, etc. The value of e1 should satisfy a certain safety margin. If e1 is less than 1.8mm, although the first wall portion 1112 can meet the strength requirements, the thickness of the first wall portion 1112 is relatively small, resulting in increased processing or process costs, and the first wall portion 1112 is more susceptible to damage under extreme working conditions; if e1 is greater than 2.2mm, the first wall portion 1112 meets the strength requirements, but the use of more materials will also increase costs. When the outer contour dimensions of the shell body 111 are fixed, the internal space of the shell body 111 is relatively small, which will reduce the size of the active material coating portion 21 and reduce the energy density of the battery cell 10.

[0433] In some embodiments, 0.4mm≤e2≤0.55mm. Specifically, e2 can be 0.4mm, 0.42mm, 0.44mm, 0.46mm, 0.48mm, 0.5mm, 0.52mm, 0.55mm, etc. The value of e2 should satisfy a certain safety margin. If e2 is less than 0.4mm, although the remaining wall portions 1111 except the first wall portion 1112 can meet the strength requirements, the thickness of the remaining wall portions 1111 is relatively small, resulting in increased processing or process costs, and the remaining wall portions 1111 are more susceptible to damage under extreme working conditions; if e2 is greater than 0.55mm, while the remaining wall portions 1111 meet the strength requirements, the material used increases, resulting in increased costs. When the outer contour dimensions of the shell body 111 are fixed, the internal space of the shell body 111 is reduced, which in turn reduces the size of the active material coating portion 21 and reduces the energy density of the battery cell 10.

[0434] In some embodiments, the thickness of the shell cover 112 is less than the thickness of the first wall portion 1112. Since the first terminal 12 is riveted to the first wall portion 1112, and the shell cover 112 does not need to be connected to the first terminal 12, the strength requirement of the shell cover 112 is relatively low, and its thickness can be less than the thickness of the first wall portion 1112. This not only saves material, but also, when the outer contour dimensions of the shell 11 are fixed, the relatively small thickness of the shell cover 112 can increase the space within the shell 11. In this case, the shell 11 can accommodate a larger active material coating portion 21, which is beneficial to improving the energy density of the battery cell 10.

[0435] In some embodiments, the thickness of the housing cover 112 is greater than the thickness of the remaining wall portions 1111 excluding the first wall portion 1112 and adjacent to the housing cover 112 .

[0436] For example, the shell cover 112 may be welded to the shell body 111. In this embodiment, the thickness of the shell cover 112 may be greater than the thickness of the wall portion 1111 welded to the shell cover 112. Considering that the shell cover 112 needs to be sealed on the opening 111a and needs to provide appropriate strength, the shell cover 112 is set to have a thickness greater than the thickness of the remaining wall portions 1111 adjacent to the shell cover 112, excluding the first wall portion 1112. This improves the overall strength of the shell body 11 after the shell cover 112 is sealed on the opening 111a, thereby reducing the probability of damage to the shell body 11 and improving the reliability of the battery cell 10.

[0437] It should be noted that the thickness of the first wall portion 1112 mentioned above may refer to the average thickness of the main structure of the first wall portion 1112. For example, the first wall portion 1112 may be stepped, having multiple regions of varying thicknesses. In this case, the thickness of the first wall portion 1112 may refer to the thickness of the region riveted to the first pole 12. Similarly, the thickness of the housing cover 112 may refer to the average thickness of the main structure of the housing cover 112, and the thickness of the wall portion 1111 may refer to the average thickness of the main structure of the wall portion 1111.

[0438] 5 , in some embodiments, the thickness of the shell cover 112 is e3, where 1.0 mm ≤ e3 ≤ 1.5 mm. That is, if e3 is less than 1.0 mm, the shell cover 112 is relatively thin and insufficiently strong, resulting in a weak shell 11 and easy damage. If e1 is greater than 1.5 mm, the shell cover 112 is too thick, making the shell 111 thicker, increasing material consumption and leading to increased costs. Given the fixed outer dimensions of the shell 111, the space within the shell 111 is relatively small, which in turn reduces the size of the active material coating portion 21 and reduces the energy density of the battery cell 10.

[0439] In some embodiments, 1.2mm≤e3≤1.4mm. In other words, the value of e3 should satisfy a certain safety margin. If e3 is less than 1.2mm, the thickness of the shell cover 112 is relatively small. In this case, although the thickness of the shell cover 112 meets the strength requirements, the shell cover 112 is more likely to be damaged in accidents or during long-term operation. At the same time, a too small thickness of the shell cover 112 will also lead to higher processing requirements and increased costs. If e3 is greater than 1.4mm, while the thickness of the shell cover 112 meets the strength requirements, the shell cover 112 is relatively thick, which increases the material consumption and cost. With the outer contour dimensions of the shell body 111 fixed, the internal space of the shell body 111 is relatively small, thereby reducing the size of the active material coating portion 21 and reducing the energy density of the battery cell 10. By setting e3 within the range of greater than or equal to 1.2mm and less than or equal to 1.4mm, both strength requirements and volume requirements can be met.

[0440] 4 and 5 , in some embodiments, the opening 111 a is provided at the bottom of the housing 111 .

[0441] In the related art, the opening of the shell body is set at the top, and the shell cover is installed on the opening at the top of the shell body. When the shell body with this structure is processed, a processing chamfer is left at the bottom of the internal space of the shell body. When the active material coating part is installed into the shell, due to the existence of the processing chamfer, the bottom of the active material coating part (which may refer to the end of the active material coating part away from the conductive part) and the processing chamfer inside the shell body do not contact, and a certain space is left between the two. A partition will be set in this space to separate the active material coating part and the shell cover, which leads to waste of space inside the shell body. In the present application, since the opening 111a is provided at the bottom of the shell body 111 and the first electrode 12 is riveted to the shell body 111, in this shell 11 structure, when the active material coating portion 21 is inserted into the shell, there is no machined chamfer between the bottom of the active material coating portion 21 and the shell cover 112. Therefore, a partition can be omitted between the bottom of the active material coating portion 21 and the shell cover 112, thereby reducing the gap between the bottom of the active material coating portion 21 and the shell cover 112, increasing the size of the active material coating portion 21, and improving the energy density of the battery cell 10. Secondly, since there is no machined chamfer near the bottom of the active material coating portion 21, the active material coating portion 21 will not be damaged by contact with the machined chamfer. This reduces the probability of damage to the active material coating portion 21, reduces the loss of the active material coating, improves the performance of the battery cell 10, and also reduces stress concentration on the active material coating portion 21.

[0442] On the other hand, since the shell cover 112 is arranged at the bottom of the shell body 111, when the battery cells 10 are assembled into the battery 100, the bottom of the shell 11 generally needs to be fixed to the bottom of the case 20 of the battery 100. In this case, when vibration occurs during use, since the shell cover 112 is connected to the bottom of the case 20, the amplitude of the connection between the shell cover 112 and the shell body 111 is relatively small, which can further reduce the probability of cracking of the shell cover 112 and the shell body 111.

[0443] Please refer to Figure 5. In some embodiments, the active material coating portion 21 has a first end face 21a close to the shell cover 112. The battery cell 10 also includes an internal insulating member 4, which covers the battery cell assembly 2. At least a portion of the internal insulating member 4 is arranged between the first end face 21a and the shell cover 112. The internal insulating member 4 has a first surface 4a and a second surface 4b relative to each other. The first surface 4a contacts the first end face 21a, and the second surface 4b contacts the shell cover 112.

[0444] Referring to the description of the internal insulating part 4 in the previous text, the first surface 4a of the internal insulating part 4 is in contact with the first end face 21a, and the second surface 4b is in contact with the shell cover 112. While satisfying the insulation effect between the active material coating part 21 and the shell cover 112, it is possible to eliminate the need to set a partition between the active material coating part and the shell cover, which is beneficial for saving space in the shell body 111, increasing the size of the active material coating part 21, and further improving the energy density of the battery cell 10.

[0445] In some embodiments, as shown in FIG. 5 , the thickness of the portion of the inner insulating member 4 located between the first surface 4 a and the second surface 4 b is d2 , where 0< d2 ≤ 0.1 mm.

[0446] That is, d2 can be 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, etc. The thickness of the portion of the inner insulating member 4 located between the first surface 4a and the second surface 4b is greater than 0.1mm. While satisfying the insulation effect between the active material coating portion 21 and the shell cover 112, the thickness of the inner insulating member 4 is relatively large, which will occupy the space inside the shell body 111 and is not conducive to increasing the size of the active material coating portion 21. The thickness of the portion of the inner insulating member 4 located between the first surface 4a and the second surface 4b is less than 0.1mm. This can not only meet the insulation requirements between the active material coating portion 21 and the shell cover 112, but also save space, thereby facilitating the increase in the size of the active material coating portion 21 and further improving the energy density of the battery cell 10.

[0447] In some embodiments, 0.02 mm < d2 ≤ 0.05 mm. That is, d2 can be 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, 0.05 mm, etc.

[0448] In the above technical solution, the value of d2 should have a certain safety margin, that is, d2 needs to be selected in a suitable range. If d2 is greater than 0.05mm, its insulation effect may exceed the requirements between the active material coating part 21 and the shell cover 112, wasting the space inside the shell body 111; if d2 is less than 0.02mm, although the internal insulating part 4 can also meet the insulation requirements between the active material coating part 21 and the shell cover 112, due to the excessively small thickness, the manufacturing process difficulty of the internal insulating part 4 increases, which in turn leads to increased costs. It is easy to be damaged during the installation process, which increases the difficulty of assembly and reduces the product quality rate. Therefore, by setting d2 to a range greater than or equal to 0.02mm and less than or equal to 0.05mm, it can take into account the insulation requirements between the active material coating part 21 and the shell cover 112 while also taking into account the cost and assembly difficulty.

[0449] In some embodiments, as shown in FIG. 4 , the housing 111 has a first wall portion 1112 opposite to the housing cover 112 , and the first pole 12 is disposed on the first wall portion 1112 .

[0450] In this technical solution, the battery cell assembly 2 can enter through the opening 111 a , and the conductive portion 22 is directly opposite to the first pole 12 , so that the conductive portion 22 can be connected to the first pole 12 more easily, thereby improving the assembly efficiency of the battery cell 10 .

[0451] For example, the first wall portion 1112 and the shell cover 112 can be arranged at both ends of the third direction in Figure 3. As in the previous embodiment, the opening 111a is provided at the bottom of the shell body 111, and the shell cover 112 is provided at the bottom of the shell body 111. The battery cell assembly 2 can be installed into the shell body 111 from bottom to top along the third direction, so that the conductive portion 22 can be easily connected to the first pole 12.

[0452] 56 , in some embodiments of the present application, a liquid reservoir 112a is provided on the end surface of the shell cover 112 near the inner side of the shell body 111. The liquid reservoir 112a can be used to store electrolyte, increase the electrolyte content inside the battery cell 10, and thereby improve the cycle life of the battery cell 10.

[0453] 56 , in some embodiments of the present application, the liquid storage tank 112a includes a first groove portion 1121, which extends along the length of the housing cover 112. The extension direction of the first groove portion 1121 is consistent with the length direction of the housing cover 112, which can increase the volume of the first groove portion 1121 and store more electrolyte.

[0454] Referring to FIG. 56 , in some embodiments of the present application, the liquid storage tank 112a further includes a second slot portion 1122. The second slot portion 1122 is connected to the first slot portion 1121 and extends along the width of the housing cover 112. Adding the second slot portion 1122 to the first slot portion 1121 allows for further storage of electrolyte.

[0455] Referring to FIG. 56 , second grooves 1122 are optionally provided on both sides of the first groove 1121 in the longitudinal direction. By increasing the number of second grooves 1122, the capacity of the liquid reservoir 112a can be increased. For example, two second grooves 1122 are provided on each side of the first groove 1121 in the longitudinal direction. Of course, this is merely an example, and the number of second grooves 1122 is not limited thereto, and will not be further elaborated here.

[0456] Referring to Figure 56 , in some embodiments of the present application, the liquid storage tank 112a further includes a third slot 1123. The third slot 1123 is located at both ends of the first slot 1121 and points toward the corners of the housing cover 112. Adding the third slot 1123 to the first slot 1121 and the second slot 1122 further increases the storage capacity of the electrolyte.

[0457] Referring to FIG. 56 , third grooves 1123 are optionally provided on both sides of the first groove 1121 in the longitudinal direction. Increasing the number of third grooves 1123 can increase the capacity of the liquid reservoir 112a. For example, two third grooves 1123 may be provided on each side of the first groove 1121 in the longitudinal direction. This is merely an example, and the number of third grooves 1123 is not limited thereto, and will not be further elaborated here.

[0458] Please refer to FIG. 5 . In some embodiments of the present application, a protrusion 112 b is provided on the end surface of the shell cover 112 close to the inner side of the shell body 111 , and the circumferential end surface of the protrusion 112 b contacts the inner wall surface of the shell body 111 .

[0459] The “raised portion 112b” may refer to a structure protruding from the shell cover 112 . The raised portion 112b may include but is not limited to a boss structure and a ring-shaped runway structure, and may be specifically configured as needed.

[0460] In the above solution, the end face of the shell cover 112 close to the shell body 111 is in contact with the shell body 111, and the raised portion 112b is equivalent to being embedded in the inner wall surface of the shell body 111. In this way, the connection between the shell cover 112 and the shell body 111 can be made tighter and more reliable, and the connection between the shell cover 112 and the shell body 111 can be made stronger. At the same time, it is also beneficial to reduce the thickness of the shell cover 112, reduce the overall volume of the battery cell 10, and improve the battery energy density.

[0461] In some embodiments of the present application, a portion of the end surface of the housing cover 112 near the inner side of the housing body 111 is provided with a raised portion 112b, and the remaining portion is provided with a liquid reservoir 112a. For example, the raised portion 112b is rectangular, and the liquid reservoir 112a is located in the middle of the rectangular ring.

[0462] In some embodiments of the present application, the raised portion 112b may be constructed in a flat plate shape, with a step formed between it and the edge of the shell cover 112, and the liquid storage tank 112a is formed on the raised portion 112b (see FIG. 56 ).

[0463] In some embodiments of the present application, the shell cover 112 and the shell body 111 may be connected by welding or gluing.

[0464] According to some embodiments of the present application, the present application further provides a battery 100 , which includes the battery cell 10 of any of the above embodiments.

[0465] In the above technical solution, in the battery 100, since the first poles 12 of any adjacent battery cells 10 are connected to each other, when the battery 100 vibrates or deforms, the first poles 12 between any adjacent battery cells 10 will pull on each other. At this time, since the first poles 12 are arranged on the shell body 111, the force acting on the first poles 12 will be preferentially transmitted to the shell body 111, and will not directly act on the shell cover 112. On the one hand, the distance for the force to be transmitted to the connection position between the shell body 111 and the shell cover 112 can be extended. On the other hand, when subjected to force, the shell body 111 will preferentially deform to reduce the force at the connection position between the shell body 111 and the shell cover 112, effectively reducing the probability of cracking between the shell cover 111 and the shell body 112 during use of the battery 100, and improving the reliability of the battery cell 10.

[0466] According to some embodiments of the present application, the present application further provides an electric device 1000, which includes the battery cell 10 of any of the above embodiments; or includes the battery 100 of any of the above embodiments. The battery cell 10 or the battery 100 is used to provide power to the electric device 1000.

[0467] In the above technical solution, the electrical device 1000 uses the above-mentioned battery 100 or battery cell 10. During use, the probability of cracking between the shell cover 112 and the shell body 111 of the battery cell 10 is relatively low, which improves the reliability of the battery 100 and is conducive to improving the performance of the electrical device 1000.

[0468] Fourthly, an embodiment of the present application also provides an assembly method of a battery cell 10, wherein the battery cell 10 includes a shell assembly 1 and a cell assembly 2, wherein the shell assembly 1 includes a shell 11 and a first pole 12, the shell 11 includes a shell body 111 and a shell cover 112, and the cell assembly 2 includes an active material coating portion 21 and a conductive portion 22.

[0469] As shown in Figure 61, the assembly method includes: installing the battery cell assembly 2 into the shell body 111; overlapping the conductive part 22 with the first pole 12; welding the conductive part 22 to the first pole 12 from the outside of the shell body 111; and covering the shell cover 112 on the shell body 111.

[0470] It is understandable that when assembling the battery cell 10 of the present application, only the cell assembly 2 is inserted into the shell, which results in a relatively small number of parts to be inserted into the shell and a relatively light weight (in the related art, the cell assembly, shell cover, and pole need to be assembled first and then inserted into the shell together). Therefore, it is relatively easy to insert the cell assembly 2 into the shell, and it is also convenient for the conductive portion 22 to overlap with the first pole 12, resulting in relatively high assembly efficiency. Due to the limited internal space of the shell body 111, the conductive portion 22 is welded from the outside of the shell body 111 to the first pole 12 to facilitate welding operations and improve component assembly efficiency. Welding from the outside can effectively prevent metal foreign matter generated during welding from entering the interior of the battery cell, reducing the possibility of metal foreign matter causing internal short circuits in the battery cell. It also facilitates the cleaning of metal foreign matter generated during welding. Finally, the shell cover 112 is placed on the shell body 111 to complete the assembly.

[0471] Secondly, the assembly method of the present application only requires the steps of installing the battery cell assembly 2 into the shell body 111; overlapping the conductive portion 22 with the first pole 12; welding the conductive portion 22 to the first pole 12 from the outside of the shell body 111; and covering the shell cover 112 on the shell body 111 to complete the assembly of the battery cell 10. The overall assembly steps are relatively few, which can simplify the assembly process, reduce assembly time, and thus help reduce the manufacturing cost of the battery cell 10.

[0472] In some embodiments, as shown in Figure 62, the battery cell 10 also includes a bracket 3, and the edge of the bracket 3 has a shell entry guide surface 35. The step of installing the battery cell assembly 2 into the shell body 111 includes: installing the bracket 3 to the side of the active material coating portion 21 close to the first pole 12, so that the shell entry guide surface 35 is located on the side of the bracket 3 away from the active material coating portion 21; and installing the battery cell assembly 2 into the shell body 111 under the guidance of the shell entry guide surface 35.

[0473] In this technical solution, the bracket 3 and the cell assembly 2 can be pre-assembled together during assembly, and then this pre-assembled assembly is installed into the housing 11. During installation, the bracket 3 is located at the front end of the active material coating portion 21, that is, the bracket 3 enters the housing 11 before the active material coating portion 21. Therefore, the difficulty of the bracket 3 entering the housing 11 can be reduced by using the shell entry guide surface 35, and the bracket 3 is used to protect the active material coating portion 21, reducing the probability of scratching and damage between the active material coating portion 21 and the housing 11, thereby improving assembly efficiency and product quality. In addition, the contact area between the bracket 3 and the active material coating portion 21 can be increased, which can reduce stress concentration problems and eliminate other structural parts.

[0474] In some embodiments, as shown in FIG63 , the battery cell 10 further includes a bracket 3 having an avoidance hole 31 ; the step of overlapping the conductive portion 22 with the first pole 12 includes: passing the conductive portion 22 through the avoidance hole 31 ; overlapping the conductive portion 22 with the first pole 12 .

[0475] It can be understood that the use of the bracket 3 to separate the active material coating part 21 from the shell 11 is beneficial to improving the reliability of the battery cell 10, and the avoidance hole 31 is provided on the bracket 3, which can guide and constrain the conductive part 22 to cooperate with the first pole 12 by passing through the avoidance hole 31, so that during the assembly process of the battery cell 10, there is no need for the conductive part 22 to bypass the edge of the bracket 3 to approach the first pole 12, which not only simplifies the arrangement of the conductive part 22, saves the material of the conductive part 22, and reduces the cost, but also supports and guides the conductive part 22 to cooperate with the first pole 12 through the bracket 3, which can reduce the risk of short-circuiting between the conductive part 22 and the active material coating part 21, thereby further improving the reliability of the battery cell 10.

[0476] In some embodiments, as shown in Figure 64, the first pole 12 has a first receiving groove 12110, the surface of the first pole 12 facing the active material coating portion 21 is the pole inner end face 122, and the notch of the first receiving groove 12110 is formed on the pole inner end face 122; the step of overlapping the conductive portion 22 with the first pole 12 includes: extending the conductive portion 22 into the first receiving groove 12110; overlapping the conductive portion 22 with the groove wall of the first receiving groove 12110.

[0477] That is to say, in the process of overlapping the conductive part 22 with the first pole 12, since the first pole 12 has the first accommodating groove 12110, the conductive part 22 is relatively easy to be accurately positioned with the first pole 12. In this way, when the conductive part 22 is welded to the first pole 12 from the outside of the shell body 111, the stability of the conductive part 22 on the first pole 12 can be improved, the welding quality can be improved, and the performance of the battery cell 10 can be improved.

[0478] In some embodiments, as shown in Figure 65, the first pole 12 has a second accommodating groove 12120, the surface of the first pole 12 away from the active material coating part 21 is the pole outer end face 123, the notch of the second accommodating groove 12120 is formed on the pole outer end face 123, and the second accommodating groove 12120 is connected to the interior of the shell 11 through the first through-hole 12130; the step of overlapping the conductive part 22 with the first pole 12 includes: passing the conductive part 22 out of the first through-hole 12130 to be at least partially accommodated in the second accommodating groove 12120; overlapping the conductive part 22 with the groove wall of the second accommodating groove 12120 and / or the hole wall of the first through-hole 12130.

[0479] In the above technical solution, the second accommodating groove 12120 can make the overlapping portion of the conductive part 22 and the first pole 12 exposed on the outside of the shell 11, so that it is convenient to weld the conductive part 22 and the first pole 12 from the outside, the operation is relatively easy, and it is conducive to improving assembly efficiency.

[0480] In some embodiments, as shown in FIG. 66 , the battery cell 10 further includes a first cover plate 13 ; after welding the conductive portion 22 to the first pole 12 , the assembly method further includes: welding the first cover plate 13 to the first pole 12 to close the notch of the second accommodating groove 12120 .

[0481] In the above technical solution, by providing the first cover plate 13 to seal the notch of the second receiving tank 12120, leakage of the electrolyte within the housing 11 from the notch of the second receiving tank 12120 can be prevented. Furthermore, since the first cover plate 13 seals the notch of the second receiving tank 12120 and is electrically connected to the first terminal 12, the first cover plate 13 can be used to easily achieve indirect electrical connection between the first terminal 12 and the busbar component. This also helps increase the connection area of ​​the electrical connection, thereby helping to reduce the resistance of the electrical connection. Furthermore, the first cover plate 13 can separate the welded portion between the conductive portion 22 and the first terminal 12 from the welded portion between the first terminal 12 and the busbar component, reducing the impact of the welded portion between the conductive portion 22 and the first terminal 12 on the welded portion between the first terminal 12 and the busbar component, thereby improving the welding quality between the first terminal 12 and the busbar component.

[0482] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0483] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, wherein: include: A housing assembly (1) comprises a housing (11) and a first pole (12); the housing (11) comprises a housing body (111) and a housing cover (112); the housing body (111) has an opening (111a); the housing cover (112) covers the opening (111a); and the housing body (111) is provided with the first pole (12); A battery cell assembly (2) comprises an active material coating portion (21) and a conductive portion (22), wherein the active material coating portion (21) is accommodated in the shell body (111), and the conductive portion (22) electrically connects the active material coating portion (21) and the first pole (12).

2. The battery cell according to claim 1, wherein: The first pole (12) is provided with a receiving portion (121), and at least a portion of the conductive portion (22) is received in the receiving portion (121).

3. The battery cell according to claim 2, wherein: The accommodating portion (121) has a first accommodating groove (12110); the surface of the first pole (12) facing the active material coating portion (21) is the pole inner end face (122); a notch of the first accommodating groove (12110) is formed on the pole inner end face (122); and at least a portion of the conductive portion (22) is accommodated in the first accommodating groove (12110).

4. The battery cell according to claim 3, wherein: The housing (11) has a mounting hole (113), and the first pole (12) is mounted in the mounting hole (113); along the axial direction of the first pole (12), a depth H1 of the first accommodating groove (12110) is greater than or equal to a minimum distance H2 from an inner end surface (122) of the pole to the mounting hole (113).

5. The battery cell according to claim 3 or 4, wherein: The accommodating portion (121) comprises a first end wall (12111) and a first side wall (12113); the first end wall (12111) is located on a side of the first side wall (12113) away from the active material coating portion (21); the first end wall (12111) and the first side wall (12113) are arranged to form the first accommodating groove (12110); and the electrical connection position between the conductive portion (22) and the first pole (12) is located on the first end wall (12111) and / or the first side wall (12113).

6. The battery cell according to claim 5, wherein: The first end wall (12111) has a first recessed groove (12112), and at least part of the position where the conductive part (22) is electrically connected to the first end wall (12111) is located in the first recessed groove (12112).

7. The battery cell according to any one of claims 3 to 6, wherein: The first pole (12) has a first groove (126); a surface of the first pole (12) away from the active material coating portion (21) is a pole outer end surface (123); and a notch of the first groove (126) is formed on the pole outer end surface (123).

8. The battery cell according to claim 7, wherein: The housing assembly (1) further comprises a slot cover (7), wherein the slot cover (7) is arranged on the first pole (12) and covers the slot opening of the first groove (126).

9. The battery cell according to claim 2, wherein: The accommodating portion (121) has a second accommodating groove (12120); the surface of the first pole (12) away from the active material coating portion (21) is the pole outer end face (123); the notch of the second accommodating groove (12120) is formed on the pole outer end face (123); the second accommodating groove (12120) is connected to the interior of the shell (11) through a first through hole (12130); the conductive portion (22) is passed through the first through hole (12130) and is at least partially accommodated in the second accommodating groove (12120).

10. The battery cell according to claim 9, wherein: The electrical connection position between the conductive portion (22) and the first pole (12) is located on the hole wall of the first through hole (12130) formed by the accommodating portion (121).

11. The battery cell according to claim 9, wherein: The accommodating portion (121) comprises a second end wall (12121) and a second side wall (12123), wherein the second end wall (12121) is located on a side of the second side wall (12123) close to the active material coating portion (21), the second end wall (12121) and the second side wall (12123) are arranged to form the second accommodating groove (12120), the first through hole (12130) is opened on the second end wall (12121), and the electrical connection position between the conductive portion (22) and the first pole (12) is located on the second end wall (12121) and / or on the second side wall (12123).

12. The battery cell according to claim 11, wherein: The second end wall (12121) has a second recessed groove (12122), and at least part of the position where the conductive part (22) is electrically connected to the second end wall (12121) is located in the second recessed groove (12122).

13. The battery cell according to any one of claims 9 to 12, wherein: The housing (11) has a mounting hole (113), the first pole (12) is mounted in the mounting hole (113), and along the axial direction of the first pole (12), the depth H3 of the second accommodating groove (12120) is greater than or equal to the minimum distance H4 from the outer end surface (123) of the pole to the mounting hole (113).

14. The battery cell according to any one of claims 9 to 13, wherein: The housing assembly (1) further comprises a first cover plate (13), the first cover plate (13) cooperates with the first pole (12) and closes the notch of the second receiving groove (12120), and the first cover plate (13) is electrically connected to the first pole (12).

15. The battery cell according to claim 14, wherein: The first cover plate (13) comprises a first conductive member (131) and a second conductive member (132) made of different materials; the first conductive member (131) cooperates with and is electrically connected to the first pole (12); and the second conductive member (132) cooperates with and is electrically connected to the first conductive member (131).

16. The battery cell according to claim 15, wherein: The first conductive member (131) has a second groove (1311), and the second conductive member (132) is embedded in the second groove (1311). The notch of the second groove (1311) is formed on the surface of the first conductive member (131) away from the second accommodating groove (12120), so that the second conductive member (132) is exposed from the notch of the second groove (1311).

17. The battery cell according to any one of claims 14 to 16, wherein: The first cover plate (13) is embedded in the notch of the second receiving groove (12120).

18. The battery cell according to claim 17, wherein: The wall surface of the first pole (12) at the notch of the second receiving groove (12120) is a guiding inclined surface (12126), and the guiding inclined surface (12126) is used to guide the first cover plate (13) to cooperate with the notch of the second receiving groove (12120).

19. The battery cell according to claim 17 or 18, wherein: The second accommodating groove (12120) comprises a first groove section (12124) and a second groove section (12125) located on a side of the first groove section (12124) close to the outer end surface (123) of the pole, the cross-sectional area of ​​the second groove section (12125) being larger than the cross-sectional area of ​​the first groove section (12124) so ​​as to form a step surface (12127) between the first groove section (12124) and the second groove section (12125), and the first cover plate (13) is embedded in the second groove section (12125) and supported on the step surface (12127).

20. The battery cell according to any one of claims 2 to 19, wherein: The first pole (12) comprises a first pole portion (124) and a second pole portion (125) made of different materials and electrically connected, the second pole portion (125) being located on a side of the first pole portion (124) away from the active material coating portion (21), the accommodating portion (121) being arranged on the first pole portion (124) or on the first pole portion (124) and the second pole portion (125), and the conductive portion (22) being electrically connected to the first pole portion (124).

21. The battery cell according to claim 2, wherein: The accommodating portion (121) has a fourth accommodating groove (12150); the surface of the first pole (12) away from the active material coating portion (21) is the pole outer end face (123); the notch of the fourth accommodating groove (12150) is formed on the pole outer end face (123); the fourth accommodating groove (12150) is connected to the interior of the shell (11) through a second through hole (12160); the conductive portion (22) is penetrated through the second through hole (12160); and the electrical connection position between the conductive portion (22) and the first pole (12) is located on the hole wall of the second through hole (12160) formed in the accommodating portion (121).

22. The battery cell according to claim 2-8, 9-20 or 21, wherein: Also includes: A bracket (3) is located inside the housing (11) and on a side of the active material coating portion (21) close to the first pole (12); the bracket (3) has an avoidance hole (31) for avoiding the conductive portion (22); the conductive portion (22) is suitable for extending to a side of the bracket (3) away from the active material coating portion (21) through the avoidance hole (31).

23. The battery cell according to claim 22, wherein: The bracket (3) is provided with a guide portion (32), the guide portion (32) surrounds and forms at least a portion of the avoidance hole (31), and the guide portion (32) at least partially extends to the accommodating portion (121).

24. The battery cell according to any one of claims 23, wherein: The edge of the bracket (3) facing away from the shell cover (112) has a shell entry guide surface (35), and the shell entry guide surface (35) includes a curved surface and / or an inclined surface.

25. The battery cell according to any one of claims 22 to 24, wherein: The bracket (3) is an integrated structure; or, the bracket (3) is a split structure and comprises a detachable first bracket (33) and a second bracket (34), wherein the avoidance hole (31) is defined between the first bracket (33) and the second bracket (34).

26. The battery cell according to any one of claims 22 to 25, wherein: Also includes: An internal insulating member (4), the internal insulating member (4) is located inside the shell (11) and wrapped around the active material coating portion (21), and is connected to the bracket (3).

27. The battery cell according to any one of claims 1 to 26, wherein: The housing assembly (1) comprises at least one first pole (12) riveted to the housing body (111).

28. The battery cell according to claim 26, wherein: The shell body (111) is provided with a mounting hole (113); the first pole (12) comprises an integrally formed pole body, a first limiting platform and a second limiting platform; the pole body is passed through the mounting hole (113); the first limiting platform and the second limiting platform are arranged at two ends of the pole body along the axial direction of the mounting hole (113); the first limiting platform is limitedly matched with the outer side of the shell body (111); and the second limiting platform is limitedly matched with the inner side of the shell body (111), so that the first pole (12) is riveted to the shell body (111).

29. The battery cell according to claim 28, wherein: The size of the first pole (12) in a first direction is greater than the size of the first pole (12) in a second direction, the first direction is perpendicular to the second direction, and the first direction and the second direction are both perpendicular to the axial direction of the mounting hole (113).

30. The battery cell according to any one of claims 1 to 28, wherein: The shell body (111) has a second wall portion (1112) and a third wall portion (1113) which are arranged opposite to each other, and the second wall portion (1112) and the third wall portion (1113) are both provided with at least one of the first poles (12).

31. The battery cell according to any one of claims 1 to 28, wherein: The shell body (111) has a plurality of wall portions (1111), a portion of the plurality of wall portions (1111) is a first set wall portion (1116), an area of ​​the first set wall portion (1116) is larger than an area of ​​the remaining wall portions (1111), and the first pole (12) is arranged on the first set wall portion (1116).

32. The battery cell according to any one of claims 1 to 28, wherein: The shell body (111) has a plurality of wall portions (1111), at least one of the plurality of wall portions (1111) is a second set wall portion, the battery cell further comprises a pressure relief portion (16), the pressure relief portion (16) is arranged on the second set wall portion, and the first pole (12) is arranged on the remaining wall portions (1111) except the second set wall portion.

33. The battery cell according to any one of claims 1 to 32, wherein: The battery cell (10) further comprises a pressure relief portion (16), wherein the pressure relief portion (16) is arranged on the shell cover (112), and the pressure relief portion (16) and the shell cover (112) are integrally formed.

34. The battery cell according to any one of claims 1 to 32, wherein: The shell body (111) has a plurality of wall portions (1111), at least one of the plurality of wall portions (1111) is a first wall portion (1112), the first pole (12) is riveted to the first wall portion (1112), and the thickness of the first wall portion (1112) is greater than the thickness of the remaining wall portions (1111).

35. The battery cell according to claim 34, wherein: The thickness of the shell cover (112) is smaller than the thickness of the first wall portion (1112).

36. The battery cell according to claim 35, wherein: The thickness of the shell cover (112) is greater than the thickness of the remaining wall portions (1111) except the first wall portion (1112) and adjacent to the shell cover (112).

37. The battery cell according to any one of claims 1 to 36, wherein: The opening (111a) is arranged at the bottom of the shell body (111).

38. The battery cell according to claim 37, wherein: The active material coating portion (21) has a first end face (21a) close to the shell cover (112), and the battery cell also includes an internal insulating member (4), the internal insulating member (4) covers the battery cell assembly (2), at least part of the internal insulating member (4) is arranged between the first end face (21a) and the shell cover (112), and the internal insulating member (4) has a first surface (4a) and a second surface (4b) opposite to each other, the first surface (4a) is in contact with the first end face (21a), and the second surface (4b) is in contact with the shell cover (112).

39. The battery cell according to any one of claims 1 to 38, wherein: The housing (111) has a first wall portion (1112) opposite to the housing cover (112), and the first pole (12) is arranged on the first wall portion (1112).

40. A battery, wherein: The invention comprises a battery cell (10) according to any one of claims 1 to 39.

41. An electrical device, wherein: Comprising a battery cell (10) according to any one of Claims 1 to 39; or comprising a battery (100) according to Claim 40.

42. A method for assembling a battery cell, wherein: The battery cell (10) comprises a housing assembly (1) and a cell assembly (2), the housing assembly (1) comprising a housing (11) and a first pole (12), the housing (11) comprising a housing body (111) and a housing cover (112), the housing body (111) being provided with the first pole (12), and the cell assembly (2) comprising an active material coating portion (21) and a conductive portion (22); The assembly method comprises: Installing the battery core assembly (2) into the shell (111); Overlapping the conductive portion (22) with the first pole (12); Welding the conductive portion (22) to the first pole (12) from the outside of the shell body (111); The shell cover (112) is covered on the shell body (111).

43. The assembly method according to claim 42, wherein: The battery cell further comprises a bracket (3), the edge of the bracket (3) having a shell entry guide surface (35); The step of installing the battery cell assembly (2) into the shell (111) comprises: The bracket (3) is mounted on a side of the active material coating portion (21) close to the first pole (12), so that the shell entry guide surface (35) is located on a side of the bracket (3) away from the active material coating portion (21); The battery core assembly (2) is installed into the shell body (111) under the guidance of the shell entry guide surface (35).

44. The assembly method according to claim 42, wherein: The battery cell further comprises a bracket (3), wherein the bracket (3) has an avoidance hole (31); The step of overlapping the conductive portion (22) and the first pole (12) comprises: Passing the conductive portion (22) through the avoidance hole (31); The conductive portion (22) is overlapped with the first pole (12).

45. The assembly method according to claim 42, wherein: The first pole (12) has a first receiving groove (12110); the surface of the first pole (12) facing the active material coating portion (21) is a pole inner end surface (122); and a notch of the first receiving groove (12110) is formed on the pole inner end surface (122); The step of overlapping the conductive portion (22) with the first pole (12) comprises: Extending the conductive portion (22) into the first receiving groove (12110); The conductive portion (22) is overlapped with the groove wall of the first receiving groove (12110).

46. ​​The assembly method according to claim 42, wherein: The first pole (12) has a second receiving groove (12120); the surface of the first pole (12) away from the active material coating portion (21) is a pole outer end surface (123); a notch of the second receiving groove (12120) is formed on the pole outer end surface (123); and the second receiving groove (12120) is connected to the interior of the housing (11) through a first through hole (12130); The step of overlapping the conductive portion (22) with the first pole (12) comprises: Passing the conductive portion (22) through the first through hole (12130) to be at least partially accommodated in the second accommodation groove (12120); The conductive portion (22) is overlapped with the groove wall of the second receiving groove (12120) and / or the hole wall of the first through hole (12130).

47. The assembly method according to claim 46, wherein: The battery cell further comprises a first cover plate (13); After welding the conductive portion (22) to the first pole (12), the assembly method further comprises: The first cover plate (13) is welded to the first pole (12) to close the notch of the second receiving groove (12120).

Images