Battery monomer, battery and electric device

Abstract

The invention discloses a battery monomer, a battery and an electric device, and belongs to the technical field of batteries. The single battery comprises a shell assembly and a battery cell assembly, the shell assembly comprises a shell and a first pole arranged on the shell, the battery cell assembly comprises an active substance coating part and a conductive part, the active substance coating part is accommodated in the shell, the conductive part is used for electrically connecting the active substance coating part and the first pole, the first pole is provided with an accommodating part, and the accommodating part is used for accommodating the active substance coating part. And at least part of the conductive part is accommodated in the accommodating part. According to the battery monomer, at least part of the conductive part is accommodated in the accommodating part, so that the occupied space of the conductive part in the shell is reduced, and the energy density of the battery monomer is favorably improved.

Description

Battery cells, batteries and electrical devices Technical Field

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

[0002] New energy vehicles have experienced rapid growth in recent years. Batteries, as the power source of electric vehicles, play an irreplaceable and important role. Batteries typically consist of multiple cells, but the energy density of these cells is currently difficult to increase, hindering vehicle range.

[0003] Summary of the Invention

[0004] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which are beneficial to improving the energy density of the battery cell.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, which includes: a shell assembly and a cell assembly, the shell assembly includes a shell and a first pole arranged in the shell, the cell assembly includes an active material coating portion and a conductive portion, the active material coating portion is accommodated in the shell, and the conductive portion is used to electrically connect the active material coating portion and the first pole, wherein the first pole is provided with a accommodating portion, and at least part of the conductive portion is accommodated in the accommodating portion.

[0006] 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, so as to improve 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 electrode assembly, and thereby improve the working reliability and stability of the battery cell and the battery.

[0007] 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.

[0008] 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 the shell can accommodate It can hold more electrolyte. Since the electrolyte will be lost during the charge and discharge process of the battery cell, when there is more electrolyte, the service life of the battery cell can be extended. And because the first holding tank is facing the active material coating part, the first holding tank can also serve as a holding and buffer structure for the gas generated inside the electrode assembly, reducing the expansion of the battery cell and improving the reliability and stability of the battery cell. In addition, the first holding tank is located on the inner side of the pole, and external foreign matter and impurities are not easy to enter the first holding tank, thereby reducing the impact of external foreign matter and impurities on the electrode assembly, ensuring the stability and reliability of the electrode assembly, and thus improving the stability and reliability of the battery cell and the battery.

[0009] 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.

[0010] 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 electrode 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.

[0011] In some embodiments, the first pole 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 receiving 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.

[0012] In the above technical solution, by locating 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 electrically connects to the conductive portion. This simplifies the structure of the first terminal, facilitating its processing, and simplifies the structure of the conductive portion, reducing redundancy and cost. Furthermore, utilizing the walls of the first receiving groove to achieve electrical connection with the conductive portion allows for a relatively large area for electrical connection between the conductive portion and the first terminal, reducing the difficulty of electrical connection while also improving the reliability and stability of the electrical connection, thereby enhancing the performance of the battery cell.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] In some embodiments, the housing assembly further includes a slot cover, which is disposed on the pole and covers a slot opening of the first groove.

[0018] 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.

[0019] In some embodiments, the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a pole ear portion electrically connected to the current collector, the pole ear portion includes a plurality of pole ear sheets, the plurality of pole ear sheets converge at a position close to the current collector to form a first gathered portion, the plurality of pole ear sheets converge and connect at a position away from the current collector to form a second gathered portion, the first gathered portion connects the second gathered portion and the active material coating portion, and at least a portion of the second gathered portion is accommodated in the first accommodating groove.

[0020] In the above technical solution, since the pole ear portion includes a second gathered portion formed by converging and connecting multiple pole ear sheets, at least a portion of the second gathered portion is accommodated in the first accommodating groove, which facilitates the connection between the conductive portion and the first pole, can fully utilize the space of the first pole, and improve the volume energy density of the battery cell.

[0021] In some embodiments, at least a portion of the first gathered portion is received in the first receiving groove.

[0022] In the above technical solution, at least part of the first folded portion of the pole ear and at least part of the second folded portion are both accommodated in the first accommodating groove, so that the space in the first pole can be more fully utilized, further reducing the space occupied by the pole ear in the shell and improving the volume energy density of the battery cell.

[0023] In some embodiments, the conductive portion further includes an adapter plate, which is connected to the second retracted portion. The conductive portion is electrically connected to the first pole via the adapter plate, and at least a portion of the adapter plate is accommodated in the first accommodation groove.

[0024] In the above technical solution, on the one hand, by accommodating at least a portion of the second gathered portion and at least a portion of the adapter plate within the first receiving groove, the space within the first electrode can be more fully utilized, further reducing the space occupied by the conductive portion within the housing, thereby further improving the volumetric energy density of the battery cell. On the other hand, by using the adapter plate to achieve indirect electrical connection between the second gathered portion and the first electrode, the adapter plate can be welded to the first electrode at a location that avoids the second gathered portion. This weld between the adapter plate and the first electrode is highly reliable and less prone to weld cracking, further improving the reliability and stability of the battery cell. Furthermore, the use of the adapter plate to electrically connect the first electrode and the tab can also simplify the tab structure.

[0025] In some embodiments, the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a pole ear portion and a transition piece, the pole ear portion includes a plurality of pole ear pieces electrically connected to the current collector, the plurality of pole ear pieces converge at a position close to the current collector to form a first gathered portion, the plurality of pole ear pieces converge and connect at a position away from the current collector to form a second gathered portion, the transition piece is electrically connected to the second gathered portion, at least a portion of the transition piece is accommodated in the first accommodating groove, and is electrically connected to the first pole.

[0026] In the above technical solution, on the one hand, an indirect electrical connection between the second gathered portion and the first pole is achieved by adopting an adapter plate, and the adapter plate can be welded to the first pole at a position avoiding the second gathered portion. The welding reliability of the adapter plate and the first pole is good, and welding cracking problems are not likely to occur, and the reliability and stability of the battery cell can be further improved; at the same time, the first pole and the pole ear portion are electrically connected through the adapter plate, which can also simplify the structure of the pole ear portion; on the other hand, since at least part of the adapter plate is accommodated in the first accommodating groove, the adapter plate can occupy the space in the first pole, thereby reducing the space occupied by the adapter plate in the shell to accommodate a larger active material coating portion, thereby improving the volume energy density of the battery cell, and reducing the probability of short circuit between the adapter plate and the active material coating portion, reducing the risk of short circuit of the electrode assembly, and improving the stability and reliability of the battery cell.

[0027] 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.

[0028] 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 electrolyte will be consumed during the charging and discharging process of the battery cell, 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 receiving and buffer structure for gas production inside the electrode assembly, reducing the expansion of the battery cell and improving the reliability and stability of the battery cell.

[0029] 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 by the first pole.

[0030] 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.

[0031] In some embodiments, the first pole includes a second end wall and a second side wall, the second end wall is located on the 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 in 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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 electrode 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] In some embodiments, the first cover plate is embedded in the notch of the second receiving groove.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] In some embodiments, the first cover plate has a stress relief groove, and the stress relief groove is located in the outer peripheral area of ​​the first cover plate.

[0050] In the above technical solution, by setting a stress relief groove on the first cover plate, the stress generated during the first cover plate's own processing or during the electrical connection between the first cover plate and the first pole can be released, thereby improving the problem of deformation or damage of the first cover plate caused by stress.

[0051] In some embodiments, the housing assembly further includes a second cover plate, which covers the first through-hole and the conductive portion located in the second receiving groove.

[0052] In the above technical solution, when the electrolyte enters the second containing tank from the first through-hole, the second cover plate can improve the problem of the electrolyte overflowing from the first pole, thereby improving the reliability of the battery cell.

[0053] 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.

[0054] 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.

[0055] In some embodiments, the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a pole ear portion electrically connected to the current collector, the pole ear portion includes a plurality of pole ear sheets, the plurality of pole ear sheets converge at a position close to the current collector to form a first gathered portion, the plurality of pole ear sheets converge and connect at a position away from the current collector to form a second gathered portion, the first gathered portion connects the second gathered portion and the active material coating portion, and at least a portion of the second gathered portion is accommodated in the second accommodating groove.

[0056] In the above technical solution, since the pole lug portion includes a second gathered portion formed by converging and connecting a plurality of pole lug sheets, at least a portion of the second gathered portion is accommodated in the second accommodating groove, which facilitates assembly of the conductive portion and the first pole.

[0057] In some embodiments, the accommodating portion further has a third accommodating groove, the surface of the first pole facing the active material coating portion is the inner end face of the pole, the third accommodating groove is located on the side of the second accommodating groove close to the active material coating portion, and the notch of the third accommodating groove is formed on the inner end face of the pole, the third accommodating groove is connected to the second accommodating groove through a first through-hole, and at least part of the first folded portion is accommodated in the third accommodating groove.

[0058] In the above technical solution, at least part of the first folded portion of the pole lug is accommodated in the third accommodating groove, and at least part of the second folded portion is accommodated in the second accommodating groove, thereby further fully utilizing the space in the first pole.

[0059] In some embodiments, the conductive portion further includes an adapter plate, which is connected to the second retracted portion. The conductive portion is electrically connected to the first pole via the adapter plate, and at least a portion of the adapter plate is accommodated in the second accommodation groove.

[0060] In the above technical solution, by accommodating at least a portion of the second gathered portion and at least a portion of the adapter plate within the second receiving groove, the space within the first electrode can be more fully utilized, further reducing the space occupied by the conductive portion within the housing, thereby further improving the volumetric energy density of the battery cell. Furthermore, by using the adapter plate to achieve indirect electrical connection between the second gathered portion and the first electrode, the adapter plate can be welded to the first electrode at a location that avoids the second gathered portion. This provides a strong weld between the adapter plate and the first electrode, making weld cracking less likely, and further improving the reliability and stability of the battery cell. Furthermore, by using the adapter plate to achieve electrical connection between the tab portion and the first electrode, the tab portion structure can be simplified.

[0061] In some embodiments, the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a pole ear portion and a transition piece, the pole ear portion includes a plurality of pole ear pieces electrically connected to the current collector, the plurality of pole ear pieces converge at a position close to the current collector to form a first gathered portion, the plurality of pole ear pieces converge and connect at a position away from the current collector to form a second gathered portion, the transition piece is electrically connected to the second gathered portion, at least a portion of the transition piece is accommodated in the second accommodating groove, and is electrically connected to the first pole.

[0062] In the above technical solution, the conductive part includes an adapter plate for realizing electrical connection between the pole ear part and the first pole, thereby simplifying the structure of the pole ear part, and by accommodating at least part of the adapter plate in the second accommodating groove, the adapter plate can occupy the space in the first pole, thereby reducing the space occupied by the adapter plate in the shell to accommodate a larger active material coating part, thereby improving the energy density of the battery cell, and reducing the probability of short circuit between the adapter plate and the active material coating part.

[0063] 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 through-hole, the conductive portion is passed through the second through-hole, and the electrical connection position between the conductive portion and the first pole is located on the hole wall of the second through-hole formed by the first pole.

[0064] 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.

[0065] 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.

[0066] In the above technical solution, by arranging an avoidance hole on the bracket, the conductive part can be guided and constrained to pass through the avoidance hole to cooperate with the first pole. This 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 through 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.

[0067] 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.

[0068] 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.

[0069] In some embodiments, a third groove is provided on the bracket, and at least a portion of the first pole located in the housing is accommodated in the third groove.

[0070] In the above technical solution, by providing a third groove on the bracket to accommodate at least part of the portion of the first pole located in the shell, on the one hand, it is beneficial to reduce the space occupied by the bracket in the shell, and on the other hand, it is also beneficial to improve the stability and reliability of the first pole, so as to ensure the reliability and stability of the electrical connection between the first pole and the battery cell assembly, so as to improve the reliability and stability of the battery cell charging and discharging operations.

[0071] In some embodiments, the avoidance hole includes a first hole segment and a second hole segment, the second hole segment is located on the side of the first hole segment close to the active material coating portion, and the cross-sectional area of ​​the second hole segment gradually increases along the direction away from the first hole segment, the active material coating portion includes a current collector and an active material layer provided on the current collector, the conductive portion includes a pole ear portion electrically connected to the current collector, the pole ear portion includes a plurality of pole ear sheets, the plurality of pole ear sheets converge at a position close to the current collector to form a first gathering portion, the plurality of pole ear sheets converge and are connected at a position away from the current collector to form a second gathering portion, the first gathering portion connects the second gathering portion and the active material coating portion, at least part of the first gathering portion is accommodated in the second hole segment, and the second gathering portion passes through the first hole segment.

[0072] In the above technical solution, by setting the avoidance hole to include a second hole segment that gradually expands in the direction of the active material coating portion, it is convenient for the second hole segment to accommodate more first folded portions, thereby improving the compactness of the fit between the bracket and the battery cell assembly, so that the overall volume of the battery cell is smaller, and the battery can accommodate a larger number of battery cells, thereby improving the volume energy density of the battery.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] In some embodiments, the housing assembly includes a plurality of poles, and at least one pole is a first pole.

[0078] In the above technical solution, at least one of all the poles of the shell assembly is a first pole, so that a part of the entire battery cell can be a first pole with an accommodating portion, or all of the poles can be first poles with an accommodating portion, so that they can be flexibly selected and matched according to actual needs such as energy density and cost to improve the applicability of the battery cell.

[0079] In some embodiments, the housing has a pressure relief portion, and the pressure relief portion and the pole are located on the same side surface of the housing; or, the pressure relief portion and the pole are located on two surfaces on different sides of the housing.

[0080] In the above technical solution, when the pole and the pressure relief part are arranged on the same side, processing and assembly are facilitated; and when the pole and the pressure relief part are arranged on different sides, space can be saved, the volume of the pole can be increased, and the adverse effects of the pressure relief part on the pole when releasing pressure can be reduced.

[0081] In some embodiments, the shell has a pressure relief portion, and the shell includes a shell body and a shell cover. One end of the shell body is open, the shell cover is arranged at the open end of the shell body, and the pressure relief portion is arranged on the shell cover.

[0082] In the above technical solution, the pressure relief part is easy to process and has good pressure relief reliability.

[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, since the battery is provided with the above-mentioned battery cell and since the first pole of the battery cell is provided with a receiving portion, the weight of the first pole can be reduced 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 pole, it is beneficial to improve the volume energy density of the battery cell, or reduce the space occupied by the battery cell itself, so that the battery of the same volume can accommodate a larger number of battery cells, which is beneficial to improve 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, and thus improve the working reliability and stability of the battery cell and the battery.

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

[0086] In the above technical solution, since the electrical device is provided with the above-mentioned battery, the energy density of the battery can be improved, which is beneficial to increasing the service life of the electrical device; and since the working reliability and stability of the battery can be improved, the working reliability and stability of the electrical device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] 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.

[0088] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0089] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0090] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0091] FIG4 is an orthographic view of a battery cell provided in some embodiments of the present application;

[0092] FIG5 is a cross-sectional view along line AA in FIG4 ;

[0093] FIG6 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0094] FIG7 is an assembly diagram of a second pole, a cell assembly, and a housing provided in some embodiments of the present application;

[0095] FIG8 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0096] FIG9 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0097] FIG10 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0098] FIG11 is a partial cross-sectional schematic diagram of a battery cell assembly provided in some embodiments of the present application;

[0099] FIG12 is a diagram illustrating various tab folding schemes for battery cell assemblies provided in some embodiments of the present application;

[0100] FIG13 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0101] FIG14 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0102] FIG15 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0103] FIG16 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0104] FIG17 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0105] FIG18 is a partial enlarged view of point B in FIG3 ;

[0106] FIG19 is an orthographic projection view of various first poles provided in some embodiments of the present application;

[0107] FIG20 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0108] FIG21 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0109] FIG22 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0110] FIG23 is an exploded view of the structure of a battery cell provided by some embodiments of the present application;

[0111] FIG24 is a partial cross-sectional schematic diagram of a housing assembly provided in some embodiments of the present application;

[0112] FIG25 is an exploded view of the structure of the housing assembly shown in FIG24;

[0113] FIG26 is an exploded view of the structure of the first cover plate shown in FIG25 ;

[0114] FIG27 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0115] FIG28 is an exploded view of the structure of the battery cell shown in FIG27;

[0116] FIG29 is a partial cross-sectional schematic diagram of a battery cell provided by some embodiments of the present application;

[0117] FIG30 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0118] FIG31 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0119] FIG32 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0120] FIG33 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0121] FIG34 is a schematic diagram of the cooperation between a battery cell assembly and a bracket provided in some embodiments of the present application;

[0122] FIG35 is a cross-sectional view taken along line CC in FIG34;

[0123] FIG36 is a schematic structural diagram of an integrated bracket provided in some embodiments of the present application;

[0124] FIG37 is a schematic structural diagram of a split bracket provided in some embodiments of the present application;

[0125] FIG38 is a partial cross-sectional schematic diagram of a battery cell assembly and a bracket provided in some embodiments of the present application;

[0126] FIG39 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;

[0127] FIG40 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;

[0128] FIG41 is an assembly diagram of the first pole, housing, and sealing gasket shown in FIG40 ;

[0129] FIG42 is a schematic structural diagram of a first pole provided in some embodiments of the present application;

[0130] FIG43 is an assembly diagram of a first pole, a housing, and a sealing gasket provided in some embodiments of the present application;

[0131] FIG44 is an exploded view of the structure of the first pole shown in FIG43;

[0132] FIG45 is an orthographic view of a battery cell provided by some embodiments of the present application;

[0133] FIG46 is an orthographic view of a battery cell provided by some embodiments of the present application;

[0134] FIG47 is a cross-sectional view taken along line DD in FIG46;

[0135] FIG48 is a schematic cross-sectional view of a housing assembly provided in some embodiments of the present application;

[0136] FIG49 is a schematic cross-sectional view of a housing assembly provided in some embodiments of the present application;

[0137] FIG50 is an orthographic view of a battery cell provided by some embodiments of the present application;

[0138] FIG51 is a cross-sectional view taken along line EE in FIG50;

[0139] FIG52 is a partial cross-sectional schematic diagram of a battery cell provided in some embodiments of the present application;

[0140] Figure 53 is a schematic structural diagram of the shell cover provided in some embodiments of the present application.

[0141] Icons: Electrical 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 body 111; Housing cover 112; Mounting hole 113; First pole 12; Receiving portion 121; First receiving groove 12110; First end wall 12111; First recessed groove 12112; First side wall 12113; Second receiving groove 12120; Second end wall 12121; Second recessed groove 12122; Second side wall 12123; First groove section 12124; Second groove section 12125; Guide slope 12126; Step 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; perforation portion 1282; flange 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 pole 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; current collector 211; active material layer 212; conductive portion 22; Pole ear portion 221; pole ear piece 2211; first retracted portion 2212; second retracted portion 2213; adapter plate 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; main body portion 36; extension portion 37; third groove 38; positioning groove 39; inner insulator 4; main body portion 41; connecting portion 42; seal 6; slot cover 7. DETAILED DESCRIPTION

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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.

[0146] In the embodiments of this application, identical reference numerals denote identical components, and for the sake of brevity, detailed descriptions of identical components across different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of 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 do not constitute any limitation on this application.

[0147] The term "plurality" used in this application refers to two or more (including two).

[0148] 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.

[0149] The battery referred to 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 referred to in this application may be a battery module or battery pack. A battery module generally includes multiple battery cells. A battery pack generally includes a casing for enclosing one or more battery cells or one or more battery modules. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0150] For example, a battery cell typically includes a housing, a cell assembly, and an electrolyte. The housing is used to house the cell assembly and electrolyte, and is provided with at least one positive electrode post and at least one negative electrode post. The cell assembly includes one or more electrode assemblies, which are formed by stacking or winding positive and negative electrode sheets and separators.

[0151] The positive electrode sheet generally includes 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 a positive electrode tab. Multiple positive electrode tabs are stacked together and electrically connected to the positive electrode column. For example, the stacked multiple positive electrode tabs can be directly welded to the positive electrode column to form an electrical connection; alternatively, the battery cell assembly may further include a positive electrode adapter. The stacked multiple positive electrode tabs are welded to one end of the positive electrode adapter, and the other end of the positive electrode adapter is welded to the positive electrode column to form an electrical connection between the positive electrode tab and the positive electrode column.

[0152] The negative electrode sheet can generally include 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 a negative electrode tab. Multiple negative electrode tabs are stacked together and electrically connected to the negative electrode column. For example, the multiple stacked negative electrode tabs can be directly welded to the negative electrode column to form an electrical connection; alternatively, the battery cell assembly can further include a negative electrode adapter. The multiple stacked negative electrode tabs are welded to one end of the negative electrode adapter, and the other end of the negative electrode adapter is welded to the negative electrode column to form an electrical connection between the negative electrode tab and the negative electrode column. The material of the separator is not limited, and can be, for example, polypropylene or polyethylene.

[0153] Battery cells operate primarily through the movement of metal ions between the positive and negative electrodes. For example, in lithium-ion batteries, the positive current collector can be made of aluminum, and the positive active material layer can be made of materials such as 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 materials such as carbon or silicon. During the charge and discharge process, lithium ions (Li+) intercalate and deintercalate between the two electrodes. During charging, Li+ deintercalates from the positive electrode and then intercalates into the negative electrode through the electrolyte, leaving the negative electrode in a lithium-rich state. The reverse occurs during discharge.

[0154] 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.

[0155] 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 an active material coating portion) and a current collector not coated with an active material layer (referred to as a pole tab piece). The positive and negative pole pieces and the separator are then stacked or wound in sequence to obtain an electrode assembly. In the electrode assembly, multiple pole tab pieces are stacked to form a pole tab portion. A pole post is provided on the shell of the battery cell, and the surface of the pole post facing the active material coating portion is the inner end face of the pole post. During the manufacturing of the battery cell, the pole tab portion is usually welded directly to the inner end face of the pole post, or indirectly welded to the inner end face of the pole post through a transition piece to ensure the normal charging and discharging operations.

[0156] However, the inventors discovered that when a battery cell adopts the above-mentioned structure, the tabs and adapter plates are stacked between the active material coating and the inner end face of the terminal column, occupying a large space. This prevents the active material coating from being increased within a given housing size, making it difficult to increase the energy density of the battery cell. Furthermore, due to design or manufacturing reasons, the tabs are typically long. When the space between the active material coating and the inner end face of the terminal column is small, the tabs become redundant after the electrode assembly is inserted into the housing. This can easily lead to short circuits between the tabs or adapter plates and the active material coating, compromising the reliability and stability of the battery cell.

[0157] Based on the above considerations, in order to improve the energy density, reliability and stability of the battery cell, the inventor has designed a battery cell after in-depth research, in which at least one of the poles of the battery cell is provided with a receiving portion, and at least a portion of the pole ear or adapter plate that does not have active material and plays a conductive role is accommodated in the receiving portion to reduce the space occupied by this portion in the shell, so that more space can be saved in the shell to accommodate the active material coating part, so that the volume of the active material coating part can be increased, which is beneficial to improving the energy density of the battery cell, and can reduce the redundancy of the pole ear or adapter plate in the shell to at least a certain extent, reduce the probability of short circuit between the pole ear or adapter plate and the active material coating part, thereby reducing the probability of occurrence of some reliability-related problems caused by short circuit, and thus improving the working reliability and stability of the battery cell.

[0158] 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.

[0159] For the convenience of description, the following embodiments take a vehicle as an example of an electrical device to introduce in detail the structures of the electrical device 1000 , the battery 100 and the battery cell 10 of the present application.

[0160] Please refer to Figure 1, which is a schematic structural diagram of a vehicle in which the power-consuming device 1000 provided in some embodiments of the present application is a vehicle. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The vehicle is provided with a battery 100, and the battery 100 can be arranged 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 be used as an operating power source for 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.

[0161] 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, with the first box body 201 covering 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; alternatively, the first box body 201 and the second box body 202 can both be hollow structures with one end open (for example, as shown in FIG. 2 ), with the open side of the first box body 201 covering 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 have various shapes, such as a cylinder or a rectangular parallelepiped.

[0162] In the battery 100, multiple battery cells 10 can be connected in series, in parallel, or in a hybrid connection. A hybrid connection 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 connection, and then the entire battery cell 10 can be 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 connection to form a battery module. The multiple battery modules are then connected in series, in parallel, or in a hybrid connection to form an entire battery cell, and then housed within the housing 20. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 10.

[0163] 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 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 first direction Z, the second direction X, and the third direction Y are perpendicular to each other. 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.

[0164] Please refer to Figures 4 and 5. Figure 4 is a front projection view of the battery cell 10 provided in some embodiments of the present application; Figure 5 is a cross-sectional view along line AA in Figure 4. In the embodiments of the present application, the battery cell 10 includes a shell assembly 1 and a cell assembly 2. The shell assembly 1 includes a shell 11 and a first pole 12 arranged on the shell 11.

[0165] The shape of the shell 11 is adjusted according to the type of battery cell 10, and the type of battery cell 10 in the embodiments of the present application is not limited. For example, when the battery cell 10 is a square battery, the shell 11 is square. When the battery cell 10 is a cylindrical battery, the shell 11 is cylindrical. The embodiments of the present application are all described by taking the shell 11 as an example. The shell 11 is provided with a pole, which is used to electrically connect to the battery cell assembly 2 to ensure the normal charging and discharging operation of the battery cell 10. Generally, the number of poles is at least two, specifically at least one positive pole and at least one negative pole. For example, when the number of poles is two, 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 the number of poles is four, two can be positive poles and two can be negative poles. In this case, both positive poles are electrically connected to the positive output position of the battery cell assembly 2, and both negative poles are electrically connected to the negative output position of the battery cell assembly 2.

[0166] At the same time, Figure 6 is a schematic structural diagram of a battery cell 10 provided in some embodiments of the present application; Figure 7 is an assembly diagram of a second pole 15, a cell assembly 2, and a housing 11 provided in some embodiments of the present application. Please refer to Figures 1 to 7. In the embodiments of the present application, at least one pole among the multiple poles is a first pole 12. The first pole 12 can serve as either a positive pole or a negative pole. The first pole 12 is a pole formed with a receiving portion 121. The receiving portion 121 is a virtual structure with a receiving space, which can be a groove-shaped structure, a hole-shaped structure, or a composite structure of a groove-shaped structure and a hole-shaped structure. In other words, all poles on the housing 11 can be first poles 12 formed with receiving portions 121, or a portion of the poles on the housing 11 can be first poles 12 formed with receiving portions 121. When a portion of the poles on the housing 11 are first poles 12 formed with receiving portions 121, the remaining poles on the housing 11 are second poles 15 without receiving portions 121 (see Figures 6 and 7).

[0167] Regardless of whether the pole on the shell 11 is the first pole 12 or the second pole 15, the first pole 12 and the second pole 15 can be electrically connected to the battery cell assembly 2 to ensure the normal charging and discharging process of the battery cell 10. Of course, in other embodiments of the present application, the shell assembly 1 can also be provided with only one pole, and it is the first pole 12. The first pole 12 includes two parts, which are insulated and connected, and can be used as the positive pole and the negative pole respectively. To simplify the description, the following mainly introduces the case where all the poles on the shell 11 are the first pole 12 formed with the accommodating portion 121.

[0168] Please refer to Figures 3 to 7 again. In the 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 both the first pole 12 and the second pole 15 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.

[0169] It should be noted that in the embodiments of the present application, 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, and 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 and the positive electrode post, and the negative electrode conductive portion electrically connects the negative electrode active material coating portion and the negative electrode post.

[0170] In the embodiment of the present application, referring again to Figures 4 and 5 , at least a portion of the conductive portion 22 is accommodated within the corresponding accommodating portion 121. "At least a portion" means that the conductive portion 22 may be entirely accommodated within the accommodating portion 121, or only a portion of the conductive portion 22 may be accommodated within the accommodating portion 121. Since the first electrode 12 is provided with the accommodating portion 121, the hollow structure of the accommodating portion 121 can reduce the weight of the electrode 12 to a certain extent, thereby increasing the weight energy density of the battery cell 10 and the battery 100.

[0171] 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.

[0172] Furthermore, by accommodating at least a portion of the conductive portion 22 within the accommodating portion 121, the space occupied by the battery cell 10 itself can be reduced, allowing a battery 100 of the same volume to accommodate a greater number of battery cells 10, thereby increasing the volumetric energy density of the battery 100. Furthermore, by accommodating at least a portion of the conductive portion 22 within the accommodating portion 121, thereby occupying the space within the first terminal 12, the redundancy of the conductive portion 22 within the housing 11 can be reduced to at least some extent, reducing the probability of short circuits between the conductive portion 22 and the active material coating portion 21, reducing the probability of short circuits in the battery cell 10, and improving the operational reliability and stability of the battery cell 10 and the battery 100. Furthermore, accommodating at least a portion of the conductive portion 22 within the accommodating portion 121 also facilitates stabilizing and positioning the conductive portion 22, thereby increasing the stability of the conductive portion 22 and facilitating welding of the conductive portion 22 to the first terminal 12, thereby improving assembly efficiency.

[0173] In some optional embodiments of the present application, please refer to Figures 3 to 5 again. 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.

[0174] In some other optional embodiments of the present application, please refer to Figures 6 and 7, at least one of the multiple poles on the shell assembly 1 is a first pole 12 with 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.

[0175] It should be noted that, referring to Figures 6 and 7, when the housing 11 is provided with a second pole 15, a relief groove 18 can be provided between the second pole 15 and the housing 11 as required, so that at least a portion of the conductive portion 22 is accommodated 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, which is conducive to improving energy density and improving problems such as short circuits caused by redundant conductive portions 22.

[0176] In the embodiments 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, FIG8 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application; FIG9 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application. Referring to FIG8 and FIG9 , 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 includes 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. The 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.

[0177] Exemplarily, the first receiving groove 12110 is a groove body, which is a groove-like structure with a certain depth. For example, when the first terminal 12 is disposed on the upper end wall of the housing 11 and the terminal inner end surface 122 is the lower surface of the first terminal 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 terminal 12 is disposed on the lower end wall of the housing 11 and the terminal inner end surface 122 is the upper surface of the first terminal 12, the first receiving groove 12110 is formed as a receiving groove with a groove opening open upward and the groove wall recessed downward.

[0178] 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.

[0179] 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.

[0180] 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, and improving the stability and reliability of the battery cell assembly 2, thereby improving the stability and reliability of the battery cell 10 and the battery 100.

[0181] Referring again to FIG. 8 , 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 to facilitate the first pole 12 to be mounted to the housing 11 through the mounting hole 113, and this is not limited here. At the same time, the first receiving groove 12110 can be arranged corresponding to the position of the mounting hole 113, or in other words, on a projection plane perpendicular to the axial direction R of the first pole 12, the orthographic projection of the first receiving groove 12110 is located within the orthographic projection range of the mounting hole 113. This allows the first receiving groove 12110 to have a greater depth to accommodate more conductive portions 22, thereby significantly reducing the space occupied by the conductive portions 22 within the housing 11.

[0182] Specifically, when the housing 11 is provided with a mounting hole 113 and the first pole 12 is mounted in the mounting hole 113 , along 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 surface 122 of the pole to the mounting hole 113 .

[0183] 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 racetrack-shaped cross-section (a structure formed by two arcs and two straight lines), 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.

[0184] 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.

[0185] It should also 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.

[0186] In addition, it is worth noting that the first volume V1 of the first receiving tank 12110 is the difference between the total volume V2 of the first receiving tank 12110 and the volume of the first receiving tank 12110 required to accommodate other components except the conductive portion 22 (recorded as the second volume V3), that is, V1 = V2 - V3. It is understandable that when the first receiving tank 12110 does not need to accommodate other components except the conductive portion 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.

[0187] Please refer again to Figures 8 and 9. To ensure the stability and reliability of the electrical connection between the active material coating portion 21 and the first electrode 12, in an embodiment of the present application, the electrical connection location between the conductive portion 22 and the first electrode 12 can be located on the 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 location is the welding location 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 location is the electrical connection location of the conductive portion 22 and the first electrode 12.

[0188] 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 position 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 can be welded to at least one of the first end wall 12111 and the first side wall 12113.

[0189] In the above technical solution, by arranging the electrical connection position 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 serves to accommodate at least a portion of the conductive portion 22, but the groove wall of the first receiving groove 12110 also serves to establish an electrical connection with the conductive portion 22. This simplifies the structure of the first terminal 12, facilitates the processing of the first terminal 12, simplifies the structure of the conductive portion 22, reduces redundancy in the conductive portion 22, and reduces the cost of the conductive portion 22. Furthermore, by utilizing the groove wall of the first receiving groove 12110 to establish an electrical connection with the conductive portion 22, the area where the conductive portion 22 is electrically connected to the first terminal 12 can be set relatively large, which not only reduces the difficulty of electrical connection, but also improves the reliability and stability of the electrical connection, thereby improving the performance of the battery cell 10.

[0190] 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.

[0191] 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.

[0192] Referring again to Figures 8 and 9 , in the embodiment of the present application, the partial shape of the conductive portion 22 matches the partial shape of the first end wall 12111, and they are arranged to fit and electrically connect, such that the location 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 fit to the first end wall 12111, and an electrical connection, such as welding, can be made at the fitting location. This can increase the area of ​​the electrical connection, improving the reliability and stability of the electrical connection.

[0193] 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.

[0194] 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.

[0195] 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.

[0196] FIG10 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application. Referring to FIG10 , in the 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 sinking in a direction 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 provided within the first sinking groove 12112 and connected to the portion of the first end wall 12111 that defines the first sinking groove 12112.

[0197] 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.

[0198] 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.

[0199] Of course, 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 set 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.

[0200] 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 racetrack-shaped, the first end wall 12111 is rectangular or racetrack-shaped, and there are four first side walls 12113, each connected to the four sides of the first end wall 12111.

[0201] 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.

[0202] 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 terminal 12 may not be located within the first receiving groove 12110. For example, the electrical connection position between the conductive portion 22 and the first terminal 12 may also be located on the terminal inner end surface 122. In this case, part of the conductive portion 22 is accommodated within the first receiving groove 12110, which can also save space to a certain extent and improve the energy density of the battery cell 10.

[0203] Please refer to Figures 9 and 10 again. In the 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.

[0204] It is understood that the first groove 126 is a groove body, which is a groove-like structure with a certain depth. Moreover, when the first pole 12 is arranged 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 the groove opening open upward and the groove wall concave downward (i.e., concave toward the square near the battery cell assembly 2). For another example, when the first pole 12 is arranged 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 the groove opening open downward and the groove wall concave upward (i.e., concave toward the square near the battery cell assembly 2).

[0205] 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.

[0206] 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.

[0207] 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 conductive part 22 to the groove wall of 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 10 can be laser welded to the conductive part 22 to achieve electrical connection between the battery cell assembly 2 and the first pole 12. 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.

[0208] In some embodiments, the first receiving groove 12110 can be configured in a cross-sectional shape with a length greater than width, such as a rectangle, an ellipse, a racetrack, 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.

[0209] Referring to FIG. 9 again, the housing assembly 1 may further include a slot cover 7 . The slot cover 7 is disposed on the first pole 12 and covers the notch of the first groove 126 .

[0210] 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.

[0211] It should be noted that, based on the solution that the accommodating portion 121 includes the first accommodating groove 12110 , the specific structure of the battery cell assembly 2 of the embodiment of the present application is not limited, and for example, may include but is not limited to the following two implementations.

[0212] Figure 11 is a partial cross-sectional schematic diagram of the battery cell assembly 2 provided in some embodiments of the present application. Please refer to Figures 9 to 11. In the first embodiment, 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 pole ear sheets 2211 are structures that are electrically connected to the current collector 211 but are not coated with active materials. They can be formed by directly die-cutting the current collector 211. The plurality of pole ear sheets 2211 converge near the current collector 211 (that is, gather in a direction close to each other) to form a first gathered portion 2212. The plurality of pole ear sheets 2211 converge away from the current collector 211 and are connected to form a second gathered portion 2213. The first gathered portion 2212 connects the second gathered portion 2213 and the active material coating portion 21. When the accommodating portion 121 has a first accommodating groove 12110 , at least a portion of the second retracted portion 2213 may be accommodated in the first accommodating groove 12110 .

[0213] 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 can be connected into an integrated plate structure by welding (e.g., ultrasonic welding) to form the second gathered portion 2213. For example, the plurality of tabs 2211 can 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.

[0214] 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.

[0215] 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.

[0216] 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.

[0217] 10-11 , 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 column 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.

[0218] In this embodiment, the second gathered portion 2213 is directly or indirectly electrically connected to the first terminal 12. For example, referring to FIG9 , 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.

[0219] 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, referring to FIG10 , 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.

[0220] 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).

[0221] 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.

[0222] 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, thereby making the welding between the adapter plate 222 and the first pole 12 more secure, reducing the risk of welding cracking, and further improving the reliability and stability of the battery cell 10; at the same time, electrically connecting the first pole 12 and the pole tab 2211 through the adapter plate 222 can also simplify the structure of the pole tab 2211.

[0223] 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.

[0224] Referring to Figures 10 and 11 , 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.

[0225] 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.

[0226] 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.

[0227] 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.

[0228] 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.

[0229] FIG12 is a diagram of various tab folding schemes for the battery cell assembly 2 provided in some embodiments of the present application. Please refer to FIG11 and FIG12. 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 position between the two electrode assemblies 2a to form a symmetrical folding form (for example, as shown in FIG11 and FIG12(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 toward one of the electrode assemblies 2a to form an asymmetrical folding form (for example, as shown in FIG12(b) and FIG12(c)). In addition, the electrode assembly 2a can be in a full-tab form (for example, as shown in FIG12(a)) or a half-tab form (for example, as shown in FIG11, FIG12(b) and FIG12(c)).

[0230] Of course, 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.

[0231] 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.

[0232] For example, Figure 13 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Please refer to Figure 13. In the 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.

[0233] 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.

[0234] In the above technical solution, referring to FIG. 13 , 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, thereby improving 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 on the side away from the active material coating portion 21, the second receiving groove 12120 can be open in a direction away from the active material coating portion 21. In this way, when at least a portion of the conductive portion 22 is received in the second receiving groove 12120, the conductive portion 22 can be easily stored and arranged 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 difficulty of producing the battery cell 10 and improving the production efficiency of the battery cell 10.

[0235] 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.

[0236] 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.

[0237] 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 an embodiment 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 .

[0238] In the above technical solution, the electrical connection position between the conductive part 22 and the first pole 12 is set on the 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 sealing of the first through-hole 12130, thereby saving sealing costs, reducing electrolyte leakage, and saving sealing parts.

[0239] 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.

[0240] 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.

[0241] Specifically, Figure 14 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Please refer to Figures 13 and 14. 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. 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.

[0242] 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.

[0243] 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.

[0244] 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.

[0245] 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.

[0246] Referring again to Figures 13 and 14, 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 to fit and electrically connect to the second end wall 12121, such that the portion where the conductive portion 22 electrically connects to the second end wall 12121 extends along the length or width of the second end wall 12121. For example, if the second end wall 12121 is planar, a portion of the conductive portion 22 can also be planar and fit to the second end wall 12121, and an electrical connection, such as welding, can be made at the fitting portion. This can increase the area of ​​the electrical connection, improving the reliability and stability of the electrical connection.

[0247] 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.

[0248] For example, referring to Figures 13 and 14 , 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.

[0249] For another example, FIG15 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application. Referring to FIG15 , the angle θ between the second end wall 12121 and the axial direction R of the first terminal 12 is greater than 90°. That is, along the direction from the first through-hole 12130 to the second sidewall 12123, the second end wall 12121 extends obliquely toward the active material coating portion 21. As a result, the conductive portion 22 extends a greater distance along the second end wall 12121, thereby enhancing the reliability of the electrical connection. For example, the angle θ between the second end wall 12121 and the axial direction R of the first terminal 12 can be 90°-145°, such as 100°, 110°, 120°, 130°, 140°, and so on. This makes the second end wall 12121 easier to process and facilitates electrical connection to the conductive portion 22, while also making more efficient use of the space within the first terminal 12 to accommodate the conductive portion 22.

[0250] For another example, FIG16 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application. Referring to FIG16 , the angle θ between the second end wall 12121 and the axial direction R of the first terminal 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 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, thereby improving the reliability of the electrical connection. Exemplarily, the angle θ between the second end wall 12121 and the axial direction R of the first terminal 12 can be 45°-90°, such as 50°, 60°, 70°, 80°, etc. This makes the second end wall 12121 easier to process and facilitates electrical connection to the conductive portion 22. Furthermore, the space within the first terminal 12 can be more fully utilized to accommodate the conductive portion 22.

[0251] Of course, 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, and 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.

[0252] Referring again to FIG. 14 , 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.

[0253] 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.

[0254] 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.

[0255] 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.

[0256] 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, which is annular and 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 racetrack-shaped, the second end wall 12121 is rectangular or racetrack-shaped, and there are four second side walls 12123, each connected to the four sides of the second end wall 12121.

[0257] It should also be noted that the second receiving groove 12120 is not limited to the form defined by the second end wall 12121 and the second side wall 12123. For example, in some embodiments, Figure 17 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Please refer to Figure 17. One end of the notch of each second side wall 12123 away from the second receiving groove 12120 extends to the first perforation 12130, so that the second receiving 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.

[0258] In some embodiments, referring to FIG. 29 , the accommodating portion 121 may 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 third accommodating groove 12140 is a groove body, which is a groove-shaped structure with a certain depth. 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. The notch of the second accommodating groove 12120 is formed on the inner end face 122 of the first pole 12. 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.

[0259] 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 again to FIG. 17 , 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.

[0260] Referring again to FIG. 13 , 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 so that the first pole 12 can be mounted to the housing 11 through the mounting hole 113.

[0261] Optionally, referring to Figure 13, 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.

[0262] In some embodiments, please refer to Figure 13. 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.

[0263] 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 racetrack-shaped 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 racetrack shape described herein refers to a shape in which the two short sides of a rectangle are replaced by convex curves, for example, see the shape shown in Figure 19(b).

[0264] 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 pole 12. Since the depth H3 of the second receiving groove 12120 is greater than or equal to the minimum distance H4 between the pole outer end surface 123 and the mounting hole 113 in the axial direction R of the first pole 12, the volume of the first pole 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, thereby greatly reducing the space occupied by the conductive portions 22 within the housing 11, 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, due to the greater depth of the second receiving groove 12120, it 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.

[0265] 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 , 600mm3 , 700mm 3 , 800mm 3 , 1000mm 3 etc.

[0266] 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.

[0267] 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.

[0268] For example, FIG18 is an enlarged partial view of point B in FIG3 ; FIG19 is an orthographic view of various first electrodes 12 provided in some embodiments of the present application. Referring to FIG18 and FIG19 , regarding the shape of the first through-hole 12130, in embodiments of the present application, the first through-hole 12130 can be 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 an elongated strip, the second receiving groove 12120 can also be configured with a cross-sectional shape that is longer than its width, such as a rectangular, elliptical, or racetrack shape. In this case, the length of the first through-hole 12130 can be aligned with the length of the cross-sectional shape of the second receiving groove 12120, thereby fully utilizing space. Furthermore, the weld mark formed by welding the conductive portion 22 to the first electrode 12 can be an elongated strip parallel to the length 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.

[0269] 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 part 22. For example, when there is only one first through-hole 12130 opened on the second receiving groove 12120, in some examples, please refer to Figures 18 and 19, the first through-hole 12130 can be centered relative to the second receiving groove 12120. In other examples, Figure 20 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Please refer to Figure 20, the first through-hole 12130 can also be offset relative to the center of the second receiving groove 12120. For example, in some embodiments, referring to Figure 20, 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, thereby increasing the available area of ​​the second end wall 12121 to increase the welding area between the conductive part 22 and the second end wall 12121.

[0270] It is understood that after the conductive portion 22 passes through the first through-hole 12130, it will be folded 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 18), thereby appropriately reducing the size of the second receiving groove 12120 and enhancing the structural compactness and strength. Alternatively, Figure 21 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Referring to Figure 21, after the conductive portion 22 passes through the first through-hole 12130, it can also be folded toward opposite sides simultaneously to reduce the thickness of the weld, reduce the welding heat input, and thus reduce problems such as particle splashing.

[0271] For example, when there are multiple first through-holes 12130 opened 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 position relationship of the multiple first through-holes 12130. For example, Figure 22 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Please refer to Figure 22. When there are two first through-holes 12130 opened on the second receiving groove 12120 and they are far away from each other, the two conductive portions 22 passing through the two first through-holes 12130 can be folded in a direction close to each other; and when there are two first through-holes 12130 opened 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.

[0272] 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.

[0273] In addition, in some embodiments, please refer to Figures 20 and 21, the first through-hole 12130 can be centered relative to the active material coating portion 21, but the position of the first through-hole 12130 relative to the second receiving groove 12120 is not limited, and can be centered or offset. Since the first through-hole 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.

[0274] In some embodiments, referring to FIG. 21 , a sealing member 6 may be provided at the first through-hole 12130 to improve the problem of electrolyte in the housing 11 leaking from the first through-hole 12130. The material, shape, and connection method of the sealing member 6 with the first through-hole 12130 are not limited. For example, the sealing member 6 may be a metal member made of the same material as the first pole 12 or the conductive portion 22, which may be welded to the wall surface of the first through-hole 12130 of the first pole 12 to seal the first through-hole 12130. For another example, the sealing member 6 may be rubber or plastic, etc., which is plugged into and interference-fitted with the first through-hole 12130 to seal the first through-hole 12130. In the embodiments of the present application, all of these can be designed according to actual requirements without limitation.

[0275] Figure 23 is a structural explosion diagram of the battery cell 10 provided in some embodiments of the present application; Figure 24 is a partial cross-sectional schematic diagram of the shell assembly 1 provided in some embodiments of the present application, and Figure 25 is a structural explosion diagram of the shell assembly 1 shown in Figure 24. Please refer to Figures 23, 24 and 25. In the embodiments of the present application, when the accommodating portion 121 has the second accommodating groove 12120 of any of the above-mentioned 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.

[0276] 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.

[0277] It is worth noting that the manner and position of cooperation between 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 slot 12120. For example, in some embodiments, referring to FIG. 22 , 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 slot 12120. The first cover plate 13 and the first terminal 12 are then welded to close the notch of the second receiving slot 12120.

[0278] It should also be noted that the specific structure of the first cover plate 13 is not limited. For example, in some optional embodiments, FIG26 is an exploded view of the structure of the first cover plate 13 shown in FIG25 . Referring to FIG24-26 , 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.

[0279] 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.

[0280] 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.

[0281] Referring again to Figures 24-26, 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 corrosion of the second conductive member 132 by the electrolyte.

[0282] 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 24-26, 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.

[0283] 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.

[0284] 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.

[0285] 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.

[0286] 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, Figure 27 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application, and Figure 28 is a structural explosion diagram of the battery cell 10 shown in Figure 27. Please refer to Figures 27 and 28. The first cover plate 13 can also be set as a non-composite form made of the same material, for example, to adapt to the positive electrode column, which will not be elaborated here.

[0287] Referring again to Figures 24-26, 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.

[0288] 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.

[0289] Referring again to Figures 24-26, 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 formed into a guiding bevel 12126. The guiding bevel 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 bevel, 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 guiding bevel 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.

[0290] Specifically, referring to Figures 24-26, 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.

[0291] 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.

[0292] 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.

[0293] Referring again to Figures 24-26, 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.

[0294] 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.

[0295] 27-28 , in an embodiment of the present application, the housing assembly 1 may further be provided with a second cover plate 14 as required. The second cover plate 14 is disposed outside the first through-hole 12130 and is simultaneously located outside the conductive portion 22 in the second receiving groove 12120 .

[0296] 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.

[0297] 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.

[0298] For example, as shown in Figures 27 and 28, 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.

[0299] 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 27 and 28 , 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.

[0300] 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.

[0301] 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.

[0302] 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.

[0303] For example, please refer to Figures 27-28. 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 confluence 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 confluence component are made of the same material and can be effectively welded.

[0304] 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.

[0305] FIG29 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application. Referring to FIG29 , in a 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 accommodating portion 121 has a second accommodating groove 12120, at least a portion of the second gathered portion 2213 is accommodated within the second accommodating groove 12120.

[0306] 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.

[0307] In some optional examples, please refer to Figure 29, 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.

[0308] 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.

[0309] Please refer to Figure 29. 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 a portion of the first retracted portion 2212 can be accommodated in the third accommodating groove 12140.

[0310] 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.

[0311] 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 racetrack-shaped 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 the embodiment of the present application, the third receiving groove 12140 can be configured in a shape with a cross-sectional length greater than its width, such as a rectangular, elliptical, or racetrack-shaped shape, to facilitate the storage of the first gathering portion 2212.

[0312] 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.

[0313] As an optional solution, the conductive portion 22 can also be provided with an adapter plate 222 as required, in which case the second retracted portion 2213 is indirectly electrically connected to the first pole 12. Specifically, FIG30 is a partial cross-sectional schematic diagram of a battery cell 10 provided in some embodiments of the present application. Referring to FIG30 , when the conductive portion 22 includes the adapter plate 222, the adapter plate 222 is connected to the second retracted portion 2213, and the conductive portion 22 is electrically connected to the first pole 12 via the adapter plate 222. At this time, at least a portion of the adapter plate 222 is accommodated in the second receiving groove 12120. In this example, at least a portion of the second retracted portion 2213 is also accommodated in the second receiving groove 12120.

[0314] 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).

[0315] 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.

[0316] 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.

[0317] 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.

[0318] Referring to FIG. 30 , in a 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.

[0319] 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.

[0320] 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.

[0321] 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.

[0322] Figure 31 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Please refer to Figure 31. In some other embodiments of the present application, the accommodating portion 121 has a fourth accommodating groove 12150, and the fourth accommodating groove 12150 is a groove body, which is a groove-shaped structure with a certain depth. The surface 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 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 part 22 may not be accommodated in the fourth accommodating groove 12150. For example, the conductive part 22 may be passed through the second through-hole 12160, and the electrical connection position between the conductive part 22 and the first pole 12 is located at the hole wall of the second through-hole 12160 formed by the first pole 12.

[0323] 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.

[0324] 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 runway-shaped 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.

[0325] 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 slot 12150 can also be configured in a shape where the cross-section is longer than the width, such as a rectangular, elliptical, or racetrack shape. In this case, the length direction of the second through-hole 12160 can be aligned with the length direction of the cross-section of the fourth receiving slot 12150, thereby fully utilizing the space.

[0326] 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, FIG32 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application. Referring to FIG32 , the accommodating portion 121 may only have the 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 through the third through-hole 12170. 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 wall of the third through-hole 12170 formed in the first pole 12, 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 surface 123 outside the third through-hole 12170. In addition, the shape of the third through-hole 12170 is not limited. It can be a regular-shaped hole with a uniform cross-section, or a variable-shaped hole with unequal cross-sections, etc. Furthermore, the cross-sectional shape of the third through-hole 12170 is not limited. For example, it can be an elongated strip, such as a rectangle, an ellipse, or a racetrack, etc., to match the sheet-shaped partial shape of the conductive portion 22, thereby facilitating the sheet-shaped partial portion of the conductive portion 22 to pass through the third through-hole 12170. This will not be described in detail here.

[0327] Figure 33 is a partial cross-sectional schematic diagram of the battery cell 10 provided in some embodiments of the present application, Figure 34 is a schematic diagram of the cooperation between the battery cell assembly 2 and the bracket 3 provided in some embodiments of the present application, and Figure 35 is a cross-sectional view along the CC line in Figure 34; please refer to Figures 33-35. In the 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.

[0328] 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.

[0329] Please refer to Figures 33 to 35 again. Optionally, the bracket 3 is provided with a guide portion 32, which surrounds at least a portion of the avoidance hole 31, and at least a portion of the guide portion 32 extends to the accommodating portion 121.

[0330] 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.

[0331] Please refer to FIG. 33 to FIG. 35 again. 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 .

[0332] 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.

[0333] Furthermore, in some embodiments, the guide portion 32 can be used to help define the third groove 38, thereby simplifying the structure of the bracket 3, reducing the difficulty of designing and processing the bracket 3, and facilitating increasing the wall thickness of the guide portion 32, thereby improving the guiding reliability of the conductive portion 32. Furthermore, this also helps improve the stability and reliability of the first pole 12, thereby ensuring the reliability and stability of the electrical connection between the first pole 12 and the battery cell assembly 2, and thus improving the reliability and stability of the charging and discharging operations of the battery cell 10.

[0334] Please refer to Figures 33-35 again. Optionally, in an embodiment of the present application, 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.

[0335] 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.

[0336] In the embodiments of the present application, the bracket 3 may be an integral structure or a split structure. Figure 36 is a schematic structural diagram of the integral bracket 3 provided in some embodiments of the present application. Please refer to Figure 36. When the bracket 3 is an integral structure, the avoidance hole 31 is formed in the form of a through hole that passes through 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 better, and it is 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.

[0337] FIG37 is a schematic diagram of the structure of a split bracket 3 provided in some embodiments of the present application. Referring to FIG37 , when the bracket 3 is a split structure, the bracket 3 includes a detachable first bracket 33 and a second bracket 34. The first bracket 33 and the second bracket 34 are both long, plate-like structures. The two can be detachably connected, for example, the two can be plugged or snap-fitted to facilitate assembly. At the same time, the first bracket 33 has a semi-hole structure on the side close to the second bracket 34, and the second bracket 34 is also provided with another semi-hole structure of the same shape close to the first bracket 33. The semi-hole structure of the first bracket 33 and the semi-hole structure of the second bracket 34 together form an annular avoidance hole 31. That is, the avoidance hole 31 is defined between the first bracket 33 and the second bracket 34.

[0338] 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.

[0339] 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.

[0340] Figure 38 is a partial cross-sectional schematic diagram of the battery cell assembly 2 and the bracket 3 provided in some embodiments of the present application, and Figure 39 is a structural exploded view of the battery cell assembly 2, the bracket 3 and the shell assembly 1 provided in some embodiments of the present application. Please refer to Figures 33, 38 and 39. In the embodiments of the present application, the structure of the bracket 3 is not limited to this. For example, the edge of the bracket 3 can also be provided with a shell entry guide surface 35. The shell entry guide surface 35 can be an inclined surface or a curved surface, and is projected along the axial direction R of the first pole 12. The orthographic projections of the active material coating portion 21 are all located 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. 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.

[0341] Please refer to Figure 38. In the embodiment 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, and 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 the 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.

[0342] Referring to Figure 38 , in the embodiment of the present application, the bracket 3 includes a main body 36 and an extension 37. The main body 36 is located on the side of the active material coating portion 21 near the first pole 12. The extension 37 is connected to the main body 36 and is located in the peripheral area of ​​the active material coating portion 21. For example, the extension 37 can be connected to the circumferential edge of the main body 36 to form an annular extension structure connected to the main body 36, or it can be a partial extension of the circumference of the main body 36 to form a block-like structure protruding relative to the main body 36. On the one hand, the provision of the extension 37 can limit the active material coating portion 21 to improve the problem of carbon powder falling off the edge of the active material coating portion 21 and overlapping with the shell 11, which causes corrosion. On the other hand, the provision of the extension 37 can also fix the internal insulator 4, improve the connection reliability between the internal insulator 4 and the bracket 3, and provide a better insulation effect.

[0343] For example, referring to Figure 38, 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. 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.

[0344] Specifically, referring to Figure 39, 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. 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.

[0345] In the embodiment of the present application, the specific manner of setting the first pole 12 on the housing 11 is not limited, and may be, for example, riveting or welding, etc., which are described below respectively.

[0346] For example, in some embodiments, Figure 40 is a structural exploded view of the first pole 12, the shell 11, and the sealing gasket provided in some embodiments of the present application; Figure 41 is an assembly view of the first pole 12 shown in Figure 40, the shell 11, and the sealing gasket; Figure 42 is a structural schematic diagram of the first pole 12 provided in some embodiments of the present application. Please refer to Figures 40-42. 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 improving compactness.

[0347] Specifically, please refer to Figures 40 to 42. Before the first pole 12 is riveted, it can include a stopper 1281 and a penetration portion 1282. During assembly, the stopper 1281 is stopped inside the shell 11, and the penetration portion 1282 is penetrated into the mounting hole 113. Then, the portion of the penetration portion 1282 located outside the shell 11 is riveted to form a flange portion 1283. The flange portion 1283 is stopped outside the shell 11, thereby realizing the installation of the first pole 12.

[0348] Optionally, referring to Figures 40 and 41 , the housing assembly 1 may include a plurality of sealing gaskets, such as the first sealing gasket 191 and the second sealing gasket 192 shown in Figure 40 , 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 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.

[0349] Optionally, referring to FIG41 , 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 strong vibration.

[0350] For another example, in other embodiments of the present application, FIG43 is an assembly diagram of the first pole 12, the housing 11, and the sealing gasket provided in some embodiments of the present application; FIG44 is an exploded view of the structure of the first pole 12 shown in FIG43. Referring to FIG43 and FIG44, the first pole 12 can 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, wherein at least a portion of the first portion 1291 is retained outside the housing 11, and at least a portion of the second portion 1292 is retained inside the housing 11. The first pole 12 can 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.

[0351] In some optional embodiments, Figure 45 is an orthographic projection view of the battery cell 10 provided in some embodiments of the present application; Figure 46 is an orthographic projection view of the battery cell 10 provided in some embodiments of the present application. Please refer to Figures 45 and 46. There are multiple first poles 12 and they are all located on the same side surface of the shell 11, thereby facilitating installation and improving assembly efficiency.

[0352] 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, racetrack, 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.

[0353] For example, in the example shown in FIG45 , 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. Alternatively, referring to FIG45 , 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 collecting 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.

[0354] In addition, referring to FIG. 45 , when the first wall 110 has two first poles 12 and the two first poles 12 are spaced apart along the length direction 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 3 / 4 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 30 mm.

[0355] For example, in the example shown in FIG46 , 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. Alternatively, referring to FIG46 , 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.

[0356] In addition, referring to FIG. 46 , when the first wall 110 has four first poles 12, with two first poles 12 spaced apart along the width direction of the first wall 110 to form a group, with a total of two groups spaced apart along the length direction 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.

[0357] In some embodiments, referring to FIG45 and FIG46 , 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 bus component, increases the effective flow area between the first pole 12 and the current bus component, and helps increase the charging speed of the battery cell 10.

[0358] In addition, in some embodiments, Figure 47 is a cross-sectional view along line DD in Figure 46. Referring to Figure 47, 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.

[0359] Figure 48 is a schematic cross-sectional view of a housing assembly 1 according to some embodiments of the present application; Figure 49 is a schematic cross-sectional view of a housing assembly 1 according to some embodiments of the present application; Figure 50 is an orthographic view of a battery cell 10 according to some embodiments of the present application; Figure 51 is a cross-sectional view taken along line EE in Figure 50; and Figure 52 is a schematic partial cross-sectional view of a battery cell 10 according to some embodiments of the present application. Referring to Figures 48 to 52, in the embodiments of the present application, the housing 11 specifically includes a housing body 111 and a housing cover 112. The housing body 111 is a square ring-shaped structure with one or both ends open. When one end is open, there is one housing cover 112, which is positioned in the open position. When both ends are open, there are two housing covers 112, one covering each of the open ends of the housing body 111.

[0360] 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, referring to FIG. 48 , the first pole 12 can be provided at one 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 prone to cracking, 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.

[0361] As an optional solution, referring again to FIG. 48 , 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. Consequently, 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, making the connection between the housing 111 and the housing cover 112 less susceptible to cracking, 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 reduces cost and weight, and facilitates miniaturization of the battery cell 10.

[0362] When the above-mentioned first receiving groove 12110 corresponding to the mounting hole 113 is opened on the first pole 12, the wall thickness of the part of the first pole 12 located on the side of the first receiving groove 12110 away from the active material coating part 21 is thinner, so that the welding of the conductive part 22 and the first pole 12 can be achieved from the outside of the shell 11. Please refer to Figure 48. 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 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.

[0363] When the above-mentioned second accommodating groove 12120 is opened on the first pole 12, since the conductive part 22 and the first pole 12 can be welded from the outside of the shell 11 through the notch of the second accommodating groove 12120, please refer to Figure 48. 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 that it is difficult to weld 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.

[0364] Of course, referring to Figure 49, 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.

[0365] 50 to 52 , in the embodiment of the present application, when there are multiple first poles 12, the first poles 12 may be disposed on two surfaces on different sides of the housing 11. For example, there may be multiple first poles 12 disposed on two adjacent surfaces of the housing 11, or there may be multiple first poles 12 disposed on two opposite surfaces of the housing 11.

[0366] When first poles 12 are provided on opposite sides of the housing 11, conductive portions 22 can extend from the active material coating portion 21 near the first pole 12 on each side. The conductive portions 22 cooperate with and connect to the first pole 12 on the adjacent side, thereby improving the problem of the pole ear 221 being pulled by the first pole 12 on the same side, which could cause cracking in 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, without limitation herein.

[0367] Of course, in other embodiments of the present application, the first pole 12 can also be arranged on the side surface with the largest area of ​​the shell 11. For another example, in some optional embodiments of the present application, the first pole 12 can be located on the top surface of the shell 11. For another example, in some optional embodiments of the present application, the first pole 12 can be located on the bottom surface of the shell 11, and so on. Among them, when the first pole 12 is located on the bottom surface of the shell 11, the accommodating portion 121 can be used to accommodate the electrolyte, thereby improving the cycle life of the battery cell 10. In addition, when the first pole 12 is located on the bottom surface of the shell 11 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, thereby reducing the stress concentration problem and eliminating other supporting structural parts.

[0368] FIG53 is a schematic diagram of the structure of the housing cover 112 provided in some embodiments of the present application. Referring to FIG53 , in the embodiments of the present application, the housing 11 is provided with a pressure relief portion 16. The specific configuration of the pressure relief portion 16 is not limited, and 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.

[0369] Optionally, the pressure relief portion 16 and the first pole 12 can be located on the same side of the housing 11. This facilitates processing and assembly. Alternatively, the pressure relief portion 16 and the first pole 12 can be located on opposite sides of the housing 11. This saves space, increases the volume of the first pole 12, and reduces the adverse effects of the pressure relief portion 16 on the first pole 12 when releasing pressure.

[0370] Please refer to Figures 48 and 53 again. In the embodiment of the present application, the pressure relief portion 16 can also be provided on the shell cover 112 as needed. Since the shell cover 112 does not need to bear the function of installing the first pole 12, and the connection position between the shell cover 112 and the shell body 11 is less affected by vibration during the charging and discharging process of the battery cell 10 and is not easy to crack, the thickness of the shell cover 112 is set to be relatively thin, which makes it easier to process and manufacture the pressure relief portion 16. For example, it is convenient to directly form the pressure relief portion 16 on the shell cover 112 by an integrated notch, so as to fully improve the manufacturability of the battery cell 10. It is worth noting that in this embodiment, the first pole 12 can be provided on the shell body 111 or the shell cover 112, and there is no limitation here. For example, the pressure relief portion 16 can be integrally formed with the shell cover 112, thereby facilitating processing, simplifying assembly, improving production efficiency, and reducing costs.

[0371] Please refer to FIG. 3-FIG . 5 , FIG. 18 , and FIG. 23 - FIG. 24 again for a description of the battery cell 10 according to a specific embodiment of the present application.

[0372] In the embodiment of the present application, the battery cell 10 is a rectangular parallelepiped, with the height direction of the battery cell 10 being a first direction Z, the length direction of the battery cell 10 being a second direction X, and the thickness direction of the battery cell 10 being a third direction Y. The battery cell 10 includes a housing 11, which includes 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.

[0373] At the same time, two poles are provided at the closed end of the shell body 111 along the first direction Z. The two poles are spaced apart along the second direction X and are respectively a positive pole and a negative pole. Both poles are first poles 12 provided with an accommodating portion 121, and the accommodating portion 121 includes a second accommodating groove 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 close to the shell cover 112. The second end wall 12121 and the second side wall 12123 are arranged to form the second accommodating groove 12120. The surface of the first pole 12 away from the shell cover 112 is the pole outer end surface 123. The notch of the second accommodating groove 12120 is formed on the pole outer end surface 123. A first through-hole 12130 is opened on the second end wall 12121. The first through-hole 12130 is located at a position of the second end wall 12121 close to the second side wall 12123.

[0374] In addition, the battery cell 10 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 into the second accommodating groove 12120 through the first through-hole 12130 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.

[0375] In addition, 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.

[0376] 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.

[0377] 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.

[0378] 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.

[0379] 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.

[0380] In the above technical solution, since the battery 100 is provided with the above-mentioned battery cell 10, and since the first electrode 12 of the battery cell 10 is provided with the accommodating portion 121, the weight of the first electrode 12 can be reduced to a certain extent, thereby improving the weight energy density of the battery cell 10 and the battery 100; on the other hand, by accommodating at least a portion of the conductive portion 22 in the accommodating portion 121 to occupy the space in the first electrode 12, it is beneficial to improve the volume energy density of the battery cell 10, or reduce the space occupied by the battery cell 10 itself, so that the battery 100 of the same volume can accommodate a larger number of battery cells, thereby helping to improve the volume energy density of the battery 100; in addition, accommodating at least a portion of the conductive portion 22 in the accommodating portion 121 can also reduce the redundancy of the conductive portion 22 in the shell 11 to a certain extent, reduce the probability of short circuit between the conductive portion 22 and the active material coating portion 21, thereby improving the working reliability and stability of the battery cell 10 and the battery 100. According to some embodiments of the present application, the present application further provides an electric device 1000 , which includes the battery 100 of the above embodiment, and the battery 100 is used to provide electric energy for the electric device 1000 .

[0381] In the above technical solution, since the power consumption device 1000 is provided with the above-mentioned battery 100, the energy density of the battery 100 can be increased, thereby facilitating an increase in the service life of the power consumption device 1000. Furthermore, since the operating reliability and stability of the battery 100 can be improved, the operating reliability and stability of the power consumption device 1000 can be improved. It is understood that when the power consumption device 1000 is a vehicle, the increased service life of the battery 100 can help to increase the vehicle's range.

[0382] 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.

[0383] 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 (10), wherein: include: A housing assembly (1) comprises a housing (11) and a first pole (12) arranged on the housing (11), wherein the first pole (12) is provided with a receiving portion (121); A battery cell assembly (2), comprising an active material coating portion (21) and a conductive portion (22), wherein the active material coating portion (21) is accommodated in the housing (11), and the conductive portion (22) is used to electrically connect the active material coating portion (21) and the first pole (12); Wherein, at least a portion of the conductive portion (22) is accommodated in the accommodation portion (121).

2. The battery cell (10) according to claim 1, 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).

3. The battery cell (10) according to claim 2, 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).

4. The battery cell (10) according to claim 2 or 3, wherein: The first pole (12) 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 receiving 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).

5. The battery cell (10) according to claim 4, 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).

6. The battery cell (10) according to any one of claims 2 to 5, 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).

7. The battery cell (10) according to claim 6, wherein: The housing assembly (1) further comprises a slot cover (7), wherein the slot cover (7) is arranged on the pole (12) and covers the slot opening of the first groove (126).

8. The battery cell (10) according to any one of claims 2 to 7, wherein: The active material coating portion (21) comprises a current collector (211) and an active material layer (212) disposed on the current collector (211); the conductive portion (22) comprises a pole ear portion (221) electrically connected to the current collector (211); the pole ear portion (221) comprises a plurality of pole ear sheets (2211); the plurality of pole ear sheets (2211) converge at a position close to the current collector (211) to form a first gathered portion (2212); the plurality of pole ear sheets (2211) converge at a position away from the current collector (211) and are connected to form a second gathered portion (2213); the first gathered portion (2212) connects the second gathered portion (2213) and the active material coating portion (21); and at least a portion of the second gathered portion (2213) is accommodated in the first accommodation groove (12110).

9. The battery cell (10) according to claim 8, wherein: At least a portion of the first retracted portion (2212) is accommodated in the first accommodating groove (12110).

10. The battery cell (10) according to claim 8 or 9, wherein: The conductive part (22) further comprises a transfer plate (222), wherein the transfer plate (222) is connected to the second retracted part (2213), and the conductive part (22) is electrically connected to the first pole (12) via the transfer plate (222), and at least a portion of the transfer plate (222) is accommodated in the first accommodation groove (12110).

11. The battery cell (10) according to any one of claims 2 to 7, wherein: The active material coating portion (21) comprises a current collector (211) and an active material layer (212) disposed on the current collector (211); the conductive portion (22) comprises a pole ear portion (221) and a transfer sheet (222); the pole ear portion (221) comprises a plurality of pole ear sheets (2211) electrically connected to the current collector (211); a plurality of pole ear sheets (2211) converge at positions close to the current collector (211) to form a first gathered portion (2212); a plurality of pole ear sheets (2211) converge at positions away from the current collector (211) and are connected to form a second gathered portion (2213); the transfer sheet (222) is electrically connected to the second gathered portion (2213); at least a portion of the transfer sheet (222) is accommodated in the first accommodation groove (12110) and is electrically connected to the first pole (12).

12. The battery cell (10) according to claim 1, 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).

13. The battery cell (10) according to claim 12, 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 first pole (12).

14. The battery cell (10) according to claim 12, wherein: The first pole (12) comprises a second end wall (12121) and a second side wall (12123), the second end wall (12121) being 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) being arranged to form the second receiving groove (12120), the first through hole (12130) being opened on the second end wall (12121), and the electrical connection position between the conductive portion (22) and the first pole (12) being located on the second end wall (12121) and / or on the second side wall (12123).

15. The battery cell (10) according to claim 14, 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).

16. The battery cell (10) according to any one of claims 12 to 15, 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).

17. The battery cell (10) according to any one of claims 12 to 16, 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).

18. The battery cell (10) according to claim 17, 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).

19. The battery cell (10) according to claim 18, 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).

20. The battery cell (10) according to any one of claims 17 to 19, wherein: The first cover plate (13) is embedded in the notch of the second receiving groove (12120).

21. The battery cell (10) according to claim 20, 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).

22. The battery cell (10) according to claim 20 or 21, 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).

23. The battery cell (10) according to any one of claims 17 to 22, wherein: The first cover plate (13) is provided with a stress release groove (133), and the stress release groove (133) is located in the outer peripheral area of ​​the first cover plate (13).

24. The battery cell (10) according to any one of claims 12 to 23, wherein: The housing assembly (1) further comprises a second cover plate (14), wherein the second cover plate (14) covers the first through hole (12130) and the conductive portion (22) located in the second receiving groove (12120).

25. The battery cell (10) according to any one of claims 1 to 24, 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).

26. The battery cell (10) according to any one of claims 12 to 24, wherein: The active material coating portion (21) comprises a current collector (211) and an active material layer (212) disposed on the current collector (211); the conductive portion (22) comprises a pole ear portion (221) electrically connected to the current collector (211); the pole ear portion (221) comprises a plurality of pole ear sheets (2211); the plurality of pole ear sheets (2211) converge at a position close to the current collector (211) to form a first gathered portion (2212); the plurality of pole ear sheets (2211) converge at a position away from the current collector (211) and are connected to form a second gathered portion (2213); the first gathered portion (2212) connects the second gathered portion (2213) and the active material coating portion (21); and at least a portion of the second gathered portion (2213) is accommodated in the second accommodation groove (12120).

27. The battery cell (10) according to claim 26, wherein: The accommodating portion (121) further comprises a third accommodating groove (12140); the surface of the first pole (12) facing the active material coating portion (21) is the pole inner end face (122); the third accommodating groove (12140) is located on the side of the second accommodating groove (12120) close to the active material coating portion (21); 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) via the first through hole (12130); and at least a portion of the first retracted portion (2212) is accommodated in the third accommodating groove (12140).

28. The battery cell (10) according to claim 26 or 27, wherein: The conductive part (22) further comprises a transfer plate (222), wherein the transfer plate (222) is connected to the second retracted part (2213), the conductive part (22) is electrically connected to the first pole (12) via the transfer plate (222), and at least a portion of the transfer plate (222) is accommodated in the second accommodation groove (12120).

29. The battery cell (10) according to any one of claims 12 to 24, wherein: The active material coating portion (21) comprises a current collector (211) and an active material layer (212) disposed on the current collector (211); the conductive portion (22) comprises a pole ear portion (221) and a transfer sheet (222); the pole ear portion (221) comprises a plurality of pole ear sheets (2211) electrically connected to the current collector (211); a plurality of pole ear sheets (2211) converge at positions close to the current collector (211) to form a first gathered portion (2212); a plurality of pole ear sheets (2211) converge at positions away from the current collector (211) and are connected to form a second gathered portion (2213); the transfer sheet (222) is electrically connected to the second gathered portion (2213); at least a portion of the transfer sheet (222) is accommodated in the second accommodation groove (12120) and is electrically connected to the first pole (12).

30. The battery cell (10) according to claim 1, 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 by the first pole (12).

31. The battery cell (10) according to claim 1-7, 12-25 or 30, 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).

32. The battery cell (10) according to claim 31, 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).

33. The battery cell (10) according to claim 31 or 32, wherein: The bracket (3) is provided with a third groove (38), and at least part of the first pole (12) located in the housing (11) is accommodated in the third groove (38).

34. The battery cell (10) according to any one of claims 31 to 33, wherein: The avoidance hole (31) comprises a first hole segment (311) and a second hole segment (312), the second hole segment (312) being 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), the active material coating portion (21) comprises a current collector (211) and an active material layer (212) disposed on the current collector (211), the conductive portion (22) comprises a pole ear portion (221) electrically connected to the current collector (211), the pole ear portion (221) The invention comprises a plurality of pole lugs (2211), wherein the plurality of pole lugs (2211) converge at positions close to the current collector (211) to form a first gathered portion (2212), and the plurality of pole lugs (2211) converge at positions away from the current collector (211) and are connected to form a second gathered portion (2213), wherein the first gathered portion (2212) connects the second gathered portion (2213) and the active material coating portion (21), wherein at least a portion of the first gathered portion (2212) is accommodated in the second hole segment (312), and the second gathered portion (2213) is penetrated through the first hole segment (311).

35. The battery cell (10) according to any one of claims 31 to 34, 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).

36. The battery cell (10) according to any one of claims 31 to 35, 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).

37. The battery cell (10) according to any one of claims 1 to 36, wherein: The housing assembly (1) comprises a plurality of poles, at least one of the poles being the first pole (12).

38. The battery cell (10) according to claim 37, wherein: The shell (11) has a pressure relief portion (16), and the pressure relief portion (16) and the pole are located on the same side surface of the shell (11); or the pressure relief portion (16) and the pole are located on two surfaces on different sides of the shell (11).

39. The battery cell (10) according to any one of claims 1 to 38, wherein: The shell (11) is provided with a pressure relief portion (16). The shell (11) comprises a shell body (111) and a shell cover (112). One end of the shell body (111) is open. The shell cover (112) is arranged at the open end of the shell body (111). The pressure relief portion (16) is arranged on the shell cover (112).

40. A battery (100), wherein: The invention comprises a battery cell (10) according to any one of claims 1 to 39.

41. An electrical device (1000), wherein: Comprising a battery (100) according to claim 40.

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