Battery cells, batteries and electrical devices

Abstract

The present invention relates to a battery cell, a battery, and an electric device, which are related to the technical field of batteries. The battery cell includes a pole and a battery core assembly, and the battery core assembly includes an active material-coated portion and a plurality of tab sheets extending from the active material-coated portion in a first direction, wherein ends of the tab sheets adjacent to the active material-coated portion converge to form a first converging portion, ends of the tab sheets away from the active material-coated portion converge and connect to form a second converging portion, the first converging portion is connected to the second converging portion and the active material-coated portion, and an orthogonal projection of the end of the second converging portion connected to the first converging portion on the pole along the first direction is at least partially located within the outer contour range of the pole. This battery cell is advantageous for shortening the length of the conductive portion and improving the reliability of the battery cell.

Description

[Technical Field]

[0001] This application relates to the technical field of batteries, and more particularly to battery cells, batteries, and electrical devices. [Background technology]

[0002] In recent years, new energy vehicles have made great strides in development, and in the field of electric vehicles, batteries play an irreplaceable and important role as the power source for electric vehicles. Batteries typically contain multiple battery cells, but the reliability of current battery cells needs to be improved. Summary of the Invention

[0003] Embodiments of the present application provide battery cells, batteries, and electrical devices that are advantageous in improving the reliability of battery cells.

[0004] In a first aspect, an embodiment of the present application provides a battery cell including a casing assembly and a battery core assembly, wherein the casing assembly includes a casing and a pole mounted in the casing, and the battery core assembly includes an active material application portion and a conductive portion, the conductive portion being electrically connected to the active material application portion and the pole, and the conductive portion including a plurality of tab sheets extending from the active material application portion along a first direction, wherein one ends of the plurality of tab sheets close to the active material application portion converge to form a first converging portion, and one ends of the plurality of tab sheets away from the active material application portion converge and connect to form a second converging portion, the first converging portion is connected to the second converging portion and the active material application portion, and an orthogonal projection of an end of the second converging portion connected to the first converging portion on the pole along the first direction is at least partially located within an outer contour range of the pole.

[0005] In the above technical solution, the ends of the tab sheets away from the active material-coated portions are converged and connected to form a second convergent portion, and at least a portion of the orthogonal projection of the end of the second convergent portion connected to the first convergent portion on the electrode pole along the first direction is located within the outer contour range of the electrode pole. This advantageously reduces the length of the second convergent portion in the direction perpendicular to the first direction so that at least a portion of the second convergent portion is within the outer contour range of the electrode pole after extending from the end, thereby facilitating electrical connection of the conductive portion to the electrode pole. On the other hand, this advantageously reduces the overall length of the conductive portion, which not only reduces the cost of the conductive portion but also alleviates the problem of reverse insertion due to the redundancy of the conductive portion, thereby improving the reliability of the battery cell. Furthermore, this type of installation can further concentrate the space occupied by the conductive part and the electrode post in the direction perpendicular to the first direction, reducing the overall space occupied by both of them, thereby freeing up the remaining space of the battery cell in the direction perpendicular to the first direction, allowing other structures to be laid out, such as an insulating structure to further improve the reliability of the battery cell, or allowing more electrolyte to be accommodated to ensure the cycle life of the battery cell.

[0006] In some embodiments, the orthogonal projections on a polar cylinder along the first direction of the ends where the second convergent section is connected to the first convergent section all lie within the outer contour range of the polar cylinder.

[0007] In the above technical solution, the orthogonal projections of the end of the second converging portion connected to the first converging portion on the pole along the first direction are all located within the outer contour range of the pole, which is advantageous to shorten the distance from the end of the conductive portion to the pole in the direction perpendicular to the first direction, further shorten the length of the conductive portion, further reduce the redundancy and cost of the conductive portion, and further improve the reliability of the battery cell.

[0008] In some embodiments, the orthogonal projections of the second converging portion on a polar cylinder along the first direction are all located within the outer contour range of the polar cylinder.

[0009] In the above technical solution, the orthogonal projections of the second converging portion on the pole along the first direction are all located within the outer contour range of the pole, which is advantageous to shorten the distance from the second converging portion of the conductive portion to the pole in the direction perpendicular to the first direction, further shorten the length of the conductive portion, further reduce the redundancy and cost of the conductive portion, and further improve the reliability of the battery cell.

[0010] In some embodiments, an orthogonal projection of the first convergence portion on a polar cylinder along the first direction lies at least partially within an outer contour range of the polar cylinder.

[0011] In the above technical solution, by locating at least a part of the orthogonal projection of the first converging portion on the pole along the first direction within the outer contour range of the pole, it is advantageous to shorten the distance from the first converging portion to the pole in a direction perpendicular to the first direction, which can further shorten the length of the conductive portion, further reduce the redundancy and cost of the conductive portion, and further improve the reliability of the battery cell.

[0012] In some embodiments, the conductive portions are multiple, and an orthogonal projection of an end of each conductive portion where the second converging portion is connected to the first converging portion on a polar pillar along the first direction is at least partially located within an outer contour range of the polar pillar.

[0013] In the above technical solution, at least a portion of the orthogonal projection of the end of each conductive part where the second converging part is connected to the first converging part on the pole along the first direction is located within the outer contour range of the pole, which can more fully and effectively shorten the distance from the end of each conductive part to the pole, thereby more fully reducing the redundancy and cost of the conductive parts and is beneficial to further improving the reliability of the battery cell.

[0014] In some embodiments, the orthogonal projection on the polar pillar along the first direction of the end at which the second converging section is connected to the first converging section is positioned eccentrically relative to the polar pillar.

[0015] In the above technical solution, the orthogonal projection of the end of the second convergent portion connected to the first convergent portion on the pole along the first direction is positioned eccentrically relative to the pole, thereby increasing the area of ​​the portion of the pole that is electrically connected to the conductive portion, improving the area of ​​the pole that is electrically connected to the conductive portion, and thus improving the current-passing ability of the electrical connection, which is beneficial to improving charging efficiency.

[0016] In some embodiments, the conductive portion is used to connect the second converging portion and the polar pole, and the orthogonal projection on the polar pole along the first direction further includes an adapter sheet at least partly located within the outer contour range of the polar pole.

[0017] In the above technical solution, by orthogonally projecting the adapter sheet onto a projection plane perpendicular to the first direction, at least a portion of the orthogonal projection of the adapter sheet on the projection plane is located within the range defined by the orthogonal projection profile of the electrode post on the projection plane, thereby shortening the length of the adapter sheet, reducing adapter sheet costs and redundancy, and reducing the space occupied by the adapter sheet within the casing. Furthermore, by using the adapter sheet to achieve an indirect electrical connection between the second converging portion and the electrode post, the adapter sheet can be welded to the electrode post using a portion that avoids the second converging portion, resulting in reliable welding between the adapter sheet and the electrode post and reducing the risk of weld cracking, further improving the reliability and stability of the battery cell. At the same time, electrically connecting the electrode post and the tab sheet via the adapter sheet also simplifies the tab sheet structure.

[0018] In some embodiments, the pole post has a receiving portion, and at least a portion of the conductive portion is received in the receiving portion.

[0019] In the above technical solution, on the one hand, a housing is provided on at least one electrode post, and when the housing is located on the side of the electrode post away from the active material-coated portion, the portion of the conductive part located within the housing can be welded to the electrode post from outside the casing via the housing. When the housing is located on the side of the electrode post facing the active material-coated portion, the electrode post has a local thin wall corresponding to the housing, and when the housing is located on the side of the electrode post facing the active material-coated portion, the portion of the conductive part housed within the housing can be welded to the electrode post from the thinned portion from outside the casing. Therefore, even if the length of the conductive part located within the casing is relatively short, welding between the conductive part and the electrode post can be performed from outside the casing, which makes welding between the conductive part and the electrode post easier and improves the reliability of the welding between the conductive part and the electrode post. On the other hand, providing a housing on the electrode post can reduce the weight of the electrode post to some extent, thereby improving the weight-energy density of the battery cell and the battery. On the other hand, by accommodating at least a portion of the conductive portion within the accommodating portion so that it occupies space within the electrode post, the space occupied by the conductive portion within the casing can be reduced. For a given casing size, this saves space that would otherwise be required to accommodate a larger active material coated portion within the casing, thereby improving the volumetric energy density of the battery cell. At the same time, by accommodating at least a portion of the conductive portion within the accommodating portion, the space occupied by the battery cell itself can be reduced, allowing more battery cells to be accommodated in a battery with the same volume, thereby further improving the volumetric energy density of the battery. Furthermore, by accommodating at least a portion of the conductive portion within the accommodating portion, the redundancy of the conductive portion within the casing can be reduced to some extent, reducing the probability of short-circuiting between the conductive portion and the active material coated portion and the electrode assembly, thereby improving the operational reliability and stability of the battery cell and battery.

[0020] In some embodiments, at least a portion of the second converging portion is accommodated in the accommodating portion, and / or the conductive portion further includes an adapter sheet for connecting the second converging portion and the pole, and at least a portion of the adapter sheet is accommodated in the accommodating portion.

[0021] In the above technical solution, on the one hand, by accommodating at least a portion of the second converging portion within the receiving portion, the connection between the conductive portion and the electrode post is facilitated, the space within the electrode post is fully utilized, and the volumetric energy density of the battery cell is improved. On the other hand, by accommodating at least a portion of the adapter sheet within the receiving portion, the space within the electrode post is fully utilized, reducing the space occupied by the conductive portion within the casing and improving the volumetric energy density of the battery cell. Furthermore, by using the adapter sheet to achieve an indirect electrical connection between the second converging portion and the electrode post, the adapter sheet can be welded to the electrode post using a portion that avoids the second converging portion. This improves the reliability of the welding between the adapter sheet and the electrode post, making it less susceptible to weld cracking, and further improving the reliability and stability of the battery cell. At the same time, the electrical connection between the electrode post and the tab sheet via the adapter sheet also simplifies the tab sheet structure.

[0022] In some embodiments, at least a portion of the first converging portion is housed within the housing.

[0023] In the above technical solution, at least a portion of the first converging portion is accommodated in the accommodating portion, thereby making better use of the space within the pole, further reducing the space occupied by the tab sheet within the casing, and improving the volumetric energy density of the battery cell.

[0024] In some embodiments, the accommodating portion has a first accommodating groove, the surface of the pole facing the active material coated portion is the pole inner end face, the groove opening of the first accommodating groove is formed in the pole inner end face, and at least a portion of the conductive portion is accommodated in the first accommodating groove.

[0025] In the above technical solution, on the one hand, by forming a first accommodating groove in the electrode post, it is possible to reduce the weight of the electrode post to some extent and improve the weight energy density of the battery cell and battery. On the other hand, because the groove opening of the first accommodating groove is formed on the inner end surface of the electrode post, which is the side surface adjacent to the active material coating portion of the electrode post, the first accommodating groove is open toward the active material coating portion, which in turn makes it easier for the conductive portion to extend into the first accommodating groove, improving assembly efficiency. At the same time, because the first accommodating groove faces the active material coating portion, it can also serve as a buffering and temporary storage structure for electrolyte, allowing more electrolyte to be accommodated in the casing. This allows for longer service life for the battery cell, since electrolyte is consumed during the charging and discharging process of the battery cell. Furthermore, because the first accommodating groove faces the active material coating portion, it can also serve as a buffering structure for gas generated inside the electrode assembly, reducing expansion of the battery cell and improving the reliability and stability of the battery cell. Furthermore, the first accommodating groove is located inside the electrode post, making it difficult for external foreign matter to enter the first accommodating groove, thereby reducing the impact of external foreign matter on the electrode assembly and ensuring the stability and reliability of the operation of the electrode assembly, thereby improving the stability and reliability of the battery cell and battery.

[0026] In some embodiments, the casing has a mounting hole, and the pole is mounted in the mounting hole. The depth of the first receiving groove along the first direction is equal to or greater than the minimum distance from the inner end surface of the pole to the mounting hole.

[0027] In the above technical solution, the depth of the first accommodating groove in the first direction is equal to or greater than the minimum distance from the inner end surface of the electrode post to the mounting hole, thereby fully utilizing the volume of the electrode post. Therefore, the first accommodating groove has a relatively large depth, which is advantageous for accommodating more conductive parts, thereby significantly reducing the space occupied by the conductive parts in the casing, further improving the energy density of the battery cell and further reducing the redundancy of the conductive parts in the casing. At the same time, the relatively large depth of the first accommodating groove also allows it to accommodate gas generated by the electrode assembly, ensuring the reliability and stability of the battery cell, and can accommodate more electrolyte, thereby ensuring the service life of the battery cell.

[0028] In some embodiments, the electrode post includes a first end wall and a first side wall, the first end wall being located on a side of the first side wall away from the active material application portion, the first end wall and the first side wall surrounding each other forming a first accommodating groove, and the position where the conductive portion is electrically connected to the electrode post is located on the first end wall and / or the first side wall.

[0029] In the above technical solution, by locating the position where the conductive part is electrically connected to the pole on at least one of the first end wall and the first side wall, the first receiving groove not only accommodates at least a portion of the conductive part but also realizes the electrical connection with the conductive part, thereby simplifying the structure of the pole, facilitating processing of the pole, simplifying the structure of the conductive part, reducing the redundancy of the conductive part, and reducing the cost of the conductive part. Furthermore, by utilizing the groove wall of the first receiving groove to realize the electrical connection with the conductive part, a relatively large electrical connection area between the conductive part and the pole can be provided, which not only reduces the difficulty of the electrical connection but also improves the reliability and stability of the electrical connection, thereby improving the performance of the battery cell.

[0030] In some embodiments, the first end wall has a first recessed groove, and at least a portion of the electrical connection location between the conductive portion and the first end wall is located within the first recessed groove.

[0031] In the above technical solution, on the one hand, by providing the first recessed groove in the first end wall, the conductive part can be pre-positioned using the first recessed groove, which is advantageous for achieving accurate positioning and electrical connection, and improving production efficiency. On the other hand, by providing the first recessed groove in the first end wall, the thickness of the first end wall can be locally thinned, which is not only advantageous for electrical connection by welding, but also advantageous for reducing the weight of the pole and improving the weight-energy density of the battery cell.

[0032] In some embodiments, the electrode post has a first groove, the surface of the electrode post away from the active material coated portion is the electrode post outer end face, and the groove opening of the first groove is formed in the electrode post outer end face.

[0033] In the above technical solution, on the one hand, the provision of the first groove in the electrode post can further reduce the weight of the electrode post to improve the weight energy density of the battery cells and the battery. On the other hand, the first groove is located on the outside of the electrode post, and the first groove can be used to accommodate or attach structural components that electrically connect each battery cell in the battery, making full use of the space within the electrode post and improving the space utilization rate and volumetric energy density of the battery. In addition, the electrode post also has a first receiving groove and a second receiving groove, and the first groove is located on the side away from the active material coated portion of the first receiving groove and is open in a direction away from the first receiving groove. This is advantageous for electrically connecting the conductive part to the groove wall of the first receiving groove from the outside of the electrode post through the first groove, for example, making it convenient to externally weld the electrode post and the conductive part through the first groove, which facilitates the processing and manufacturing of the battery cell and reduces processing and manufacturing costs.

[0034] In some embodiments, the casing assembly further includes a groove cover provided on the pole and sealingly capping the groove opening of the first groove.

[0035] In the above technical solution, the installation of the groove cover facilitates the electrical connection between adjacent battery cells within the battery, and the electrical connection positions between the conductive parts and the poles are separated by the first groove, which reduces interference between the two and further improves the stability and reliability of the battery cells. At the same time, the groove cover prevents foreign objects from entering the first groove, reducing interference between external foreign objects and the battery core assembly, further improving the reliability and stability of the battery cells.

[0036] In some embodiments, at least a portion of the second converging portion is received within the first receiving groove.

[0037] In the above technical solution, the tab portion includes a second converging portion formed by gathering and connecting multiple tab sheets, so that at least a portion of the second converging portion is accommodated in the first accommodating groove, which facilitates the connection between the conductive portion and the electrode post, makes full use of the space in the electrode post, and improves the volumetric energy density of the battery cell.

[0038] In some embodiments, at least a portion of the first converging portion is received in the first receiving groove.

[0039] In the above technical solution, at least a portion of the first converging portion of the tab portion and at least a portion of the second converging portion are both accommodated in the first accommodating groove, thereby making better use of the space within the pole, further reducing the space occupied by the tab portion within the casing, and improving the volumetric energy density of the battery cell.

[0040] In some embodiments, the conductive portion further includes an adapter sheet for connecting the second converging portion and the pole post, at least a portion of the adapter sheet being received in the first receiving groove.

[0041] In the above technical solution, on the one hand, by using an adapter sheet to realize an indirect electrical connection between the second converging portion and the electrode post, the adapter sheet can be welded to the electrode post using a portion that avoids the second converging portion. This makes the welding between the adapter sheet and the electrode post more reliable, less prone to weld cracking, and further improves the reliability and stability of the battery cell. At the same time, the electrode post and the tab portion are electrically connected via the adapter sheet, which simplifies the structure of the tab portion. On the other hand, because at least a portion of the adapter sheet is accommodated in the first accommodating groove, the adapter sheet can occupy more space within the electrode post, thereby reducing the space occupied by the adapter sheet within the casing, allowing a larger active material coating portion to be accommodated, improving the volumetric energy density of the battery cell, and reducing the probability of a short circuit between the adapter sheet and the active material coating portion. This reduces the risk of a short circuit in the electrode assembly and improves the stability and reliability of the battery cell.

[0042] In some embodiments, the accommodating portion has a second accommodating groove, the surface of the pole away from the active material coating portion is the pole outer end face, the groove opening of the second accommodating groove is formed on the pole outer end face, the second accommodating groove communicates with the inside of the casing through the first through hole, and the conductive portion is drilled in the first through hole and at least a portion of the conductive portion is accommodated in the second accommodating groove.

[0043] In the above technical solution, on the one hand, by providing the second accommodating groove in the electrode post, the weight of the electrode post can be reduced to a certain extent in order to improve the weight energy density of the battery cell and the battery. On the other hand, the groove opening of the second accommodating groove is formed on the outer end surface of the electrode post, which is the surface of the electrode post facing away from the active material coated portion, so that the second accommodating groove can open in the direction away from the active material coated portion. In this way, when at least a portion of the conductive portion is accommodated in the second accommodating groove, the groove opening of the second accommodating groove can easily accommodate and organize the conductive portion or operate the electrical connection between the conductive portion and the electrode post, thereby reducing the difficulty of battery cell production and improving battery cell production efficiency. At the same time, because the second accommodating groove can communicate with the casing through the first through-hole, the second accommodating groove also functions as a buffer and temporary storage structure for the electrolyte, allowing more electrolyte to be accommodated in the casing. Since the electrolyte is consumed during the charging and discharging process of the battery cell, the service life of the battery cell can be extended when there is more electrolyte. Furthermore, because the second accommodating groove can communicate with the casing through the first through-hole, the second accommodating groove also functions as a buffer and storage structure for gas generated inside the electrode assembly, reducing the expansion of the battery cell and improving the reliability and stability of the battery cell.

[0044] In some embodiments, the electrical connection position between the conductive portion and the electrode post is located on the hole wall of the first through hole formed by the electrode post.

[0045] In the above technical solution, when the electrical connection position between the conductive part and the electrode post is located on the wall of the first through-hole, the electrical connection between the conductive part and the electrode post can be performed through the second receiving groove, and the electrical connection position between the conductive part and the electrode post can also seal the first through-hole, saving sealing costs and reducing electrolyte leakage.

[0046] In some embodiments, the electrode post includes a second end wall and a second side wall, the second end wall being located on a side of the second side wall that is close to the active material application portion, the second end wall and the second side wall surrounding each other forming a second accommodating groove, the first through-hole being opened in the second end wall, and the electrical connection position between the conductive portion and the electrode post being located in the second end wall and / or the second side wall.

[0047] In the above technical solution, the location where the conductive portion is electrically connected to the electrode post is located on at least one of the second end wall and the second side wall. Therefore, the second accommodating groove not only accommodates at least a portion of the conductive portion, but also allows the groove wall of the second accommodating groove to establish electrical connection with the conductive portion, thereby simplifying the structure of the electrode post and facilitating its processing. Furthermore, the first through-hole is provided in the second end wall, allowing the conductive portion to easily extend into the second accommodating groove through the first through-hole, simplifying the structure of the conductive portion, reducing redundancy, and reducing the cost of the conductive portion. Furthermore, the opening direction of the second accommodating groove's groove opening facilitates the electrical connection between the conductive portion and the groove wall of the second accommodating groove through the groove opening of the second accommodating groove, thereby reducing the difficulty of the electrical connection. Furthermore, the electrical connection with the conductive portion is achieved using the groove wall of the second accommodating groove, thereby increasing the electrical connection area between the conductive portion and the electrode post, improving the reliability and stability of the electrical connection and ultimately improving the performance of the battery cell.

[0048] In some embodiments, the second end wall has a second recessed groove, and at least a portion of the electrical connection location between the conductive portion and the second end wall is located within the second recessed groove.

[0049] In the above technical solution, by installing a second recessed groove on the second end wall, the second recessed groove can be used to realize pre-positioning of the conductive part, allowing for accurate alignment and electrical connection, thereby improving production efficiency.

[0050] In some embodiments, the casing has a mounting hole, the pole is mounted in the mounting hole, and the depth of the second receiving groove along the first direction is equal to or greater than the minimum distance from the outer end surface of the pole to the mounting hole.

[0051] In the above technical solution, the depth of the second accommodating groove in the first direction is equal to or greater than the minimum distance from the outer end surface of the electrode post to the mounting hole, thereby fully utilizing the volume of the electrode post. Therefore, the second accommodating groove has a relatively large depth, which is advantageous for accommodating more conductive parts, thereby significantly reducing the space occupied by the conductive parts in the casing, further improving the energy density of the battery cell, and further reducing the redundancy of the conductive parts in the casing. At the same time, the relatively large depth of the second accommodating groove also allows it to accommodate gas generated by the electrode assembly, improving the reliability and stability of the battery cell, and further accommodating more electrolyte, thereby improving the service life of the battery cell.

[0052] In some embodiments, the casing assembly further includes a first cover plate that fits over the pole, seals the groove opening of the second receiving groove, and is electrically connected to the pole.

[0053] In the above technical solution, by installing the first cover plate to seal the opening of the second accommodating groove, it is possible to prevent the electrolyte in the casing from leaking out from the opening of the second accommodating groove. Furthermore, since the first cover plate seals the opening of the second accommodating groove and is electrically connected to the pole, it is possible to easily realize an indirect electrical connection between the pole and the bus member of the battery using the first cover plate, which is advantageous for increasing the connection area of ​​the electrical connection point and therefore reducing the resistance of the electrical connection point.

[0054] 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 being fitted to and electrically connected to the pole, and the second conductive member being fitted to and electrically connected to the first conductive member.

[0055] In the above technical solution, the first cover plate is installed in a composite form, and the first conductive member is installed with the same material as the pole, thereby facilitating the electrical connection between the first conductive member and the pole; and since the second conductive member and the first conductive member are made of different materials, the second conductive member is used to facilitate the electrical connection with the battery bus member made of a different material from the pole.

[0056] In some embodiments, the first conductive member has a second groove, the second conductive member is fitted into the second groove, and the groove opening of the second groove is formed on a surface of the first conductive member facing away from the second receiving groove so that the second conductive member is exposed from the groove opening of the second groove.

[0057] In the above technical solution, the second conductive member is fitted into the first conductive member, which simplifies assembly of the first and second conductive members, improves the stability and convenience of the mating of the first and second conductive members, and reduces the thickness of the first cover plate, reducing the space occupied by the first cover plate and improving the space utilization rate of the battery cell. On the other hand, the second conductive member can be exposed from the surface of the first conductive member facing away from the second receiving groove through the opening of the second groove, which is advantageous for achieving electrical connection between the second conductive member and the battery bus members outside the pole. Furthermore, because the opening of the second groove is formed on the surface of the first conductive member facing away from the second receiving groove, the first conductive member is isolated between the second receiving groove and the second conductive member, which prevents contact between the electrolyte in the second groove and the second conductive member and reduces electrolyte leakage.

[0058] In some embodiments, the first cover plate is fitted into the groove opening of the second receiving groove.

[0059] In the above technical solution, by fitting the first cover plate into the second accommodating groove, the difficulty of assembling the first cover plate and the electrode post can be reduced, the assembly stability and connection reliability and convenience between the first cover plate and the electrode post can be improved, and the space occupied by the first cover plate other than the electrode post can be reduced.In addition, because the first cover plate is fitted into the groove opening of the second accommodating groove, there can be a relatively sufficient space in the second accommodating groove to accommodate the conductive part.

[0060] In some embodiments, the wall surface of the pole pillar that forms the groove opening of the second receiving groove is a guide slope, and the guide slope is used to guide the fitting of the first cover plate with the groove opening of the second receiving groove.

[0061] In the above technical solution, by processing the wall surface of the groove opening of the second accommodating groove into a sloped surface with a guide function, the difficulty of assembling the first cover plate and the second accommodating groove can be reduced, and the assembly efficiency of the first cover plate and the second accommodating groove can be improved.

[0062] In some embodiments, the second receiving groove includes a first groove step and a second groove step on a side of the first groove step that is adjacent to the outer end surface of the pole post, the cross-sectional area of ​​the second groove step being larger than the cross-sectional area of ​​the first groove step so as to form a stepped surface between the first groove step and the second groove step, and the first cover plate is fitted into the second groove step and supported by the stepped surface.

[0063] In the above technical solution, by configuring the second accommodating groove in the form of a stepped groove, the first cover plate can be stably fitted into the groove opening of the second accommodating groove, improving the connection stability between the first cover plate and the pole; and by limiting the groove depth of the first groove step, a relatively sufficient space can be provided in the second accommodating groove to accommodate the conductive part.

[0064] In some embodiments, the first cover plate includes a stress relief groove located in a peripheral region of the first cover plate.

[0065] In the above technical solution, by installing a stress relief groove in the first cover plate, the stress generated in the first cover plate during its own processing or during the electrical connection process between the first cover plate and the pole can be released, thereby alleviating the problem of deformation or damage caused by stress on the first cover plate.

[0066] In some embodiments, the casing assembly further includes a second cover plate, which covers the first through hole and the conductive portion located in the second receiving groove.

[0067] In the above technical solution, when the electrolyte enters the second accommodating groove through the first through-hole, the second cover plate can solve the problem of the electrolyte in that portion overflowing from the pole, thereby improving the reliability of the battery cell.

[0068] In some embodiments, at least a portion of the second converging portion is received within the second receiving groove.

[0069] In the above technical solution, the tab portion includes a second converging portion formed by gathering and connecting multiple tab sheets, so that at least a portion of the second converging portion is accommodated in the second accommodating groove, facilitating assembly of the conductive part and the pole.

[0070] In some embodiments, the accommodating portion further has a third accommodating groove, the surface of the pole facing the active material applied portion is the pole inner end face, the third accommodating groove is located on the side of the second accommodating groove that is close to the active material applied portion, and the groove opening of the third accommodating groove is formed on the pole inner end face, the third accommodating groove and the second accommodating groove are connected by the first through hole, and at least a portion of the first converging portion is accommodated in the third accommodating groove.

[0071] In the above technical solution, at least a portion of the first converging portion of the tab portion is accommodated in the third accommodating groove, and at least a portion of the second converging portion is accommodated in the second accommodating groove, thereby making better use of the space within the pole post.

[0072] In some embodiments, the conductive portion further includes an adapter sheet for connecting the second converging portion and the pole, and at least a portion of the adapter sheet is received in the second receiving groove.

[0073] In the above technical solution, by accommodating at least a portion of the adapter sheet in the second accommodating groove, the adapter sheet can occupy space within the electrode post, thereby reducing the space occupied by the adapter sheet in the casing and accommodating a larger active material application portion, improving the energy density of the battery cell and reducing the probability of short-circuiting between the adapter sheet and the active material application portion. On the other hand, by using the adapter sheet to realize an indirect electrical connection between the second converging portion and the electrode post, the adapter sheet can be welded to the electrode post using a portion that avoids the second converging portion. This welding between the adapter sheet and the electrode post is reliable and less likely to cause weld cracks, further improving the reliability and stability of the battery cell. At the same time, by using the adapter sheet to realize the electrical connection between the tab portion and the electrode post, the structure of the tab portion can be simplified.

[0074] In some embodiments, the accommodating portion has a fourth accommodating groove, the surface of the pole facing away from the active material application portion is the pole outer end face, the groove opening of the fourth accommodating groove is formed on the pole outer end face, the fourth accommodating groove is connected to the inside of the casing via the second through hole, the conductive portion is drilled in the second through hole, and the electrical connection position between the conductive portion and the pole is located on the hole wall of the second through hole formed in the pole.

[0075] In the above technical solution, the provision of the fourth receiving groove can easily realize the electrical connection between the conductive part and the hole wall of the second through-hole, and in some cases, the electrical connection between the conductive part and the electrode post can realize the sealing of the second through-hole.

[0076] In some embodiments, the pole includes a first pole portion and a second pole portion made of different materials and electrically connected, the second pole portion being located on the side of the first pole portion away from the active material application portion, the accommodating portion being installed on the first pole portion or the first pole portion and the second pole portion, and the conductive portion being electrically connected to the first pole portion.

[0077] In the above technical solution, the poles are arranged in a composite form using a combination of different materials, utilizing the fitting and electrical connection between the first pole part located on the inside and the conductive part, and the electrical connection between the second pole part located on the outside and the bus parts of the battery, etc., which is advantageous for assembling and electrically connecting the poles and related parts, reduces the number of electrical connection positions between the poles and the conductive parts, and reduces mutual interference between the electrical connection positions between the poles and the bus parts of the battery, thereby improving the reliability and stability of the battery cell.

[0078] In some embodiments, the battery cell further includes a support located within the casing and positioned on a side of the active material application portion that is adjacent to the pole, the support having an escape hole for avoiding the conductive portion, the conductive portion adapted to extend through the escape hole to a side of the support that is away from the active material application portion.

[0079] In the above technical solution, by providing an escape hole in the support, the conductive part can be guided and restrained so that it passes through the escape hole and fits into the pole, which not only simplifies the arrangement of the conductive part, saves on the material used for the conductive part, and reduces costs, but also supports and guides the fit between the conductive part and the pole via the support, reduces the risk of short-circuiting between the conductive part and the active material coated part, and further improves the reliability of the battery cell.

[0080] In some embodiments, the battery cell further includes a support located within the casing and positioned on a side of the active material application portion closest to the pole, the support having an escape hole for avoiding the conductive portion, the conductive portion adapted to extend through the escape hole to a side of the support away from the active material application portion, and a guide portion provided on the support, the guide portion surrounding the escape hole and forming at least a portion of the escape hole, and at least a portion of the guide portion extending into the accommodation portion.

[0081] In the above technical solution, the provision of relief holes in the support allows the conductive part to be guided and restrained so that it passes through the relief holes and fits into the electrode post, simplifying the arrangement of the conductive part, saving material for the conductive part, and reducing costs. The support also supports and guides the fit between the conductive part and the electrode post, reducing the risk of short-circuiting between the conductive part and the active material-coated part, further improving the reliability of the battery cell. The support has a guide part, at least a portion of which extends into the receiving part, and the guide part surrounds and forms at least a portion of the relief hole, making it easier to fit at least a portion of the conductive part into the receiving part and improving the assembly efficiency of the conductive part. At the same time, the provision of the guide part provides a tighter and more reliable fit between the support and the electrode post and between the support and the conductive part, making the battery cell structure more compact and further improving the energy density of the battery cell.

[0082] In some embodiments, the support is provided with a third recess, and at least a portion of the pole positioned inside the casing is received in the third recess.

[0083] In the above technical solution, the third groove is provided in the support to accommodate at least a portion of the portion of the electrode post located within the casing. This is advantageous for reducing the space occupied by the support within the casing, and for improving the stability and reliability of the electrode post, ensuring the reliability and stability of the electrical connection between the electrode post and the battery core assembly, and improving the reliability and stability of the charging and discharging operations of the battery cell.

[0084] In some embodiments, the relief hole includes a first hole section and a second hole section, the second hole section being located on a side of the first hole section that is closer to the active material application portion, and the cross-sectional area of ​​the second hole section gradually increases in a direction away from the first hole section, at least a portion of the first converging portion is accommodated within the second hole section, and the second converging portion is drilled in the first hole section.

[0085] In the above technical solution, the escape hole is configured to include a second hole section that gradually widens toward the active material application section, making it easier for the second hole section to accommodate more of the first converging section, improving the compactness of the fit between the support and the battery core assembly, reducing the overall volume of the battery cells, allowing the battery to accommodate more battery cells, and improving the volumetric energy density of the battery.

[0086] In some embodiments, the support is a unitary structure, or the support includes a first support and a second support that are separate and removable, with a relief hole defined between the first support and the second support.

[0087] In the above technical solution, if the support has an integral structure, the support can be easily processed, its reliability is relatively good, and the assembly of the support and the casing assembly is easy, improving assembly efficiency and fitting stability. If the support has a separate structure, an escape hole is defined by the engagement of the first support and the second support, and when assembling the support and the battery core assembly, there is no need to pass the conductive part from one end to the other of the escape hole. Instead, the first support and the second support can be combined at the position of the conductive part to sandwich the conductive part, so that the escape hole surrounds the conductive part, making it easy to assemble the support and the battery core assembly and improving assembly efficiency.

[0088] In some embodiments, the battery cell further includes an inner insulating member located within the casing, surrounding the outside of the active material coating portion, and connected to the support.

[0089] In the above technical solution, on the one hand, by wrapping the inner insulating member around the outside of the active material application portion, the reliability of insulation between the active material application portion and the casing is improved, the occurrence of casing corrosion due to contact between the active material application portion and the casing is reduced or prevented, and the problem of electrolyte leakage due to casing corrosion is reduced, thereby improving the reliability of the battery cell; on the other hand, by connecting the inner insulating member to the support, the difficulty of fixing the inner insulating member is reduced, and the reliability of the inner insulating member wrapping around the outside of the active material application portion is improved.

[0090] In some embodiments, the casing has a pressure relief portion, and the pressure relief portion and the pole are located on the same surface of the casing, or the pressure relief portion and the pole are located on two surfaces on different sides of the casing.

[0091] In the above technical solution, if the electrode post and the pressure relief part are installed on the same side, processing and assembly are facilitated; if the electrode post and the pressure relief part are installed on different sides, space can be saved, the volume of the electrode post can be increased, and the adverse effect on the electrode post when the pressure relief part releases pressure can be reduced.

[0092] In some embodiments, the casing has a pressure relief portion, the casing includes a casing body and a casing cover, one end of the casing body is open, the casing cover is provided at the open end of the casing body, and the pressure relief portion is provided at the casing cover.

[0093] In the above technical solution, the pressure relief part is easy to process and has high pressure relief reliability.

[0094] In a second aspect, embodiments of the present application further provide a battery including the battery cell described above.

[0095] In the above technical solution, the battery cell is arranged in a manner that is advantageous for shortening the distance from the end of the conductive part to the pole in the direction perpendicular to the first direction, allowing the second converging part to be arranged relatively close to the pole, thereby facilitating direct or indirect welding between the tab sheet and the pole, ensuring the reliability of the welding between the conductive part and the pole, and further ensuring the reliability of the battery cell and the battery. It is also advantageous for shortening the overall length of the conductive part, which not only reduces the cost of the conductive part but also alleviates the problem of reverse insertion due to the redundancy of the conductive part, thereby further improving the reliability of the battery cell and the battery.

[0096] In a third aspect, embodiments of the present application further provide an electrical device comprising the battery described above.

[0097] In the above technical solution, the reliability of the battery can be improved by installing the battery in an electrical device, and thus the reliability of the electrical device can be improved. [Brief explanation of the drawings]

[0098] In order to more clearly explain the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings used in the embodiments. However, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope. Those skilled in the art can obtain other related drawings based on these drawings without any creative work. [Figure 1] 1 is a structural schematic diagram of a battery cell provided by some embodiments of the present application; [Figure 2] 1 is an exploded view of a battery structure provided in accordance with some embodiments of the present application. [Figure 3] 1 is a structural schematic diagram of a battery cell provided by some embodiments of the present application; [Figure 4] FIG. 1 is an orthographic view of a battery cell provided in accordance with some embodiments of the present application. [Figure 5] FIG. 5 is a cross-sectional view taken along the line AA in FIG. [Figure 6]FIG. 5 is an orthogonal projection schematic diagram of the F region of FIG. 4. [Figure 7] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 8] 1 is a schematic cross-sectional view of a battery core assembly provided in accordance with some embodiments of the present application. [Figure 9] 1 is a diagram illustrating a convergence scheme for multiple types of tabs in a battery core assembly provided by some embodiments of the present application. [Figure 10] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 11] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 12] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 13] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 14] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 15] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 16] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 17] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 18] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 19] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 20] FIG. 4 is an enlarged view of a portion B in FIG. 3. [Figure 21] 1A-1C are orthographic views of various polar pillars provided by some embodiments of the present application. [Figure 22] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 23]1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 24] 1 is an exploded view of a battery cell structure provided in accordance with some embodiments of the present application. [Figure 25] 1 is a schematic cross-sectional view of a casing assembly provided in accordance with some embodiments of the present application. [Figure 26] FIG. 26 is an exploded structural view of the casing assembly shown in FIG. 25. [Figure 27] FIG. 27 is an exploded view of the first cover plate shown in FIG. 26. [Figure 28] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 29] FIG. 29 is an exploded view of the structure of the battery cell shown in FIG. 28. [Figure 30] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 31] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 32] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 33] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 34] 1 is a schematic diagram of a battery core assembly and a support mating provided by some embodiments of the present application. [Figure 35] FIG. 35 is a cross-sectional view taken along line CC in FIG. [Figure 36] 1 is a structural schematic diagram of an integral support provided by some embodiments of the present application. [Figure 37] 1 is a structural schematic diagram of a separate support provided by some embodiments of the present application. [Figure 38] 1 is a schematic cross-sectional view of a battery core assembly and support provided by some embodiments of the present application. [Figure 39] 1 is an exploded structural view of a battery core assembly, support, and casing assembly provided in accordance with some embodiments of the present application. [Figure 40] 1 is an exploded view of the structure of a first pole, a casing, and a seal pad provided in some embodiments of the present application. FIG. [Figure 41] FIG. 41 is an assembly diagram of the first pole, casing, and seal pad shown in FIG. 40. [Figure 42] 1 is a structural schematic diagram of a first pole pillar provided by some embodiments of the present application; [Figure 43] 1 is an assembly diagram of a first pole, a casing, and a seal pad provided in accordance with some embodiments of the present application. [Figure 44] FIG. 44 is an exploded view of the structure of the first pole pillar shown in FIG. 43. [Figure 45] FIG. 1 is an orthographic view of a battery cell provided in accordance with some embodiments of the present application. [Figure 46] FIG. 1 is an orthographic view of a battery cell provided in accordance with some embodiments of the present application. [Figure 47] FIG. 47 is a cross-sectional view taken along line DD in FIG. 46. [Figure 48] 1 is a cross-sectional schematic view of a casing assembly provided in accordance with some embodiments of the present application. [Figure 49] 1 is a cross-sectional schematic view of a casing assembly provided in accordance with some embodiments of the present application. [Figure 50] FIG. 1 is an orthographic view of a battery cell provided in accordance with some embodiments of the present application. [Figure 51] FIG. 51 is a cross-sectional view taken along line EE in FIG. 50. [Figure 52] 1 is a schematic cross-sectional view of a battery cell provided in accordance with some embodiments of the present application. [Figure 53] 1 is a structural schematic diagram of a casing cover provided by some embodiments of the present application; [Figure 54]1 is a schematic diagram of a battery cell provided by some embodiments of the present application. [Explanation of symbols] battery cell 10, casing assembly 1, casing 11, first wall 110, casing body 111, casing cover 112, mounting hole 113, pole 12, accommodating portion 121, first accommodating groove 12110, first end wall 12111, first sunken groove 12112, first side wall 12113, second accommodating groove 12120, second end wall 12121, second sunken groove 12122, second side wall 12123, first groove step 12124, second groove step 12125, guide slope 12126, stepped surface 12127, first through hole 12130, third accommodating groove 12140, fourth accommodating groove 12150, second through-hole 12160, third through-hole 12170, electrode post inner end surface 122, electrode post outer end surface 123, first electrode post portion 124, second electrode post portion 125, first groove 126, spacing portion 127, stopper portion 1281, perforated 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 relaxation groove 133, second cover plate 14, pressure release portion 16, relief groove 18, first seal pad 191, second seal pad 192, battery core assembly 2, electrode assembly 2a, active material applied portion 21, conductive portion 22, current collector 211, active material layer 212, Tab portion 221, tab sheet 2211, first converging portion 2212, second converging portion 2213, connecting section 22130, first connecting section 22131, second connecting section 22132, end portion 2214, adapter sheet 222, support 3, escape hole 31, first hole section 311, second hole section 312, guide section 32, first support 33, second support 34, casing guide surface 35, main body portion 36, extension portion 37, third groove 38, positioning groove 39, inner insulating member 4, main body portion 41, connecting section 42, sealing member 6, groove cover 7, case 20, first case 201, second case 202, electric device 1000, battery 100, controller 200, motor 300, first direction Z, second direction X, third direction Y. DETAILED DESCRIPTION OF THE INVENTION

[0099] In order to clarify the objectives, technical solutions and advantages of the embodiments of the present application, the technical solutions of the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, but it is obvious that the described embodiments are only some of the embodiments of the present application, and do not represent all of the embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without any creative work also fall within the scope of protection of the present application.

[0100] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of this application, and the terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit this application, and the terms "comprises" and "has" and any variations thereof in the specification, claims, and drawings of this application are intended to cover a non-exclusive inclusion. Terms such as "first," "second," etc. in the specification, claims, and drawings of this application are used to distinguish between different objects and are not used to describe a particular order or priority.

[0101] In this application, a reference to an "embodiment" means 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 appearances of the phrase in various places in the specification do not necessarily refer to the same embodiment, nor are they mutually exclusive independent or alternative embodiments of other embodiments.

[0102] The term "and / or" in this application is simply a relational relationship that describes related objects, and indicates that three types of relationships can exist. For example, A and / or B can represent three cases: the presence of only A, the simultaneous presence of A and B, and the presence of only B. In addition, the symbol " / " in this application generally indicates that the related objects before and after it are in an "or" relationship.

[0103] In the embodiments of the present application, the same drawing symbols represent the same components, and for the sake of brevity, detailed descriptions of the same components will be omitted in different embodiments. It should be understood that the dimensions such as thickness, length, width, etc. of various components in the embodiments of the present application shown in the accompanying drawings, and the overall thickness, length, width, etc. of the integrated device, are merely exemplary and should not be construed as limitations of the present application.

[0104] The term "plurality" as used herein refers to two or more (including two).

[0105] In this application, the battery cell may include a lithium ion secondary battery, a lithium ion primary battery, a lithium-sulfur battery, a sodium lithium ion battery, a sodium ion battery, or a magnesium ion battery, etc., but the embodiments of this application are not limited thereto. The battery cell may be cylindrical, flat, rectangular, or have other shapes, etc., but the embodiments of this application are not limited thereto. Battery cells are generally classified into three types depending on the encapsulation method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, but the embodiments of this application are not limited thereto.

[0106] The battery referred to in the embodiments of this application refers to a single physical module containing 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 a battery pack. A battery module generally includes multiple battery cells. A battery pack generally includes a case for enclosing one or more battery cells or one or more battery modules. The case can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells.

[0107] For example, a battery cell typically includes a casing, a battery core assembly, and an electrolyte, where the casing is used to house the battery core assembly and the electrolyte, and at least one positive electrode post and at least one negative electrode post are provided in the casing. The battery core assembly includes one or more electrode assemblies, and the electrode assemblies are formed by stacking or winding positive electrode pieces, negative electrode pieces, and separator films.

[0108] The positive electrode piece generally includes a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer being directly or indirectly coated on the positive electrode current collector, the portion of the positive electrode current collector not coated with the positive electrode active material layer protruding from the portion of the positive electrode current collector coated with the positive electrode active material layer, the portion of the positive electrode current collector not coated with the positive electrode active material layer being a positive electrode tab sheet, and multiple positive electrode tab sheets are stacked and electrically connected to the positive electrode post. For example, multiple stacked positive electrode tab sheets can be directly welded to the positive electrode post to form the electrical connection, or the battery core assembly can include a positive electrode adapter sheet, and the multiple stacked positive electrode tab sheets can be welded to one end of the positive electrode adapter sheet and the other end of the positive electrode adapter sheet to electrically connect the positive electrode tab sheet and the positive electrode post.

[0109] The negative electrode piece generally includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is directly or indirectly coated on the negative electrode current collector. The negative electrode current collector without the negative electrode active material layer protrudes from the negative electrode current collector with the negative electrode active material layer coated thereon. The positive electrode current collector without the negative electrode active material layer serves as a negative electrode tab sheet. Multiple negative electrode tab sheets are stacked together and electrically connected to the negative electrode post. For example, the multiple stacked negative electrode tab sheets can be directly welded to the negative electrode post to form the electrical connection. Alternatively, the battery core assembly can include a negative electrode adapter sheet. The multiple stacked negative electrode tab sheets are welded to one end of the negative electrode adapter sheet and the other end of the negative electrode adapter sheet is welded to the negative electrode post to electrically connect the negative electrode tab sheet and the negative electrode post. The material of the separator film is not particularly limited and may be, for example, polypropylene or polyethylene.

[0110] At the same time, battery cells primarily rely on the movement of metal ions between the positive and negative electrodes to function. Taking lithium-ion batteries as an example, the positive electrode current collector can be made of aluminum, the positive electrode active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc., the negative electrode current collector can be made of copper, and the negative electrode active material layer can be made of carbon or silicon. During charging and discharging, Li+ ions are repeatedly inserted and extracted between the two electrodes. During charging, Li+ ions are extracted from the positive electrode and inserted into the negative electrode through the electrolyte, leaving the negative electrode in a lithium-rich state, and vice versa during discharging.

[0111] In recent years, new energy vehicles have made great strides, and in the field of electric vehicles, batteries play an irreplaceable and important role as the power source for electric vehicles. As a core component of new energy vehicles, batteries must meet high requirements in terms of both energy density and reliability.

[0112] In manufacturing a battery cell in the related art, an active material layer is applied to a current collector and then cut to obtain electrode pieces consisting of a current collector coated with an active material layer (referred to as an active material coated portion) and a current collector not coated with an active material layer (referred to as a tab sheet). Next, positive and negative electrode pieces and a separator are sequentially stacked or wound to obtain an electrode assembly, and multiple tab sheets in the electrode assembly are stacked and installed to form a tab portion. A pole is installed in the battery cell casing, and the surface of the pole facing the active material coated portion is the pole inner end surface. When manufacturing the battery cell, the tab portion is usually welded directly to the pole inner end surface or indirectly to the pole inner end surface via an adapter sheet to ensure normal charging and discharging operations.

[0113] In the related art, a battery cell includes a casing and an electrode assembly, the casing including a casing body and a top cover, the casing having an accommodating cavity, the accommodating cavity having an opening, the electrode assembly being inserted into the accommodating cavity through the opening, the top cover covering the opening and welded to the casing body, and a pole mounted on the top cover, the electrode assembly having a conductive portion, the conductive portion including a first converging portion formed by converging a plurality of tab sheets, and a second converging portion formed by converging and connecting the first converging portion, the second converging portion being electrically connected directly or indirectly to the pole. In the assembly process for a battery cell with this structure, typically, the second converging portion is first welded directly or indirectly to the pole on the top cover, the electrode assembly is then inserted into the casing body, and the top cover is then welded to the casing body. The conductive part must first be directly or indirectly welded to the pole on the top cover and then inserted into the casing. Because the position and size of the pole on the top cover are differentiated, the overall length of the conductive part is usually long to accommodate the pole on the top cover and ensure ease of welding. However, the inventors discovered that if the conductive part is relatively long, reverse insertion is likely to occur due to the redundancy of the second convergence part, which will affect the reliability of the battery cell.

[0114] In view of these considerations, the inventors adjusted the relative positions of the converging positions of the multiple tab sheets in the conductive portion and the electrode post so that at least a portion of the orthogonal projection of the end portion of the electrode post along the first direction where the second converging portion is connected to the first converging portion is located within the outer contour range of the electrode post. This arrangement is advantageous, on the one hand, for shortening the length of the second converging portion in a direction perpendicular to the first direction, and at least a portion of the second converging portion can be located within the outer contour range of the electrode post after extending from the end portion, facilitating welding between the conductive portion and the electrode post. On the other hand, this arrangement is advantageous, on the other hand, for shortening the overall length of the conductive portion, which is advantageous not only for reducing the cost of the conductive portion but also for alleviating the problem of reverse insertion due to the redundancy of the conductive portion, thereby improving the reliability of the battery cell.

[0115] An embodiment of the present application provides an electric device using the battery cell of the present disclosure as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, an electric scooter, an electric car, a steamship, a spacecraft, etc. Among them, the electric toy may include a stationary or mobile electric toy, such as a game console, an electric car toy, an electric boat toy, and an electric plane toy, and the spacecraft may include an airplane, a rocket, a space shuttle, a spaceship, etc.

[0116] For convenience of explanation, in the following embodiments, the structures of the electric device 1000, the battery 100, and the battery cell 10 of the present application will be described in detail using a vehicle as an example of the electric device.

[0117] Referring to FIG. 1, FIG. 1 is a structural schematic diagram of an electric device 1000, which is a vehicle provided by some embodiments of the present application. The vehicle may be a fuel-powered vehicle, a gas-powered vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle, a range-extended vehicle, etc. A battery 100 is installed in the vehicle, and the battery 100 may be installed at the bottom, head, or tail of the vehicle. The battery 100 is used to supply power to the vehicle. For example, the battery 100 may function as an operating power source for the vehicle. The vehicle may further include a controller 200 and a motor 300. The controller 200 controls the battery 100 to supply power to the motor 300, for example, to meet the operating power needs during starting, navigation, and driving of the vehicle. In some embodiments of the present application, the battery 100 can be used not only as an operating power source for the vehicle but also as a driving power source for the vehicle, thereby providing driving power to the vehicle in place of or partially replacing fuel or natural gas.

[0118] Referring to FIG. 2, FIG. 2 is an exploded view of a structure in which battery cells 10 provided according to some embodiments of the present application are used in a battery 100. The battery 100 includes a case 20 and a plurality of battery cells 10 housed within the case 20. The case 20 is used to provide an assembly space for the battery cells 10, and the case 20 can have various structures. In some embodiments, the case 20 can include a first case 201 and a second case 202, which cover each other and together define an assembly space for housing the battery cells 10. The second case 202 can have a hollow structure with one end open, or the first case 201 can have a plate-like structure, with the first case body 201 covering the open side of the second case 202 so that the first case 201 and the second case 202 jointly define the assembly space. Alternatively, the first case 201 and the second case 202 may both have a hollow structure with one side open (for example, as shown in FIG. 2), with the open side of the first case 201 being covered by the open side of the second case 202. Naturally, the case 20 formed by the first case 201 and the second case 202 may have various shapes, such as a cylindrical shape or a rectangular parallelepiped shape.

[0119] In the battery 100, the plurality of battery cells 10 can be connected in series, parallel, or series-parallel, and a series-parallel connection means that the plurality of battery cells 10 are connected in both series and parallel. The plurality of battery cells 10 can also be connected in direct series, parallel, or series-parallel, and the entire plurality of battery cells 10 is housed within a case 20. Alternatively, the battery 100 may be in a form in which the plurality of battery cells 10 are first connected in series, parallel, or series-parallel to form a battery module, and the plurality of battery modules are further connected in series, parallel, or series-parallel to form an integrated battery module and housed within a case 20. The battery 100 may further include other structures; for example, the battery 100 may further include a bus member for realizing electrical connection between the plurality of battery cells 10.

[0120] Referring to FIG. 3, FIG. 3 is a schematic diagram of a battery cell 10 provided according to some embodiments of the present application. The battery cell 10 has a rectangular parallelepiped shape. However, the battery cell 10 is not limited thereto, and in other embodiments of the present application, the battery cell 10 may have a cylindrical shape, a flat shape, or other shapes. Referring to FIG. 4 and FIG. 5, FIG. 4 is an orthographic view of a battery cell 10 provided according to some embodiments of the present application. FIG. 5 is a cross-sectional view taken along line AA in FIG. 4. In the embodiment of the present application, the battery cell 10 includes a casing assembly 1 and a battery core assembly 2, and the casing assembly 1 includes a casing 11 and a pole 12 installed in the casing 11.

[0121] The shape of the casing 11 can be 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 particularly limited. For example, if the battery cell 10 is a prismatic battery, the casing 11 will be prismatic, and if the battery cell 10 is a cylindrical battery, the casing 11 will be cylindrical. In the embodiments of the present application, all casings 11 will be described as prismatic. Electrode posts 12 are provided on the casing 11 and are used for electrical connection with the battery core assembly 2 to ensure normal charging and discharging of the battery cell 10. Generally, there are at least two electrode posts 12, specifically at least one positive electrode post and at least one negative electrode post. For example, if there are two electrode posts 12, one is a positive electrode post and the other is a negative electrode post, which are electrically connected to the positive and negative output positions of the battery core assembly 2, respectively. For example, if there are four electrode poles 12, two may be positive electrode poles and the remaining two may be negative electrode poles, and in this case, the two positive electrode poles are both electrically connected to the positive electrode output positions of the battery core assembly 2, and the two negative electrode poles are both electrically connected to the negative electrode output positions of the battery core assembly 2. Of course, in other embodiments of the present application, the casing assembly 1 may further include only one electrode pole 12, and the electrode pole 12 may include two parts that are insulated and connected, and serve as a positive electrode pole and a negative electrode pole, respectively.

[0122] 4 and 5 again, in the embodiment of the present application, the battery core assembly 2 includes an active material-coated portion 21 and a conductive portion 22, and the conductive portion 22 is electrically connected to the active material-coated portion 21 and the electrode post 12. Here, the active material-coated portion 21 is housed within the casing 11, and is a portion of the battery core assembly 2 to which an active material is applied, and can assist in the insertion and desorption of metal ions during the charge and discharge process of the battery cell 10. The conductive portion 22 is a metal structure that electrically connects the active material-coated portion 21 and the electrode post 12, and is not coated with an active material. The electrode post 12 is electrically connected to the active material-coated portion 21 via the conductive portion 22 so that the charge and discharge operation of the battery cell 10 is possible.

[0123] For illustrative purposes, in the present embodiment, the active material-coated portion 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211, and the conductive portion 22 includes a tab portion 221 electrically connected to the current collector 211. Here, the active material-coated portion 21 is divided into a positive electrode active material-coated portion and a negative electrode active material-coated portion, the positive electrode active material-coated portion including a portion where a positive electrode active material layer is coated on a positive electrode current collector, and the negative electrode active material-coated portion including a portion where a negative electrode active material layer is coated on a negative electrode current collector. The conductive portion 22 is divided into a positive electrode conductive portion and a negative electrode conductive portion, the positive electrode conductive portion including a positive electrode tab electrically connected to the positive electrode current collector and the positive electrode pole, and the negative electrode conductive portion including a negative electrode tab electrically connected to the negative electrode current collector and the negative electrode pole.

[0124] 3 to 5, the tab portion 221 includes a plurality of tab sheets 2211, which are electrically connected to the current collector 211 but are not coated with active material. The tab sheets 2211 can be formed by directly stamping the current collector 211. Ends of the plurality of tab sheets 2211 adjacent to the active material coated portion 21 converge together (i.e., converge toward each other) to form a first converging portion 2212, and ends of the plurality of tab sheets 2211 away from the active material coated portion 21 converge and connect to form a second converging portion 2213, with the first converging portion 2212 connected to the second converging portion 2213 and the active material coated portion 21. In some alternative examples, the active material coated portion 21 and the tab sheets 2211 can be an integral part, such as an aluminum foil integrally molded with the positive electrode piece, or a copper foil integrally molded with the negative electrode piece.

[0125] In the above technical solution, the multiple tab sheets 2211 simply converge (i.e., converge toward each other) but are not connected when forming the first converging portion 2212, but when forming the second converging portion 2213, the multiple tab sheets 2211 not only converge but also connect to form an integrated structure. For example, the multiple tab sheets 2211 can be connected to an integrated plate-like structure by welding (e.g., ultrasonic welding) to form the second converging portion 2213, or the multiple tab sheets 2211 can be gathered and connected by a method such as bonding with a conductive adhesive to form the second converging portion 2213, and the description thereof will be omitted here.

[0126] For illustrative purposes, in the present embodiment, the tab sheet 2211 is divided into a positive electrode tab sheet 2211 and a negative electrode tab sheet 2211. The positive electrode tab sheets 2211 that need to converge are stacked and ultrasonically tack-welded to form a positive electrode second convergence portion 2213, thereby reducing the interlayer gap and forming a plate-like structure with a certain rigidity from the plurality of puffed positive electrode tab sheets 2211. Similarly, the negative electrode tab sheets 2211 that need to converge are stacked and ultrasonically tack-welded to form a negative electrode second convergence portion 2213, thereby reducing the interlayer gap and forming a plate-like structure with a certain rigidity from the plurality of puffed negative electrode tab sheets 2211.

[0127] In the above technical solution, “the plurality of tab sheets 2211 converge at one end close to the active material application portion 21 to form a first convergent portion 2212, and the plurality of tab sheets 2211 converge at one end away from the active material application portion 21 while connecting to form a second convergent portion 2213” means that the first convergent portion 2212 and the second convergent portion 2213 are arranged in this order along the extension direction of the tab sheet 2211 in a direction away from the active material application portion 21, and the specific positions of the first convergent portion 2212 and the second convergent portion 2213 are not limited, i.e., there is no requirement for the first convergent portion 2212 to be close to the active material application portion 21 or the second convergent portion 2213 to be far from the active material application portion 21.

[0128] In the present embodiment, the direction in which the tab sheet 2211 extends from the active material-coated portion 21 is the first direction Z. The first direction Z is mainly the direction in which the tab sheet 2211 extends relative to the current collector 211 before convergence, and in this case, the tab sheet 2211 and the corresponding current collector 211 are located in the same plane. That is, the first direction Z is not the direction in which the tab sheet 2211 extends after convergence, but it mainly characterizes the direction in which the tab sheet 2211 is arranged relative to the active material-coated portion 21 before convergence, and specifically, this direction is the axial direction of the electrode post 12. 3 to 5, when the electrode post 12 is provided on the top of the casing 11, the tab sheet 2211 extends above the active material-coated portion 21, and whether the tab sheet 2211 extends vertically upward or obliquely upward, the vertically upward direction is the first direction Z, and in this case, the first direction Z is also the height direction of the battery cell 10, the length direction of the battery cell 10 may be the second direction X, and the thickness direction of the battery cell 10 may be the third direction Y, and the first direction Z, the second direction X, and the third direction Y are perpendicular to each other two by two. This is not limiting, and for example, the electrode post 12 may also be provided on the bottom of the casing 11, and the tab sheet 2211 may extend downward from the active material-coated portion 21, in which case the vertically downward direction may be the first direction, and description thereof will be omitted here.

[0129] 4 to 6, Fig. 6 is a schematic orthogonal projection diagram of portion F in Fig. 4. In the present embodiment, the orthogonal projection P1 of the end 2214 where the second convergent portion 2213 is connected to the first convergent portion 2212 on the polar column 12 along the first direction Z is at least partially located within the outer contour range S of the polar column 12. In Fig. 6(a), the outer contour range S of the polar column 12 is indicated by a solid line, and the shaded portion in Fig. 6(a) represents the orthogonal projection P1 of the end 2214 along the first direction Z on the polar column 12. Here, the "end 2214" of the end 2214 where the second convergent portion 2213 is connected to the first convergent portion 2212 refers to the position where the second convergent portion 2213 is connected to the first convergent portion 2212, i.e., the starting position of the convergent connection of the tab sheet 2211, and can be understood to belong to a part of the second convergent portion 2213.

[0130] In other words, when orthogonally projected onto a projection plane perpendicular to the first direction Z, at least a part of the orthogonal projection P1 of the end 2214 on the projection plane is located within the range surrounded by the orthogonal projection profile of the polar pillar 12 on the projection plane. Here, the orthogonal projection of the polar pillar 12 on the projection plane may be a completely filled solid figure or a partially filled openwork figure. For example, in the example shown in Figure 5, when the polar pillar 12 has a first through-hole 12130 penetrating through it, the orthogonal projection of the polar pillar 12 on the projection plane is formed into a filled figure of the openwork part of the first through-hole 12130. In this case, even if at least a part of the orthogonal projection P1 of the end 2214 on the polar pillar 12 along the first direction Z is located at the openwork location, it belongs to the situation where it is located within the outer contour range S of the polar pillar 12. Referring again to FIG. 7, FIG. 7 is a schematic local cross-sectional view of a battery cell provided by some embodiments of the present application, in which the pole 12 can also be configured as a solid shape without a through-hole. In this case, the orthogonal projection of the pole 12 on the projection plane may be a completely filled solid figure, and the description thereof will be omitted here.

[0131] In the above technical solution, the ends of the plurality of tab sheets 2211 that are away from the active material-coated portion 21 are converged and connected to form a second convergent portion 2213. The end of the second convergent portion 2213 connected to the first convergent portion 2212 is at least partially orthogonally projected onto the pole in the first direction Z within the outer contour range S of the pole 12. This advantageously shortens the distance from the end 2214 of the conductive portion 22 to the pole 12 in the direction perpendicular to the first direction Z, so as to shorten the distance between the second convergent portion 2213 and the pole 12. After the second convergent portion 2213 extends from the end 2214, the length of the second convergent portion 2213 in the direction perpendicular to the first direction Z is advantageously shortened so that at least a portion of the second convergent portion 2213 is within the outer contour range of the pole 12, thereby facilitating welding between the conductive portion 22 and the pole 12. On the other hand, such an arrangement is advantageous in that it shortens the overall length of the conductive portion 22, which not only reduces the cost of the conductive portion 22 but also alleviates the problem of reverse insertion due to redundancy of the conductive portion 22, thereby improving the reliability of the battery cell 10. In addition, such an arrangement further concentrates the space occupied by the conductive portion 22 and the electrode post 12 in the direction perpendicular to the first direction Z, thereby reducing the overall space occupied by both the conductive portion 22 and the electrode post 12, freeing up the remaining space of the battery cell 10 in the direction perpendicular to the first direction Z, allowing other structures to be laid out, such as an insulating structure to further improve the reliability of the battery cell 10, or allowing a larger electrolyte to be accommodated to ensure the cycle life of the battery cell 10.

[0132] 5 and 6 again, in some embodiments of the present application, the orthogonal projections P1 of the end 2214 of the second converging portion 2213 connected to the first converging portion 2212 on the polar rod 12 along the first direction Z are all located within the outer contour range S of the polar rod 12. Since the tab sheet 2211 has an approximately sheet shape after converging, the orthogonal projection P1 of the end 2214 of the second converging portion 2213 connected to the first converging portion 2212 on the projection plane may be a line pattern or an elongated figure, and it can be understood that all of the line pattern or elongated figure is located within the range surrounded by the orthogonal projection profile of the polar rod 12 on the projection plane. By installing the conductive portion 22 in this manner, the distance from the end 2214 of the conductive portion 22 to the pole 12 can be more sufficiently shortened in the direction perpendicular to the first direction Z, thereby more effectively shortening the length of the conductive portion 22, further reducing the redundancy and cost of the conductive portion 22, and effectively improving the problem of reverse insertion, so as to further improve the reliability of the battery cell 10. Furthermore, the space occupied by the conductive portion 22 in the casing 11 in the direction perpendicular to the first direction Z can be reduced.

[0133] 5 and 6 again, in some embodiments of the present application, the orthogonal projections P2 of the second convergent portion 2213 on the polar pillar 12 along the first direction Z are all located within the outer contour range S of the polar pillar 12. In FIG. 6(b), the outer contour range S of the polar pillar 12 is indicated by a solid line, and the shaded area in FIG. 6(b) represents the orthogonal projection P2 of the second convergent portion 2213 on the polar pillar 12 along the first direction Z. In the above technical solution, when orthogonal projection is performed on a projection plane perpendicular to the first direction Z, the orthogonal projections of the second convergent portion 2213 on the projection plane are all located within the range surrounded by the orthogonal projection profile of the polar pillar 12 on the projection plane. By installing the conductive portion 22 in this manner, the distance from the second converging portion 2213 to the pole 12 can be more sufficiently shortened in the direction perpendicular to the first direction Z, thereby more effectively shortening the length of the conductive portion 22, further reducing the redundancy and cost of the conductive portion 22, further improving the reliability of the battery cell 10, and further reducing the space occupied by the conductive portion 22 in the casing 11 in the direction perpendicular to the first direction Z.

[0134] FIG. 8 is a schematic cross-sectional view of a battery core assembly 2 provided according to some embodiments of the present application. See FIGS. 5 and 8. In some embodiments, the second converging portion 2213 may include a plurality of connecting steps 22130, the plurality of connecting steps 22130 being connected in sequence, and any two adjacent connecting steps 22130 being arranged at an angle. For example, the second converging portion 2213 includes a first connecting step 22131 and a second connecting step 22132 connected in sequence, the first connecting step 22131 being connected between the second connecting step 22132 and the first converging portion 2212, and the first connecting step 22131 and the second connecting step 22132 being arranged at an angle. For example, the angle δ may be 90°, may be greater than 90°, or may be less than 90°. If the orthogonal projections P2 of the second converging portion 2213 on the pole pillar 12 along the first direction Z are all located within the outer contour range S of the pole pillar 12, the orthogonal projections P2 of each connecting stage 22130 on the pole pillar 12 along the first direction Z are all located within the outer contour range S of the pole pillar 12.

[0135] This allows the second converging portion 2213 to be adapted to electrode posts 12 of different structures by setting the number and angle of the connecting sections 22130, which is advantageous in realizing a direct connection between the second converging portion 2213 and the electrode post 12, thereby simplifying the structure, reducing costs, and improving production efficiency. However, this is not limited thereto, and when the second converging portion 2213 includes multiple connecting sections 22130, the second converging portion 2213 may be indirectly connected to the electrode post 12 via another conductive member, but this will not be described here.

[0136] 5 and 6, in some embodiments, the orthogonal projection P3 of the first converging portion 2212 on the polar cylinder 12 along the first direction Z is at least partially located within the outer contour range S of the polar cylinder 12. In Fig. 6(c), the outer contour range S of the polar cylinder 12 is shown by a solid line, and the shaded area in Fig. 6(c) represents the orthogonal projection P3 of the first converging portion 2212 on the polar cylinder 12 along the first direction Z. In the above technical solution, when orthogonally projected onto a projection plane perpendicular to the first direction Z, at least a portion of the orthogonal projection of the first converging portion 2212 on the projection plane is located within the range surrounded by the orthogonal projection profile of the pole 12 on the projection plane, thereby shortening the distance from the first converging portion 2212 to the pole 12 in the direction perpendicular to the first direction Z, further shortening the length of the conductive portion 22, further reducing the redundancy and cost of the conductive portion 22, further improving the reliability of the battery cell 10, and further reducing the occupation of the space within the casing 11 by the conductive portion 22 in the direction perpendicular to the first direction Z.

[0137] For example, referring to Figures 5 and 6, the orthogonal projections P3 of the first converging portion 2212 on the pole 12 along the first direction Z can all be located within the outer contour range S of the pole 12, thereby further shortening the length of the conductive portion 22 in a direction perpendicular to the first direction Z, further reducing the redundancy and cost of the conductive portion 22, and further reducing the occupation of space within the casing 11 by the conductive portion 22 in a direction perpendicular to the first direction Z.

[0138] FIG. 9 illustrates a diagram of a plurality of tab convergence designs for a battery core assembly 2 according to some embodiments of the present disclosure. Referring to FIG. 9 , in some embodiments, when the battery core assembly 2 includes two electrode assemblies 2a, the tab sheets 2211 of the two electrode assemblies 2a may converge together, and the convergence position may be at a central position between the two electrode assemblies 2a, forming a symmetrically converged shape (e.g., as shown in FIGS. 8 and 9(a)). In some other embodiments, when the tab sheets 2211 of the two electrode assemblies 2a converge together, the convergence position may be adjacent to one electrode assembly 2a, forming an asymmetrically converged shape (e.g., as shown in FIGS. 9(b) and 9(c)). Furthermore, the electrode assemblies 2a may have a full tab extension shape (e.g., as shown in FIG. 9(a)) or a half tab extension shape (e.g., as shown in FIGS. 8, 9(b), and 9(c)). Of course, the tab sheets 2211 of the same polarity of the two electrode assemblies 2a do not necessarily have to converge together. For example, the tab sheets 2211 of each electrode assembly 2a are individually converged for the positive and negative electrodes, i.e., the positive electrode tabs of one electrode assembly 2a are individually converged, and the positive electrode tabs of another electrode assembly 2a are also individually converged, but this will not be described here.

[0139] Thus, depending on the specific position of the electrode post 12, the converging form of the tabbed sheet 2211 can be correspondingly designed to meet the requirements of the relative positional relationship between the tabbed sheet 2211 and the electrode post 12. For example, when the electrode post 12 is centrally installed with respect to the casing 11, the tabbed sheet 2211 may be installed in a substantially symmetrically converging form. For example, when the electrode post 12 is eccentrically installed with respect to the casing 11, the tabbed sheet 2211 may be installed in a substantially asymmetrically converging form. For example, when the electrode assembly 2a is formed in a fully tab-extending form, the orthogonal projection of the first converging portion 2212 on the electrode post 12 along the first direction Z may be located locally within the outer contour range S of the electrode post 12. For example, when the electrode assembly 2a is formed in a half tab-extending form, the orthogonal projection of the first converging portion 2212 on the electrode post 12 along the first direction Z may be located locally or entirely within the outer contour range S of the electrode post 12.

[0140] Specifically, one pole 12 may be connected to only one conductive portion 22 (for example, as shown in FIGS. 5 and 7), or one pole 12 may be connected to multiple conductive portions 222 simultaneously (for example, as shown in FIG. 10, which is an orthogonal projection view of a battery cell 10 provided according to some embodiments of the present application). In some optional embodiments of the present application, referring to FIG. 10, when one pole 12 is connected to multiple conductive portions 222 simultaneously, at least a portion of the orthogonal projection P1 of the end 2214 of each conductive portion 22, where the second converging portion 2213 is connected to the first converging portion 2212, on the pole 12 along the first direction Z, is located within the outer contour range S of the pole 12. In the above technical solution, by locating at least a portion of the orthogonal projection P1 along the first direction Z of the end 2214 of each conductive part 22 within the range surrounded by the orthogonal projection profile along the first direction Z of the pole 12 connected to the conductive part 22, the distance from the end 2214 of each conductive part 22 to the pole 12 can be more fully and effectively shortened, the length of the conductive part 22 can be further shortened, the reliability of the battery cell 10 can be further improved, and the occupation of the space within the casing 11 in the direction perpendicular to the first direction Z of the conductive part 22 can be further reduced.

[0141] 5 and 6, in some embodiments of the present application, the end 2214 at which the second converging portion 2213 is connected to the first converging portion 2212 may be orthogonally projected on the polar pole 12 along the first direction Z so as to be centered relative to the polar pole 12, i.e., when orthogonally projected onto a projection plane perpendicular to the first direction Z, the orthogonal projection of the end 2214 on the projection plane and the center line L of the orthogonal projection of the polar pole 12 on the projection plane have an overlapping region, for example, the line pattern formed by the projection of the end 2214 can be positioned so as to overlap with the center line of the length of the projection of the polar pole 12 (i.e., the center line extending along the length direction).

[0142] 7 again, in some other embodiments of the present application, an orthogonal projection P1 of the end 2214, where the second converging portion 2213 is connected to the first converging portion 2212, on the pole 12 along the first direction Z is disposed eccentrically with respect to the pole 12. By disposing the orthogonal projection P1 of the end 2214 on the pole 12 along the first direction Z eccentrically with respect to the pole 12, i.e., by orthogonally projecting the end 2214 onto a projection plane perpendicular to the first direction Z, the orthogonal projection P1 of the end 2214 on the projection plane is misaligned with the center line L of the orthogonal projection of the pole 12 on the projection plane. This increases the area of ​​the portion of the pole 12 that is electrically connected to the conductive portion 22, thereby improving the area where the pole 12 is electrically connected to the conductive portion 22 and, consequently, the current passing capacity of the electrical connection is improved, which is advantageous for improving charging efficiency. Furthermore, when one pole 12 is connected to multiple conductive parts 22 simultaneously, if the orthogonal projection of the end 2214 on the pole 12 along the first direction Z is set eccentrically relative to the pole 12, this is advantageous in making full use of the space of the pole 12 and reducing the difficulty of connecting each conductive part 22 to the pole 12.

[0143] For example, if the tab sheet 2211 has a roughly sheet shape after converging, and the orthogonal projection of the end 2214 where the second converging portion 2213 is connected to the first converging portion 2212 on the projection plane is a line pattern, the projection of the pole 12 on the projection plane may be an elongated shape whose length is greater than its width, such as a rectangle, an ellipse, or a racetrack. The line pattern formed by the projection of the end 2214 can be arranged parallel to the center line of the projection length of the pole 12 (i.e., the center line extending along the length direction), which can simply and effectively achieve the orthogonal projection of the end 2214 on the pole 12 along the first direction Z to be arranged eccentrically with respect to the pole 12, and can also fully utilize the space of the pole 12, which is advantageous for the electrical connection with the conductive part 22.

[0144] In the embodiments of the present application, the second converging portion 2213 and the electrode post 12 may be electrically connected directly or indirectly. For example, referring to Fig. 10, when the second converging portion 2213 is directly electrically connected to the electrode post 12, for example, when the second converging portion 2213 is welded (e.g., laser welded) to the electrode post 12, the structure of the battery core assembly 2 can be simplified, the number of components can be reduced, the assembly process can be simplified, and assembly efficiency can be improved. Meanwhile, the method and position of the direct electrical connection between the second converging portion 2213 and the electrode post 12 are not limited.

[0145] 11 is a schematic cross-sectional view of a battery cell 10 according to some embodiments of the present application. Referring to FIG. 11 , in some embodiments, when the second converging portion 2213 is indirectly electrically connected to the electrode post 12, the conductive portion 22 may further include an adapter sheet 222. The adapter sheet 222 is used to connect the second converging portion 2213 and the electrode post 12. That is, the adapter sheet 222 is electrically connected to the second converging portion 2213, and the adapter sheet 222 is electrically connected to the electrode post 12. The active material coated portion 21 can be electrically connected to the electrode post 12 via the first converging portion 2212, the second converging portion 2213, and the adapter sheet 222, in that order. The electrical connection between the conductive portion 22 and the electrode post 12 is located on the adapter sheet 222. For example, the electrical connection can be achieved by welding (e.g., laser welding) the adapter sheet 222 to the electrode post 12. Furthermore, the adapter sheet 222 and the tab sheet 2211 are two separate members that are connected by welding (e.g., ultrasonic welding) or other methods. By using the adapter sheet 222 to achieve an indirect electrical connection between the second converging portion 2213 and the electrode post 12, the adapter sheet 222 can be welded to the electrode post 12 at a location that avoids the second converging portion 2213. This strengthens the weld between the adapter sheet 222 and the electrode post 12, reduces the risk of weld cracking, and further improves the reliability and stability of the battery cell 10. At the same time, electrically connecting the electrode post 12 and the tab sheet 2211 via the adapter sheet 222 also simplifies the structure of the tab sheet 2211.

[0146] Referring again to FIG. 11 , in some embodiments, when the conductive portion 22 includes an adapter sheet 222, at least a portion of the orthogonal projection P4 on the pole pillar 12 along the first direction Z of the adapter sheet 222 may be located within the outer contour range S of the pole pillar 12.

[0147] In the above technical solution, by orthogonally projecting onto a projection plane perpendicular to the first direction Z, at least a portion of the orthogonal projection P4 of the adapter sheet 222 within the projection plane is positioned within the range surrounded by the orthogonal projection profile of the pole 12 within the projection plane, thereby shortening the length of the adapter sheet 222 and reducing the cost and redundancy of the adapter sheet 222, and thus more fully reducing the redundancy and cost of the conductive part 22, which is advantageous for further improving the reliability of the battery cell 10 and reducing the space occupied by the adapter sheet 222 within the casing 11.

[0148] FIG. 12 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application. Referring to FIG. 12, in some embodiments of the present application, at least one electrode post 12 in a casing 11 has a receiving portion 121 formed therein. That is, the receiving portion 121 may be formed in all or some of the electrode posts 12 in the casing 11. The electrode post 12 having the receiving portion 121 formed therein may be a positive electrode post or a negative electrode post, and the present disclosure is not limited thereto. The receiving portion 121 is a virtual structure having a receiving space, and may be a groove-like structure, a hole-like structure, or a composite structure of a groove-like structure and a hole-like structure.

[0149] 12 , at least a portion of the conductive portion 22 is accommodated in the corresponding accommodating portion 121. Here, "at least a portion" means that the conductive portion 22 is completely accommodated in the accommodating portion 121, or that only a portion of the conductive portion 22 is accommodated in the accommodating portion 121. Because the accommodating portion 121 is provided in the pole 12, the hollow structure of the accommodating portion 121 can reduce the weight of the pole 12 to some extent, thereby improving the weight-energy density of the battery cell 10 and the battery 100.

[0150] Furthermore, by accommodating some or all of the conductive portion 22 within the accommodating portion 121, the portion of the conductive portion 22 located within the accommodating portion 121 can occupy space within the electrode post 12, thereby reducing the space occupied by the conductive portion 22 within the casing 11. If the dimensions of the casing 11 are fixed, some space can be saved within the casing 11 to accommodate a larger-sized active material-coated portion 21, thereby improving the volumetric energy density of the battery cell 10. For example, if the conductive portion 22 is extended from the side of the active material-coated portion 21 closest to the electrode post 12, the space occupied by the conductive portion 22 between the active material-coated portion 21 and the electrode post 12 can be reduced, thereby increasing the dimension of the active material-coated portion 21 in the direction in which the conductive portion 22 is extended and reducing the distance between the active material-coated portion 21 and the electrode post 12, thereby improving the energy density of the battery cell 10.

[0151] 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 more battery cells 10 to be accommodated in a battery 100 of the same volume, thereby further improving 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, space within the pole 12 is occupied, thereby reducing at least to some extent the redundancy of the conductive portion 22 within the casing 11, reducing the probability of a short circuit between the conductive portion 22 and the active material coated portion 21, reducing the probability of a short circuit in the battery cell 10, and improving the operational reliability and stability of the battery cell 10 and the battery 100.

[0152] Furthermore, accommodating at least a portion of the conductive portion 22 within the accommodating portion 121 is advantageous in further stabilizing and positioning the conductive portion 22, and improving the stability of the conductive portion 22 facilitates welding the conductive portion 22 to the electrode post 12, improving assembly efficiency. Furthermore, when the electrode post 12 having the accommodating portion 121 formed therein is positioned at the bottom of the casing 11 in the direction of gravity, the accommodating portion 121 can accommodate the electrolyte, improving the cycle life of the battery cell 10.

[0153] Furthermore, since at least one electrode post 12 is provided with a accommodating section 121, when the accommodating section 121 is located on the side of the electrode post 12 that is away from the active material coated section 21, welding of the portion of the conductive section 22 located within the accommodating section 121 to the electrode post 12 can be achieved from outside the casing 11 via the accommodating section 121; when the accommodating section 121 is located on the side facing the active material coated section 21 of the electrode post 12, the thickness of the local portion of the electrode post 12 that corresponds to the accommodating section 121 is reduced, so that welding of the portion of the conductive section 22 accommodated within the accommodating section 121 to the electrode post 12 can be achieved from outside the casing 11 at the thinned portion; therefore, even if the length of the portion of the conductive section 22 located within the casing 11 is relatively short, welding of the conductive section 22 to the electrode post 12 can be performed from outside the casing 11, which facilitates welding of the conductive section 22 to the electrode post 12 and improves the reliability of welding between the conductive section 22 and the electrode post 12.

[0154] 13 is a schematic cross-sectional view of a battery cell according to some embodiments of the present disclosure, and FIG. 14 is a schematic cross-sectional view of a battery cell according to some embodiments of the present disclosure. Referring to FIGS. 13 and 14 , in some embodiments of the present disclosure, whether the second converging portion 2213 is directly or indirectly electrically connected to the electrode post 12, at least a portion of the second converging portion 2213 can be accommodated in the accommodating portion 121. In the above technical solution, accommodating at least a portion of the second converging portion 2213 in the accommodating portion 121 can more fully utilize the space within the electrode post 12, further reduce the space occupied by the conductive portion 22 within the casing 11, and improve the volumetric energy density of the battery cell 10.

[0155] 14 again, in some embodiments, when the conductive part 22 includes an adapter sheet 222 for connecting the second converging part 2213 and the electrode post 12, regardless of whether at least a portion of the second converging part 2213 is accommodated in the accommodating part 121, at least a portion of the adapter sheet 222 can be accommodated in the accommodating part 121. In the above technical solution, by accommodating at least a portion of the adapter sheet 222 in the accommodating part 121, the space within the electrode post 12 can be more fully utilized, the space occupied by the conductive part 22 in the casing 11 can be further reduced, and the volumetric energy density of the battery cell 10 can be improved.

[0156] 13 and 14 , in some embodiments, at least a portion of the first converging portion 2212 may be accommodated in the accommodating portion 121. In the above technical solution, by accommodating at least a portion of the first converging portion 2212 in the accommodating portion 121, the space within the pole 12 can be further utilized, the space occupied by the conductive portion 22 within the casing 11 can be more effectively reduced, and the volumetric energy density of the battery cell 10 can be improved.

[0157] Of course, there may be at least one electrode post 12 that does not have a receiving portion 121. For example, referring to FIG. 7 , when an electrode post 12 that does not have a receiving portion 121 is installed in the casing 11, a clearance groove 18 can be provided between the electrode post 12 and the casing 11 as needed so that at least a portion of the conductive portion 22 is received in the clearance groove 18. This reduces the space occupied by the conductive portion 22 in the casing 11 to some extent, which is advantageous for improving energy density and alleviating short-circuit problems caused by redundancy of the conductive portion 22. For simplicity of explanation, this specification will only describe an example in which all electrode posts 12 have a receiving portion 121.

[0158] In the embodiments of the present application, the accommodating portion 121 may be located on the side facing the active material applied portion 21 of the electrode post 12, or on the side away from the active material applied portion 21 of the electrode post 12. For example, referring to FIGS. 12 to 14 , when the accommodating portion 121 is located on the side facing the active material applied portion 21 of the electrode post 12, the accommodating portion 121 has a first accommodating groove 12110, the surface of the electrode post 12 facing the active material applied portion 21 is the electrode post inner end face 122, the groove opening of the first accommodating groove 12110 is formed in the electrode post inner end face 122, and at least a part of the conductive portion 22 is accommodated in the first accommodating groove 12110.

[0159] For example, the first accommodating groove 12110 is a groove body, and the groove body has a groove-like structure with a certain depth. For example, when the electrode post 12 is installed on the upper end wall of the casing 11 and the electrode post inner end surface 122 is the lower surface of the electrode post 12, the first accommodating groove 12110 is formed as an accommodating groove with a groove opening downward and groove walls recessed upward. For example, when the electrode post 12 is installed on the lower end wall of the casing 11 and the electrode post inner end surface 122 is the upper surface of the electrode post 12, the first accommodating groove 12110 is formed as an accommodating groove with a groove opening upward and groove walls recessed downward.

[0160] In the above technical solution, on the one hand, the weight of the electrode post 12 can be reduced to a certain extent by forming the first accommodating groove 12110 in the electrode post 12, so as to improve the weight energy density of the battery cell 10 and the battery 100. On the other hand, the groove opening of the first accommodating groove 12110 is formed in the electrode post inner end surface 122, which is the surface of the electrode post 12 that is close to the active material coated portion 21. This allows the first accommodating groove 12110 to open toward the active material coated portion 21, which in turn makes it easier for the conductive portion 22 to extend into the first accommodating groove 12110, improving assembly efficiency. Furthermore, the first accommodating groove 12110 of this type is easy to process, improving manufacturing efficiency.

[0161] Furthermore, the first accommodating groove 12110 can be easily processed to have a larger volume, thereby being able to accommodate more conductive parts 22. At the same time, because the first accommodating groove 12110 opens toward the active material application part 21, the first accommodating groove 12110 can be used as a buffering and temporary storage structure for the electrolyte. The casing 11 can accommodate more electrolyte. Since the electrolyte is consumed during the charging and discharging process of the battery cell 10, an increased amount of electrolyte can extend the service life of the battery cell 10. Furthermore, because the first accommodating groove 12110 opens toward the active material application part 21, the first accommodating groove 12110 can also be used as a buffering structure for gas generated inside the battery core assembly 2, which can reduce the expansion of the battery cell 10 and improve the reliability and stability of the battery cell 10.

[0162] In addition, the first accommodating groove 12110 is located inside the pole 12, making it difficult for external foreign objects and impurities to enter the first accommodating groove 12110, thereby reducing the impact of external foreign objects and impurities on the battery core assembly 2, improving the stability and reliability of the operation of the battery core assembly 2, and ultimately improving the stability and reliability of the battery cell 10 and the battery 100.

[0163] 12 again, in the embodiment of the present application, the method of connecting the terminal post 12 and the casing 11 is not limited, and may be, for example, welding or riveting. For example, when the two are fitted together by riveting, the casing 11 has a mounting hole 113, and the terminal post 12 is attached to the mounting hole 113 by riveting. Of course, when the two are fitted together by welding or another method, it can be understood that the casing 11 may have a mounting hole 113 so that the terminal post 12 can be easily attached to the casing 11 through the mounting hole 113, and this is not limited here. At the same time, the first accommodating groove 12110 may be installed corresponding to the position of the mounting hole 113, or in a projection plane perpendicular to the first direction Z, the orthogonal projection of the first accommodating groove 12110 is located within the orthogonal projection range of the mounting hole 113, so that the first accommodating groove 12110 can have a relatively large depth so as to accommodate more conductive parts 22, and thus the space occupied by the conductive parts 22 in the casing 11 can be more significantly reduced.

[0164] Specifically, when a mounting hole 113 is opened in the casing 11 and the pole 12 is mounted in the mounting hole 113, the depth H1 of the first accommodating groove 12110 along the first direction Z is greater than or equal to the minimum distance H2 from the pole inner end face 122 to the mounting hole 113.

[0165] It should be noted that the specific shape of the first housing groove 12110 is not particularly limited and may be a regular or irregular shape, such as a cylindrical groove having a rectangular, elliptical, or racetrack-shaped cross section (a structure formed by two arcs and two straight lines surrounding each other), a trapezoidal groove having a rectangular cross section with gradually varying cross-sectional dimensions, a hemispherical groove having a circular cross section with gradually varying cross-sectional dimensions, or a semi-elliptical groove having an elliptical cross section with gradually varying cross-sectional dimensions. Therefore, the depth H1 of the first housing groove 12110 refers to the maximum depth of the first housing groove 12110 along the first direction Z.

[0166] In the first direction Z, the depth H1 of the first accommodating groove 12110 is equal to or greater than the minimum distance H2 from the pole inner end surface 122 to the mounting hole 113, thereby fully utilizing the volume of the pole 12. As a result, the first accommodating groove 12110 has a relatively large depth, which is advantageous for accommodating more conductive parts 22 and thus significantly reducing the space occupied by the conductive parts 22 within the casing 11, further improving the energy density of the battery cell 10 and reducing the redundancy of the conductive parts 22 within the casing 11. At the same time, the relatively large depth of the first accommodating groove 12110 also allows it to accommodate gas generated by the battery core assembly 2, ensuring the reliability and stability of the battery cell 10, and allowing it to accommodate more electrolyte, thereby ensuring the service life of the battery cell 10.

[0167] It should be further explained 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 (referred to as the first volume V1) for receiving the conductive portion 22 is 298 mm 3 or more, so that the first accommodating groove 12110 can have a relatively sufficient space to accommodate the conductive portion 22 and facilitate welding of the conductive portion 22 to the terminal post 12. On the other hand, if the first volume V1 of the first accommodating groove 12110 is 298 mm 3 If it is less than this, the capacity of the first accommodating groove 12110 to accommodate the conductive part 22 becomes relatively weak, and the difficulty of welding the conductive part 22 and the terminal post 12 becomes high.

[0168] Furthermore, it should be explained that the first volume V1 of the first accommodating groove 12110 is the difference between the total volume V2 of the first accommodating groove 12110 and the volume (denoted as second volume V3) required for the first accommodating groove 12110 to accommodate components other than the conductive portion 22, i.e., V1 = V2 - V3. As can be understood, if the first accommodating groove 12110 does not need to accommodate components other than the conductive portion 22, the second volume V3 is 0 mm 3 For example, the first volume V1 of the first receiving groove 12110 can be 300 mm 3 ~1500mm 3For example, 300 mm 3 , 400mm 3 , 500mm 3 , 600mm 3 , 700mm 3 , 800mm 3 , 1000mm 3 , 1200mm 3 , 1400mm 3 , 1500mm 3 etc.

[0169] 12 and 13 , in order to ensure the stability and reliability of the electrical connection between the active material coating portion 21 and the electrode post 12, in this embodiment, the electrical connection position between the conductive portion 22 and the electrode post 12 may be located on the groove wall of the first receiving groove 12110. For example, the electrical connection between the conductive portion 22 and the electrode post 12 may be formed by welding, and the electrical connection position is the welding position between the conductive portion 22 and the electrode post 12. At the same time, the welding method between the conductive portion 22 and the electrode post 12 is not limited and may be, for example, laser welding. Depending on factors such as the position, angle, or structure of the welding portion, vertical welding, inclined welding, lap welding, edge welding, etc. may be selected. In other embodiments of the present application, the electrical connection between the conductive portion 22 and the electrode post 12 may be achieved by other methods instead of welding, such as a conductive adhesive or the installation of a conductive pin. For the sake of simplicity, the following description will be given taking as an example an electrical connection formed between the conductive portion 22 and the terminal post 12, and the welding position being the electrical connection position between the conductive portion 22 and the terminal post 12.

[0170] Specifically, the electrode post 12 includes a first end wall 12111 and a first side wall 12113, the first end wall 12111 being located on the side of the first side wall 12113 away from the active material coated portion 21, the first end wall 12111 and the first side wall 12113 surrounding each other forming a first accommodating groove 12110, and the electrical connection position between the conductive portion 22 and the electrode post 12 being located on the first end wall 12111 and / or the first side wall 12113. In other words, the conductive portion 22 may be welded to at least one of the first end wall 12111 and the first side wall 12113.

[0171] In the above technical solution, by locating the electrical connection between the conductive portion 22 and the electrode post 12 on at least one of the first end wall 12111 and the first side wall 12113, the first receiving groove 12110 not only accommodates at least a portion of the conductive portion 22, but the groove wall of the first receiving groove 12110 also establishes electrical connection with the conductive portion 22, thereby simplifying the structure of the electrode post 12, facilitating processing of the electrode post 12, simplifying the structure of the conductive portion 22, reducing redundancy in the conductive portion 22, and reducing the cost of the conductive portion 22. Furthermore, by utilizing the groove wall of the first receiving groove 12110 to establish electrical connection with the conductive portion 22, a relatively large electrical connection area between the conductive portion 22 and the electrode post 12 can be provided, which not only simplifies 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.

[0172] Furthermore, since the electrical connection position between the conductive portion 22 and the pole 12 is located within the first accommodating groove 12110, not only is it possible to prevent the electrical connection position from protruding outside the pole 12 and occupying space other than the pole 12, but the electrical connection position is protected by the pole 12, thereby improving the reliability and stability of the electrical connection between the conductive portion 22 and the pole 12.

[0173] In addition, in the embodiments of the present application, the first end wall 12111 is configured as a sealed structure without any through holes in order to isolate the first accommodating groove 12110 from the external space of the casing 11, thereby avoiding the problem of the electrolyte in the casing 11 leaking from the first accommodating groove 12110.

[0174] 12 and 13, in the embodiment of the present application, the local shape of the conductive portion 22 matches the local shape of the first end wall 12111 and is closely positioned to achieve electrical connection, so that the electrical connection position between the conductive portion 22 and the first end wall 12111 extends along the length or width direction of the first end wall 12111. For example, if the first end wall 12111 is flat, the local portion of the conductive portion 22 may also be flat and be closely positioned to the first end wall 12111, and the closely positioned position is electrically connected, for example, by welding. This increases the electrical connection area and improves the reliability and stability of the electrical connection.

[0175] Furthermore, when the electrical connection between the conductive portion 22 and the first end wall 12111 is by welding, the first end wall 12111 is positioned on the side of the first accommodating groove 12110 away from the active material application portion 21, which makes it easy to perform the welding operation, and for example, welding can be performed from the side of the pole 12 away from the active material application portion 21.

[0176] It should be noted that the shape of the first end wall 12111 is not limited, and may be, for example, a flat plate, an arcuate plate, etc. Wherein, when the first end wall 12111 has a flat structure, the first end wall 12111 is disposed at an angle with the first direction Z, and may be, for example, a flat plate structure perpendicular to the first direction Z, or may be, for example, an inclined plate structure not perpendicular to the first direction Z, but the inclination direction is not limited.

[0177] Of course, in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the first end wall 12111 does not necessarily extend along the length or width of the first end wall 12111, but may be, for example, a plurality of discretely located points, for example, the conductive portion 22 has a plurality of spaced apart portions that are each welded to the first end wall 12111, and the description thereof will be omitted here.

[0178] 14 again, in an embodiment of the present application, when the conductive portion 22 is electrically connected to the first end wall 12111, a first sinking groove 12112 can be provided in the first end wall 12111, and the sinking direction of the first sinking groove 12112 is a direction away from the active material applied portion 21. At least a portion of the position 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 can be provided within the first sinking groove 12112 and connected to a portion of the first end wall 12111 that defines the first sinking groove 12112.

[0179] In the above technical solution, on the one hand, the first sunken groove 12112 can be used to pre-position and limit the position of the conductive part 22 at the electrical connection position, which is advantageous not only for achieving accurate positioning and electrical connection and improving production efficiency, but also for improving the stability and reliability of the conductive part 22 and ensuring the stability and reliability of the charge and discharge processes of the battery cell 10. On the other hand, by providing the first sunken groove 12112 in the first end wall 12111, the wall thickness of the first end wall 12111 can be locally thinned, which is advantageous not only for welding but also for reducing the weight of the electrode post 12 and improving the weight-energy density of the battery cell 10.

[0180] In some alternative embodiments, a portion of the conductive portion 22 is fitted to the shape of the first side wall 12113 and closely attached to it, for example, if the first side wall 12113 is curved, a portion of the conductive portion 22 may also be curved and closely attached to the first side wall 12113, and an electrical connection (e.g., welding) may be made at the closely attached position so that the electrical connection position between the conductive portion 22 and the first side wall 12113 extends along the first side wall 12113. This increases the electrical connection area, thereby improving the reliability and stability of the electrical connection.

[0181] Of course, in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the first side wall 12113 does not necessarily extend along the first side wall 12113, but may be, for example, a plurality of discretely located points, for example, the conductive portion 22 having a plurality of spaced apart portions that are each welded to the first side wall 12113, and the description of which will be omitted here.

[0182] It should be noted that the number of first side walls 12113 is not limited and may be determined according to the shape of the first receiving groove 12110, as long as one end of each first side wall 12113 remote from the groove opening of the first receiving groove 12110 is connected to the first end wall 12111. For example, if the cross-sectional shape of the first receiving groove 12110 is circular or elliptical, the first end wall 12111 is also circular or elliptical, and the first side wall 12113 is one in number, has an annular shape, and is installed around the circumferential edge of the first end wall 12111. For example, if the cross-sectional shape of the first receiving groove 12110 is rectangular or racetrack-shaped, the first end wall 12111 is also rectangular or racetrack-shaped, and the first side walls 12113 are four in number, and are connected to the four sides of the first end wall 12111, respectively.

[0183] It should be further explained that the first accommodating groove 12110 is not limited to a 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 be present. In this case, the ends of each first side wall 12113 that are away from the groove mouth of the first accommodating groove 12110 may come together to define the first accommodating groove 12110 only by the multiple first side walls 12113. In this case, the conductive portion 22 is electrically connected to the first side wall 12113, and it is only necessary to ensure that the charging and discharging process of the battery cell 10 is carried out normally.

[0184] It should also be noted that in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the electrode post 12 does not have to be located within the first accommodating groove 12110. For example, the electrical connection position between the conductive portion 22 and the electrode post 12 may also be located on the electrode post inner end surface 122, in which case a portion of the conductive portion 22 is accommodated within the first accommodating groove 12110, saving some space and improving the energy density of the battery cell 10.

[0185] Referring again to Figures 13 and 14, in the embodiments of the present application, a first groove 126 may be further provided in the pole 12 if necessary, and the first groove 126 is located on the side of the pole 12 away from the active material application portion 21, i.e., the surface of the pole 12 away from the active material application portion 21 is the pole outer end surface 123, and the groove opening of the first groove 126 is formed on the pole outer end surface 123.

[0186] As can be understood, the first groove 126 is a groove body, and the groove body has a groove-like structure with a certain depth. When the electrode post 12 is installed on the upper end wall of the casing 11 and the electrode post outer end surface 123 is the upper surface of the electrode post 12, the first groove 126 is formed as a groove with an opening facing upward and groove walls that are concave downward (i.e., concave toward the rectangular shape adjacent to the battery core assembly 2). Also, when the electrode post 12 is installed on the lower end wall of the casing 11 and the electrode post outer end surface 123 is the lower surface of the electrode post 12, the first groove 126 is formed as a groove with an opening facing downward and groove walls that are concave upward (i.e., concave toward the rectangular shape adjacent to the battery core assembly 2).

[0187] In the above technical solution, on the one hand, the first groove 126 is provided on the pole 12, which further reduces the weight of the pole 12 and improves the weight energy density of the battery cells 10 and the battery 100. On the other hand, the first groove 126 is located on the outside of the pole 12, i.e., it opens toward the side of the pole 12 that is away from the inside of the casing 11. The first groove 126 can be used to accommodate or mount structural members electrically connected to each battery cell 10 in the battery 100, so as to fully utilize the space within the pole 12 and improve the space utilization rate and volumetric energy density of the battery 100.

[0188] Furthermore, by simultaneously providing the first receiving groove 12110 and the first groove 126 in the electrode post 12, the first groove 126 is located on the side of the first receiving groove 12110 away from the active material applied portion 21, and the first groove 126 opens in a direction away from the first receiving groove 12110. This makes it convenient to laser-weld the conductive portion 22 and the first end wall 12111 through the first groove 126 from the outside of the electrode post 12, i.e., from the side of the electrode post 12 away from the active material applied portion 21. That is, the electrical connection between the conductive portion 22 and the electrode post 12 can be easily achieved by external welding. In other words, the above structure and installation makes it easy to externally weld the electrode post 12 and the conductive portion 22 through the first groove 126, facilitating the processing and manufacturing of the battery cell 10 and reducing processing and manufacturing costs.

[0189] Furthermore, in order to easily and effectively weld the conductive portion 22 to the groove wall of the first accommodating groove 12110 through the first groove 126 and improve the reliability of the welding between the conductive portion 22 and the groove wall of the first accommodating groove 12110, in the embodiment of the present application, the portion between the first groove 126 and the first accommodating groove 12110 can be laser welded to the conductive portion 22, that is, the spacing portion 127 shown in Figure 14 is laser welded to the conductive portion 22 to realize an electrical connection between the battery core assembly 2 and the pole 12. The thickness of the spacing portion 127 of the pole post 12 located between the first groove 126 and the first accommodating groove 12110 is relatively thin, and the spacing portion 127 separates the first groove 126 from the first accommodating groove 12110. The wall surface of the spacing portion 127 closest to the active material application portion 21 can be the first end wall 12111. When the conductive portion 22 needs to be welded to the first end wall 12111, the relatively thin thickness of the spacing portion 127 is advantageous for welding the conductive portion 22 to the first end wall 12111 through the first groove 126, improving the convenience and reliability of the welding.

[0190] In some embodiments, the first accommodating groove 12110 may be configured with a cross-sectional shape whose length is greater than its width, such as a rectangle, oval, or racetrack shape, and the weld mark formed by welding the conductive portion 22 to the terminal post 12 may be an elongated weld mark parallel to the length direction of the first accommodating groove 12110 to improve the reliability of the weld and increase the current passing capacity. For example, when an elongated weld mark is formed by welding the conductive portion 22 to the first end wall 12111, the width of the weld mark may be 6 mm or more, and the distance between the weld mark and the first side wall 12113 may be 1 mm or more to ensure the convenience and reliability of the weld and maintain the current passing capacity of the battery cell 10.

[0191] 13 and 14, the casing assembly 1 may further include a groove cover 7, which is attached to the pole post 12 and seals the opening of the first groove 126.

[0192] In the above technical solution, by installing a groove cover 7 to seal the first groove 126, the electrode post 12 can achieve an indirect electrical connection with the bus member via the groove cover 7. The position and structure of the groove cover 7 make the electrical connection between the groove cover 7 and the bus member more convenient and increase the electrical connection area. Therefore, installing the groove cover 7 facilitates the electrical connection between adjacent battery cells 10 in the battery 100. Furthermore, because the electrical connection positions between the battery cells 10 are located on the groove cover 7, the electrical connection positions between the conductive parts 22 and the electrode post 12 can be separated by the first groove 126, reducing interference between them and further improving the stability and reliability of the battery cells 10.

[0193] It should be noted that based on the technical proposal that the accommodating portion 121 has a first accommodating groove 12110, the specific configuration of the battery core assembly 2 in the examples of the present application is not limited, and can include, for example, the following two embodiments, but is not limited thereto:

[0194] 12 to 14, in the first embodiment, when the accommodating portion 121 has the first accommodating groove 12110, at least a portion of the second converging portion 2213 may be accommodated in the first accommodating groove 12110.

[0195] In the above technical solution, the tab portion 221 includes a second converging portion 2213 formed by gathering and connecting multiple tab sheets 2211, so that at least a portion of the second converging portion 2213 is accommodated in the first accommodating groove 12110, which facilitates the connection between the conductive portion 22 and the pole 12, makes full use of the space in the pole 12, and improves the volumetric energy density of the battery cell 10.

[0196] 13 and 14 , in the first embodiment, at least a portion of the first converging portion 2212 is accommodated in the first accommodating groove 12110. In the above technical solution, at least a portion of the first converging portion 2212 and at least a portion of the second converging portion 2213 of the tab portion 221 are both accommodated in the first accommodating groove 12110, thereby making better use of the space within the pole 12 to accommodate a larger-sized active material applied portion 21, further reducing the space occupied by the tab portion 221 within the casing 11, improving the volumetric energy density of the battery cell 10, and better reducing the redundancy of the tab portion 221 within the casing 11, thereby further reducing the probability of a short circuit between the tab portion 221 and the active material applied portion 21.

[0197] In this embodiment, the second converging portion 2213 is electrically connected directly or indirectly to the electrode post 12. For example, referring to Fig. 13, when the second converging portion 2213 is directly electrically connected to the electrode post 12, for example, when the second converging portion 2213 is welded (e.g., laser welded) to the electrode post 12, the structure of the battery core assembly 2 can be simplified, the number of components can be reduced, the assembly flow can be simplified, and assembly efficiency can be improved. Meanwhile, the method and position of the direct electrical connection between the second converging portion 2213 and the electrode post 12 are not limited. For example, the electrical connection position between the second converging portion 2213 and the pole 12 may be located on the first end wall 12111 and / or the first side wall 12113, and further, the electrical connection position between the second converging portion 2213 and the first end wall 12111 may extend along the length or width direction of the first end wall 12111, and further, the first end wall 12111 may have a first sunken groove 12112, and the electrical connection position between the second converging portion 2213 and the first end wall 12111 may be located within the first sunken groove 12112, etc. For corresponding technical effects, please refer to the descriptions of the above examples, and the description thereof will be omitted here.

[0198] As an optional technical solution, an adapter sheet 222 may be installed on the conductive portion 22 as needed, in which case the second converging portion 2213 is indirectly electrically connected to the pole 12. Specifically, referring to FIG. 14 , when the conductive portion 22 includes the adapter sheet 222, at least a portion of the adapter sheet 222 is accommodated in the first accommodating groove 12110, and in this example, at least a portion of the second converging portion 2213 is also accommodated in the first accommodating groove 12110, but the first converging portion 2212 may or may not be accommodated in the first accommodating groove 12110.

[0199] In the above technical solution, by accommodating at least a portion of the second converging portion 2213 and at least a portion of the adapter sheet 222 in the first accommodating groove 12110, the space within the electrode post 12 can be more fully utilized, the space occupied by the conductive part 22 in the casing 11 can be further reduced, and the volumetric energy density of the battery cell 10 can be improved. On the other hand, if at least a portion of the first converging portion 2212, at least a portion of the second converging portion 2213, and at least a portion of the adapter sheet 222 are all accommodated in the first accommodating groove 12110, the space within the electrode post 12 can be more fully utilized, the space occupied by the conductive part 22 in the casing 11 can be more effectively reduced, and the volumetric energy density of the battery cell 10 can be further improved.

[0200] The method and location of the direct electrical connection between the adapter sheet 222 and the terminal post 12 are not limited. For example, the adapter sheet 222 and the terminal post 12 are electrically connected by welding. For example, the electrical connection position between the adapter sheet 222 and the terminal post 12 may be located on the first end wall 12111 and / or the first side wall 12113. The electrical connection position between the adapter sheet 222 and the first end wall 12111 may extend along the length or width direction of the first end wall 12111. Furthermore, the first end wall 12111 may have a first recessed groove 12112, and the electrical connection position between the adapter sheet 222 and the first end wall 12111 may be located within the first recessed groove 12112. For corresponding technical effects, refer to the descriptions of the above embodiments, and the description thereof will be omitted here. When the electrical connection position between the adapter sheet 222 and the pole 12 is located on the first end wall 12111 and / or the first side wall 12113, at least a portion of the adapter sheet 222 is accommodated in the first accommodating groove 12110, thereby simplifying the structure of the adapter sheet 222, reducing redundancy, and reducing costs.

[0201] Referring to Figure 14, in the second embodiment, the conductive portion 22 includes an adapter sheet 222 for electrically connecting the second converging portion 2213 and the pole 12, the accommodating portion 121 has a first accommodating groove 12110, and at least a portion of the adapter sheet 222 is accommodated in the first accommodating groove 12110.

[0202] In the above technical solution, the second embodiment differs from the technical solution including the adapter sheet 222 of the first embodiment in that in the second embodiment, at least a portion of the adapter sheet 222 is accommodated in the first accommodating groove 12110, but the relative position of the tab portion 221 and the first accommodating groove 12110 is not limited, that is, at least a portion of the tab portion 221 can be accommodated in the first accommodating groove 12110, or the tab portion 221 can be located completely outside the first accommodating groove 12110, thereby meeting different structural design requirements.

[0203] In the above technical solution, by accommodating at least a portion of the adapter sheet 222 in the first accommodating groove 12110, the adapter sheet 222 can occupy space within the pole 12, thereby reducing the space occupied by the adapter sheet 222 within the casing 11 to accommodate a larger-sized active material application portion 21, improving the volumetric energy density of the battery cell 10, and reducing the probability of a short circuit between the adapter sheet 222 and the active material application portion 21, thereby reducing the risk of a short circuit of the battery core assembly 2, so as to improve the stability and reliability of the battery cell 10.

[0204] Furthermore, by using the adapter sheet 222 to achieve an indirect electrical connection between the second converging portion 2213 and the electrode post 12, the adapter sheet 222 can be welded to the electrode post 12 using a portion that avoids the second converging portion 2213, which strengthens the weld between the adapter sheet 222 and the electrode post 12, reduces the risk of weld cracking, and further improves the reliability and stability of the battery cell 10. At the same time, by electrically connecting the electrode post 12 and the tab sheet 2211 via the adapter sheet 222, the structure of the tab sheet 2211 can also be simplified.

[0205] For example, in some selectable embodiments, for example, in the above-described Example 1 or the following third embodiment, when the second converging portion 2213 is directly electrically connected to the electrode post 12, the conductive portion 22 may be composed of only the positive and negative electrode tabs of each electrode assembly 2 a. For example, in some other embodiments, for example, in the above-described Example 1 or Example 2, or the following third or fourth embodiment, when the second converging portion 2213 and the electrode post 12 are indirectly electrically connected via the adapter sheet 222, the conductive portion 22 may be composed of the positive and negative electrode tabs of each electrode assembly 2 a and each adapter sheet 222.

[0206] It should be noted that the receiving portion 121 in the embodiment of the present application does not necessarily have to have the first receiving groove 12110, and for example, some other alternative embodiments are shown below.

[0207] For example, Figure 15 is a schematic local cross-sectional view of a battery cell 10 provided by some embodiments of the present application. Referring to Figure 15, in the embodiment of the present application, the accommodating portion 121 may be configured to include a second accommodating groove 12120, the surface of the pole 12 facing away from the active material coating portion 21 is the pole outer end surface 123, the groove opening of the second accommodating groove 12120 is formed in the pole outer end surface 123, the second accommodating groove 12120 communicates with the inside of the casing 11 through the first through hole 12130, and the conductive portion 22 is drilled in the first through hole 12130 and at least a portion of it is accommodated in the second accommodating groove 12120.

[0208] As can be understood, the second accommodating groove 12120 is a groove body, which has a groove-like structure with a certain depth. For example, when the electrode post 12 is installed on the upper end wall of the casing 11 and the electrode post outer end surface 123 is the upper surface of the electrode post 12, the second accommodating groove 12120 is formed as an accommodating groove with an opening facing upward and groove walls recessed downward. Also, when the electrode post 12 is installed on the lower end wall of the casing 11 and the electrode post outer end surface 123 is the lower surface of the electrode post 12, the second accommodating groove 12120 is formed as an accommodating groove with an opening facing downward and groove walls recessed upward.

[0209] In the above technical solution, referring to FIG. 15, on the one hand, by installing the second accommodating groove 12120 in the pole 12, the weight of the pole 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, since the groove opening of the second accommodating groove 12120 is formed on the outer end surface 123 of the pole 12, and the outer end surface 123 is the surface of the pole 12 facing away from the active material applied portion 21, the second accommodating groove 12120 can open in a direction away from the active material applied portion 21. In this way, when at least a portion of the conductive portion 22 is accommodated in the second accommodating groove 12120, the groove opening of the second accommodating groove 12120 makes it easy to store and organize the conductive portion 22, and the groove opening of the second accommodating groove 12120 makes it easy to electrically connect the conductive portion 22 to the pole 12, thereby reducing the difficulty of producing the battery cell 10 and improving the production efficiency of the battery cell 10.

[0210] At the same time, since the second accommodating groove 12120 can pass through the first through-hole 12130 and communicate with the inside of the casing 11, the second accommodating groove 12120 can be used as a buffering and temporary storage structure for the electrolyte. The casing 11 can accommodate more electrolyte. Since the electrolyte is consumed during the charging and discharging process of the battery cell 10, the more electrolyte there is, the longer the service life of the battery cell 10 can be. Furthermore, since the second accommodating groove 12120 can pass through the first through-hole 12130 and communicate with the inside of the casing 11, the second accommodating groove 12120 can also be used as a buffering structure for the gas generated inside the battery core assembly 2, which can reduce the expansion of the battery cell 10 and improve the reliability and stability of the battery cell 10.

[0211] It should be noted that when the accommodating portion 121 has a second accommodating groove 12120, the conductive portion 22 is drilled in the first through hole 12130, and at least a portion of the conductive portion 22 is accommodated in the second accommodating groove 12120, the electrical connection position between the conductive portion 22 and the pole 12 is not limited.

[0212] For example, when the conductive portion 22 is drilled in the first through hole 12130 and at least a portion of it is accommodated in the second accommodating groove 12120, in the embodiment of the present application, the electrical connection position between the conductive portion 22 and the pole 12 is located on the hole wall of the first through hole 12130 formed in the pole 12.

[0213] In the above technical solution, the electrical connection position between the conductive part 22 and the electrode post 12 is located on the hole wall of the first through hole 12130, so that the electrical connection operation between the conductive part 22 and the electrode post 12 can be easily performed through the second accommodating groove 12120. Furthermore, when the electrical connection area between the conductive part 22 and the electrode post 12 is relatively large, the sealing cost can be saved, the leakage of electrolyte can be reduced, and the sealing material can be saved, so that the sealing material can be saved.

[0214] Specifically, by welding the conductive part 22 to the wall of the first through hole 12130 at the position where the first through hole 12130 and the second accommodating groove 12120 are connected, operation is made easier, and by controlling the welding marks, the welding marks and the conductive part 22 can be used to seal the first through hole 12130, thereby improving the problem of the electrolyte in the casing 11 leaking from the first through hole 12130.

[0215] Also, for example, when the conductive portion 22 is drilled in the first through-hole 12130 and at least a portion thereof is accommodated in the second accommodating groove 12120, in some other embodiments of the present application, the electrical connection position between the conductive portion 22 and the electrode post 12 may be located on the groove wall of the second accommodating groove 12120 formed in the electrode post 12. This facilitates the electrical connection operation and, for example, when the conductive portion 22 is welded to the groove wall of the second accommodating groove 12120 formed in the electrode post 12, prevents conductive particles produced by welding from entering the casing 11 and causing problems such as short circuits.

[0216] Specifically, Figure 16 is a local cross-sectional schematic diagram of a battery cell 10 provided by some embodiments of the present application. Referring to Figures 15 and 16, the 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 application portion 21, the second end wall 12121 and the second side wall 12123 surround each other to form a second accommodating groove 12120, a first through hole 12130 is opened in the second end wall 12121, and the electrical connection position between the conductive portion 22 and the pole 12 is located on the second end wall 12121 and / or the second side wall 12123.

[0217] More specifically, the conductive portion 22 and the electrode post 12 can be electrically connected by welding, and therefore the welding position is the electrical connection position between the conductive portion 22 and the electrode post 12. In other embodiments of the present application, the conductive portion 22 and the electrode post 12 can be electrically connected by other methods instead of welding, such as by using a conductive adhesive or installing a conductive pin, and the description thereof will be omitted here.

[0218] For the sake of simplicity, the following description will be given taking as an example an electrical connection formed between the conductive portion 22 and the electrode post 12, and the welding position being the electrical connection position between the conductive portion 22 and the electrode post 12. For example, in some embodiments, the electrical connection position between the conductive portion 22 and the electrode post 12 may be located on 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.

[0219] In the above technical solution, the electrical connection position between the conductive portion 22 and the electrode post 12 is located on at least one of the second end wall 12121 and the second side wall 12123. This allows the second accommodating groove 12120 to accommodate at least a portion of the conductive portion 22, and the groove wall of the second accommodating groove 12120 to establish electrical connection with the conductive portion 22, thereby simplifying the structure of the electrode post 12 and facilitating processing of the electrode post 12. Furthermore, the first through-hole 12130 is formed in the second end wall 12121, which allows the conductive portion 22 to easily extend into the second accommodating groove 12120 through the first through-hole 12130. This simplifies the structure of the conductive portion 22, reduces redundancy of the conductive portion 22, and reduces the cost of the conductive portion 22. Furthermore, due to the opening direction of the groove opening of the second accommodating groove 12120, the electrical connection operation between the conductive part 22 and the groove wall of the second accommodating groove 12120 can be easily performed through the groove opening of the second accommodating groove 12120, reducing the difficulty of the electrical connection. Furthermore, the electrical connection with the conductive part 22 can be realized using the groove wall of the second accommodating groove 12120, thereby making the electrical connection area between the conductive part 22 and the pole 12 relatively large, improving the reliability and stability of the electrical connection and ultimately improving the performance of the battery cell 10.

[0220] Furthermore, since the electrical connection position between the conductive portion 22 and the pole 12 is located within the second accommodating groove 12120, not only is it possible to prevent the electrical connection position from protruding outside the pole 12 and occupying space other than the pole 12, but the electrical connection position is protected by the pole 12, thereby improving the reliability and stability of the electrical connection between the conductive portion 22 and the pole 12.

[0221] 15 and 16, in the embodiment of the present application, the local shape of the conductive portion 22 matches the local shape of the second end wall 12121 and is closely arranged to achieve electrical connection, so that the electrical connection position between the conductive portion 22 and the second end wall 12121 extends along the length or width direction of the second end wall 12121. For example, if the second end wall 12121 is flat, the local portion of the conductive portion 22 may also be flat and be closely arranged to the second end wall 12121, and the closely arranged position may be electrically connected by, for example, welding. This increases the electrical connection area and improves the reliability and stability of the electrical connection.

[0222] It should be noted that the shape of the second end wall 12121 is not limited, and may be, for example, a flat plate, an arcuate plate, etc. Wherein, when the second end wall 12121 has a flat plate structure, the second end wall 12121 is disposed at an angle with the first direction Z, and may be, for example, a flat plate structure perpendicular to the first direction Z, or may be, for example, an inclined flat plate structure not perpendicular to the first direction Z, but the inclination direction is not limited.

[0223] 15 and 16, when the second end wall 12121 has a flat plate-like structure, the angle θ between the second end wall 12121 and the first direction Z is equal to 90°, that is, the second end wall 12121 and the active material coating portion 21 are equidistant from each other along the direction from the first through-hole 12130 to the second side wall 12123. This facilitates welding of the conductive portion 22 and the second end wall 12121.

[0224] 17 is a schematic local cross-sectional view of a battery cell 10 provided according to some embodiments of the present application. Referring to FIG. 17, the angle θ between the second end wall 12121 and the first direction Z is greater than 90°. That is, the second end wall 12121 extends at an angle from the first through hole 12130 to the second side wall 12123 toward the active material coated portion 21. This allows the conductive portion 22 to extend a longer distance along the second end wall 12121, thereby improving the reliability of the electrical connection. For example, the angle θ between the second end wall 12121 and the first direction Z may be 90° to 145°, for example, 100°, 110°, 120°, 130°, 140°, etc., which, on the one hand, makes the second end wall 12121 easy to process and facilitates electrical connection with the conductive portion 22, and, on the other hand, allows the space within the pole post 12 to be relatively fully utilized to accommodate the conductive portion 22.

[0225] 18 is a schematic local cross-sectional view of a battery cell 10 provided according to some embodiments of the present application. Referring to FIG. 18, the angle θ between the second end wall 12121 and the first direction Z is less than 90°, that is, the second end wall 12121 extends at an angle away from the active material-coated portion 21 along the direction from the first through-hole 12130 to the second side wall 12123. This allows the conductive portion 22 to extend a longer distance along the second end wall 12121, thereby improving the reliability of the electrical connection. For example, the angle θ between the second end wall 12121 and the first direction Z may be 45° to 90°, for example, 50°, 60°, 70°, 80°, etc., which, on the one hand, makes the second end wall 12121 easier to process and facilitates electrical connection with the conductive portion 22, and, on the other hand, allows the space within the pole post 12 to be relatively fully utilized to accommodate the conductive portion 22.

[0226] Of course, in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the second end wall 12121 does not necessarily extend along the length or width of the second end wall 12121, but may be a plurality of discretely arranged points, for example, the conductive portion 22 has a plurality of spaced apart portions that are respectively welded to the second end wall 12121, and the description thereof will be omitted here.

[0227] 16 again, regardless of the specific value of the angle θ between the second end wall 12121 and the first direction Z, in any embodiment of the present application, when the conductive portion 22 is electrically connected to the second end wall 12121, a second sunken groove 12122 can be provided in the second end wall 12121 as needed. The second sunken groove 12122 is a recessed groove formed by sinking the second end wall 12121 toward one end that is close to the active material application portion. At least a portion of the position where the conductive portion 22 is electrically connected to the second end wall 12121 is located within the second sunken groove 12122.

[0228] In the above technical solution, the portion of the conductive part 22 located within the second sunken groove 12122 is installed to fit the shape of the second sunken groove 12122 and is installed closely to achieve electrical connection, thereby using the second sunken groove 12122 to achieve pre-positioning and position restriction of the electrical connection position of the conductive part 22, allowing for accurate positioning and electrical connection, which is beneficial to improving production efficiency and can improve the stability and reliability of the electrical connection position, thereby ensuring the reliability and stability of the charging and discharging operations of the battery cell 10.

[0229] It should be noted that in the embodiments of the present application, a portion of the conductive portion 22 can be fitted to the shape of the second side wall 12123 and be closely fitted to it, for example, if the second side wall 12123 is curved, a portion of the conductive portion 22 can also be curved and be closely fitted to the second side wall 12123, and the electrical connection (e.g., welding) can be performed at the closely fitted position so that the electrical connection position between the conductive portion 22 and the second side wall 12123 extends along the second side wall 12123. This increases the electrical connection area, thereby improving the reliability and stability of the electrical connection.

[0230] It should be further explained that in other embodiments of the present application, the electrical connection position between the conductive portion 22 and the second side wall 12123 does not necessarily extend along the second side wall 12123, but may be, for example, a plurality of discretely arranged points, for example, the conductive portion 22 has a plurality of spaced apart portions that are each welded to the second side wall 12123, and the description of which will be omitted here.

[0231] As can be understood, the number of second side walls 12123 is not limited and may be determined according to the shape of the second receiving groove 12120, as long as one end of each second side wall 12123 remote from the groove opening of the second receiving groove 12120 is connected to the second end wall 12121. For example, if the cross-sectional shape of the second receiving groove 12120 is circular or elliptical, the second end wall 12121 is also circular or elliptical, and there is one second side wall 12123, which is annular and installed around the circumferential edge of the second end wall 12121. For example, if the cross-sectional shape of the second receiving groove 12120 is rectangular or racetrack-shaped, the second end wall 12121 is also rectangular or racetrack-shaped, and there are four second side walls 12123, which are connected to the four sides of the second end wall 12121, respectively.

[0232] It should be further explained that the second accommodating groove 12120 is not limited to a shape defined by the second end wall 12121 and the second side wall 12123. For example, in some embodiments, Figure 19 is a schematic local cross-sectional view of a battery cell 10 provided by some embodiments of the present application. Referring to Figure 19, one end of each second side wall 12123 away from the groove mouth of the second accommodating groove 12120 all extends to the first through hole 12130, so that the second accommodating groove 12120 is defined only by a plurality of second side walls 12123. In this case, the conductive portion 22 can be electrically connected to the second side wall 12123.

[0233] In some embodiments, referring to FIG. 30 , the receiving portion 121 may have a third receiving groove 12140 and a second receiving groove 12120 at the same time, the second receiving groove 12120 is located on the side of the third receiving groove 12140 away from the active material application portion 21, the third receiving groove 12140 is a groove body, and the groove body is a groove-like structure with a certain depth, the groove opening of the third receiving groove 12140 is formed on the electrode post inner end surface 122 on the side close to the active material application portion 21 of the electrode post 12, and the groove opening of the second receiving groove 12120 is formed on the side of the electrode post inner end surface 122 close to the active material application portion 21 of the electrode post 12. The third accommodating groove 12140 and the second accommodating groove 12120 are connected via the first through hole 12130. In this case, a part of the conductive part 22 is located in the third accommodating groove 12140, and the conductive part 22 is further drilled into the first through hole 12130, and another part of the conductive part 22 is located in the second accommodating groove 12120. This makes it possible to make relatively full use of the space within the pole 12 and reduce the space occupied by the conductive part 22 within the casing 11.

[0234] 19, when the conductive portion 22 is connected to the second end wall 12121 or the second side wall 12123 by laser welding, the angle β between the portion of the conductive portion 22 used for welding and the axis of the first through hole 12130 can be set to be greater than 5°, which reduces the problem of the laser entering the casing 11 through the first through hole 12130 and is advantageous for the welding operation. Furthermore, when the angle β between the portion of the conductive portion 22 used for welding and the axis of the first through hole 12130 is close to 5°, edge welding can be used, and the other portions can be connected by lap welding.

[0235] 15 again, in the embodiment of the present application, the method of connecting the terminal post 12 and the casing 11 is not limited and may be, for example, welding or riveting. For example, when the two are fitted together by riveting, the casing 11 has a mounting hole 113 and the terminal post 12 is attached to the mounting hole 113 by riveting. Of course, it can be understood that when the two are fitted together by welding or another method, the casing 11 may have a mounting hole 113 so that the terminal post 12 is attached to the casing 11 through the mounting hole 113.

[0236] Alternatively, referring to FIG. 15, the second accommodating groove 12120 may be installed corresponding to the position of the mounting hole 113, or in a projection plane perpendicular to the first direction Z, the orthogonal projection of the second accommodating groove 12120 is located within the orthogonal projection range of the mounting hole 113, so that the second accommodating groove 12120 can have a relatively large depth to accommodate more conductive parts 22, and thus the space occupied by the conductive parts 22 in the casing 11 can be more significantly reduced.

[0237] In some embodiments, referring to FIG. 15 , when the casing 11 has a mounting hole 113 and the pole 12 is mounted in the mounting hole 113, the depth H3 of the second accommodating groove 12120 along the first direction Z is greater than or equal to the minimum distance H4 from the pole outer end surface 123 to the mounting hole 113.

[0238] It should be noted that the specific shape of the second receiving groove 12120 is not limited, and may be a regular or irregular shape, such as a cylindrical groove having a rectangular, elliptical, or racetrack cross section, a trapezoidal groove having a rectangular cross section with gradually varying cross-sectional dimensions, a hemispherical groove having a circular cross section with gradually varying cross-sectional dimensions, or a semi-elliptical groove having an elliptical cross section with gradually varying cross-sectional dimensions. It should be noted that the racetrack shape described herein refers to a shape in which the two short sides of a rectangle are replaced with convex curves, and for example, refers to the shape shown in FIG. 21(b).

[0239] Therefore, the depth H3 of the second accommodating groove 12120 refers to the maximum depth of the second accommodating groove 12120 along the first direction Z. In the first direction Z, the depth H3 of the second accommodating groove 12120 is equal to or greater than the minimum distance H4 from the pole outer end surface 123 to the mounting hole 113. This allows the volume of the pole 12 to be fully utilized, and the second accommodating groove 12120 has a relatively large depth, which is advantageous for accommodating more conductive parts 22 and thus significantly reducing the space occupied by the conductive parts 22 within the casing 11, further improving the energy density of the battery cell 10 and reducing the redundancy of the conductive parts 22 within the casing 11. At the same time, the relatively large depth of the second accommodating groove 12120 also allows it to accommodate gas generated by the battery core assembly 2, ensuring the reliability and stability of the battery cell 10, and allowing it to accommodate more electrolyte, thereby ensuring the service life of the battery cell 10.

[0240] 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 (referred to as a third volume V4) for receiving the conductive portion 22 is 298 mm 3 or more, so that the second accommodating groove 12120 can have a relatively sufficient space to accommodate the conductive portion 22 and facilitate welding of the conductive portion 22 to the terminal post 12. On the other hand, if the third volume V4 of the second accommodating groove 12120 is 298 mm 3If the third volume V4 of the second accommodating groove 12120 is less than 300 mm, the accommodating capacity of the second accommodating groove 12120 for the conductive part 22 will be relatively weak, and the welding between the conductive part 22 and the terminal post 12 will be difficult. For example, 3 , 400mm 3 , 500mm 3 , 600mm 3 , 700mm 3 , 800mm 3 , 1000mm 3 etc. may also be used.

[0241] It should be noted that the third volume V4 of the second receiving groove 12120 is the difference between the total volume V5 of the second receiving groove 12120 and the volume (referred to as a fourth volume V6) required for the second receiving groove 12120 to receive other components (e.g., the first cover plate 13 and the second cover plate 14 described herein) other than the conductive portion 22, i.e., V4 = V5 - V6. For example, in some specific examples, the total volume V5 of the second receiving groove 12120 is 1400 mm 3 ~1500mm 3 This allows the second accommodating groove 12120 to have more sufficient space to accommodate the conductive portion 22 and other components. For example, the total volume V5 of the second accommodating groove 12120 is 1420 mm 3 , 1440mm 3 , 1460mm 3 , 1480mm 3 , 1490mm 3 etc. may also be used.

[0242] In the embodiments of the present application, there are no limitations on the shape of the first through holes 12130, the number of the first through holes 12130, and the relative positional relationship between the first through holes 12130 and the second receiving grooves 12120.

[0243] 20 is an enlarged view of a portion B in FIG. 3, and FIG. 21 is an orthogonal projection view of various types of pole posts 12 provided by some embodiments of the present application. Referring to FIGS. 20 and 21, in the embodiments of the present application, the shape of the first through hole 12130 may be elongated to match the sheet-like local shape of the conductive portion 22, thereby favoring the penetration of the sheet-like local portion of the conductive portion 22. At the same time, when the first through hole 12130 is elongated, the second receiving groove 12120 may be configured with a shape whose cross-sectional length is greater than its width, such as a rectangle, an oval, or a racetrack shape. In this case, the length direction of the first through hole 12130 can be aligned with the cross-sectional length direction of the second receiving groove 12120, thereby making full use of space. Note that the weld mark formed by welding the conductive portion 22 to the electrode post 12 may be an elongated weld mark parallel to the length direction of the first through hole 12130, in order to improve the reliability of the weld and increase the current passing capacity. For example, when an elongated weld mark is formed by welding the conductive portion 22 to the second end wall 12121, the width of the weld mark may be 6 mm or more, and the distance between the weld mark and the second side wall 12123 may be 1 mm or more, in order to ensure the convenience and reliability of the weld and at the same time maintain the current passing capacity of the battery cell 10.

[0244] Regarding the size and number of the first through-holes 12130, in the embodiments of the present application, the opening size and specific position of the first through-holes 12130 in the second accommodating groove 12120 are not limited, and related designs can be made according to the number of first through-holes 12130. For example, the width of the first through-hole 12130 may be 2 mm or more, which is advantageous for the passage of the conductive part 22. For example, when only one first through-hole 12130 is opened in the second accommodating groove 12120, in some examples, as shown in FIGS. 20 and 21, the first through-hole 12130 may be disposed centrally relative to the second accommodating groove 12120. In other examples, as shown in FIG. 22, which is a schematic local cross-sectional view of a battery cell 10 provided according to some embodiments of the present application, the first through-hole 12130 may be disposed off-center relative to the second accommodating groove 12120. For example, in some embodiments, referring to FIG. 22, the first through hole 12130 can be opened at the edge of the second end wall 12121 so as to be located close to the second side wall 12123, thereby increasing the available area of ​​the second end wall 12121 and increasing the welding area between the conductive portion 22 and the second end wall 12121.

[0245] As will be understood, after the conductive portion 22 passes through the first through hole 12130, it is folded back so as to fit closely to the second end wall 12121, but the folding direction is not limited. For example, if the first through hole 12130 is centrally located relative to the second accommodating groove 12120, the conductive portion 22 can be folded back toward any side of the first through hole 12130 after passing through the first through hole 12130 (see FIG. 20 ), thereby appropriately reducing the size of the second accommodating groove 12120 and improving the compactness and structural strength of the structure. Alternatively, FIG. 23 is a schematic cross-sectional view of a battery cell 10 provided according to some embodiments of the present application. Referring to FIG. 23 , after the conductive portion 22 passes through the first through hole 12130, it can be folded back toward opposite sides at the same time, thereby reducing the thickness of the welding point, reducing heat input during welding, and reducing problems such as particle scattering.

[0246] For example, when the second accommodating groove 12120 has a plurality of first through holes 12130, the plurality of first through holes 12130 are arranged in parallel or approximately parallel longitudinal directions to fully utilize the space. In this case, the folding direction of the conductive portion 22 after passing through the first through holes 12130 can be determined based on the relative positional relationship of the plurality of first through holes 12130. For example, referring to FIG. 10 , when the second accommodating groove 12120 has two first through holes 12130 that are spaced apart, the two conductive portions 22 passing through the two first through holes 12130 can be folded back toward each other, and when the second accommodating groove 12120 has two first through holes 12130 that are spaced apart, the two conductive portions 22 passing through the two first through holes 12130 can be folded back toward each other.

[0247] It can be understood that when there are multiple first through holes 12130 opened in the second accommodating groove 12120, the number of pole posts 12 can be appropriately reduced, thereby reducing costs and processes.

[0248] Also, in some embodiments, referring to Figures 22 and 23, the first through hole 12130 can be positioned centrally relative to the active material application portion 21, but the position of the first through hole 12130 relative to the second accommodating groove 12120 is not limited and may be positioned centrally or off-center, and since the first through hole 12130 is positioned centrally relative to the active material application portion 21, the conductive portion 22 can converge in accordance with the center line position of the active material application portion 21.

[0249] 23 , in some embodiments, a seal 6 may be installed in the first through-hole 12130 to address the problem of electrolyte in the casing 11 leaking through the first through-hole 12130. The material, shape, and connection method of the seal 6 with the first through-hole 12130 are not limited. For example, the seal 6 may be a metal member made of the same material as the electrode post 12 or the conductive part 22, and may be welded to the wall of the first through-hole 12130 of the electrode post 12 to seal the first through-hole 12130. For example, the seal 6 may be made of rubber or plastic, and may be inserted into the first through-hole 12130 and tightly fitted thereto to seal the first through-hole 12130. In the embodiments of the present application, any of these may be designed according to actual needs and are not limited thereto.

[0250] Figure 24 is a structural exploded view of a battery cell 10 provided according to some embodiments of the present application, Figure 25 is a local cross-sectional schematic view of a casing assembly 1 provided according to some embodiments of the present application, and Figure 26 is a structural exploded view of the casing assembly 1 shown in Figure 25. Referring to Figures 24, 25 and 26, in the embodiments of the present application, when the accommodating portion 121 has the second accommodating groove 12120 of any one of the above embodiments, optionally, the casing assembly 1 may further include a first cover plate 13 that fits into the electrode post 12 and seals the groove opening of the second accommodating groove 12120, and the first cover plate 13 is electrically connected to the electrode post 12.

[0251] In the above technical proposal, by installing the first cover plate 13 so as to seal the groove opening of the second accommodating groove 12120, it is possible to prevent the electrolyte in the casing 11 from leaking from the groove opening of the second accommodating groove 12120. Furthermore, since the first cover plate 13 seals the groove opening of the second accommodating groove 12120 and is electrically connected to the pole 12, it is possible to easily realize an indirect electrical connection between the pole 12 and the bus member using the first cover plate 13, which is advantageous for increasing the connection area of ​​the electrical connection point and therefore reducing the resistance of the electrical connection point.

[0252] It should be noted that the method and position of fitting the first cover plate 13 and the terminal post 12 are not limited as long as the groove opening of the second accommodating groove 12120 of the first cover plate 13 can be sealed. For example, in some embodiments, referring to Fig. 24, the first cover plate 13 may be welded to the terminal post 12, and during processing, the conductive portion 22 may first be passed through the first through-hole 12130 and welded to the groove wall of the second accommodating groove 12120, and then the first cover plate 13 and the terminal post 12 may be welded to seal the groove opening of the second accommodating groove 12120.

[0253] It should be further explained that the specific configuration of the first cover plate 13 is not limited. For example, in some selectable embodiments, Fig. 27 is a structural exploded view of the first cover plate 13 shown in Fig. 26. Referring to Figs. 25 to 27, 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 fitted to and electrically connected with the pole 12, and the second conductive member 132 is fitted to and electrically connected with the first conductive member 131.

[0254] In the above technical solution, the first cover plate 13 is installed in a composite form, and the first conductive member 131 is installed so that it is made of the same material as the electrode post 12, which facilitates electrical connection between the first conductive member 131 and the electrode post 12. For example, the first conductive member 131 can be easily and reliably connected to the electrode post 12 by welding. Furthermore, because the second conductive member 132 and the first conductive member 131 are made of a different material, the second conductive member 132 can be easily used to electrically connect to bus members made of a different material from the electrode post 12. For example, the second conductive member 132 can be easily and reliably connected to bus members made of the same material as the second conductive member 132 by welding.

[0255] For example, if the electrode post 12 is a negative electrode post, the electrode post 12 is a copper post, and the bus member is an aluminum sheet, the first conductive member 131 can be made of copper and the second conductive member 132 can be made of aluminum. In this case, the electrode post 12 and the first conductive member 131 can be made of the same material and effectively welded together, and the second conductive member 132 and the bus member can be made of the same material and effectively welded together, thereby effectively realizing an indirect electrical connection between the electrode post 12 and the bus member via the first cover plate 13. In addition, the electrode post 12 and the first conductive member 131 are welded together, which has excellent fluidity, is less likely to crack, and is advantageous for improving the sealing effect of the welded parts.

[0256] 25 to 27 again, in some optional examples, the first conductive member 131 is located between the second accommodating groove 12120 and the second conductive member 132. In the above technical solution, since the first conductive member 131 is located between the second accommodating groove 12120 and the second conductive member 132, the second accommodating groove 12120 and the second conductive member 132 can be separated from each other. As a result, when the electrolyte in the casing 11 enters the second accommodating groove 12120 through the first through-hole 12130, the first conductive member 131 is used to prevent the electrolyte in that portion from contacting the second conductive member 132, thereby solving the problem of corrosion of the second conductive member 132 by the electrolyte.

[0257] It should be noted that the method of fitting the first conductive member 131 and the second conductive member 132 is not limited. For example, in some embodiments, referring to FIGS. 25 to 27, the first conductive member 131 has a second groove 1311, the second conductive member 132 is fitted into the second groove 1311, and the groove opening of the second groove 1311 is formed on the surface of the first conductive member 131 away from the second receiving groove 12120 so that the second conductive member 132 is exposed from the groove opening of the second groove 1311. Alternatively, in other embodiments, the method of connecting the first conductive member 131 and the second conductive member 132 may be a fastening connection, an engagement, or the like.

[0258] As should be further explained, when the second conductive member 132 is "exposed" from the groove opening of the second groove 1311, it is sufficient that the first conductive member 131 does not block the second conductive member 132 at the groove opening position of the second groove 1311, and the second conductive member 132 does not have to protrude from the groove opening of the second groove 1311. For example, the second conductive member 132 may be positioned flush with the surface of the first conductive member 131 facing away from the second accommodating groove 12120, or the second conductive member 132 may protrude from the surface of the first conductive member 131 facing away from the second accommodating groove 12120.

[0259] In the above technical solution, the second conductive member 132 is fitted into the first conductive member 131, which reduces the difficulty of assembling the first conductive member 131 and the second conductive member 132 and improves the stability and convenience of the fitting of the first conductive member 131 and the second conductive member 132. It also reduces the thickness of the first cover plate 13, reducing the space occupied by the first cover plate 13 and improving the space utilization rate of the battery cell 10. Furthermore, the second conductive member 132 can be exposed from the surface of the first conductive member 131 away from the second receiving groove 12120 through the opening of the second groove 1311, which is advantageous for achieving electrical connection between the second conductive member 132 and bus members outside the pole 12.

[0260] Furthermore, since the groove opening of the second groove 1311 is formed on the surface of the first conductive member 131 that is away from the second accommodating groove 12120, it is suggested that the second groove 1311 opens in the direction away from the active material application portion 21. As a result, a portion of the groove wall of the second groove 1311 of the first conductive member 131 is located between the second accommodating groove 12120 and the second conductive member 132, thereby separating the second accommodating groove 12120 and the second conductive member 132 and preventing contact between the electrolyte that has entered the second groove 1311 and the second conductive member 132, thereby reducing leakage of the electrolyte.

[0261] Of course, in other embodiments, the first cover plate 13 does not have to be a composite type made of multiple materials. For example, in other embodiments of the present application, Figure 28 is a schematic local cross-sectional view of a battery cell 10 provided according to some embodiments of the present application, and Figure 29 is an exploded structural view of the battery cell 10 shown in Figure 28. Referring to Figures 28 and 29, the entire first cover plate 13 can be installed in a non-composite type made of the same material, for example, to fit the positive pole, and the description thereof will be omitted here.

[0262] 25 to 27 again, in some embodiments, the first cover plate 13 is further fitted into the groove opening of the second accommodating groove 12120. In the above technical solution, fitting the first cover plate 13 into the second accommodating groove 12120 reduces the difficulty of assembling the first cover plate 13 and the pole 12, improves the assembly stability and connection reliability and convenience between the first cover plate 13 and the pole 12, and reduces the space occupied by the first cover plate 13 other than the pole 12. In addition, because the first cover plate 13 is fitted into the groove opening of the second accommodating groove 12120, the second accommodating groove 12120 has a relatively sufficient space for accommodating the conductive part 22.

[0263] Of course, in other embodiments of the present application, the method of fitting the first cover plate 13 and the pole 12 is not limited to being fitted into the second accommodating groove 12120, and the first cover plate 13 may also be directly fitted over the outside of the pole 12, that is, to facilitate fitting with the bus member of the battery 100, it may be directly fitted over the groove opening of the second accommodating groove 12120, and is not limited to this embodiment.

[0264] 25 to 27 , optionally, in the embodiment of the present application, at least a portion of the wall surface where the groove opening of the second accommodating groove 12120 of the terminal post 12 is formed is a guide slope 12126, which is used to guide the engagement between the first cover plate 13 and the groove opening of the second accommodating groove 12120. In the above technical solution, by processing the wall surface of the groove opening of the second accommodating groove 12120 into a slope having a guide function, it is possible to reduce the difficulty of assembling the first cover plate 13 and the second accommodating groove 12120 and improve the assembly efficiency of the first cover plate 13 and the second accommodating groove 12120. Furthermore, when the first cover plate 13 is welded to the guide slope 12126, the area of ​​the welded portion is increased, improving the reliability of the welded connection between the first cover plate 13 and the terminal post 12 and alleviating the problem of the collapse of the molten pool or the laser beam entering the terminal post 12 during welding.

[0265] 25 to 27, the second accommodating groove 12120 includes a first groove section 12124 and a second groove section 12125 located on the side of the first groove section 12124 that is closer to the pole outer end surface 123. Because the cross-sectional area of ​​the second groove section 12125 is larger than that of the first groove section 12124, the second accommodating groove 12120 has a stepped groove shape, and the connection between the first groove section 12124 and the second groove section 12125 forms a stepped surface 12127. Therefore, when the first cover plate 13 is fitted into the second accommodating groove 12120, it is fitted into the second groove section 12125 and supported by the stepped surface 12127.

[0266] In the above technical solution, by configuring the second accommodating groove 12120 in the form of a stepped groove, the first cover plate 13 can be stably fitted into the groove opening position of the second accommodating groove 12120, thereby improving the connection stability between the first cover plate 13 and the pole 12; and by limiting the groove depth of the first groove step 12124, a relatively sufficient space can be provided in the second accommodating groove 12120 to accommodate the conductive part 22.

[0267] Furthermore, when the wall surface where the groove mouth of the second accommodating groove 12120 of the pole post 12 is formed is the guide slope 12126, the cross-sectional area of ​​the second groove step 12125 is set to gradually increase along the direction approaching the pole post outer end surface 123, so that the side wall of the second groove step 12125 forms the guide slope 12126, thereby facilitating processing and satisfying the guide requirements simply and effectively.

[0268] 25 to 27 again, in the embodiments of the present application, the first cover plate 13 may further be provided with stress relief grooves 133 if necessary, and the stress relief grooves 133 are located in the outer circumferential region of the first cover plate 13 to help relieve stress on the first cover plate 13. In the above technical solution, the provision of the stress relief grooves 133 on the first cover plate 13 can relieve 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 poles 12, so as to alleviate problems such as deformation and damage caused by stress on the first cover plate 13.

[0269] Specifically, when the first cover plate 13 is fitted into the second receiving groove 12120 and welded, the stress relief groove 133 relieves stress generated during welding, improves lateral heat conduction, and reduces the likelihood of damage or deformation of the first cover plate 13. At the same time, if the first cover plate 13 is a composite type including the first conductive member 131 and the second conductive member 132, the stress relief groove 133 is installed in the first conductive member 131 and located at the outer circumferential region of the second conductive member 132. Therefore, when the first conductive member 131 is fitted into the second receiving groove 12120 and welded, the stress relief groove 133 relieves stress generated during welding, improves lateral heat conduction, and reduces the likelihood of damage or deformation of the second conductive member 132. In addition, when the second conductive member 132 and the first conductive member 131 are fitted and welded, the stress relief groove 133 releases the stress generated by the welding, improves the lateral conduction of heat, and reduces the probability of deformation of the first conductive member 131 or the first conductive member 131 being unable to be fitted into the second accommodating groove 12120.

[0270] Referring to Figures 28 to 29, in the embodiment of the present application, a second cover plate 14 may be further installed on the casing assembly 1 if necessary, and the second cover plate 14 is installed to cover the outside of the first through hole 12130 and at the same time is located outside the conductive portion 22 in the second accommodating groove 12120.

[0271] It should be noted that when the casing assembly 1 includes the second cover plate 14, the casing assembly 1 may also include the first cover plate 13, or may not also include the first cover plate 13. Furthermore, when the casing assembly 1 includes both the second cover plate 14 and the first cover plate 13, the first cover plate 13 may be a composite type using multiple types of materials, or a non-composite type using the same material.

[0272] In the above technical solution, at least a portion of the conductive portion 22 is located within the second accommodating groove 12120, and the second cover plate 14 covers that portion of the conductive portion 22, and the second cover plate 14 is further configured to cover the first through hole 12130. This alleviates the problem of the electrolyte in that portion overflowing from the pole 12 when the electrolyte enters the second accommodating groove 12120 through the first through hole 12130, thereby improving the reliability of the battery cell 10.

[0273] 28 and 29, 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 together the three components of the portion of the conductive portion 22, the second cover plate 14, and the second end wall 12121, in order to improve the reliability of the connection between the pole post 12 and the conductive portion 22. Furthermore, because the second cover plate 14 can press the conductive portion 22, the second cover plate 14 can improve the stability with which the conductive portion 22 is accommodated in the second accommodating groove 12120.

[0274] In the present embodiment, the electrode post 12 may be an integrally molded electrode post or a composite electrode post molded separately. Referring again to Figures 28 and 29, for example, the electrode post 12 may include a first electrode post portion 124 and a second electrode post portion 125 made of different materials and electrically connected to each other. The second electrode post portion 125 is located on the side of the first electrode post portion 124 away from the active material coated portion 21, and the receiving portion 121 is installed in the first electrode post portion 124, or the receiving portion 121 is installed in the first electrode post portion 124 and the second electrode post portion 125, and the conductive portion 22 is electrically connected to the first electrode post portion 124.

[0275] In the above technical solution, the pole 12 is arranged in a composite form by combining different materials, and the first pole part 124 located on the inside is used to fit and electrically connect with the conductive part 22, and the second pole part 125 located on the outside is used to electrically connect with the bus members, etc. This is advantageous for assembling and electrically connecting the pole 12 with related members, reduces mutual interference between the electrical connection position between the pole 12 and the conductive part 22 and the electrical connection position between the pole 12 and the bus members of the battery 100, and improves the reliability and stability of the battery cell 10.

[0276] For example, if the material of the conductive part 22 is different from the material of the bus member, the first electrode post part 124 can be installed so that it is made of the same material as the conductive part 22, and the second electrode post part 125 can be installed so that it is made of the same material as the bus member. This allows welding between the second electrode post part 125 and the bus member, and welding between the first electrode post part 124 and the conductive part 22, which is advantageous in improving the reliability and stability of the electrical connection between the conductive part 22 and the electrode post 12, and between the electrode post 12 and the bus member.

[0277] Furthermore, when the pole 12 is of the composite type as in the above embodiments and has the second receiving groove 12120 and the first through-hole 12130 as in any of the above embodiments, in some embodiments, the casing assembly 1 can also include the second cover plate 14 as in any of the above embodiments, in which case the second cover plate 14 and the first pole portion 124 can be made of the same material and can be electrically connected to the second cover plate 14, 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 can be connected by welding.

[0278] For example, referring to Figures 28 and 29, if the 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 bus member is an aluminum sheet, the second cover plate 14 can be installed on the copper material and the first cover plate 13 can be installed on the aluminum material. In this case, the second cover plate 14 and the first pole portion 124 may be made of the same material and effectively welded, the second pole portion 125 and the first cover plate 13 may be made of the same material and effectively welded, and the first cover plate 13 and the bus member may be made of the same material and effectively welded.

[0279] In the examples of the present application, when the accommodating portion 121 has a second accommodating groove 12120, the engagement between the battery core assembly 2 and the second accommodating groove 12120 is not limited depending on the configuration of the battery core assembly 2, and includes, for example, the following two examples of the third and fourth embodiments, but is not limited thereto.

[0280] FIG. 30 is a schematic local cross-sectional view of a battery cell 10 provided according to some embodiments of the present application. Referring to FIG. 30, in the third embodiment, when the accommodating portion 121 has a second accommodating groove 12120, at least a portion of the second converging portion 2213 is accommodated in the second accommodating groove 12120.

[0281] It should be noted that the specific configuration of the battery core assembly 2 in the third embodiment is basically the same as the specific configuration of the battery core assembly 2 in the above-mentioned Example 1, and the description of Example 1 can be referred to, so the description thereof will be omitted here. In this third embodiment, the tab portion 221 includes a second converging portion 2213 formed by gathering and connecting multiple tab sheets 2211. Therefore, at least a portion of the second converging portion 2213 can be relatively easily accommodated in the second accommodating groove 12120, facilitating the assembly of the conductive portion 22 and the electrode post 12.

[0282] In some optional examples, referring to FIG. 30 , the connection position between the first convergent portion 2212 and the second convergent portion 2213 can be located corresponding to the first through-hole 12130, that is, on a projection plane perpendicular to the first direction Z, the orthogonal projection of the connection position between the first convergent portion 2212 and the second convergent portion 2213 is located within the orthogonal projection range of the first through-hole 12130, so that the second convergent portion 2213 can easily extend to the first through-hole 12130 a relatively short distance and enter the second accommodating groove 12120, thereby reducing redundancy and saving costs.

[0283] It should be understood that the converging position of the tab sheet 2211 can be designed based on the position of the first through-hole 12130, for example, by adopting the above-mentioned symmetrical converging form or asymmetrical converging form, and the connection position between the first converging portion 2212 and the second converging portion 2213 can be set corresponding to the first through-hole 12130, but the description thereof will be omitted here. Also, as mentioned above, when the second converging portion 2213 forms a plate-like structure by ultrasonic tack welding, it is easy for the second converging portion 2213 to pass through the first through-hole 12130.

[0284] Referring to Figure 30, in this third embodiment, the accommodating portion 121, in addition to having the second accommodating groove 12120, may also have a third accommodating groove 12140 located on the side of the second accommodating groove 12120 that is close to the active material application portion 21, the surface of the pole 12 facing the active material application portion 21 is the pole inner end face 122, and the groove opening of the third accommodating groove 12140 is formed in the pole inner end face 122, and the third accommodating groove 12140 and the second accommodating groove 12120 are connected via the first through hole 12130, and in this case, at least a portion of the first converging portion 2212 may be accommodated in the third accommodating groove 12140.

[0285] In the above technical solution, at least a portion of the first converging portion 2212 of the tab portion 221 is accommodated in the third accommodating groove 12140, and at least a portion of the second converging portion 2213 is accommodated in the second accommodating groove 12120, thereby making better use of the space within the pole 12 to accommodate a larger-sized active material applied portion 21, further reducing the space occupied by the tab portion 221 within the casing 11, improving the energy density of the battery cell 10, and better reducing the redundancy of the tab portion 221 within the casing 11, further reducing the probability of a short circuit between the tab portion 221 and the active material applied portion 21, and further reducing the risk of the tab portion 221 being inserted backwards into the active material applied portion 21.

[0286] It should be noted that the specific shape of the third receiving groove 12140 is not limited and may be a regular or irregular shape, such as a cylindrical groove having a rectangular, elliptical, or racetrack-shaped cross section, a trapezoidal groove having a rectangular cross section with gradually varying cross-sectional dimensions, a hemispherical groove having a circular cross section with gradually varying cross-sectional dimensions, a semi-elliptical groove having an elliptical cross section with gradually varying cross-sectional dimensions, etc. In an embodiment of the present application, the third receiving groove 12140 may be configured with a cross-sectional shape in which the length is greater than the width, such as a rectangular, elliptical, or racetrack shape, which is advantageous for receiving the first converging portion 2212.

[0287] In the third embodiment, the second converging portion 2213 is electrically connected directly or indirectly to the electrode post 12. For example, when the second converging portion 2213 is directly electrically connected to the electrode post 12, for example, when the second converging portion 2213 is welded to the electrode post 12, the structure of the battery core assembly 2 can be simplified, the number of components can be reduced, the assembly process can be simplified, and assembly efficiency can be improved. Meanwhile, the method and position of the direct electrical connection between the second converging portion 2213 and the electrode post 12 are not limited. For example, the electrical connection position between the second converging portion 2213 and the pole 12 may be located on the second end wall 12121 and / or the second side wall 12123, and further, the electrical connection position between the second converging portion 2213 and the second end wall 12121 may extend along the length or width direction of the second end wall 12121, and further, the second end wall 12121 may have a second sunken groove 12122, and the electrical connection position between the second converging portion 2213 and the second end wall 12121 may be located within the second sunken groove 12122, etc. For corresponding technical effects, refer to the descriptions of the above embodiments, and the description thereof will be omitted here.

[0288] As an optional technical solution, an adapter sheet 222 may be installed on the conductive portion 22 as needed, in which case the second converging portion 2213 is indirectly electrically connected to the electrode post 12. Specifically, referring to FIG. 29 , when the conductive portion 22 includes the adapter sheet 222, the adapter sheet 222 is connected to the second converging portion 2213, and the conductive portion 22 is electrically connected to the electrode post 12 via the adapter sheet 222. In this case, at least a portion of the adapter sheet 222 is accommodated in the second accommodating groove 12120, and in this example, at least a portion of the second converging portion 2213 is also accommodated in the second accommodating groove 12120.

[0289] In the above technical solution, the active material coating portion 21 can be electrically connected to the electrode post 12 via the first converging portion 2212, the second converging portion 2213, and the adapter sheet 222, in that order, and the electrical connection position between the conductive portion 22 and the electrode post 12 is located on the adapter sheet 222. For example, the electrical connection can be achieved by welding (e.g., laser welding) the adapter sheet 222 to the electrode post 12. Furthermore, the adapter sheet 222 and the tab sheet 2211 are two separate members and are connected by a method such as welding (e.g., ultrasonic welding).

[0290] In the above technical solution, at least a portion of the second converging portion 2213 and at least a portion of the adapter sheet 222 are accommodated in the second accommodating groove 12120, thereby making better use of the space within the pole 12 and further reducing the space occupied by the conductive portion 22 within the casing 11, thereby further improving the volumetric energy density of the battery cell 10. In addition, installing the adapter sheet 222 with a sheet structure makes it easy for the adapter sheet 222 to pass through the first through-hole 12130 and extend into the second accommodating groove 12120.

[0291] Furthermore, by using the adapter sheet 222 to achieve an indirect electrical connection between the second converging portion 2213 and the electrode post 12, the adapter sheet 222 can be welded to the electrode post 12 using a portion that avoids the second converging portion 2213, which strengthens the weld between the adapter sheet 222 and the electrode post 12, reduces the risk of weld cracking, and further improves the reliability and stability of the battery cell 10. At the same time, by electrically connecting the electrode post 12 and the tab sheet 2211 via the adapter sheet 222, the structure of the tab sheet 2211 can also be simplified.

[0292] The method and location of the direct electrical connection between the adapter sheet 222 and the electrode post 12 are not limited. For example, the adapter sheet 222 and the electrode post 12 are electrically connected by welding. For example, the electrical connection position between the adapter sheet 222 and the electrode post 12 may be located on the second end wall 12121 and / or the second side wall 12123. The electrical connection position between the adapter sheet 222 and the second end wall 12121 may extend along the length or width direction of the second end wall 12121. Furthermore, the second end wall 12121 may have a second recessed groove 12122, and the electrical connection position between the adapter sheet 222 and the second end wall 12121 may be located within the second recessed groove 12122. For corresponding technical effects, refer to the descriptions of the above embodiments, and the description thereof will be omitted here. When the electrical connection position between the adapter sheet 222 and the pole 12 is located on the second end wall 12121 and / or the second side wall 12123, at least a portion of the adapter sheet 222 is accommodated in the second accommodating groove 12120, thereby simplifying the structure of the adapter sheet 222, reducing redundancy, and reducing costs.

[0293] Referring to Figure 11, in the fourth embodiment, the conductive portion 22 includes an adapter sheet 222 for electrically connecting the second converging portion 2213 and the pole 12, the accommodating portion 121 has a second accommodating groove 12120, and at least a portion of the adapter sheet 222 is accommodated in the second accommodating groove 12120 and electrically connected to the pole 12.

[0294] In the above technical solution, the fourth embodiment differs from the technical solution including the adapter sheet 222 of the third embodiment in that in the fourth embodiment, at least a portion of the adapter sheet 222 is accommodated in the second accommodating groove 12120, but the relative position of the tab portion 221 and the second accommodating groove 12120 is not limited, that is, at least a portion of the tab portion 221 can be accommodated in the second accommodating groove 12120, or the tab portion 221 can be located completely outside the second accommodating groove 12120, thereby meeting different structural design requirements.

[0295] In the above technical solution, by accommodating at least a portion of the adapter sheet 222 in the second accommodating groove 12120, the adapter sheet 222 can occupy space within the pole 12, thereby reducing the space occupied by the adapter sheet 222 within the casing 11 to accommodate a larger-sized active material application portion 21, improving the energy density of the battery cell 10, and reducing the probability of a short circuit between the adapter sheet 222 and the active material application portion 21, thereby reducing the risk of a short circuit in the battery core assembly 2, so as to improve the stability and reliability of the battery cell 10.

[0296] Furthermore, by using the adapter sheet 222 to achieve an indirect electrical connection between the second converging portion 2213 and the electrode post 12, the adapter sheet 222 can be welded to the electrode post 12 using a portion that avoids the second converging portion 2213, which strengthens the weld between the adapter sheet 222 and the electrode post 12, reduces the risk of weld cracking, and further improves the reliability and stability of the battery cell 10. At the same time, by electrically connecting the electrode post 12 and the tab sheet 2211 via the adapter sheet 222, the structure of the tab sheet 2211 can also be simplified.

[0297] FIG. 31 is a schematic cross-sectional view of a battery cell 10 according to some embodiments of the present application. Referring to FIG. 31, in some other embodiments of the present application, the accommodating portion 121 has a fourth accommodating groove 12150, which is a groove body having a groove-like structure with a certain depth, the surface of the pole 12 facing away from the active material coated portion 21 is the pole outer end surface 123, the groove opening of the fourth accommodating groove 12150 is formed on the pole outer end surface 123, the fourth accommodating groove 12150 is connected to the inside of the casing 11 through the second through hole 12160, and the conductive portion 22 does not have to be accommodated in the fourth accommodating groove 12150. For example, the conductive portion 22 may be drilled in the second through hole 12160, and the electrical connection position between the conductive portion 22 and the pole 12 is located on the hole wall of the second through hole 12160 formed in the pole 12.

[0298] In the above embodiment, the provision of the fourth accommodating groove 12150 facilitates 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 electrode post 12 can be utilized to seal the second through hole 12160. For example, welding the conductive portion 22 to the wall of the second through hole 12160 at the position where the second through hole 12160 and the fourth accommodating groove 12150 are connected can facilitate the operation. Furthermore, by controlling the welding marks, the second through hole 12160 can be sealed using the welding marks and the conductive portion 22, thereby alleviating the problem of electrolyte leakage from the casing 11 through the second through hole 12160.

[0299] It should be noted that the specific shape of the fourth receiving groove 12150 is not limited, and may be a regular or irregular shape, such as a cylindrical groove having a rectangular, elliptical, or racetrack cross section, a trapezoidal groove having a rectangular cross section with gradually varying cross-sectional dimensions, a hemispherical groove having a circular cross section with gradually varying cross-sectional dimensions, or a semi-elliptical groove having an elliptical cross section with gradually varying cross-sectional dimensions.

[0300] In the embodiment of the present application, the shape of the second through hole 12160 may be elongated to fit the sheet-like local shape of the conductive portion 22, which is advantageous for penetrating the sheet-like local portion of the conductive portion 22. At the same time, when the second through hole 12160 is elongated, the fourth accommodating groove 12150 may be configured with a shape in which the cross-sectional length is greater than the width, such as a rectangle, an oval, a racetrack, etc. In this case, the length direction of the second through hole 12160 can be aligned with the cross-sectional length direction of the fourth accommodating groove 12150, thereby making full use of space.

[0301] It should be noted that the receiving portion 121 in the embodiments of the present application does not necessarily have to have the above-mentioned at least one receiving groove. For example, in some other embodiments of the present application, Fig. 32 is a schematic local cross-sectional view of a battery cell 10 provided by some embodiments of the present application. Referring to Fig. 32, the receiving portion 121 may have only a third through hole 12170, the surface of the electrode post 12 facing the active material coated portion 21 is the electrode post inner end surface 122, and the surface of the electrode post 12 facing away from the active material coated portion 21 is the electrode post outer end surface 123. The third through hole 12170 is in the form of a through hole and penetrates the electrode post inner end surface 122 and the electrode post outer end surface 123, and at least a portion of the conductive portion 22 is drilled in the third through hole 12170. The electrical connection position between the conductive portion 22 and the electrode post 12 is not limited. For example, the electrical connection position may be located on the hole wall where the third through-hole 12170 of the electrode post 12 is formed, or the electrical connection position may be located on the outer end surface 123 of the electrode post outside the third through-hole 12170, so that the conductive portion 22 penetrates the third through-hole 12170. The shape of the third through-hole 12170 is not limited. It may be a hole with a regular shape with a uniform cross-section, or a hole with a variable cross-sectional shape with an unequal cross-section. The cross-sectional shape of the third through-hole 12170 is not limited. It may be an elongated shape such as a rectangle, ellipse, or racetrack to match the shape of the sheet-like local portion of the conductive portion 22. This is advantageous for the sheet-like local portion of the conductive portion 22 to be drilled into the third through-hole 12170, and a description thereof will be omitted here.

[0302] FIG. 33 is a schematic cross-sectional view of a battery cell 10 according to some embodiments of the present application, FIG. 34 is a schematic view of the engagement between a battery core assembly 2 and a support 3 according to some embodiments of the present application, and FIG. 35 is a cross-sectional view taken along line CC in FIG. 34. Referring to FIGS. 33 to 35, in the embodiment of the present application, the battery cell 10 further includes a support 3, which is located within the casing 11 and is located on the side of the active material coated portion 21 that is close to the pole 12, and which has an escape hole 31 for avoiding the conductive portion 22, and which can extend through the escape hole 31 to the side of the support 3 that is away from the active material coated portion 21 so as to be welded to the pole 12, thereby ensuring that the charging and discharging operations of the battery cell 10 are performed normally.

[0303] In the above technical solution, by providing the support 3 on the side of the active material-coated portion 21 closest to the pole 12, the support 3 can be used to separate the active material-coated portion 21 from the casing 11, improving the reliability of the battery cell 10. Furthermore, by providing the relief hole 31 in the support 3, the conductive portion 22 can be guided and restrained so that it passes through the relief hole 31 and fits into the pole 12. This eliminates the need for the conductive portion 22 to detour around the edge of the support 3 to get close to the pole 12. This not only simplifies the arrangement of the conductive portion 22, saves material for the conductive portion 22, and reduces costs, but also allows the support 3 to support and guide the fit between the conductive portion 22 and the pole 12, reducing the risk of a short circuit between the conductive portion 22 and the active material-coated portion 21 and further improving the reliability of the battery cell 10.

[0304] Referring again to Figures 33 to 35, the support 3 is optionally provided with a guide portion 32 that surrounds and forms at least a portion of the escape hole 31, and at least a portion of the guide portion 32 extends into the storage portion 121.

[0305] It should be noted that the guide portion 32 protrudes from the support 3 and extends into the accommodating portion 121, and at least a portion of the escape hole 31 is formed within the guide portion 32. This allows at least a portion of the conductive portion 22 to be easily accommodated within the accommodating portion 121 when the conductive portion 22 is drilled through the escape hole 31, thereby improving the assembly efficiency of the conductive portion 22. At the same time, the installation of the guide portion 32 makes the fit between the support 3 and the pole 12, and between the support 3 and the conductive portion 22, both tighter and more reliable, making the structure of the battery cell 10 more compact and further advantageous for improving the energy density of the battery cell 10.

[0306] 33 to 35 again, a third groove is optionally provided in the support 3, and at least a portion of the pole post 12 located in the casing 11 is housed in the third groove .

[0307] In the above technical solution, the third groove 38 is provided in the support 3, and at least a portion of the portion of the pole 12 located inside the casing 11 is accommodated in the third groove 38 of the support 3, thereby improving the compactness of the structure, which is advantageous in reducing the space occupied by the support 3 inside the casing 11, and in improving the volumetric energy density of the battery cell 10.

[0308] Furthermore, in some embodiments, the guide portion 32 can be involved in defining the third groove 38, which simplifies the structure of the support 3, reduces the difficulty of designing and processing the support 3, and is advantageous for increasing the thickness of the guide portion 32 and improving the guiding reliability of the conductive portion 32. It is also advantageous for improving the stability of the electrode post 12, thereby ensuring the reliability of the electrical connection between the electrode post 12 and the battery core assembly 2 and improving the reliability of the charging and discharging operations of the battery cell 10.

[0309] 33 to 35 , optionally, in the embodiment of the present application, the relief hole 31 includes a first hole section 311 and a second hole section 312, the second hole section 312 being located on the side of the first hole section 311 closer to the active material coating section 21, and the cross-sectional area of ​​the second hole section 312 gradually increasing in the direction away from the first hole section 311. At least a portion of the first converging section 2212 may be accommodated within the second hole section 312, and the second converging section 2213 may be drilled in the first hole section 311.

[0310] In the above technical solution, the escape hole 31 is configured to include a second hole section 312 that gradually widens toward the active material-coated portion 21, thereby making it easier for the second hole section 312 to accommodate more first converging portions 2212, improving the compactness of the fit between the support 3 and the battery core assembly 2, reducing the overall volume of the battery cells 10, allowing more battery cells 10 to be accommodated in the battery 100, and improving the volumetric energy density of the battery 100. Furthermore, in the above technical solution, the first converging portion 2212 and the second converging portion 2213 have been described in detail in the above embodiments, and therefore will not be described again here.

[0311] In the embodiments of the present application, the support 3 may have an integral structure or a separate structure. FIG. 36 is a structural schematic diagram of an integral support 3 provided in some embodiments of the present application. Referring to FIG. 36, when the support 3 has an integral structure, the relief hole 31 is formed as a through-hole penetrating the support 3. This makes the support 3 of an integral structure easy to process, relatively reliable, and facilitates assembly of the support 3 and the casing assembly 1, improving assembly efficiency and fitting stability. It should be understood that the processing method for the support 3 can be specifically selected depending on the material of the support 3. For example, when the support 3 is made of an insulating plastic material, the support 3 of an integral structure can be obtained by injection molding.

[0312] 37 is a structural schematic diagram of a separate support 3 provided according to some embodiments of the present application. Referring to FIG. 37, when the support 3 has a separate structure, the support 3 includes a removable first support 33 and a second support 34. The first support 33 and the second support 34 are both elongated plate-like structures and can be removably connected to each other; for example, they can be fitted together by insertion or engagement, facilitating assembly. Furthermore, the first support 33 has a semi-perforated structure on the side adjacent to the second support 34, and another semi-perforated structure with a matching shape is provided on the side adjacent to the first support 33. The semi-perforated structures of the first support 33 and the second support 34 together surround each other to form an annular relief hole 31. That is, the relief hole 31 is defined between the first support 33 and the second support 34.

[0313] In the above technical proposal, the escape hole 31 is defined by the fitting of the first support 33 and the second support 34, and when assembling the support 3 and the battery core assembly 2, there is no need to pass the conductive part 22 through the escape hole 31 from one end to the other. Instead, the first support 33 and the second support 34 can be combined at the position of the conductive part 22 to sandwich the conductive part 22, and the escape hole 31 surrounds the conductive part 22, which makes it easier to assemble the support 3 and the battery core assembly 2 and improves assembly efficiency.

[0314] As an alternative technical solution, when the cross section of the escape hole 31 is elongated, the first support 33 and the second support 34 are arranged on both sides of the width of the escape hole 31; for example, when the width of the escape hole 31 is horizontal, the first support 33 and the second support 34 are located on the left and right sides of the escape hole 31, thereby facilitating the engagement of the first support 33 and the second support 34 with the conductive part 22.

[0315] Figure 38 is a schematic cross-sectional view of a battery core assembly 2 and a support 3 provided in some embodiments of the present application, and Figure 39 is a structural exploded view of a battery core assembly 2, a support 3, and a casing assembly 1 provided in some embodiments of the present application. Refer to Figures 33, 38, and 39. In the embodiments of the present application, the configuration of the support 3 is not limited thereto. For example, a cased guide surface 35 may be further installed on the edge of the support 3. The cased guide surface 35 may be a sloped or curved surface. When projected orthogonally along the first direction Z, the orthogonal projections of the active material application portion 21 are all located within the orthogonal projection range of the support 3, and the orthogonal projection range of the support 3 exceeds the orthogonal projection range of the active material application portion 21. During assembly, the support 3 and the battery core assembly 2 can be preassembled, and then the preassembled assembly is attached to the casing 11. During attachment, the support 3 is located at the front end of the active material application portion 21, i.e., the support 3 enters the casing 11 before the active material application portion 21. This makes it easier for the support 3 to enter the casing 11 using the casing entry guide surface 35. Furthermore, the relatively large projected area of ​​the support 3 provides protection for the active material application portion 21, reducing the likelihood of scratches between the active material application portion 21 and the casing 11, improving assembly efficiency and success rate. Furthermore, the contact area between the support 3 and the active material application portion 21 can be increased, reducing stress concentration problems and eliminating the need for other structural components.

[0316] 38 , in the embodiment of the present application, the battery cell 10 further includes an inner insulating member 4, which is located inside the casing 11 and surrounds the outside of the active material-coated portion 21, and the inner insulating member 4 is connected to the support 3. In the above embodiment, on the one hand, surrounding the active material-coated portion 21 with the inner insulating member 4 improves the insulation reliability between the active material-coated portion 21 and the casing 11, reduces or prevents corrosion of the casing 11 due to contact between the active material-coated portion 21 and the casing 11, and reduces electrolyte leakage problems due to corrosion of the casing 11, thereby improving the reliability of the battery cell 10. On the other hand, connecting the inner insulating member 4 to the support 3 reduces the difficulty of fixing the inner insulating member 4, improving the reliability of the inner insulating member 4 surrounding the outside of the active material-coated portion 21.

[0317] 38 , in this embodiment, the support 3 includes a main body 36 and an extension 37. The main body 36 is located on the side of the active material-coated portion 21 closest to the pole 12, and the extension 37 is connected to the main body 36 and located in the outer circumferential region of the active material-coated portion 21. For example, the extension 37 may 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 may extend from a local portion of the circumferential direction of the main body 36 to form a block structure protruding from the main body 36. The provision of the extension 37 restricts the position of the active material-coated portion 21 and alleviates the problem of corrosion caused by toner falling off the edge of the active material-coated portion 21 overlapping the casing 11. The provision of the extension 37 also fixes the inner insulating member 4, improving the connection reliability between the inner insulating member 4 and the support 3 and providing relatively good insulation.

[0318] For example, referring to Figure 38, the main body portion 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 application portion 21, and the end of the inner insulating member 4 is fitted into the positioning groove 39, preventing the inner insulating member 4 from protruding from the edge of the main body portion 36. This allows the main body portion 36 to protect the inner insulating member 4 when it is inserted into the casing, and reduces the probability of scratches between the inner insulating member 4 and the casing 11.

[0319] Specifically, referring to Figure 39, the inner insulating member 4 may be an integrated film, having main body portions 41 located on both sides of the active material application portion 21 in the thickness direction, and connecting portions 42 connecting the two main body portions 41, the connecting portions 42 being located on the side of the active material application portion 21 away from the pole 12, and the edge of the main body portion 41 on the side away from the connecting portions 42 extending to and connected to the extension portions 37, thereby providing relatively good insulating performance and facilitating connection.

[0320] In the embodiment of the present application, the specific method for attaching the pole 12 to the casing 11 is not limited, and may be, for example, riveting or welding, which will be described below.

[0321] For example, in some embodiments, Figure 40 is an exploded view of the structure of the electrode post 12, casing 11, and seal pad provided by some embodiments of the present application, Figure 41 is an assembly view of the first electrode post 12, casing 11, and seal pad shown in Figure 40, and Figure 42 is a schematic view of the structure of the electrode post 12 provided by some embodiments of the present application. Referring to Figures 40 to 42, the electrode post 12 may have an integral structure and be riveted to the casing 11, which can improve the assembly efficiency of the electrode post 12 and reduce the height of the electrode post 12 protruding from the surface of the casing 11, which is advantageous for improving energy density and improving compactness.

[0322] Specifically, referring to Figures 40 to 42, the pole post 12 may include a stopper portion 1281 and a perforation portion 1282 before being riveted, and when assembling, the stopper portion 1281 stops inside the casing 11, the perforation portion 1282 is perforated in the mounting hole 113, and then the portion of the perforation portion 1282 located outside the casing 11 is riveted to form a flange portion 1283, and the flange portion 1283 is stopped outside the casing 11, thereby realizing the mounting of the pole post 12.

[0323] 40 and 41, the casing assembly 1 may optionally include a number of seal pads, such as a first seal pad 191 and a second seal pad 192 shown in Fig. 40, fitted between the casing 11 and the terminal post 12. Before riveting, the seal pads are assembled in place, and after riveting the terminal post 12, the terminal post 12 presses the seal pads to form a seal, thereby using the seal pads to improve the sealing of the fitting point between the terminal post 12 and the casing 11. The number, position and material of the seal pads are not limited, and for example, the material may be silicon, plastic, etc., and is not limited here.

[0324] 41, the length c of the flange portion 1283 may be 1 mm or more and the thickness d may be 2 mm or more to improve the rivet joint strength of the terminal post 12. If 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 terminal post 12 and the casing 11 will be reduced under relatively strong vibration.

[0325] 43 is an assembly diagram of the pole 12, the casing 11, and the seal pad provided by some embodiments of the present application, and FIG. 44 is an exploded view of the pole 12 shown in FIG. 43. Referring to FIGS. 43 and 44, the pole 12 may have a separate structure and be welded to be attached to the casing 11. For example, the pole 12 includes a first portion 1291 and a second portion 1292, and at least a portion of the first portion 1291 is attached to the outside of the casing 11, and at least a portion of the second portion 1292 is attached to the inside of the casing 11. The pole 12 can be attached by drilling at least one of the first portion 1291 and the second portion 1292 into the attachment hole 113 and welding (for example, laser welding) the other portion to the attachment of the pole 12.

[0326] In some alternative embodiments, FIG. 45 is an orthographic view of a battery cell 10 provided according to some embodiments of the present application, and FIG. 46 is an orthographic view of a battery cell 10 provided according to some embodiments of the present application. Referring to FIG. 45 and FIG. 46, there are multiple poles 12, and they are all located on the same surface of the casing 11, which makes installation easier and improves assembly efficiency.

[0327] It should be noted that the arrangement method of the multiple poles 12 on the surface on the same side is not limited, and for example, when the cross section of the poles 12 has an elongated structure, for example, when the cross section length is three times or more the cross section width, such as an oval, racetrack or rectangular shape, it is relatively well adapted to the thin, flat casing 11. For example, the multiple poles 12 are all provided on one surface (referred to as the first wall surface 110) in the height direction of the casing 11, the length direction of each pole 12 coincides with the length direction of the first wall surface 110 of the casing 11, and the multiple poles 12 are spaced apart along the length direction and / or width direction of the first wall surface 110.

[0328] For example, in the example shown in FIG. 45 , when the first wall surface 110 has two poles 12, the two poles 12 are spaced apart along the length direction of the first wall surface 110. Alternatively, referring to FIG. 45 , the portion of the pole 12 located outside the casing 11 (referred to as the pole exterior) is annular, and in the length direction of the first wall surface 110, the length a1 of the inner ring of the pole exterior is equal to or greater than one-third of the length a0 of the first wall surface 110, and in the width direction of the first wall surface 110, the width b1 of the inner ring of the pole exterior is equal to or greater than three-quarters of the width b0 of the first wall surface 110. This advantageously provides a relatively large area for the pole 12 to electrically connect to the bus member, thereby facilitating further improvement of the current-passing capacity of the pole 12. Exemplarily, the length a1 of the inner ring of the pole exterior is equal to or greater than 50 mm, and the width b1 of the inner ring of the pole exterior is equal to or greater than 30 mm.

[0329] 45, when the first wall 110 has two poles 12 and the two poles 12 are spaced apart along the length of the first wall 110, in some alternative embodiments, the poles 12 include a portion located within the casing 11 (referred to as the pole interior), and the length of the pole interior along the length of the first wall 110 is at least one-third of the length of the first wall 110, and the width of the pole interior along the width of the first wall 110 is at least three-quarters of the width of the first wall 110. This advantageously provides a relatively large area for the poles 12 to electrically connect to the conductive portion 22, further improving the current-passing capacity of the poles 12. For example, the length of the pole interior is at least 50 mm, and the width of the pole interior is at least 30 mm.

[0330] 46, when the first wall surface 110 has four poles 12, two of the poles 12 are spaced apart along the width direction of the first wall surface 110 to form one set, and a total of two sets are spaced apart along the length direction of the first wall surface 110. Optionally, referring to FIG. 46, the portion of the poles 12 located outside the casing 11 (referred to as the "outside poles") is annular, and in the length direction of the first wall surface 110, the length a2 of the inner ring of the outside poles is equal to or greater than one-third of the length a0 of the first wall surface 110, and in the width direction of the first wall surface 110, the width b2 of the inner ring of the outside poles is equal to or greater than three-fifths of the width b0 of the first wall surface 110. This advantageously provides a relatively large area for the poles 12 to be electrically connected to the bus members, thereby facilitating further improvement of the current-passing capacity of the poles 12. Illustratively, the length a2 of the inner ring outside the pole is 50 mm or more, and the width b2 of the inner ring outside the pole is 8 mm or more.

[0331] 46 , when the first wall surface 110 has four poles 12, two of the poles 12 are spaced apart along the width direction of the first wall surface 110 to form one set, and the two sets are spaced apart along the length direction of the first wall surface 110, in some alternative embodiments, the poles 12 include a portion located within the casing 11 (referred to as the pole interior), and the length of the pole interior along the length direction of the first wall surface 110 is at least one-third of the length of the first wall surface 110, and the width of the pole interior along the width direction of the first wall surface 110 is at least one-fifth of the width of the first wall surface 110. This advantageously provides a relatively large area for the poles 12 to electrically connect to the conductive portion 22, facilitating further improvement of the current passing capacity of the poles 12. For example, the length of the pole interior is at least 50 mm, and the width of the pole interior is at least 8 mm.

[0332] 45 and 46 , in some embodiments, a portion of the electrode post 12 is located inside the casing 11 and a portion of the electrode post 12 is located outside the casing 11, and the orthogonal projection area of ​​the portion of the electrode post 12 located outside the casing 11 on the first wall surface 110 is 5% or more of the area of ​​the first wall surface 110, for example, 5%, 6%, 7%, 8%, 9%, 10% or more of the area of ​​the first wall surface 110. This is advantageous for increasing the connection area between the electrode post 12 and the bus member, increasing the effective current passage area between the electrode post 12 and the bus member, and improving the charging speed of the battery cell 10.

[0333] Also, in some embodiments, Figure 47 is a cross-sectional view taken along line DD in Figure 46. Referring to Figure 47, in order to easily improve the volumetric energy density of the battery cell 10, the vertical height t1 from the portion of the pole 12 protruding from the outer surface of the first wall surface 110 (referred to as the pole exterior) to the first wall surface 110 may be 3.2 mm or less, and the vertical height t2 from the portion of the pole 12 protruding from the inner surface of the first wall surface 110 (referred to as the pole interior) to the first wall surface 110 may be 2 mm or less.

[0334] Fig. 48 is a schematic cross-sectional view of a casing assembly 1 provided according to some embodiments of the present application, Fig. 49 is a schematic cross-sectional view of the casing assembly 1 provided according to some embodiments of the present application, Fig. 50 is an orthographic view of a battery cell 10 provided according to some embodiments of the present application, Fig. 51 is a cross-sectional view taken along line EE in Fig. 50, and Fig. 52 is a schematic local cross-sectional view of a battery cell 10 provided according to some embodiments of the present application. Referring again to Figs. 48 to 52, in the embodiment of the present application, the casing 11 specifically includes a casing body 111 and a casing cover 112, the casing body 111 has a rectangular ring structure with one or both ends open, and when one end is open, there is one casing cover 112 which is provided to cover the open position, and when both ends are open, there are two casing covers 112 which are provided to cover the open ends of the casing body 111, respectively.

[0335] In detail, when the casing 11 includes a casing body 111 and a casing cover 112 and one end of the casing body 111 is open, the casing body 111 may be a one-piece molded product, specifically an elongated rectangular structure. In this case, the pole 12 may be provided on at least one of the casing body 111 and the casing cover 112. For example, referring to FIG. 48 , the pole 12 may be provided on one end of the casing body 111 that is remote from the casing cover 112. When the battery cell 10 is used in a vibration environment, the amplitude of the connection between the casing body 111 and the casing cover 112 is relatively small, and the connection between the casing body 111 and the casing cover 112 is not likely to crack. This improves the reliability of the battery cell 10 and also allows the casing body 111 to be made thinner, thereby reducing costs, weight, and the size of the battery cell 10.

[0336] Referring again to FIG. 48 as an optional technical solution, when there are multiple poles 12, all of the poles 12 are provided at one end of the casing body 111 that is remote from the casing cover 112. As a result, when the battery cell 10 is used in a vibration environment, the amplitude of the connection between the casing body 111 and the casing cover 112 is relatively small, and the connection between the casing body 111 and the casing cover 112 is less likely to crack, thereby improving the reliability of the battery cell 10. Furthermore, the thickness e1 of the end wall of the casing body 111 at the end that is remote from the casing cover 112 can be reduced to 2 mm or less, and the thickness e2 of the side wall connecting the end wall of the casing body 111 to the casing cover 112 can be reduced to 0.8 mm or less, thereby reducing costs, weight, and enabling the battery cell 10 to be made more compact.

[0337] When the first accommodating groove 12110, which is installed in correspondence with the mounting hole 113, is formed in the pole 12, the thickness of the portion of the pole 12 located on the side of the first accommodating groove 12110 away from the active material application portion 21 becomes relatively thin, thereby making it possible to weld the conductive portion 22 and the pole 12 from outside the casing 11. Referring to FIG. 48, when the casing 11 includes a casing main body 111 and a casing cover 112, and the casing cover 112 is provided at the open end of the casing main body 111, even if the pole 12 is provided at the sealed end of the casing main body 111, there is no need to worry about the problem of it being difficult to weld the conductive portion 22 and the pole 12 from inside the casing 11. Since the conductive portion 22 and the pole 12 can be welded from outside the casing 11, by providing the pole 12 at the sealed end of the casing main body 111, the connection stability and reliability between the casing main body 111 and the casing cover 112 can be improved.

[0338] When the second accommodating groove 12120 is formed in the pole 12, welding of the conductive part 22 and the pole 12 can be achieved from outside the casing 11 through the groove opening of the second accommodating groove 12120. Therefore, referring to FIG. 48, when the casing 11 includes a casing body 111 and a casing cover 112, and the casing cover 112 is provided at the open end of the casing body 111, even if the pole 12 is provided at the sealed end of the casing body 111, there is no need to worry about the problem of it being difficult to weld the conductive part 22 and the pole 12 from inside the casing 11. Since the conductive part 22 and the pole 12 can be welded from outside the casing 11, providing the pole 12 at the sealed end of the casing body 111 can improve the connection stability and reliability between the casing body 111 and the casing cover 112.

[0339] 49, in other embodiments of the present application, all of the poles 12 can be provided on the casing cover 112 as needed. This facilitates assembly of the poles 12 and the casing cover 112, and is not limited to this embodiment.

[0340] 50 to 52, in the embodiment of the present application, when there are a plurality of poles 12, the poles 12 may be disposed on two surfaces on different sides of the casing 11. For example, there may be a plurality of poles 12 disposed on adjacent surfaces of the casing 11, or there may be a plurality of poles 12 disposed on opposing surfaces of the casing 11.

[0341] When poles 12 are provided on both opposing surfaces of casing 11, the active material coated portion 21 can extend from the conductive portion 22 at positions adjacent to the poles 12 on each side, and the conductive portion 22 can fit and connect to the poles 12 on the adjacent side, thereby alleviating the problem of the tab portion 221 being pulled by the pole 12 on the same side and causing the connection between the tab portion 221 and the active material coated portion 21 to crack, thereby improving the reliability of the battery cell 10. It should be noted that the poles 12 on both sides may be the same or different, and the connection method between the poles 12 on both sides and the conductive portions 22 may be the same or different, and is not limited here.

[0342] Of course, in other embodiments of the present application, the electrode posts 12 may also be located on the surface of the side of the casing 11 that has the largest area. For example, in some optional embodiments of the present application, the electrode posts 12 may be located on the top surface of the casing 11. For example, in some optional embodiments of the present application, the electrode posts 12 may be located on the bottom surface of the casing 11. When the electrode posts 12 are located on the bottom surface of the casing 11, the receiving portion 121 can be used to receive the electrolyte, thereby improving the cycle life of the battery cell 10. When the electrode posts 12 are located on the bottom surface of the casing 11 and the support 3 is located at the bottom of the active material-coated portion 21, the contact area between the support 3 and the active material-coated portion 21 can be increased, thereby alleviating stress concentration problems and eliminating the need for other supporting structural members.

[0343] 53 is a structural schematic diagram of a casing cover 112 provided according to some embodiments of the present application, and FIG. 54 is a schematic diagram of a battery cell provided according to some embodiments of the present application. Referring to FIG. 53 and FIG. 54, in the embodiment of the present application, the casing 11 has a pressure release portion 16. The specific configuration of the pressure release portion 16 is not limited, and may be, for example, an explosion-proof valve or a fragile portion, etc., which is used to release pressure when the pressure inside the battery cell 10 is relatively high, thereby improving the reliability of the battery cell 10.

[0344] Alternatively, as shown in Fig. 54, the pressure relief portion 16 and the electrode post 12 may be located on the same surface of the casing 11, which facilitates processing and assembly. Alternatively, as shown in Figs. 48 and 53, the pressure relief portion 16 and the electrode post 12 may be located on opposite surfaces of the casing 11, which can save space, increase the volume of the electrode post 12, and reduce the adverse effect of the pressure relief portion 16 on the electrode post 12 when releasing pressure.

[0345] 48 and 53, in the present embodiment, the pressure relief portion 16 can be provided on the casing cover 112, if necessary. The casing cover 112 does not need to mount the electrode posts 12, and the connection between the casing cover 112 and the casing 11 is less susceptible to vibrations during the charging and discharging of the battery cells 10 and is less likely to crack. Therefore, the thickness of the casing cover 112 can be relatively thin, which further simplifies the processing and manufacturing of the pressure relief portion 16. For example, to fully improve the manufacturability of the battery cells 10, the casing cover 112 can be directly formed with integrally molded notches to easily form the pressure relief portion 16. It should be noted that in this embodiment, the electrode posts 12 can be provided on either the casing body 111 or the casing cover 112, and this is not limiting. For example, the pressure relief portion 16 can be integrally molded with the casing cover 112, which simplifies processing, simplifies assembly, improves production efficiency, and reduces costs.

[0346] 3 to 6, 20, and 24 to 25, a battery cell 10 according to a specific embodiment of the present invention will be described.

[0347] In the embodiment of the present application, the battery cell 10 has a rectangular parallelepiped shape, the height direction of the battery cell 10 is a first direction Z, the length direction of the battery cell 10 is a second direction X, and the thickness direction of the battery cell 10 is a third direction Y. The battery cell 10 includes a casing 11, which includes a casing body 111 and a casing cover 112. The casing body 111 has a rectangular ring structure, one end of the casing body 111 along the first direction Z is open and the other end along the first direction Z is closed, and the casing cover 112 is installed to cover the open position of the casing body 111.

[0348] At the same time, two poles are provided at the sealed end of the casing body 111 along the first direction Z, and the two poles are spaced apart along the second direction X, and are respectively a positive pole and a negative pole. Each of the two poles is a pole 12 with an accommodating portion 121, and the accommodating portion 121 has a second accommodating groove 12120. Specifically, the pole 12 includes a second end wall 12121 and a second side wall 12123. The second end wall 12121 is located on the side of the second side wall 12123 that is close to the casing cover 112, and the second end wall 12121 and the second side wall 12123 surround The second end wall 12121 has a first through hole 12130 formed therein, and the first through hole 12130 is located in a position close to the second side wall 12123 of the second end wall 12121. The surface of the pole 12 facing away from the casing cover 112 is the pole outer end face 123. The second end wall 12121 has a first through hole 12130 formed therein, and the first through hole 12130 is located in a position close to the second side wall 12123 of the second end wall 12121.

[0349] The battery cell 10 also includes a battery core assembly 2, which includes an active material application portion 21 and a tab portion 221, the active material application portion 21 being housed in the casing 11, the battery core assembly 2 including the active material application portion 21 and a conductive portion 22, the conductive portion 22 being electrically connected to the active material application portion 21 and the pole 12, the conductive portion 22 including a plurality of tab sheets 2211 extending from the active material application portion 21 along the first direction Z, one ends of the plurality of tab sheets 2211 close to the active material application portion 21 converging to form a first converging portion 2212, one ends of the plurality of tab sheets 2211 away from the active material application portion 21 converging and connected to form a second converging portion 2213, and the first converging portion 2212 connects the second converging portion 2213 to the active material application portion 21.

[0350] The second converging portion 2213 extends through the first through-hole 12130 into the second accommodating groove 12120 and is welded to the second end wall 12121 so as to electrically connect the active material coated portion 21 and the electrode post 12 via the tab portion 221. An orthogonal projection P2 of the second converging portion 2213 onto the electrode post 12 along the first direction Z is entirely located within the outer contour range S of the electrode post 12, and at least a portion of an orthogonal projection P3 of the first converging portion 2212 onto the electrode post 12 along the first direction Z is located within the outer contour range S of the electrode post 12.

[0351] Furthermore, the first cover plate 13 is fitted into the opening of the second accommodating groove 12120, so that after welding the tab portion 221 to the second end wall 12121 is completed, the opening of the second accommodating groove 12120 can be sealed by utilizing the fit between the first cover plate 13 and the pole 12. The first cover plate 13 is welded to the pole 12 to form an electrical connection. Thereafter, if a bus member is used to electrically connect the battery cells 10, the bus member may be welded to the first cover plate 13 to establish electrical connection with the pole 12.

[0352] In the above technical solution, on the one hand, by installing the second accommodating groove 12120 in the pole 12, the weight of the pole 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, because the groove opening of the second accommodating groove 12120 is formed in the pole outer end surface 123, and the pole outer end surface 123 is the surface of the pole 12 facing away from the active material applied portion 21, the second accommodating groove 12120 can be opened toward the side away from the active material applied portion 21. In this way, when at least a portion of the tab portion 221 is accommodated in the second accommodating groove 12120, it is possible to easily accommodate and organize the tab portion 221 through the groove opening of the second accommodating groove 12120, and it is also possible to easily perform a welding operation between the tab portion 221 and the pole 12 through the groove opening of the second accommodating groove 12120, which in turn reduces the difficulty of producing the battery cell 10 and improves the production efficiency of the battery cell 10.

[0353] Furthermore, the orthogonal projection P2 of the second converging portion 2213 on the electrode post 12 along the first direction Z may all be located within the outer contour range S of the electrode post 12. By welding the tab portion 221 to the electrode post 12 from the outside of the casing 11, the distance between the second converging portion 2213 and the electrode post 12 is relatively short, which realizes welding between the conductive portion 22 and the electrode post 12 and is advantageous to improving the welding reliability between the conductive portion 22 and the electrode post 12, shortening the overall length of the conductive portion 22, reducing the cost of the conductive portion 22, and improving the problem of reverse insertion due to the redundancy of the conductive portion 22, and improving the reliability of the battery cell 10. This is advantageous for improving reliability, and such an arrangement can further concentrate the space occupied by the conductive portion 22 and the electrode post 12 in the direction perpendicular to the first direction Z. By reducing the overall space occupied by both, other space in the battery cell 10 in the direction perpendicular to the first direction Z can be freed up, allowing other structures to be laid out, such as an insulating structure that can further improve the reliability of the battery cell 10 or accommodate more electrolyte to ensure the cycle life of the battery cell 10.

[0354] Furthermore, by welding the tab portion 221 and the pole 12 from outside the casing 11, the pole 12 may be provided at the sealed end of the casing body 111. In this way, when the battery cell 10 is used in a vibration environment, the amplitude of the connection between the casing body 111 and the casing cover 112 is relatively small, and cracks are less likely to occur at the connection between the casing body 111 and the casing cover 112. This improves the reliability of the battery cell 10 and is advantageous for reducing the thickness of the casing body 111, thereby reducing costs, reducing weight, and achieving a more compact battery cell 10.

[0355] At the same time, since the second accommodating groove 12120 can pass through the first through-hole 12130 and communicate with the inside of the casing 11, the second accommodating groove 12120 can be used as a buffering and temporary storage structure for the electrolyte. The casing 11 can accommodate more electrolyte. Since the electrolyte is consumed during the charging and discharging process of the battery cell 10, the more electrolyte there is, the longer the service life of the battery cell 10 can be. Furthermore, since the second accommodating groove 12120 can pass through the first through-hole 12130 and communicate with the inside of the casing 11, the second accommodating groove 12120 can also be used as a buffering structure for the gas generated inside the battery core assembly 2, which can reduce the expansion of the battery cell 10 and improve the reliability and stability of the battery cell 10.

[0356] According to some embodiments of the present application, the present application further provides a battery 100 including the battery cell 10 of any one of the above embodiments.

[0357] In the above technical solution, the battery cell 10 is installed in the battery 100, and the ends of the tab sheets 2211 that are away from the active material-coated portion 21 of the battery cell 10 are converged and connected to form a second convergent portion 2213. At least a portion of the orthogonal projection of the end of the second convergent portion 2213 connected to the first convergent portion 2212 on the pole along the first direction Z is located within the outer contour range S of the pole 12. This is advantageous in that it shortens the distance from the end 2214 of the conductive portion 22 to the pole 12 in the direction perpendicular to the first direction Z, thereby allowing the second convergent portion 2213 and the pole 12 to be relatively close to each other, thereby ensuring the reliability of the welding between the conductive portion 22 and the pole 12 and thus facilitating direct or indirect welding between the tab sheet 2211 and the pole 12, and thus ensuring the reliability of the battery cell 10 and the battery 100. On the other hand, such an arrangement is advantageous in that it shortens the overall length of the conductive portion 22, which not only reduces the cost of the conductive portion 22 but also alleviates the problem of reverse insertion due to the redundancy of the conductive portion 22, thereby further improving the reliability of the battery cell 10 and the battery 100. Furthermore, such an arrangement further concentrates the space occupied by the conductive portion 22 and the electrode post 12 in the direction perpendicular to the first direction Z. By reducing the overall space occupied by both, other space in the battery cell 10 in the direction perpendicular to the first direction Z is freed up, allowing other structures to be laid out, such as an insulating structure that can accommodate more electrolyte to further improve the reliability of the battery cell 10 or ensure the cycle life of the battery cell 10 and the battery 100.

[0358] According to some embodiments of the present application, the present application further provides an electric device 1000 including the battery 100 of the above embodiments, wherein the battery 100 is used to supply electric energy to the electric device 1000.

[0359] In the above technical solution, the battery 100 is installed in the electric device 1000, so that the reliability of the battery 100 can be improved, and therefore the reliability of the electric device 1000 can be improved.

[0360] It should be noted that, unless there is a contradiction, the embodiments and features of the embodiments of the present application can be combined with each other.

[0361] The above is merely a preferred embodiment of the present application and does not limit the present application, and various modifications and variations of the present application may be made by those skilled in the art. Any modifications, equivalent replacements, improvements, etc. made within the scope of the spirit and principles of the present application are also included in the scope of the claims of the present application.

Claims

1. A battery cell (10), a casing assembly (1) including a casing (11) and a pole (12) installed in the casing (11); a battery core assembly (2) including an active material applied portion (21) and a conductive portion (22) that electrically connects the active material applied portion (21) and the electrode post (12), wherein the conductive portion (22) includes a plurality of tab sheets (2211) extending from the active material applied portion (21) along a first direction (Z), one ends of the plurality of tab sheets (2211) that are close to the active material applied portion (21) converge to form a first converging portion (2212), one ends of the plurality of tab sheets (2211) that are away from the active material applied portion (21) converge and connect to form a second converging portion (2213), and the first converging portion (2212) connects the second converging portion (2213) and the active material applied portion (21), wherein an orthogonal projection (P1) of the end (2214) where the second convergent portion (2213) is connected to the first convergent portion (2212) on the polar pillar (12) along the first direction (Z) is at least partially located within an outer contour range (S) of the polar pillar (12); Battery cell (10).

2. 2. The battery cell (10) of claim 1, wherein orthogonal projections (P1) of the end (2214) on the pole (12) along the first direction (Z) are all located within an outer contour range (S) of the pole (12).

3. 3. The battery cell (10) according to claim 1 or 2, wherein orthogonal projections (P2) of the second converging portion (2213) on the pole (12) along the first direction (Z) are all located within an outer contour range (S) of the pole (12).

4. The battery cell (10) according to any one of claims 1 to 3, wherein an orthogonal projection (P3) of the first converging portion (2212) on the pole (12) along the first direction (Z) is at least partially located within an outer contour range (S) of the pole (12).

5. The battery cell (10) according to any one of claims 1 to 4, wherein the conductive portions (22) are plural, and at least a portion of the orthogonal projection (P1) of the end (2214) of each of the conductive portions (22) on the pole (12) along the first direction (Z) is located within an outer contour range (S) of the pole (12).

6. The battery cell (10) according to any one of claims 1 to 5, wherein an orthogonal projection (P1) of the end (2214) on the pole (12) along the first direction (Z) is disposed eccentrically with respect to the pole (12).

7. The battery cell (10) of any one of claims 1 to 6, wherein the conductive portion (22) further includes an adapter sheet (222), which is used to connect the second converging portion (2213) and the pole (12), and an orthogonal projection (P4) of the adapter sheet (222) on the pole (12) along the first direction (Z) is at least partially located within an outer contour range (S) of the pole (12).

8. The battery cell (10) according to any one of claims 1 to 6, wherein a housing portion (121) is provided in the pole (12), and at least a portion of the conductive portion (22) is housed within the housing portion (121).

9. At least a portion of the second converging portion (2213) is accommodated within the accommodation portion (121); and / or the conductive portion (22) further includes an adapter sheet (222), the adapter sheet (222) is used to connect the second converging portion (2213) and the pole (12), and at least a portion of the adapter sheet (222) is accommodated in the accommodation portion (121); The battery cell (10) of claim 8.

10. The battery cell (10) according to claim 9, wherein at least a portion of the first converging portion (2213) is housed within the housing portion (121).

11. A battery cell (10) as described in claim 8, wherein the accommodating portion (121) has a first accommodating groove (12110), the surface of the pole (12) facing the active material application portion (21) is the pole inner end face (122), the groove opening of the first accommodating groove (12110) is formed in the pole inner end face (122), and at least a portion of the conductive portion (22) is accommodated within the first accommodating groove (12110).

12. 12. The battery cell (10) of claim 11, wherein the casing (11) has a mounting hole (113), the pole (12) is mounted in the mounting hole (113), and the depth (H1) of the first accommodating groove (12110) along the first direction (Z) is equal to or greater than the minimum distance (H2) from the pole inner end face (122) to the mounting hole (113).

13. A battery cell (10) as described in claim 11 or 12, wherein the electrode post (12) includes a first end wall (12111) and a first side wall (12113), the first end wall (12111) is located on the side of the first side wall (12113) away from the active material application portion (21), the first end wall (12111) and the first side wall (12113) surround each other to form the first accommodating groove (12110), and the electrical connection position between the conductive portion (22) and the electrode post (12) is located on the first end wall (12111) and / or the first side wall (12113).

14. A battery cell (10) as described in claim 13, wherein the first end wall (12111) has a first recessed groove (12112), and at least a portion of the electrical connection position between the conductive portion (22) and the first end wall (12111) is located within the first recessed groove (12112).

15. The battery cell (10) according to any one of claims 11 to 14, wherein the electrode post (12) has a first groove (126), the surface of the electrode post (12) away from the active material application portion (21) is an electrode post outer end face (123), and the groove opening of the first groove (126) is formed in the electrode post outer end face (123).

16. 16. The battery cell (10) according to claim 15, wherein the casing assembly (1) further includes a groove cover (7), the groove cover (7) being attached to the pole (12) and sealingly capping the groove opening of the first recessed groove (126).

17. The battery cell (10) according to any one of claims 11 to 16, wherein at least a portion of the second converging portion (2213) is accommodated within the first accommodating groove (12110).

18. The battery cell (10) of claim 17, wherein at least a portion of the first converging portion (2212) is accommodated within the first accommodating groove (12110).

19. A battery cell (10) as described in any one of claims 11 to 18, wherein the conductive portion (22) further includes an adapter sheet (222), which is used to connect the second converging portion (2213) and the pole (12), and at least a portion of the adapter sheet (222) is accommodated within the first accommodating groove (12110).

20. A battery cell (10) as described in claim 8, wherein the accommodating portion (121) has a second accommodating groove (12120), the surface of the pole (12) facing away from the active material application portion (21) is the pole outer end face (123), the groove opening of the second accommodating groove (12120) is formed in the pole outer end face (123), the second accommodating groove (12120) is connected to the inside of the casing (11) via a first through hole (12130), and the conductive portion (22) is drilled in the first through hole (12130) and at least a portion of it is accommodated in the second accommodating groove (12120).

21. A battery cell (10) as described in claim 20, wherein the electrical connection position between the conductive portion (22) and the pole (12) is located on the hole wall of the first through hole (12130) formed in the pole (12).

22. A battery cell (10) as described in claim 20, wherein the electrode post (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) closest to the active material application portion (21), the second end wall (12121) and the second side wall (12123) surround each other to form the second accommodating groove (12120), the first through hole (12130) is opened in the second end wall (12121), and the electrical connection position between the conductive portion (22) and the electrode post (12) is located in the second end wall (12121) and / or the second side wall (12123).

23. A battery cell (10) as described in claim 22, wherein the second end wall (12121) has a second recessed groove (12122), and at least a portion of the electrical connection position between the conductive portion (22) and the second end wall (12121) is located within the second recessed groove (12122).

24. The battery cell (10) according to any one of claims 20 to 23, wherein the casing (11) has a mounting hole (113), the pole (12) is mounted in the mounting hole (113), and the depth (H3) of the second accommodating groove (12120) along the first direction (Z) is equal to or greater than the minimum distance (H4) from the pole outer end face (123) to the mounting hole (113).

25. The battery cell (10) of any one of claims 20 to 24, wherein the casing assembly (1) further includes a first cover plate (13), which is fitted to the terminal post (12) and seals the groove opening of the second accommodating groove (12120), and the first cover plate (13) is electrically connected to the terminal post (12).

26. 26. The battery cell (10) of claim 25, wherein 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) being fitted to and electrically connected to the pole (12), and the second conductive member (132) being fitted to and electrically connected to the first conductive member (131).

27. A battery cell (10) as described in claim 26, wherein the first conductive member (131) has a second groove (1311), the second conductive member (132) is fitted into the second groove (1311), and the groove opening of the second groove (1311) is formed on the surface of the first conductive member (131) facing away from the second accommodating groove (12120) so that the second conductive member (132) is exposed from the groove opening of the second groove (1311).

28. The battery cell (10) according to any one of claims 25 to 27, wherein the first cover plate (13) is fitted into the groove opening of the second receiving groove (12120).

29. A battery cell (10) as described in claim 28, wherein the wall surface on which the groove opening of the second accommodating groove (12120) of the pole post (12) is formed is a guide inclined surface (12126), and the guide inclined surface (12126) is used to guide the engagement of the first cover plate (13) with the groove opening of the second accommodating groove (12120).

30. The battery cell (10) of claim 28 or 29, wherein the second accommodating groove (12120) includes a first groove step (12124) and a second groove step (12125) located on the side of the first groove step (12124) closest to the pole outer end surface (123), the cross-sectional area of ​​the second groove step (12125) being larger than the cross-sectional area of ​​the first groove step (12124) so ​​as to form a stepped surface (12127) between the first groove step (12124) and the second groove step (12125), and the first cover plate (13) is fitted into the second groove step (12125) and supported on the stepped surface (12127).

31. The battery cell (10) according to any one of claims 25 to 30, wherein the first cover plate (13) has a stress relief groove (133), and the stress relief groove (133) is located in an outer peripheral region of the first cover plate (13).

32. The casing assembly (1) further includes a second cover plate (14), which is provided to cover the outside of the first through hole (12130) and the conductive portion (22) located in the second accommodating groove (12120), and the battery cell (10) described in any one of claims 20 to 31.

33. The battery cell (10) according to any one of claims 20 to 32, wherein at least a portion of the second converging portion (2213) is accommodated within the second accommodating groove (12120).

34. A battery cell (10) as described in claim 33, wherein the accommodating portion (121) further has a third accommodating groove (12140), the surface of the pole (12) facing the active material application 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) closest to the active material application portion (21), and the groove opening of the third accommodating groove (12140) is formed in the pole inner end face (122), the third accommodating groove (12140) and the second accommodating groove (12120) are connected via the first through hole (12130), and at least a portion of the first converging portion (2212) is accommodated within the third accommodating groove (12140).

35. A battery cell (10) as described in any one of claims 20 to 34, wherein the conductive portion (22) further includes an adapter sheet (222), which is used to connect the second converging portion (2213) and the pole (12), and at least a portion of the adapter sheet (222) is accommodated within the second accommodating groove (12120).

36. 9. A battery cell (10) as described in claim 8, wherein the accommodating portion (121) has a fourth accommodating groove (12150), the surface of the electrode post (12) away from the active material coating portion (21) is the electrode post outer end surface (123), the groove opening of the fourth accommodating groove (12150) is formed in the electrode post outer end surface (123), the fourth accommodating groove (12150) is connected to the inside of the casing (11) via the second through hole (12160), the conductive portion (22) is drilled in the second through hole (12160), and the electrical connection position between the conductive portion (22) and the electrode post (12) is located on the hole wall of the second through hole (12160) formed in the electrode post (12).

37. The battery cell (10) according to any one of claims 8 to 36, wherein the pole (12) includes 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 coated portion (21), the accommodating portion (121) is installed on the first pole portion (124) or on the first pole portion (124) and the second pole portion (125), and the conductive portion (22) is electrically connected to the first pole portion (124).

38. The battery further includes a support (3) located within the casing (11) and on a side of the active material application portion (21) that is close to the pole (12), the support (3) having an escape hole (31) for avoiding the conductive portion (22), and the conductive portion (22) is adapted to extend through the escape hole (31) to a side of the support (3) that is away from the active material application portion (21). A battery cell (10) according to any one of claims 1 to 37.

39. The battery further includes a support (3) located within the casing (11) and on a side of the active material application portion (21) that is close to the pole (12), the support (3) having an escape hole (31) for avoiding the conductive portion (22), the conductive portion (22) adapted to extend through the escape hole (31) to a side of the support (3) that is away from the active material application portion (21), the support (3) being provided with a guide portion (32) that surrounds and forms at least a part of the escape hole (31), and at least a part of the guide portion (32) extending into the storage portion (121). A battery cell (10) according to any one of claims 8 to 37.

40. The battery cell (10) according to claim 38 or 39, wherein the support (3) is provided with a third groove (38), and at least a portion of the pole (12) located within the casing (11) is accommodated within the third groove (38).

41. The battery cell (10) according to any one of claims 38 to 40, wherein the relief hole (31) includes a first hole section (311) and a second hole section (312), the second hole section (312) is located on a side of the first hole section (311) that is closer to the active material application section (21), and the cross-sectional area of ​​the second hole section (312) gradually increases in a direction away from the first hole section (311), at least a portion of the first converging section (2212) is accommodated within the second hole section (312), and the second converging section (2213) is drilled in the first hole section (311).

42. The battery cell (10) according to any one of claims 38 to 41, wherein the support (3) is of an integral structure, or the support (3) is of a separate and removable structure and includes a first support (33) and a second support (34), and the relief hole (31) is defined between the first support (33) and the second support (34).

43. The battery further includes an inner insulating member (4) located within the casing (11), surrounding the outside of the active material application portion (21), and connected to the support (3). A battery cell (10) according to any one of claims 38 to 42.

44. The battery cell (10) according to any one of claims 1 to 43, wherein the casing (11) has a pressure release portion (16), and the pressure release portion (16) and the electrode post (12) are located on the same surface of the casing (11), or the pressure release portion (16) and the electrode post (12) are respectively located on two surfaces on different sides of the casing (11).

45. The battery cell (10) according to any one of claims 1 to 43, wherein the casing (11) has a pressure release section (16), the casing (11) includes a casing body (111) and a casing cover (112), one end of the casing body (111) is open, the casing cover (112) is provided at the open end of the casing body (111), and the pressure release section (16) is provided at the casing cover (112).

46. A battery (100) comprising a battery cell (10) according to any one of claims 1 to 45.

47. 47. An electrical device (1000) comprising the battery (100) of claim 46.

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