Battery cell, battery, electrical device, and method for assembling a battery cell

Abstract

The present invention relates to a battery cell, a battery, an electrical device, and a method for assembling a battery cell, wherein the battery cell includes a casing assembly including a casing and a first pole post, and a battery core assembly including an active material coated portion and a conductive portion, wherein the casing includes a casing body having an opening in which the first pole post is installed, and a casing cover covering the opening, the active material coated portion is housed within the casing body, and the conductive portion is electrically connected to the active material coated portion and the first pole post. The present invention can reduce the probability of cracking at the welded joint between the casing body and the casing cover during the battery manufacturing process, thereby improving the reliability of the battery cell.

Description

[Technical Field]

[0001] This application relates to the battery technology field, and more particularly to battery cells, batteries, electrical devices, and methods for assembling battery cells. [Overview of the Initiative] [Means for solving the problem]

[0002] The embodiments of this application provide a battery cell, a battery, an electrical device, and a method for assembling a battery cell, which are advantageous in improving the reliability of the battery cell.

[0003] In a first aspect, an embodiment of the present application provides a battery cell comprising: a casing assembly comprising a casing and a first pole column, wherein the casing comprises a casing body and a casing cover, the casing body having an opening, the casing cover covering the opening, and the first pole column being installed in the casing body; and a battery core assembly comprising an active material coating portion and a conductive portion, wherein the active material coating portion is housed within the casing body, and the conductive portion is electrically connected to the active material coating portion and the first pole column.

[0004] In the above proposed technology, since the first poles of any adjacent battery cells are connected to each other, when the battery vibrates or deforms, the first poles between any adjacent battery cells pull on each other. At this time, since the first poles are installed in the casing body, the force acting on the first poles does not act directly on the casing cover but is preferentially transmitted to the casing body. This extends the distance over which the force is transmitted to the welded joint between the casing body and the casing cover. At the same time, the casing body preferentially deforms when subjected to force, reducing the force received by the welded joint between the casing body and the casing cover. This effectively reduces the probability of cracking at the welded joint between the casing body and the casing cover during battery use, thereby improving the reliability of the battery cells.

[0005] In some embodiments, a housing is provided on the first pole column, and at least a portion of the conductive part is housed within the housing.

[0006] In the above proposed technology, by installing a housing section on the first pole column, the weight of the first pole column can be reduced to some extent, thereby improving the gravimetric energy density of the battery cell and the battery. At the same time, by housing at least a portion of the conductive part within the housing section, the space occupied by the conductive part within the first pole column is reduced, and the space occupied by the conductive part within the casing can be reduced. If the dimensions of the casing are constant, space can be saved to accommodate a larger active material coating section within the casing, thereby improving the volumetric energy density of the battery cell. Simultaneously, by housing at least a portion of the conductive part within the housing section, the space occupied by the battery cell itself is reduced, allowing more battery cells to be housed in the same volume of battery, thereby further improving the volumetric energy density of the battery. In addition, by housing at least a portion of the conductive part within the housing, the redundancy of the conductive part within the casing can be reduced to some extent, the probability of short circuits between the conductive part and the active material coated part can be reduced, and the probability of short circuits in the battery core assembly can be reduced, thereby improving the operational reliability and stability of the battery cell and the battery. Furthermore, housing at least a portion of the conductive part in the housing of the first pole column facilitates the connection between the conductive part and the first pole column.

[0007] In some embodiments, the housing portion has a first housing groove, the surface of the first pole column facing the active material coated portion is the inner end face of the pole column, the groove opening of the first housing groove is formed on the inner end face of the pole column, and at least a portion of the conductive portion is housed in the first housing groove.

[0008] In the above proposed technology, by providing a first housing groove in the first pole column, the weight of the first pole column can be reduced to some extent, thereby improving the gravimetric energy density of the battery cell and battery. At the same time, since the opening of the first housing groove is formed on the inner end face of the pole column, and the inner end face of the pole column is the surface on the side of the first pole column that is close to the active material coated area, the first housing groove is open toward the direction of the active material coated area, thereby facilitating the extension of the conductive part into the first housing groove and improving assembly efficiency. Simultaneously, because the first housing groove faces the active material coated area, the first housing groove also functions as a buffer and temporary storage structure for the electrolyte, allowing more electrolyte to be contained within the casing. As the electrolyte is consumed during the charging and discharging process of the battery cell, a larger amount of electrolyte can extend the service life of the battery cell. Furthermore, since the first housing groove faces the active material coating area, the first housing groove also functions as a gas containment and buffer structure for gases generated inside the battery core assembly, reducing the expansion of the battery cell and improving the reliability and stability of the battery cell. Moreover, since the first housing groove is located inside the electrode post, external foreign matter and impurities are less likely to enter the first housing groove, reducing the impact of external foreign matter and impurities on the battery core assembly, ensuring the stability and reliability of the operation of the battery core assembly, further improving the stability and reliability of the battery cell and battery. Additionally, since the first housing groove is located inside the electrode post and at least a portion of the conductive part is housed in the first housing groove, it is easier to restrict the position of the conductive part from inside the electrode post, facilitating connection between the conductive part and the first electrode post.

[0009] In some embodiments, the casing has mounting holes, the first pole post is mounted in the mounting holes, and along the axial direction of the first pole post, the depth H1 of the first housing groove is greater than or equal to the minimum distance H2 from the inner end face of the pole post to the mounting hole.

[0010] In the above proposed technology, in the axial direction of the first pole column, the depth of the first housing groove is greater than or equal to the minimum distance from the inner end face of the pole column to the mounting hole. This allows for full utilization of the volume of the first pole column, which is advantageous for providing a relatively large depth to the first housing groove and accommodating more conductive parts. Furthermore, it significantly reduces the space occupied by conductive parts within the casing, further improving the energy density of the battery cell and further reducing the redundancy of conductive parts within the casing. At the same time, because the first housing groove has a relatively large depth, it can also accommodate gases generated by the battery core assembly, ensuring the reliability and stability of the battery cell, allowing for the accommodation of more electrolyte, and thus guaranteeing the service life of the battery cell.

[0011] In some embodiments, the housing includes a first end wall and a first side wall, the first end wall being located on the side of the first side wall away from the active material coated portion, the first end wall and the first side wall surrounding each other to form a first housing groove, and the electrical connection position between the conductive portion and the first pole column is located on the first end wall and / or the first side wall.

[0012] In the above proposed technology, by locating the position where the conductive part is electrically connected to the first pole column at at least one of the first end wall and the first side wall, the first housing groove not only serves to accommodate at least a portion of the conductive part, but also to realize an electrical connection with the conductive part. This simplifies the structure of the first pole column, facilitates the processing of the first pole column, simplifies the structure of the conductive part, reduces the redundancy of the conductive part, and lowers the cost of the conductive part. Furthermore, by realizing an electrical connection with the conductive part using the groove wall of the first housing groove, the electrical connection area between the conductive part and the first pole column can be made relatively large, reducing the difficulty of electrical connection, improving the reliability and stability of the electrical connection, and further improving the performance of the battery cell. When the electrical connection position between the conductive part and the first pole column is located at the first end wall, it facilitates connecting the conductive part and the first end wall from the outside.

[0013] In some embodiments, the first end wall has a first recessed groove, and at least a portion of the electrical connection points between the conductive portion and the first end wall are located within the first recessed groove.

[0014] In the above proposed technology, by installing a first recessed groove in the first end wall, pre-positioning of the conductive part can be achieved using the first recessed groove, which is advantageous for accurately aligning the position and achieving electrical connection, thereby improving production efficiency. Furthermore, by installing a first recessed groove in the first end wall, the local thickness of the first end wall can be partially reduced, which is advantageous not only for facilitating electrical connection by welding but also for reducing the weight of the first pole column and improving the gravimetric energy density of the battery cell.

[0015] In some embodiments, the first pole column has a first groove, the surface of the first pole column away from the active material coated portion is the outer end surface of the pole column, and the groove opening of the first groove is formed on the outer end surface of the pole column.

[0016] In the above proposed technology, by installing a first groove on the first pole column, the weight of the first pole column can be further reduced, improving the gravimetric energy density of the battery cells and the battery. Meanwhile, the first groove is located on the outside of the first pole column, and structural components electrically connected to each battery cell in the battery can be housed or attached using the first groove, making full use of the space inside the first pole column and improving the space utilization rate and volumetric energy density of the battery. Furthermore, since the first pole column has both a first housing groove and a first recessed groove, and the active material coating portion is located on the side away from the first housing groove, and the first recessed groove is open in the direction away from the first housing groove, it is advantageous to electrically connect the conductive part and the groove wall of the first housing groove from the outside of the first pole column via the first recessed groove. For example, it becomes easy to weld the first pole column and the conductive part externally via the first recessed groove, which simplifies the processing and manufacturing of the battery cell and reduces processing and manufacturing costs.

[0017] In some embodiments, the casing assembly further includes a groove cover provided on the first pole and sealing the groove opening of the first concave groove.

[0018] In the above technical solution, by installing the groove cover, the electrical connection between adjacent battery cells in the battery can be facilitated, and the position of the electrical connection between the battery cells is such that the electrical connection position between the conductive part and the first pole is separated through the first concave groove, with less interference between the two, and the stability and reliability of the battery cells can be further improved. At the same time, the groove cover can prevent foreign objects from entering the first concave groove, reduce the interference of external foreign objects on the battery core assembly, and further improve the reliability and stability of the battery cells.

[0019] In some embodiments, the accommodating part has a second accommodating groove, the surface of the first pole on the side away from the active material coating part is the outer end face of the pole, the groove opening of the second accommodating groove is formed on the outer end face of the pole, the second accommodating groove communicates with the inside of the casing through the first through hole, the conductive part is drilled through the first through hole, and at least a part of it is accommodated in the second accommodating groove.

[0020] In the above technical solution, by providing a second receiving groove in the first pole, the weight of the first pole can be reduced to a certain extent, while improving the weight energy density of the battery cell and the battery. At the same time, the groove opening of the second receiving groove is formed on the outer end surface of the pole, and the outer end surface of the pole is the surface on the side away from the active material coating portion of the first pole. Thus, the second receiving groove is opened in a direction away from the active material coating portion. In this way, when at least a part of the conductive part is received in the second receiving groove, the accommodation and arrangement of the conductive part can be easily realized through the groove opening of the second receiving groove, or operations such as electrical connection between the conductive part and the first pole can be performed, further reducing the manufacturing difficulty of the battery cell and improving the production efficiency of the battery cell. At the same time, since the second receiving groove can communicate with the casing through the first through hole, the second receiving groove also functions as a buffer and temporary storage structure for the electrolyte, allowing more electrolyte to be stored in the casing. Because the electrolyte is consumed during the charge and discharge process of the battery cell, when there is more electrolyte, the service life of the battery cell can be extended. And since the second receiving groove can communicate with the casing through the first through hole, the second receiving groove also functions as a structure for receiving and buffering the gas generated inside the battery core assembly, reducing the expansion of the battery cell and improving the reliability and stability of the battery cell.

[0021] In some embodiments, the electrical connection position between the conductive part and the first pole is located on the hole wall of the first through hole where the receiving part is formed.

[0022] In the above technical solution, when the electrical connection position between the conductive part and the first pole is provided on the hole wall of the first through hole, the operation of electrical connection between the conductive part and the first pole can be performed through the second receiving groove. At the same time, the electrical connection position between the conductive part and the first pole can be sealed with respect to the first through hole, saving the sealing cost and reducing the leakage of the electrolyte.

[0023] In some embodiments, the housing includes a second end wall and a second side wall, the second end wall being located on the side of the second side wall adjacent to the active material coated portion, the second end wall and the second side wall surrounding each other to form a second housing groove, a first through hole being provided in the second end wall, and the electrical connection position between the conductive portion and the first pole column being located in the second end wall and / or the second side wall.

[0024] In the above proposed technology, by locating the electrical connection point between the conductive part and the first pole column in at least one of the second end wall and the second side wall, the second housing groove not only serves to accommodate at least a portion of the conductive part, but the groove wall of the second housing groove further serves to achieve an electrical connection with the conductive part. This simplifies the structure of the first pole column and facilitates the processing of the first pole column. Furthermore, since the first through hole is opened in the second end wall, it facilitates the extension of the conductive part into the second housing groove through the first through hole, simplifying the structure of the conductive part, reducing the redundancy of the conductive part, and lowering the cost of the conductive part. Furthermore, the opening direction of the groove opening of the second housing groove facilitates the electrical connection operation between the conductive part and the groove wall of the second housing groove via the groove opening of the second housing groove, reducing the difficulty of electrical connection. Moreover, by utilizing the groove wall of the second housing groove to achieve electrical connection with the conductive part, the electrical connection area between the conductive part and the first pole column can be relatively enlarged, improving the reliability and stability of the electrical connection and further enhancing the performance of the battery cell.

[0025] In some embodiments, the second end wall has a second recessed groove, and at least a portion of the electrical connection point between the conductive portion and the second end wall is located within the second recessed groove.

[0026] In the above proposed technology, by installing a second recessed groove in the second end wall, pre-positioning of the conductive part can be achieved using the second recessed groove, allowing for precise positioning and electrical connection, thereby improving production efficiency.

[0027] In some embodiments, the casing has mounting holes, the first pole post is mounted in the mounting holes, and the depth H3 of the second housing groove is greater than or equal to the minimum distance H4 from the outer end face of the pole post to the mounting hole, along the axial direction of the first pole post.

[0028] In the above proposed technology, in the axial direction of the first pole column, the depth of the second housing groove is greater than or equal to the minimum distance from the outer end face of the pole column to the mounting hole. This allows for full utilization of the volume of the first pole column, which is advantageous for providing a relatively large depth to the second housing groove and accommodating more conductive parts. Furthermore, it significantly reduces the space occupied by conductive parts within the casing, further improving the energy density of the battery cell and reducing the redundancy of conductive parts within the casing. At the same time, because the second housing groove has a relatively large depth, it can also accommodate gases generated by the battery core assembly, improving the reliability and stability of the battery cell, and allowing for the accommodation of more electrolyte, thereby extending the service life of the battery cell.

[0029] In some embodiments, the casing assembly further includes a first cover plate which fits with the first pole post and seals the opening of the second housing groove, and the first cover plate is electrically connected to the first pole post.

[0030] In the above proposed technology, by installing a first cover plate and sealing the groove opening of the second housing groove, leakage of the electrolyte inside the casing from the groove opening of the second housing groove can be prevented. Furthermore, since the first cover plate seals the groove opening of the second housing groove and is electrically connected to the first pole, an indirect electrical connection between the first pole and the bus member of the battery can be easily realized using the first cover plate, and this is advantageous in increasing the connection area of ​​the electrical connection point and further reducing the resistance of the electrical connection point.

[0031] 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 a first pole, and the second conductive member being fitted to and electrically connected to the first conductive member.

[0032] In the above proposed technology, the first cover plate is installed in a composite form, and the first conductive member is installed in the same material as the first pole post, thereby facilitating electrical connection between the first conductive member and the first pole post. Furthermore, because the second conductive member and the first conductive member are made of different materials, the second conductive member is used to facilitate electrical connection with the battery bus member, which is made of a different material than the first pole post.

[0033] 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 the surface of the first conductive member away from the second housing groove such that the second conductive member is exposed from the groove opening of the second groove.

[0034] In the above proposed technology, by fitting the second conductive member into the first conductive member, the difficulty of assembling the first and second conductive members can be reduced, and the stability and convenience of fitting the first and second conductive members can be improved. Furthermore, the thickness of the first cover plate can be reduced, decreasing 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 away from the second housing groove through the groove opening of the second recess, which is advantageous for achieving electrical connection between the second conductive member and the battery bus members other than the first pole posts. In addition, since the groove opening of the second recess is formed on the surface of the first conductive member away from the second housing groove, the first conductive member can be isolated between the second housing groove and the second conductive member, thereby preventing contact between the electrolyte in the second recess and the second conductive member and reducing electrolyte leakage.

[0035] In some embodiments, the first cover plate is fitted into the groove of the second housing groove.

[0036] In the above proposed technology, by fitting the first cover plate into the second housing groove, the difficulty of assembling the first cover plate and the first pole post can be reduced, the assembly stability and connection reliability and convenience of the first cover plate and the first pole post can be improved, and the space occupied by the first cover plate other than the first pole post can be reduced. In addition, since the first cover plate is fitted into the groove opening of the second housing groove, there can be a relatively sufficient space within the second housing groove for housing the conductive part.

[0037] In some embodiments, the wall surface on which the groove opening of the second housing groove of the first pole column is formed is a guide slope, which is used to guide the fitting of the first cover plate with the groove opening of the second housing groove.

[0038] In the above proposed technology, by processing the wall surface of the groove opening of the second storage groove into a slope that has a guiding function, the difficulty of assembling the first cover plate and the second storage groove can be reduced, and the assembly efficiency of the first cover plate and the second storage groove can be improved.

[0039] In some embodiments, the second accommodating groove includes the first groove step and the second groove step on the side adjacent to the pole column outer end face of the first groove step, and the cross-sectional area of ​​the second groove step is 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 on the stepped surface.

[0040] In the above proposed technology, by setting the second housing groove in the shape of a stepped groove, the first cover plate can be stably fitted into the groove opening position of the second housing groove, thereby improving the connection stability between the first cover plate and the first pole column. Furthermore, by limiting the groove depth of the first groove step, a relatively sufficient space for housing the conductive part can be provided within the second housing groove.

[0041] In some embodiments, the first pole includes a first pole portion and a second pole portion made of different materials and electrically connected, the second pole portion is located on the side of the first pole portion away from the active material coated portion, the housing portion is installed on the first pole portion or on the first pole portion and the second pole portion, and the conductive portion is electrically connected to the first pole portion.

[0042] In the above proposed technology, by installing the first pole column in a composite form combining different materials, the housing fit and electrical connection between the first pole column and the conductive part located on the inside is utilized, and the electrical connection between the second pole part located on the outside and the bus components of the battery is utilized. This is advantageous for realizing the assembly and electrical connection of the first pole column and related components, reduces mutual interference between the electrical connection position between the pole column and the conductive part and the electrical connection position between the pole column and the bus components of the battery, and improves the reliability and stability of the battery cell.

[0043] In some embodiments, the housing has a fourth housing groove, the surface of the first pole away from the active material coating is the outer end face of the pole, the groove opening of the fourth housing groove is formed on the outer end face of the pole, the fourth housing groove communicates with the inside of the casing through a second through hole, the conductive part is drilled in the second through hole, and the electrical connection position between the conductive part and the first pole is located at the hole wall of the second through hole in which the housing is formed.

[0044] In the above proposed technology, by installing a fourth accommodating groove, electrical connection between the conductive part and the hole wall of the second through-hole can be easily achieved. Furthermore, in some cases, the electrical connection between the conductive part and the first pole column can be used to seal the second through-hole.

[0045] In some embodiments, the battery cell further includes a support located within the casing and on the side adjacent to the first pole column of the active material coating, and the support has a relief hole to avoid the conductive portion, the conductive portion extending through the relief hole toward the side of the support away from the active material coating.

[0046] In the above proposed technology, by installing a fourth accommodating groove, electrical connection between the conductive part and the hole wall of the second through-hole can be easily achieved. Furthermore, in some cases, the electrical connection between the conductive part and the first pole column can be used to seal the second through-hole.

[0047] In some embodiments, the support is provided with a guide portion, which surrounds at least a portion of the escape hole, and at least a portion of the guide portion extends into the housing portion.

[0048] In the above proposed technology, the support has a guide portion that extends at least part within the housing portion and is formed to surround at least part of the relief hole via the guide portion. As a result, at least part of the conductive portion is easily housed within the housing portion, improving the assembly efficiency of the conductive portion. At the same time, the installation of the guide portion makes the fitting between the support and the pole column, and between the support and the conductive portion, tighter and more reliable, resulting in a more compact battery cell structure, which is further advantageous for improving the energy density of the battery cell.

[0049] In some embodiments, the opposite edge of the support casing cover has a casing-in guide surface including an arcuate surface and / or an inclined surface. In the above technical invention, the casing-in guide surface can act as a guide, allowing the support to be smoothly assembled into the casing body, and the active material coating area enters the casing only after the support has entered the casing, reducing the problem of the casing damaging the active material coating area.

[0050] In some embodiments, the support is a single integrated structure, or the support is a separate structure including a removable first support and a second support, with the relief hole defined between the first support and the second support.

[0051] In the above technical proposal, if the support is an integrated structure, the support is easy to process, has relatively good reliability, and the assembly of the support and casing assembly is easy, improving assembly efficiency and mating stability. If the support is a separate structure, the relief hole is defined by the mating of the first support and the second support, and when assembling the support and the battery core assembly, it is not necessary to pass the conductive part from one end of the relief hole to the other. 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 relief hole surrounds the conductive part, making the assembly of the support and the battery core assembly easier and improving assembly efficiency.

[0052] In some embodiments, the battery cell further includes an inner insulating member, which is located within the casing and encloses the outside of the active material coated area, and is connected to a support.

[0053] In the above proposed technology, by enclosing the active material coated portion with an inner insulating member, the insulation reliability between the active material coated portion and the casing is improved, corrosion of the casing due to contact between the active material coated 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. At the same time, by connecting the inner insulating member to a support, the difficulty of fixing the inner insulating member is reduced, and the reliability of the inner insulating member enclosing the outside of the active material coated portion can be improved.

[0054] In some embodiments, the casing assembly includes at least one first pole post that is riveted to the casing body.

[0055] In the above proposed technology, since the first pole column is connected to the casing body by riveting, making the casing body thinner makes welding difficult, and riveting the first pole column to the casing body is relatively easy. In other words, connecting the first pole column and the casing body by riveting is easy to install and operate, and riveting the first pole column to the casing body is advantageous for thinning and lightening the casing body, thereby reducing the weight of the battery cell. When the dimensions of the battery cell are constant, riveting the first pole column makes it easy to thin the casing body, which is also advantageous for increasing the internal space of the casing body, thereby improving the energy density of the battery cell.

[0056] In some embodiments, the casing body is provided with mounting holes, and the first pole column includes an integrally molded pole column body, a first position limiting base and a second position limiting base, the pole column body is drilled in the mounting holes, and the first and second position limiting bases are installed at both ends of the pole column body along the axial direction of the mounting holes so as to rivet the first pole column to the casing body, the first position limiting base is fitted to the outside of the casing body in a position-limiting manner, and the second position limiting base is fitted to the inside of the casing body in a position-limiting manner.

[0057] In the above proposed technology, the first and second position limiting bases each extend radially outward from the peripheral wall of the mounting hole along the radial direction of the mounting hole, the first position limiting base can restrict the movement of the first pole column relative to the casing body in the direction toward the inside of the casing body, and the second position limiting base can restrict the movement of the first pole column relative to the casing body in the direction toward the outside of the casing body, thereby facilitating secure mounting of the first pole column to the mounting hole via the first and second position limiting bases, which is advantageous for riveting the first pole column to the casing body, facilitating assembly of the first pole column to the casing body, and the space between the first pole column and the casing body is This design facilitates a secure connection between the first pole and the casing body without requiring other connection methods, which is advantageous in simplifying the structure of the casing assembly and streamlining the assembly process. At the same time, the pole body of the first pole, the first position limiting base, and the second position limiting base are integrally molded, saving parts and costs. Furthermore, it ensures the strength of the first pole, making it less likely to separate from the casing due to vibration or external pulling during the charging and discharging process of the battery cell after it has been fitted into the casing, and less likely to crack or break due to vibration or external pulling, thereby improving the stability and reliability of the battery cell.

[0058] In some embodiments, the dimension of the first pole column in a first direction is greater than the dimension of the first pole column in a second direction, the first and second directions are perpendicular, and both the first and second directions are perpendicular to the axial direction of the mounting hole.

[0059] In the above proposed technology, the orthographic projection shape of the first pole column may be non-circular in the plane comprising the first and second directions. This is advantageous for ensuring that the first pole column and the wall on which the first pole column is installed in the casing body coincide well in the first and second directions. It is also advantageous for increasing the cross-sectional area of ​​the first pole column that can be placed on the wall of the casing body, for increasing the current-passing area of ​​the first pole column within the limited placement area of ​​the wall, for improving the current-passing capability of the first pole column, for improving the heat-diffusing capability of the first pole column, and for further improving the charging speed of the battery cell employing the casing assembly.

[0060] In some embodiments, the casing body has a second wall and a third wall that are installed opposite each other, and each of the second and third walls is provided with at least one first pole column.

[0061] In the above proposed technology, the first poles may be provided on two opposing sides of the casing body. When the first poles are provided on both opposing surfaces of the casing body, the positions of the first poles adjacent to each side of the active material coating area can all extend from the conductive part. The conductive part is connected by fitting with the adjacent first pole, thereby improving the problem of the tab being pulled by the first pole on the same side, which can cause the connection between the tab and the active material coating area to break, thereby improving the reliability of the battery cell. It should be noted that the first poles on both sides may be homologous or different, and the method of connecting the first poles on both sides to the conductive part may be homologous or different, and is not limited thereto.

[0062] In some embodiments, the casing body has multiple wall sections, a portion of which is a first setting wall section, the area of ​​the first setting wall section is larger than the area of ​​the other wall sections, and the first pole column is provided in the first setting wall section.

[0063] In the above proposed technology, the first pole column is riveted to the largest wall portion of the casing body, and because the area of ​​the wall portion connected to the first pole column is the largest, the operation of riveting the first pole column becomes easier, improving assembly efficiency and increasing the yield of battery cells.

[0064] In some embodiments, the casing body has a plurality of walls, at least one of which is a second setting wall, the battery cell further includes a pressure release section provided in the second setting wall, and the first pole column is provided in a wall other than the second setting wall.

[0065] In the above proposed technology, the first electrode column and the pressure release section are located on different walls. If the battery cell experiences thermal runaway, the discharged high-temperature medium is released through the pressure release section without coming into contact with the first electrode. In this way, the probability of a fire caused by the battery circuit coming into contact with the high-temperature medium can be reduced.

[0066] In some embodiments, the battery cell further includes a pressure relief portion provided in the casing cover and integrally molded with the casing cover.

[0067] In the above proposal, by integrally molding the pressure release section and the casing cover, the total number of parts in the battery cell can be reduced, and the welding process between the pressure release section and the casing body can be reduced. In other words, the process of connecting the pressure release section to the casing cover before and after connecting it to the casing body is unnecessary. In this way, the assembly efficiency of the battery cell can be improved, the cost of the welding process can be reduced, the possibility of welding position failure can be reduced, and the reliability of the battery cell can be improved.

[0068] In some embodiments, the casing body has a plurality of walls, at least one of which is a first wall, a first pole column is riveted to the first wall, and the thickness of the first wall is greater than the thickness of the other walls.

[0069] In the above proposed technology, the first wall is a casing wall connected to the first pole column, and the thickness of the first wall is greater than that of the other walls. On the one hand, because the thickness of the first wall itself is relatively large, the overall strength of the casing body can be improved, and the reliability of the battery cell in daily use can be further improved. On the other hand, because the thickness of the first wall is relatively large, the reliability of the riveting of the first pole column can be improved, and the yield of the battery cell can be improved. Next, assuming that the reliability of the riveting of the first pole column is satisfied, the thickness of the first wall can be the normal thickness, and the thickness of the other walls can be reduced. In this way, if the outer contour dimensions of the casing body are constant, the internal space of the casing body can be increased, and a larger active material coating area can be placed, which is advantageous in improving the energy density of the battery cell.

[0070] In some embodiments, the thickness of the casing cover is less than the thickness of the first wall.

[0071] In the above proposed technology, the first pole column is riveted to the first wall, and the casing cover does not need to be connected to the first pole column. Therefore, the strength requirements of the casing cover are relatively low, and its thickness may be less than that of the first wall. In this way, not only can material be saved, but if the outer contour dimensions of the casing are fixed, the relatively thin thickness of the casing cover allows for a larger space inside the casing. In this case, the casing can accommodate a larger active material coating area, which is advantageous for improving the energy density of the battery cell.

[0072] In some embodiments, the thickness of the casing cover is greater than the thickness of the other walls, except for the first wall adjacent to the casing cover.

[0073] In the above proposed technology, considering that the casing cover needs to seal the opening, it is necessary to provide adequate strength. Therefore, by setting the thickness of the casing cover to be greater than the thickness of the other walls, excluding the first wall adjacent to the casing cover, the overall strength of the casing is relatively good after the casing cover seals the opening, thereby reducing the probability of casing damage and improving the reliability of the battery cell.

[0074] In some embodiments, the opening is located at the bottom of the casing body.

[0075] In the above proposed technology, the opening of the casing body in the related technology is located at the top, and the casing cover is attached to the opening at the top of the casing body. Therefore, when processing the casing body of this structure, if the active material coating part is attached to the casing in this way, the bottom of the active material coating part (which may refer to the end of the active material coating part that is away from the conductive part) does not come into contact with the processed chamfer inside the casing body due to the processing chamfer. A certain space remains between them, and a partition wall is installed in this space, separating the active material coating part from the casing cover, thus creating wasted space inside the casing body. In this invention, since the opening is provided at the bottom of the casing body and the first pole column is riveted to the casing body, in this casing structure, after the active material coated portion is placed in the casing, there is no machined chamfer between the bottom of the active material coated portion and the casing cover. In other words, the partition wall between the bottom of the active material coated portion and the casing cover can be omitted, significantly reducing the gap between the bottom of the active material coated portion and the casing cover, which is advantageous for increasing the size of the active material coated portion and improving the energy density of the battery cell. Furthermore, since there is no machined chamfer near the bottom of the active material coated portion, the probability of accidental contact and damage between the active material coated portion and the machined chamfer can be significantly reduced, further reducing the outflow of the active material coating layer and improving the performance of the battery cell. At the same time, it can be understood that stress concentration at the corners of the active material coated portion can be reduced.

[0076] On the other hand, since the casing cover is installed at the bottom of the casing body, when the battery cells form a battery, it is generally necessary to fix the bottom of the casing to the bottom of the battery case. In this case, if vibration occurs during use, the casing cover is connected to the bottom of the box, so the amplitude received at the connection point between the casing cover and the casing body is relatively reduced, further reducing the probability of the casing cover and casing body cracking.

[0077] In some embodiments, the active material coated portion has a first end face adjacent to the casing cover, and the battery cell further includes an inner insulating member covering the battery core assembly, at least a portion of which is provided between the first end face and the casing cover, and the inner insulating member has opposing first and second surfaces, the first surface in contact with the first end face and the second surface in contact with the casing cover.

[0078] In the above proposed technology, the first surface of the inner insulating member is in contact with the first end face, and the second surface is in contact with the casing cover. In other words, if the present invention satisfies the requirement that the active material coated portion and the casing cover are insulated, the support plate between the active material coated portion and the casing cover in related technologies can be omitted. This, in turn, saves space within the casing body, is advantageous for increasing the dimensions of the active material coated portion, and further improves the energy density of the battery cell.

[0079] In some embodiments, the casing body has a first wall portion facing the casing cover, and the first pole column is provided in the first wall portion.

[0080] In the above proposed technology, the battery core assembly enters through the opening, and the conductive portion directly faces the first pole, thereby allowing the conductive portion to be connected to the first pole relatively easily and improving the assembly efficiency of the battery cell.

[0081] In a second aspect, the embodiment of the present application further provides a battery including the above-mentioned battery cell.

[0082] In the above proposed technology, since the first poles of any adjacent battery cells are connected to each other, when the battery vibrates or deforms, the first poles between any adjacent battery cells pull on each other. At this time, because the first poles are installed in the casing body, the force acting on the first poles does not act directly on the casing cover but is preferentially transmitted to the casing body. This extends the distance over which the force is transmitted to the connection point between the casing body and the casing cover. At the same time, when subjected to force, the casing body preferentially deforms to reduce the force received at the connection point between the casing body and the casing cover. This effectively reduces the probability of cracks occurring between the casing cover and the casing body during battery use, thereby improving the reliability of the battery cells.

[0083] In a third aspect, embodiments of the present application further provide an electrical device including the above-described battery cell or battery.

[0084] In the above proposed technology, the electrical device uses the above-mentioned battery or battery cell, and the probability of cracking between the casing cover and the casing body of the battery cell during use is relatively low, which is advantageous in improving the reliability of the battery and improving the performance of the electrical device.

[0085] In a fourth aspect, an embodiment of the present invention further provides a method for assembling a battery cell, the battery cell comprising a casing assembly including a casing and a first pole, and a battery core assembly including an active material coated portion and a conductive portion, the casing comprising a casing body and a casing cover, the assembly method comprising attaching the battery core assembly to the casing body, overlapping the conductive portion with the first pole, welding the conductive portion to the first pole from the outside of the casing body, and covering the casing body with the casing cover.

[0086] In the above proposed technology, when the battery cell of the present application is assembled, only the battery core assembly enters the casing. In this way, the number of components that enter the casing is relatively small, and the weight is relatively light (in related technologies, the battery core assembly, casing cover, and poles must be assembled first before being placed in the casing). Therefore, the operation of placing the battery core assembly into the casing is relatively easy, and it is also easy to overlap the conductive parts with the first poles, resulting in relatively high assembly efficiency. Because the internal space of the casing body is limited, welding the conductive parts to the first poles from the outside of the casing body facilitates the welding work and improves assembly efficiency. Welding from the outside effectively prevents metal foreign matter from entering the inside of the battery cell during the welding process, reducing the possibility of short circuits inside the battery cell due to metal foreign matter, and also facilitating the removal of metal foreign matter generated during the welding process. Finally, the assembly is completed by covering the casing body with the casing cover.

[0087] Next, the assembly method of the present invention can complete the assembly of a battery cell by using only the steps of attaching the battery core assembly to the casing body, overlapping the conductive part with the first pole column, welding the conductive part to the first pole column from the outside of the casing body, and covering the casing body with the casing cover. As a result, the overall assembly steps are relatively few, the assembly process is simplified, the assembly time is shortened, and this is advantageous in reducing the manufacturing cost of the battery cell.

[0088] In some embodiments, the battery cell further includes a support, the edge of which has a casing-in guide surface, and the step of attaching the battery core assembly to the casing body includes the step of attaching the support on the side of the active material coating that is close to the first pole column of the active material coating, such that the casing-in guide surface is positioned on the side of the support away from the active material coating, and the step of attaching the battery core assembly to the casing body by the guidance of the casing-in guide surface.

[0089] In the above proposed technology, the support and battery core assembly can be pre-assembled during assembly. The assembled assembly is then attached to the casing. During attachment, the support is positioned at the front end of the active material coating area, meaning the support enters the casing before the active material coating area. This reduces the difficulty of the support entering the casing by utilizing the casing's guide surface, and also provides protection for the active material coating area. This reduces the probability of scratches between the active material coating area and the casing, improving assembly efficiency and product yield. Furthermore, the contact area between the support and the active material coating area can be increased, mitigating stress concentration problems and allowing for the omission of other structural components.

[0090] In some embodiments, the battery cell further includes a support having a relief hole, and the step of overlapping the conductive portion onto the first pole column includes the step of passing the conductive portion through the relief hole and the step of overlapping the conductive portion onto the first pole column.

[0091] In the above proposed technology, separating the active material coated area from the casing using a support is advantageous in improving the reliability of the battery cell. Furthermore, providing a relief hole in the support guides and restrains the conductive part from fitting with the first pole post by passing through the relief hole. This eliminates the need to route the conductive part away from the edge of the support to approach the first pole post during the battery cell assembly process, thereby simplifying the arrangement of the conductive part, saving material for the conductive part, and reducing costs. Moreover, the support can support and guide the fitting between the conductive part and the first pole post, reducing the risk of short-circuit connection between the conductive part and the active material coated area, and further improving the reliability of the battery cell.

[0092] In some embodiments, the first pole column has a first housing groove, the surface of the first pole column facing the active material coating is the inner end face of the pole column, the groove opening of the first housing groove is formed on the inner end face of the pole column, and the step of overlapping the conductive portion with the first pole column includes the step of extending the conductive portion into the first housing groove and the step of overlapping the conductive portion with the groove wall of the first housing groove.

[0093] In the above proposed technology, since the first pole has a first receiving groove during the process of overlapping the conductive part with the first pole, the alignment of the conductive part and the first pole is made relatively easy. When the conductive part is welded to the first pole from outside the casing body in this way, the stability of the conductive part on the first pole can be improved, the welding quality can be improved, and this is advantageous for improving the performance of the battery cell.

[0094] In some embodiments, the first pole column has a second housing groove, the surface of the first pole column away from the active material coated portion is the outer end face of the pole column, the groove opening of the second housing groove is formed on the outer end face of the pole column, the second housing groove communicates with the inside of the casing through a first through hole, and the step of superimposing the conductive portion onto the first pole column includes the step of superimposing the conductive portion through the first through hole and housing at least a portion of it in the second housing groove, and the step of superimposing the conductive portion onto the groove wall of the second housing groove and / or the hole wall of the first through hole.

[0095] In the above proposed technology, the second housing groove allows the portion where the conductive part overlaps with the first pole column to be exposed from the outside of the casing. This makes it easier to weld the conductive part and the first pole column from the outside, resulting in relatively easy operation and improved assembly efficiency.

[0096] In some embodiments, the battery cell further includes a first cover plate, and after welding the conductive portion to the first pole post, the assembly method further includes welding the first cover plate to the first pole post so as to seal the groove opening of the second housing groove.

[0097] In the above proposed technology, by installing the first cover plate and sealing the groove opening of the second housing groove, leakage of the electrolyte inside the casing from the groove opening of the second housing groove can be prevented. Furthermore, since the first cover plate seals the groove opening of the second housing groove and is electrically connected to the first pole column, it is possible to easily achieve an indirect electrical connection between the first pole column and the bus member using the first cover plate. This is also advantageous in increasing the connection area of ​​the electrical connection and, consequently, in reducing the resistance of the electrical connection. In addition, the first cover plate can separate the welded portion between the conductive part and the first pole column from the welded portion between the first pole column and the bus member, thereby reducing the influence of the welded portion between the conductive part and the first pole column on the welded portion between the first pole column and the bus member, and improving the welding quality of the first pole column and the bus member.

[0098] To further clarify the technical concept of the embodiments of this application, the drawings used in the embodiments are briefly introduced below. However, it should be understood that these drawings only show some embodiments of this application and should therefore not be considered limiting in scope. Those skilled in the art can obtain other relevant drawings based on these drawings without any creative work. [Brief explanation of the drawing]

[0099] [Figure 1] This is a schematic diagram of the structure of a vehicle provided by some embodiments of the present application. [Figure 2] This is an exploded view of the structure of a battery provided by some embodiments of the present application. [Figure 3] This is a schematic diagram of the structure of a battery cell provided by some embodiments of the present application. [Figure 4] This is a cross-sectional view of the internal structure, taken along the AA direction in Figure 3. [Figure 5] This is a localized, enlarged schematic diagram of location I in Figure 4. [Figure 6] This is a schematic diagram of the structure of a battery cell provided by some embodiments of the present application. [Figure 7]This is an orthographic projection of a battery cell provided by some embodiments of the present application. [Figure 8] This is a cross-sectional view along the line A-A in Figure 7. [Figure 9] This is a schematic diagram of the structure of a battery cell provided by some embodiments of the present application. [Figure 10] This is an assembly diagram of a second pole, a battery core assembly, and a casing, provided in some embodiments of the present application. [Figure 11] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 12] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 13] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 14] This is a schematic diagram of a local cross-section of a battery core assembly provided by some embodiments of the present application. [Figure 15] This is a convergence diagram of multiple types of tabs for a battery core assembly provided by some embodiments of the present application. [Figure 16] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 17] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 18] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 19] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 20] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 21] This is a close-up view of area B in Figure 6. [Figure 22] These are orthographic projections of several types of first pole columns provided by some embodiments of the present application. [Figure 23] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 24] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 25] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 26] This is an exploded view of the structure of a battery cell provided by some embodiments of the present application. [Figure 27] This is a schematic diagram of a local cross-section of a casing assembly provided by some embodiments of the present application. [Figure 28] Figure 27 is an exploded view of the casing assembly. [Figure 29] Figure 28 is an exploded view of the structure of the first cover plate. [Figure 30] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 31] Figure 30 is an exploded view of the structure of a battery cell. [Figure 32] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 33] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 34] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 35] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 36] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 37] This is a schematic diagram of the mating of a battery core assembly and support provided in some embodiments of the present application. [Figure 38] This is a cross-sectional view along the line C-C in Figure 37. [Figure 39] This is a schematic diagram of the structure of an integrated support provided by several embodiments of the present application. [Figure 40] This is a schematic diagram of the structure of a separate support provided by several embodiments of the present application. [Figure 41] This is a schematic local cross-sectional view of a battery core assembly and support provided in some embodiments of the present application. [Figure 42] This is an exploded view of the structure of a battery core assembly, support, and casing assembly provided by some embodiments of the present application. [Figure 43] This is an exploded view of the structure of the first pole column, casing, and seal pad provided by several embodiments of the present application. [Figure 44] Figure 43 is an assembly diagram of the first pole column, casing, and seal pad. [Figure 45] This is a schematic diagram of the structure of the first pole column provided by several embodiments of the present application. [Figure 46] Figure 45 is an assembly diagram of the first pole column, casing, and seal pad. [Figure 47] Figure 45 is an exploded view of the structure of the first pole column. [Figure 48] This is an orthographic projection of a battery cell provided by some embodiments of the present application. [Figure 49] This is an orthographic projection of a battery cell provided by some embodiments of the present application. [Figure 50] Figure 49 is a cross-sectional view along the DD line. [Figure 51] This is a schematic cross-sectional view of a casing assembly provided by some embodiments of the present application. [Figure 52] This is a schematic cross-sectional view of a casing assembly provided by some embodiments of the present application. [Figure 53] This is an orthographic projection of a battery cell provided by some embodiments of the present application. [Figure 54] Figure 53 is a cross-sectional view along the EE line. [Figure 55] This is a schematic diagram of a local cross-section of a battery cell provided by some embodiments of the present application. [Figure 56] This is a schematic diagram of the structure of a casing cover provided by some embodiments of the present application. [Figure 57]This is a schematic diagram 2 of the structure of a battery cell provided by some embodiments of the present invention. [Figure 58] Figure 3 shows a schematic diagram of the structure of a battery cell provided by several embodiments of the present invention. [Figure 59] This is a localized, enlarged schematic diagram of location II in Figure 4. [Figure 60] This is a top view of a battery cell provided by some embodiments of the present application. [Figure 61] This is flowchart 1 of a battery cell assembly method provided by some embodiments of the present invention. [Figure 62] This is flowchart 2 of a battery cell assembly method provided by some embodiments of the present invention. [Figure 63] This is flowchart 3 of a battery cell assembly method provided by several embodiments of the present invention. [Figure 64] This is flowchart 4 of a battery cell assembly method provided by some embodiments of the present invention. [Figure 65] This is flowchart 5 of a battery cell assembly method provided by some embodiments of the present invention. [Figure 66] This is flowchart 6 of a battery cell assembly method provided by some embodiments of the present invention. [Modes for carrying out the invention]

[0100] To further clarify the purpose, technical proposal and advantages of the embodiments of this application, the technical proposal of the embodiments of this application will be clearly described below in conjunction with the drawings of the embodiments of this application. However, it should be clear that the embodiments described are only a selection of embodiments of this application, not all embodiments. All other embodiments that a person skilled in the art could obtain without creative work based on the embodiments of this application also fall within the scope of the claims of this application.

[0101] Unless otherwise defined, all technical and scientific terms used in this Application have the same meaning as those generally understood by those skilled in the art relating to the Application. Terms used in the Specification of this Application are for illustrative purposes only and are not intended to limit the Application. The terms “including” and “having,” and any variations thereof, in the description of the Specification, Claims, and the Drawings are intended to cover non-exclusive inclusion. Terms such as “first,” “second,” etc., in the Specification, Claims, or the Drawings are used to distinguish different subjects and are not intended to indicate a particular order or priority.

[0102] In this application, any reference to “Examples” means that certain features, structures, or characteristics described in relation to the Examples may be included in at least one Example of this Application. The occurrence of such phrase at each location in the Specification does not necessarily refer to the same Example, nor do they represent mutually exclusive, independent, or substitutable Examples.

[0103] In this application, the term "and / or" simply describes a related relationship that explains the related objects, indicating that three types of relationships are possible. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. In addition, the symbol " / " in this application generally indicates that the preceding and following related objects are in an "or" relationship.

[0104] In the embodiments of this application, the same drawing symbols represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the dimensions such as thickness, length, and width of various components in the embodiments of this application shown in the drawings, as well as the overall dimensions such as thickness, length, and width of the integrating device, are merely illustrative and do not constitute any limitation to this application.

[0105] In this application, "multiple" refers to two or more (including two).

[0106] In this application, the battery cell may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, and the embodiments of this application are not limited to these. The battery cell may be cylindrical, flattened, rectangular, or have other shapes, and the embodiments of this application are not limited to these. Battery cells are generally classified into three types according to the encapsulation method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, but the embodiments of this application are not limited to these either.

[0107] The batteries referred to in the embodiments of this application refer to a single physical module containing one or more battery cells to provide higher voltage and capacity. For example, the batteries referred to in this application may be a battery module or a battery pack. If the battery is a battery module, the battery module consists of multiple battery cells. If the battery is a battery pack, the battery pack can consist directly of a case and multiple battery cells installed within the case, or it may be configured so that the battery modules are first composed of battery cells and then the battery modules are installed within the case. The case can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0108] For example, a battery cell may typically include a casing for housing the electrode assembly and electrolyte, the electrode assembly and electrolyte, and the casing may be provided with at least one positive electrode column and at least one negative electrode column. The electrode assembly consists of a positive electrode piece, a negative electrode piece and a separator film. The material of the separator film is not particularly limited and may be, for example, polypropylene or polyethylene.

[0109] A positive electrode piece generally includes a positive electrode current collector and a positive electrode active material layer applied directly or indirectly on the positive electrode current collector. A positive electrode current collector without the positive electrode active material layer protrudes from a positive electrode current collector with the positive electrode active material layer applied, while a positive electrode current collector without the positive electrode active material layer is a positive electrode tab sheet.

[0110] The negative electrode piece generally includes a negative electrode current collector and a negative electrode active material layer, where the negative electrode active material layer is directly or indirectly coated onto the negative electrode current collector, and the negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer, forming a negative electrode tab sheet.

[0111] The electrode assembly may have a winding structure or a laminated structure. During processing, the positive electrode piece, negative electrode piece, and separator film can be wound or laminated in sequence to obtain the electrode assembly. In the electrode assembly, multiple positive electrode tabs are laminated to form an electrical connection with the positive electrode column, and multiple negative electrode tab sheets are laminated to form an electrical connection with the negative electrode column.

[0112] A battery cell functions primarily by relying on the movement of metal ions between the positive and negative electrode pieces. Taking a lithium-ion battery as an example, the positive electrode current collector may be made of aluminum, the positive electrode active material layer may be made of lithium cobalt oxide, lithium iron phosphate, lithium ternary, or lithium manganese oxide, the negative electrode current collector may be made of copper, and the negative electrode active material layer may be made of carbon or silicon. During the charging and discharging process, Li+ ions repeatedly insert and remove between the two electrodes. During charging, Li+ ions are removed from the positive electrode and inserted into the negative electrode via the electrolyte, making the negative electrode lithium-rich, and the reverse occurs during discharging.

[0113] In recent years, new energy vehicles have made remarkable progress, and in the electric vehicle sector, batteries play an indispensable and crucial role as the power source for electric vehicles. As a core component of new energy vehicles, batteries must meet high demands in terms of both energy density and reliability.

[0114] In manufacturing battery cells using related technologies, an active material layer is applied to a current collector and then cut to obtain an electrode sheet consisting of a current collector with the active material layer applied (referred to as the active material coated portion) and a current collector without the active material layer applied (referred to as a tab sheet). Next, a positive electrode piece, a negative electrode piece, and a separator film are sequentially laminated or wound to obtain a battery core assembly. Multiple tab sheets are laminated and installed in the electrode assembly to form tab portions. The tab portions are connected to an adapter sheet to form a conductive portion, or the tab portions themselves form a conductive portion, and the active material coated portion and the conductive portion form the battery core assembly. Electrode columns are installed in the casing of the battery cell, and during the manufacturing of the battery cell, the conductive portion is usually welded to the electrode column to ensure normal charging and discharging operations.

[0115] However, the inventors discovered that in related technologies, the casing has an opening at the top, the poles are installed in the casing cover, the casing cover covers the opening and is welded to the casing, and the welded seam is located at the top of the battery cell. However, when battery cells constitute a battery, the bottom of the casing needs to be fixed, and the poles of adjacent battery cells are connected via conductive members (such as busbars). Since the poles are installed in the casing cover, if vibration or deformation occurs during the battery's operation, the conductive members pull on the poles, and the tensile force of the conductive members on the poles is easily transmitted to the welded seam between the casing cover and the casing, causing material fatigue cracking at the welded seam between the casing cover and the casing, which affects the reliability of the battery cell.

[0116] Based on the above considerations, the inventors have conducted research to improve the reliability of battery cells. By changing the mounting position of the poles and installing the poles on the casing body, the casing cover of the battery cell can no longer be directly connected to the poles. In this way, when the battery cells pull on each other due to vibration and deformation during the process of forming and using the battery, the force acting on the first pole is installed on the casing body. Therefore, the force acting on the first pole does not act directly on the casing cover but is preferentially transmitted to the casing body. This extends the distance over which the force is transmitted to the welded joint between the casing body and the casing cover. At the same time, the casing body preferentially deforms when subjected to force, reducing the force received at the welded joint between the casing body and the casing cover. This effectively reduces the probability of cracks occurring at the welded joint between the casing body and the casing cover during the battery's use, thereby improving the reliability of the battery cells.

[0117] Embodiments of the present application provide an electrical device that uses the battery cell of the present disclosure as a power source, which may be, but is not limited to, a mobile phone, tablet, laptop computer, electric toy, power tool, electric scooter, electric car, steamship, or aerospace aircraft. Among these, electric toys may include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys, while aerospace aircraft may include airplanes, rockets, space shuttles, or spacecraft.

[0118] The following embodiments will be described using the example that the electrical device in one embodiment of the present application is a vehicle, for the sake of clarity. Referring to Figure 1, Figure 1 is a schematic diagram of the structure of an electrical device 1000 which is a vehicle provided in several embodiments of the present application. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or a range extender vehicle, etc. A battery 100 is installed inside the vehicle, and the battery 100 may be installed in the bottom, front, or rear of the vehicle. The battery 100 is used to supply power to the vehicle, and for example, the battery 100 can function as the operating power source of the vehicle. The vehicle may further include a controller 200 and a motor 300, the controller 200 controlling the battery 100 to supply power to the motor 300, and is used, for example, to meet the demands for operating power during vehicle starting, navigation, and driving. In some embodiments of the present application, the battery 100 can be used not only as the operating power source of the vehicle but also as the driving power source of the vehicle, and can provide driving force to the vehicle in place of or in part of fuel or natural gas.

[0119] Referring to Figure 2, which is an exploded view of a structure in which a battery cell 10 provided in several embodiments of the present application is 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 provides assembly space for the battery cells 10, and the case 20 can employ a variety of structures. In some embodiments, the case 20 may include a first case 201 and a second case 202, the first case 201 and the second case 202 covering each other, and the first case 201 and the second case 202 together limit the assembly space for housing the battery cells 10. The second case 202 may be a hollow structure with one end open, and the first case 201 may be a plate-like structure, and the first case 201 covers the open side of the second case 202 so that both the first case 201 and the second case 202 limit the assembly space, and both the first case 201 and the second case 202 may be hollow structures with one side open, and the open side of the first case 201 covers the open side of the second case 202. Of course, the case 20 in which the first case 201 and the second case 202 are formed may be of various shapes, such as a cylinder or a rectangular parallelepiped.

[0120] In the battery 100, multiple battery cells 10 can be connected in series, in parallel, or in series-parallel, where series-parallel connection refers to multiple battery cells 10 being connected in both series and parallel. Multiple battery cells 10 may be directly connected in series, in parallel, or in series-parallel, and the entire assembly composed of multiple battery cells 10 may be housed in a case 20. Of course, the battery 100 may be configured such that multiple battery cells 10 are first connected in series, in parallel, or in series-parallel to form a battery module, and then the multiple battery modules are connected in series, in parallel, or in series-parallel to form a single whole, which is then housed in a case 20. The battery 100 may further include other structures; for example, the battery 100 may further include bus members for realizing electrical connections between multiple battery cells 10.

[0121] Referring to Figure 3, which is a schematic diagram of a battery cell 10 provided in several embodiments of the present application, the battery cell 10 is a rectangular parallelepiped, and the height direction of the battery cell 10 is the first direction Z, the thickness direction of the battery cell 10 is the second direction X, and the length direction of the battery cell is the third direction Y. The first direction Z, the second direction X, and the third direction Y are perpendicular to each other in pairs. However, the present application is not limited to these, and in other embodiments, the battery cell 10 may be cylindrical, flattened, or have other shapes.

[0122] As shown in Figures 3 to 6, the battery cell 10 includes a casing assembly 1 and a battery core assembly 2.

[0123] Casing assembly 1 includes a casing 11 which includes a casing body 111 and a casing cover 112, and a first pole post 12, wherein the casing body 111 has an opening 111a, the casing cover 112 covers the opening 111a, and the first pole post 12 is installed in the casing body 111. Battery core assembly 2 includes an active material coated portion 21 which is housed in the casing body 111, and a conductive portion 22 which electrically connects the active material coated portion 21 and the first pole post 12.

[0124] The casing 11 is provided with poles, which are used for electrical connection to the battery core assembly 2 to ensure that the charging and discharging operations of the battery cell 10 are performed normally. Generally, there are at least two poles, specifically at least one positive pole and at least one negative pole. For example, if there are two poles, one is a positive pole and one is a negative pole, and both are electrically connected to the positive and negative output positions of the battery core assembly 2, respectively. Also, for example, if there are four poles, two can be positive poles and two can be negative poles. At least one of the multiple poles is the first pole 12, which may be either a positive pole or a negative pole.

[0125] In the embodiment of the present invention, the battery core assembly 2 includes an active material coated portion 21 and a conductive portion 22 housed within the casing 11. The active material coated portion 21 is a part of the battery core assembly 2 to which an active material is coated, and which can assist in the desorption of metal ions during the charging and discharging process of the battery cell 10. The conductive portion 22 is a metal structure that electrically connects the active material coated portion 21 and the electrode column, and is electrically connected to the active material coated portion 21 via the conductive portion 22 so that the charging and discharging operations of the battery cell 10 can be performed even if an active material is not coated on it.

[0126] The active material coating section 21 is divided into a positive electrode active material coating section and a negative electrode active material coating section. The positive electrode active material coating section includes a portion of the positive electrode current collector to which the positive electrode active material layer is coated, and the negative electrode active material coating section includes a portion of the negative electrode current collector to which the negative electrode active material layer is coated. The conductive section 22 is divided into a positive electrode conductive section and a negative electrode conductive section. The positive electrode conductive section electrically connects the positive electrode active material coating section and the positive electrode column, and the negative electrode conductive section electrically connects the negative electrode active material coating section and the negative electrode column.

[0127] In the above proposed technology, since the first poles 12 of any adjacent battery cells 10 are connected to each other in the battery 100, when the battery 100 vibrates or deforms, the first poles 12 between any adjacent battery cells 10 pull on each other. At this time, since the first poles 12 are installed in the casing body 111, the force acting on the first poles 12 does not act directly on the casing cover 112, but is preferentially transmitted to the casing body 111. This extends the distance over which the force is transmitted to the welded joint between the casing body 111 and the casing cover 112. At the same time, when subjected to force, the casing body 111 preferentially deforms to reduce the force received by the welded joint between the casing body 111 and the casing cover 112. This effectively reduces the probability of cracks occurring in the welded joint between the casing cover 112 and the casing body 111 during battery use, thereby improving the reliability of the battery cells 10.

[0128] In the embodiment of the present invention, when Figures 7 and 8 are combined, a housing portion 121 is installed on the first pole column 12, and at least a portion of the conductive portion 22 is housed in the housing portion 121.

[0129] Referring to the preamble, there may be multiple pole columns, and at least one of the multiple pole columns is a first pole column 12, the first pole column 12 is a pole column on which a housing portion 121 is formed, the housing portion 121 is a virtual structure having a housing space, and may be a groove-shaped structure, a perforated structure, or a composite structure of a groove-shaped structure and a perforated structure. In other words, all of the pole columns of the casing 11 may be first pole columns 12 forming a housing portion 121, or some of the pole columns of the casing 11 may be first pole columns 12 forming a housing portion 121. If some of the pole columns of the casing 11 are first pole columns 12 forming a housing portion 121, the remaining pole columns in the casing 11 are second pole columns 15 (see Figures 9 and 10) that do not have a housing portion 121. Of these, at least some means that the conductive portion 22 may be completely housed in the housing portion 121, or a part of the conductive portion 22 may be housed in the housing portion 121. Since the housing section 121 is installed on the first pole column 12, the hollow structure of the housing section 121 can reduce the weight of the pole column 12 to some extent, thereby improving the gravitational energy density of the battery cell 10 and the battery 100.

[0130] Furthermore, by housing part or all of the conductive portion 22 within the housing portion 121, the portion of the conductive portion 22 located within the housing portion 121 can occupy space within the first pole column 12, thereby reducing the space occupied by the conductive portion 22 within the casing 11. If the dimensions of the casing 11 remain constant, some space can be saved within the casing 11 to accommodate a larger active material coated portion 21, thereby improving the volumetric energy density of the battery cell 10. For example, if the conductive portion 22 is drawn out from the side of the active material coated portion 21 adjacent to the first pole column 12, the space occupied by the conductive portion 22 between the active material coated portion 21 and the pole column 12 can be saved, thereby increasing the dimension of the active material coated portion 21 in the direction in which the conductive portion 22 is drawn out, reducing the distance between the active material coated portion 21 and the first pole column 12, thereby improving the energy density of the battery cell 10.

[0131] Furthermore, by housing at least a portion of the conductive portion 22 within the housing portion 121, the space occupied by the battery cell 10 itself can be reduced, allowing more battery cells 10 to be housed in a battery 100 of the same volume, thereby improving the volumetric energy density of the battery 100. Additionally, by housing at least a portion of the conductive portion 22 within the housing portion 121 so as to occupy space within the first pole column 12, the redundancy of the conductive portion 22 in the casing 11 is reduced to at least some extent, reducing the probability of short circuits between the conductive portion 22 and the active material coated portion 21, reducing the probability of short circuits in the battery cell 10, and improving the operational reliability and stability of the battery cell 10 and the battery 100. Finally, by housing at least a portion of the conductive portion 22 in the housing portion 121 of the first pole column 12, the connection between the conductive portion 22 and the first pole column 12 is facilitated.

[0132] In some selective embodiments of the present invention, when Figures 6 to 8 are combined, each of the multiple poles of the casing assembly 1 is a first pole 12 having a housing portion 121, in which case more conductive portions 22 can be housed within all of the first poles 12, thereby further improving the volumetric energy density of the battery cell 10.

[0133] In several other selective embodiments of the present invention, when Figures 9 and 10 are combined, at least one of the poles of the casing assembly 1 is a first pole 12 having a housing portion 121, and at least one is a second pole 15 without a housing portion 121, thereby allowing for flexible selection and combination of the first pole 12 and the second pole 15 according to actual needs such as energy density and cost, thereby improving the applicability of the battery cell 10.

[0134] In some selective embodiments, combining Figures 9 and 10, a relief groove 18 is limited between the second pole 15 and the casing 11, and at least a portion of the conductive portion 22 is housed in the relief groove 18. This reduces the space occupied by the conductive portion 22 within the casing 11 to some extent, which is advantageous for improving energy density and mitigating short-circuit problems caused by the redundancy of the conductive portion 22.

[0135] To simplify the explanation, the following describes an embodiment in which all poles in the casing 11 are first poles 12 forming a housing portion 121. Furthermore, as an example, the casing assembly 1 in some embodiments of the present application may be provided with only one first pole 12, which includes two insulating portions, one being a positive pole and the other a negative pole.

[0136] In the embodiment of the present application, the position of the housing portion 121 may be on the side of the first pole column 12 facing the active material coated portion 21, or it may be on the side of the first pole column 12 away from the active material coated portion 21. Exemplarily, combining Figures 11 and 12, when the housing portion 121 is located on the side of the first pole column 12 facing the active material coated portion 21, the housing portion 121 has a first housing groove 12110, the surface of the first pole column 12 facing the active material coated portion 21 is the inner end face 122 of the pole column, the groove opening of the first housing groove 12110 is formed on the inner end face 122 of the pole column, and at least a part of the conductive portion 22 is housed in the first housing groove 12110.

[0137] For example, the first accommodating groove 12110 may be a groove body, which is a groove-like structure having a certain depth. For example, if the first pole column 12 is installed on the upper end wall of the casing 11 and the inner end face 122 of the pole column is the lower surface of the first pole column 12, the first accommodating groove 12110 is formed as an accommodating groove with a groove opening that faces downward and a groove wall that is recessed upward. Alternatively, if the first pole column 12 is installed on the lower end wall of the casing 11 and the inner end face 122 of the pole column is the upper surface of the pole column 12, the first accommodating groove 12110 is formed as an accommodating groove with a groove opening that faces upward and a groove wall that is recessed downward.

[0138] In the above proposed technology, on the one hand, by providing a first housing groove 12110 in the first pole column 12, the weight of the first pole column 12 can be reduced to some extent, thereby improving the gravimetric energy density of the battery cell 10 and the battery 100. On the other hand, since the opening of the first housing groove 12110 is formed on the inner end face 122 of the pole column, and the inner end face 122 is the surface of the first pole column 12 that is close to the active material coated portion 21, the first housing groove 12110 can be opened toward the active material coated portion 21, and furthermore, the conductive portion 22 can easily extend into the first housing groove 12110, improving assembly efficiency. In addition, such a first housing groove 12110 is easy to process, which can improve production efficiency.

[0139] Furthermore, the first housing groove 12110 is easy to process and has a relatively large volume, allowing it to accommodate more conductive parts 22. At the same time, since the first housing groove 12110 is open toward the active material coating part 21, it also functions as a buffer and temporary storage structure for the electrolyte, allowing more electrolyte to be contained within the casing 11. As the electrolyte is consumed during the charging and discharging process of the battery cell 10, a larger amount of electrolyte can extend the service life of the battery cell 10. Moreover, since the first housing groove 12110 is open toward the active material coating part 21, it can also be used as a gas containment and buffer structure for gases generated inside the battery core assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

[0140] Furthermore, since the first housing groove 12110 is located inside the first pole post 12, it is difficult for external foreign matter and impurities to enter the first housing groove 12110, thereby reducing the influence of external foreign matter and impurities on the battery core assembly 2, improving the stability and reliability of the operation of the battery core assembly 2, and consequently further improving the stability and reliability of the battery cell 10 and the battery 100. The first housing groove 12110 is located inside the first pole post 12, and at least a portion of the conductive part 22 is housed in the first housing groove 12110, making it easy to restrict the position of the conductive part 22 from inside the first pole post 12, and making it easy to connect the conductive part 22 to the first pole post 12.

[0141] When Figure 11 is combined, the connection method between the first pole post 12 and the casing 11 is not limited in the embodiment of the present application. For example, it may be by welding or by riveting. For example, if the two are fitted together by riveting, the casing 11 has a mounting hole 113, and the first pole post 12 is attached to the mounting hole 113 by riveting. Of course, if the two are fitted together by welding or other methods, the casing 11 may have a mounting hole 113, and it is understood that the first pole post 12 is attached to the mounting hole 113. It should be explained that the mounting hole 113 may be specifically installed in the casing body 111.

[0142] By selectively combining Figure 11, the first housing groove 12110 can be positioned corresponding to the location of the mounting hole 113. In other words, in the projection plane perpendicular to the axial R of the first pole column 12, the orthographic projection of the first housing groove 12110 lies within the orthographic projection range of the mounting hole 113. Therefore, the first housing groove 12110 can have a greater depth to accommodate more conductive parts 22, and furthermore, the space occupied by the conductive parts 22 within the casing 11 can be reduced more significantly.

[0143] In some embodiments, when Figure 11 is combined, a mounting hole 113 is provided in the casing 11 and the first pole post 12 is attached to the mounting hole 113, the depth H1 of the first housing groove 12110 is greater than or equal to the minimum distance H2 from the inner end face 122 of the pole post to the mounting hole 113 along the axial radius R of the first pole post 12.

[0144] It should be noted that the specific shape of the first accommodating groove 12110 is not limited and may be regular or irregular in shape. For example, it may be a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a semi-elliptical groove with an elliptical cross-section and gradually changing cross-sectional dimensions. Therefore, the depth H1 of the first accommodating groove 12110 refers to the maximum depth of the first accommodating groove 12110 along the axial radius R of the first pole column 12.

[0145] In the axial radius R of the first pole column 12, the depth H1 of the first housing groove 12110 is greater than or equal to the minimum distance H2 from the inner end face 122 of the pole column to the mounting hole 113, allowing for full utilization of the volume of the first pole column 12. This makes it advantageous to give the first housing groove 12110 a relatively large depth, accommodating more conductive parts 22, further reducing the space occupied by the conductive parts 22 within the casing 11, thereby further improving the energy density of the battery cell 10 and further reducing the redundancy of the conductive parts 22 within the casing 11. At the same time, because the first housing groove 12110 has a relatively large depth, it can accommodate gases generated in the battery core assembly 2, ensuring the reliability and stability of the battery cell 10, and also allowing for the accommodation of more electrolyte to ensure the service life of the battery cell 10.

[0146] Furthermore, it should be explained that the volume of the first housing groove 12110 is not limited. For example, in some specific examples, the volume of the first housing groove 12110 for housing the conductive part 22 (denoted as the first volume V1) is 298 mm³. 3The above may be the case, whereby the first accommodating groove 12110 can have a relatively sufficient space for accommodating the conductive part 22 and facilitate the welding between the conductive part 22 and the first pole 12. On the other hand, when the first volume V1 of the first accommodating groove 12110 is less than 298 mm 3 the ability of the first accommodating groove 12110 to accommodate the conductive part 22 becomes relatively low, and the welding between the conductive part 22 and the first pole 12 becomes difficult.

[0147] It should be noted 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 the second volume V3) required for the first accommodating groove 12110 to accommodate other members other than the conductive part 22, that is, V1 = V2 - V3. As can be understood, when the first accommodating groove 12110 does not need to accommodate other parts other than the conductive part 22, the second volume V3 can be 0 mm 3 For example, the first volume V1 of the first accommodating groove 12110 can be 300 mm 3 ~1500 mm 3 For example, it can be 300 mm 3 400 mm 3 500 mm 3 600 mm 3 700 mm 3 800 mm 3 1000 mm 3 1200 mm 3 1400 mm 3 1500 mm 3 and so on.

[0148] By combining Figures 11 and 12, in order to ensure the stability and reliability of the electrical connection between the active material coated portion 21 and the first pole column 12, in some embodiments of the present application, the electrical connection position between the conductive portion 22 and the first pole column 12 may be located on the groove wall of the first housing groove 12110. Exemplarily, the conductive portion 22 and the first pole column 12 can be electrically connected by welding, and the electrical connection position is the welding position between the conductive portion 22 and the first pole column 12. At the same time, the welding method between the conductive portion 22 and the first pole column 12 is not limited, and may be, for example, laser welding, and depending on factors such as the position, angle, or structure of the welding area, vertical welding, inclined welding, overlap welding, edge welding, etc. can be selected. In other embodiments of the present application, the conductive portion 22 and the first pole column 12 can be electrically connected by other methods instead of welding, such as installing conductive adhesive or conductive pins for connection. To simplify the explanation, the following explanation will use the example that the conductive part 22 and the first pole column 12 are electrically connected by welding, and the welding position is the electrical connection position between the conductive part 22 and the first pole column 12.

[0149] Combining Figures 11 and 12, more specifically, the first pole post 12 includes a first end wall 12111 and a first side wall 12113, the first end wall 12111 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 to form a first housing groove 12110, and the location where the conductive portion 22 is electrically connected to the first pole post 12 is located on the first end wall 12111 and / or the first side wall 12113. In other words, the conductive portion 22 may be welded to at least one of the first end wall 12111 and the first side wall 12113.

[0150] In the above proposed technology, by setting the electrical connection position between the conductive part 22 and the first pole column 12 on at least one of the first end wall 12111 and the first side wall 12113, the first accommodating groove 12110 not only serves to accommodate at least a part of the conductive part 22, but the groove wall of the first accommodating groove 12110 also serves to realize an electrical connection with the conductive part 22. As a result, the structure of the first pole column 12 can be simplified, the processing of the first pole column 12 can be made easier, the structure of the conductive part 22 can be simplified, the redundancy of the conductive part 22 can be reduced, and the cost of the conductive part 22 can be reduced. Furthermore, by utilizing the groove wall of the first housing groove 12110 to achieve electrical connection with the conductive part 22, the area for electrical connection between the conductive part 22 and the first pole column 12 can be made relatively large, which not only reduces the difficulty of electrical connection but also improves the reliability and stability of the electrical connection, and ultimately improves the performance of the battery cell 10. Also, if the position where the conductive part 22 is electrically connected to the first pole column 12 is located on the first end wall 12111, it becomes easier to connect the conductive part 22 and the first end wall 12111 from the outside.

[0151] Furthermore, by positioning the electrical connection point between the conductive part 22 and the first pole post 12 within the first housing groove 12110, it is possible to avoid the electrical connection point protruding outside the first pole post 12 and occupying space other than the first pole post 12. Moreover, the electrical connection point is protected by the first pole post 12, thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole post 12.

[0152] Furthermore, in the embodiment of the present invention, the first end wall 12111 is configured as a sealed structure without through holes so as to isolate the first housing groove 12110 from the external space of the casing 11, thereby avoiding the problem of electrolyte leaking from the first housing groove 12110 within the casing 11.

[0153] Combining Figures 11 and 12, in several selective embodiments, the local shape of the conductive portion 22 matches and is installed in close contact with the local shape of the first end wall 12111, thereby achieving electrical connection, and the position where the conductive portion 22 is electrically connected to 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 planar, the local portion of the conductive portion 22 is also planar and is installed in close contact with the first end wall 12111, and is electrically connected by its close position, which may be, for example, welded. This can increase the electrical connection area and improve the reliability and stability of the electrical connection.

[0154] Furthermore, if the electrical connection between the conductive portion 22 and the first end wall 12111 is welded, the first end wall 12111 is located on the side of the first housing groove 12110 away from the active material coated portion 21, which facilitates the welding operation. For example, welding may be performed from the side of the first pole column 12 away from the active material coated portion 21.

[0155] It should be explained that the shape of the first end wall 12111 is not limited and may be, for example, a flat plate or an arc-shaped plate. Here, if the first end wall 12111 is a flat plate structure, it is positioned at an angle with the axial direction R of the first pole column 12. For example, it may be a flat plate structure perpendicular to the axial direction R of the first pole column 12, or it may be an inclined plate structure not perpendicular to the axial direction R of the first pole column 12, but the direction of inclination is not limited.

[0156] Of course, in other embodiments of the present application, the electrical connection points between the conductive portion 22 and the first end wall 12111 do not necessarily extend along the length or width of the first end wall 12111, but may be, for example, a plurality of discretely placed points. For example, the conductive portion 22 has a plurality of spaced portions that are welded to the first end wall 12111, and such a description is omitted here.

[0157] When Figure 13 is combined, in some embodiments of the present application, when the conductive portion 22 is electrically connected to the first end wall 12111, a first recessed groove 12112 can be provided in the first end wall 12111, and the direction of settlement of the first recessed groove 12112 is in a direction away from the active material coated portion 21. At least a portion of the location where the conductive portion 22 is electrically connected to the first end wall 12111 is located within the first recessed groove 12112. Exemplarily, at least a portion of the conductive portion 22 is provided within the first recessed groove 12112 and is connected to a portion of the first end wall 12111 that defines the first recessed groove 12112.

[0158] In the above proposed technology, on the one hand, the first recessed groove 12112 can be used to pre-position and limit the position of the conductive part 22 to the electrical connection position, which is advantageous not only for accurately aligning the position and achieving electrical connection, thereby improving production efficiency, but also for improving the stability and reliability of the conductive part 22 and ensuring the stability and reliability of the charging and discharging process of the battery cell 10. On the other hand, by installing the first recessed groove 12112 in the first end wall 12111, the local wall thickness of the first end wall 12111 can be locally reduced, which is advantageous not only for welding, but also for reducing the weight of the first pole column 12 and improving the gravimetric energy density of the battery cell 10.

[0159] In some selective embodiments, a portion of the conductive portion 22 is fitted in close contact with the shape of the first side wall 12113. For example, if the first side wall 12113 is curved, the portion of the conductive portion 22 is also curved and can be fitted in close contact with the first side wall 12113. The electrical connection between the conductive portion 22 and the first side wall 12113 may be made at the close contact position, such that the electrical connection position extends along the first side wall 12113. This increases the electrical connection area and improves the reliability and stability of the electrical connection.

[0160] Of course, the present invention is not limited to these, and in other embodiments of the present application, the locations where the conductive portion 22 is electrically connected to the first side wall 12113 do not have to extend along the first side wall 12113, but may be, for example, a plurality of discretely placed points, for example the conductive portion 22 has a plurality of portions that are spaced apart and each welded to the first side wall 12113, which will not be described here.

[0161] It should be explained that there is no limit to the number of first side walls 12113, and may be determined according to the shape of the first receiving groove 12110, provided that one end of each first side wall 12113 away 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 circular or elliptical, and there is one first side wall 12113, which is formed in a ring and installed around the periphery of the first end wall 12111. Also for example, if the cross-sectional shape of the first receiving groove 12110 is rectangular or oval, the first end wall 12111 is rectangular or oval, and there are four first side walls 12113, each connected to one of the four sides of the first end wall 12111.

[0162] Furthermore, it should be explained that the first accommodating groove 12110 is not limited to being defined by a first end wall 12111 and a first side wall 12113. For example, in some embodiments, the first end wall 12111 may not be present. In that case, the first accommodating groove 12110 can be defined by a plurality of first side walls 12113, with the ends of each first side wall 12113 that are away from the groove opening of the first accommodating groove 12110 converging. In this case, the conductive portion 22 is electrically connected to the first side walls 12113, and it is sufficient that the charging and discharging process of the battery cell 10 is ensured to proceed normally.

[0163] Furthermore, it should be explained that in other embodiments of the present application, the electrical connection point between the conductive portion 22 and the first pole post 12 does not have to be located within the first housing groove 12110. For example, the position where the conductive portion 22 is electrically connected to the first pole post 12 may also be located on the inner end face 122 of the pole post.

[0164] Combining Figures 12 and 13, in the embodiment of the present invention, the first pole column 12 may also be provided with a first groove 126 located on the side away from the active material coated portion 21 of the first pole column 12, if necessary. That is, the surface of the first pole column 12 on the side away from the active material coated portion 21 is the outer end surface 123 of the pole column, and the groove opening of the first groove 126 is formed on the outer end surface 123 of the pole column.

[0165] As can be understood, the first groove 126 is a groove body, and the groove body is a groove-like structure having a certain depth. Furthermore, when the first pole column 12 is installed on the upper end wall of the casing 11 and the outer end surface 123 of the pole column is the upper surface of the first pole column 12, the first groove 126 is formed as a groove with an opening that faces upward and a groove wall that is recessed downward. Also, for example, when the first pole column 12 is installed on the lower end wall of the casing 11 and the outer end surface 123 of the pole column is the lower surface of the first pole column 12, the first groove 126 is formed as a groove with an opening that faces downward and a groove wall that is recessed upward.

[0166] In the above proposed technology, on the one hand, the weight of the first pole column 12 can be further reduced by installing the first groove 126 on the first pole column 12, thereby improving the gravimetric energy density of the battery cell 10 and the battery 100. On the other hand, the first groove 126 is located on the outside of the first pole column 12, that is, it opens toward the side away from the inside of the casing 11 of the first pole column 12, and the first groove 126 can be used to accommodate or attach structural members electrically connected to each battery cell 10 in the battery 100, thereby making full use of the space inside the first pole column 12 and improving the space utilization rate and volumetric energy density of the battery 100.

[0167] Furthermore, the first pole column 12 has both a first housing groove 12110 and a first recessed groove 126, the first recessed groove 126 is located on the side of the first housing groove 12110 away from the active material coated portion 21, and the first recessed groove 126 is open in a direction away from the first housing groove 12110, thereby facilitating laser welding of the conductive portion 22 and the first end wall 12111 via the first recessed groove 126 from the outside of the first pole column 12, i.e., from the side of the first pole column 12 away from the active material coated portion 21, thus easily realizing an electrical connection between the conductive portion 22 and the first pole column 12 by external welding. In other words, the above structure makes it easy to externally weld the first pole column 12 and the conductive portion 22 via the first recessed groove 126, facilitating the processing and manufacturing of the battery cell 10 and saving processing and manufacturing costs.

[0168] Furthermore, in order to conveniently and effectively weld the conductive portion 22 and the groove wall of the first housing groove 12110 via the first recessed groove 126 and to improve the welding reliability between the conductive portion 22 and the groove wall of the first housing groove 12110, in the embodiment of the present application, the portion between the first recessed groove 126 and the first housing groove 12110 can be laser-welded to the conductive portion 22, that is, the gap portion 127 shown in Figure 13 of the drawings is laser-welded to the conductive portion 22. The gap portion 127 between the first groove 126 and the first housing groove 12110 of the first pole column 12 is thin in thickness, and the gap portion 127 separates the first groove 126 and the first housing groove 12110. The wall surface of the gap portion 127 on the side close to the active material coated portion 21 can be the first end wall 12111. When it is necessary to weld the conductive portion 22 to the first end wall 12111, the relatively thin thickness of the gap portion 127 is advantageous for welding the conductive portion 22 to the first end wall 12111 via the first groove 126, improving the convenience and reliability of welding.

[0169] In some embodiments, the first housing groove 12110 can be configured in a shape where the length of the cross-section is greater than the width, such as a rectangle, ellipse, or oblong shape. The weld mark formed by welding the conductive part 22 and the first pole column 12 may be a long weld mark parallel to the length direction of the first housing groove 12110, thereby improving the reliability of the welding and improving the current flow performance. For example, when the conductive part 22 and the first end wall 12111 are welded to form a long weld mark, the width of the weld mark can be 6 mm or more, and the distance between the weld mark and the first side wall 12113 can be 1 mm or more, in order to ensure the convenience and reliability of the welding while maintaining the current flow capability of the battery cell 10.

[0170] Combining Figure 12, the casing assembly 1 may further include a groove cover 7 provided on the first pole column 12 and sealing the groove opening of the first recessed groove 126.

[0171] In the above proposed technology, by installing a groove cover 7 that seals the first groove 126, the first pole post 12 can achieve indirect electrical connection with the bus member via the groove cover 7. Depending on the position and structure of the groove cover 7, the electrical connection between the groove cover 7 and the bus member becomes more convenient and the electrical connection area becomes larger. As a result, by installing the groove cover 7, the electrical connection of adjacent battery cells 10 within the battery 100 can be facilitated, and since the electrical connection position between the battery cells 10 is located at the groove cover 7, the electrical connection position between the conductive part 22 and the first pole post 12 can be separated by the first groove 126, reducing interference between the two and further improving the stability and reliability of the battery cells 10.

[0172] It should be noted that the specific configuration of the battery core assembly 2 in the embodiments of the present application is not limited and may include, for example, the following two embodiments, but is not limited to them.

[0173] When Figures 13 and 14 are combined, in the first 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 is electrically connected to the current collector 211 and includes a tab portion 221 which includes a plurality of tab sheets 2211, the tab sheets 2211 which are electrically connected to the current collector 211 but have a structure in which active material is not coated, and can be formed by directly die-cutting the current collector 211, the plurality of tab sheets 2211 gather at a position close to the current collector 211 (i.e., gather in a direction that brings them closer to each other) to form a first convergence portion 2212, the plurality of tab sheets 2211 gather and connect at a position away from the current collector 211 to form a second convergence portion 2213, and the first convergence portion 2212 connects the second convergence portion 2213 and the active material coated portion 21. If the housing portion 121 has a first housing groove 12110, at least a portion of the second convergence portion 2213 can be housed within the first housing groove 12110.

[0174] In the above-described technical proposal, the multiple tab sheets 2211 simply come together (i.e., converge toward each other) when forming the first convergence portion 2212, but are not connected. However, when forming the second convergence portion 2213, the multiple tab sheets 2211 not only come together but are also connected to form an integrated structure. For example, the multiple tab sheets 2211 can be connected to form an integrated plate-like structure by welding (e.g., ultrasonic welding) to form the second convergence portion 2213. However, this invention is not limited to these methods. Furthermore, the multiple tab sheets 2211 can be brought together and connected by methods such as bonding with a conductive adhesive to form the second convergence portion 2213, and such methods are not described here.

[0175] To explain further, in the embodiment of the present application, 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 be converged are stacked and ultrasonically tack-welded to form a second convergence portion 2213 of the positive electrode, thereby reducing the interlayer gap and forming a plate-like structure with a certain degree of rigidity from the multiple soft positive electrode tab sheets 2211. Similarly, the negative electrode tab sheets 2211 that need to be converged are stacked and ultrasonically tack-welded to form a second convergence portion 2213 of the negative electrode, thereby reducing the interlayer gap and forming a plate-like structure with a certain degree of rigidity from the multiple soft negative electrode tab sheets 2211.

[0176] In the above proposed technology, the statement "multiple tab sheets 2211 gather at a position close to the current collector 211 to form a first convergence section 2212, and multiple tab sheets 2211 gather at a position away from the current collector 211 and connect to form a second convergence section 2213" means that along the extending direction of the tab sheets 2211, the first convergence section 2212 and the second convergence section 2213 are installed sequentially in the direction away from the current collector 211, and the specific positions of the first convergence section 2212 and the second convergence section 2213 are not limited; that is, it is not required how close the first convergence section 2212 is to the current collector 211 or how far the second convergence section 2213 is from the current collector 211. In some selective examples, the current collector 211 and the tab sheet 2211 may be a single integrated component, for example, an integrally molded aluminum foil with respect to the positive electrode piece, or an integrally molded copper foil with respect to the negative electrode piece.

[0177] In the above proposed technology, the tab portion 221 includes a second convergence portion 2213 formed by the aggregation and connection of multiple tab sheets 2211. Therefore, at least a portion of the second convergence portion 2213 is housed in the first housing groove 12110, facilitating the connection between the conductive portion 22 and the first pole column 12, allowing for full utilization of the space of the first pole column 12, and improving the volumetric energy density of the battery cell 10.

[0178] Combining Figures 12 to 14, in the first embodiment, at least a portion of the first convergence portion 2212 is housed in the first housing groove 12110. In the above technical proposal, at least a portion of the first convergence portion 2212 and at least a portion of the second convergence portion 2213 of the tab portion 221 are both housed in the first housing groove 12110, thereby making better use of the space within the first pole column 12 to accommodate a larger active material coated 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 further 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 coated portion 21.

[0179] In this embodiment, the second convergence portion 2213 is electrically connected to the first pole column 12 directly or indirectly. For example, as shown in Figure 12, if the second convergence portion 2213 is directly electrically connected to the first pole column 12, for example, if the second convergence portion 2213 is welded to the first pole column 12 (e.g., laser welded), the configuration of the battery core assembly 2 can be simplified, the number of parts can be reduced, the assembly process can be simplified, and the assembly efficiency can be improved. The method and location of the direct electrical connection between the second convergence portion 2213 and the first pole column 12 are not limited. For example, the electrical connection point between the second convergence portion 2213 and the first pole column 12 may be located on the first end wall 12111 and / or the first side wall 12113, and furthermore, the electrical connection point between the second convergence portion 2213 and the first end wall 12111 may extend along the length or width direction of the first end wall 12111, and furthermore, the first end wall 12111 may have a first recessed groove 12112, and the electrical connection point between the second convergence portion 2213 and the first end wall 12111 may be located within the first recessed groove 12112, and so on. For corresponding technical effects, please refer to the description of the above embodiment, which will be omitted here.

[0180] In an optional technical configuration, the conductive portion 22 may be further fitted with an adapter sheet 222 as needed, in which case the second convergence portion 2213 is indirectly electrically connected to the first pole 12. Specifically, combining Figure 13, when the conductive portion 22 includes an adapter sheet 222, the adapter sheet 222 is connected to the second convergence portion 2213, and the conductive portion 22 is electrically connected to the first pole 12 via the adapter sheet 222. In this case, at least a portion of the adapter sheet 222 is housed in the first housing groove 12110, and in this example, at least a portion of the second convergence portion 2213 is also housed in the first housing groove 12110, although the first convergence portion 2212 may or may not be housed in the first housing groove 12110.

[0181] In the above proposed technology, the active material coated portion 21 can achieve electrical connection with the first pole column 12 via the first convergence portion 2212, the second convergence portion 2213, and the adapter sheet 222, respectively. The electrical connection position between the conductive portion 22 and the first pole column 12 is located on the adapter sheet 222, and the electrical connection can be achieved, for example, by welding (e.g., laser welding) between the adapter sheet 222 and the first pole column 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).

[0182] In the above proposed technology, by housing at least a portion of the second convergence portion 2213 and at least a portion of the adapter sheet 222 within the first housing groove 12110, the space within the first pole column 12 can be utilized more effectively, and the space occupied by the conductive portion 22 within the casing 11 can be further reduced, thereby improving the volumetric energy density of the battery cell 10. On the other hand, if at least a portion of the first convergence portion 2212, at least a portion of the second convergence portion 2213, and at least a portion of the adapter sheet 222 are all housed within the first housing groove 12110, the space within the first pole column 12 can be utilized more effectively, and the space occupied by the conductive portion 22 within the casing 11 can be reduced more effectively, thereby further improving the volumetric energy density of the battery cell 10.

[0183] On the other hand, by using the adapter sheet 222 to achieve an indirect electrical connection between the second convergence section 2213 and the first pole column 12, the adapter sheet 222 can be welded to the first pole column 12 using the portion that avoids the second convergence section 2213. This ensures that the adapter sheet 222 and the first pole column 12 are securely welded together, reducing the risk of welding cracks and further improving the reliability and stability of the battery cell 10. At the same time, electrically connecting the first pole column 12 and the tab sheet 2211 via the adapter sheet 222 also simplifies the structure of the tab sheet 2211.

[0184] Here, the method and location of direct electrical connection between the adapter sheet 222 and the first pole column 12 are not limited. For example, the adapter sheet 222 and the first pole column 12 are electrically connected by welding. For example, the electrical connection location between the adapter sheet 222 and the first pole column 12 may be located on the first end wall 12111 and / or the first side wall 12113, and furthermore, the electrical connection location 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, and furthermore, the first end wall 12111 may have a first recessed groove 12112, and the electrical connection location between the adapter sheet 222 and the first end wall 12111 may be located within the first recessed groove 12112, and so on. For corresponding technical effects, please refer to the description of the above embodiment, which will be omitted here. When the electrical connection point between the adapter sheet 222 and the first pole column 12 is located at the first end wall 12111 and / or the first side wall 12113, at least a portion of the adapter sheet 222 is housed in the first housing groove 12110, thereby simplifying the structure of the adapter sheet 222, reducing redundancy, and lowering costs.

[0185] Combining Figures 13 and 14, in the second embodiment, the active material coated portion 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211, the conductive portion 22 includes a tab portion 221 and an adapter sheet 222, the tab portion 221 includes a plurality of tab sheets 2211 electrically connected to the current collector 211, the plurality of tab sheets 2211 gather at a position close to the current collector 211 to form a first convergence portion 2212, the plurality of tab sheets 2211 gather and connect at a position away from the current collector 211 to form a second convergence portion 2213, and the adapter sheet 222 is electrically connected to the second convergence portion 2213. If the housing portion 121 has a first housing groove 12110, at least a portion of the adapter sheet 222 can be housed in the first housing groove 12110 and electrically connected to the first pole column 12.

[0186] In the above-described technical proposal, the second embodiment, compared to the technical proposal including the adapter sheet 222 of the first embodiment, has at least a portion of the adapter sheet 222 housed in the first housing groove 12110. However, the relative position of the tab portion 221 and the first housing groove 12110 is not restricted. That is, at least a portion of the tab portion 221 can be housed in the first housing groove 12110, or the tab portion 221 can be located entirely outside the first housing groove 12110. This allows for the fulfillment of different structural design requirements.

[0187] In the above proposed technology, by housing at least a portion of the adapter sheet 222 within the first housing groove 12110, the adapter sheet 222 can occupy space within the first pole column 12. This reduces the space occupied by the adapter sheet 222 within the casing 11, thereby accommodating a larger active material coating portion 21 and improving the volumetric energy density of the battery cell 10. Furthermore, it reduces the probability of a short circuit between the adapter sheet 222 and the active material coating portion 21, thereby improving the stability and reliability of the battery cell 10 and reducing the risk of a short circuit in the battery core assembly 2.

[0188] Furthermore, by using the adapter sheet 222 to achieve an indirect electrical connection between the second convergence section 2213 and the first pole column 12, the adapter sheet 222 can be welded to the first pole column 12 using the portion of the adapter sheet 222 that avoids the second convergence section 2213. This ensures a secure weld between the adapter sheet 222 and the first pole column 12, reducing the risk of welding cracks and further improving the reliability and stability of the battery cell 10. At the same time, electrically connecting the first pole column 12 and the tab sheet 2211 via the adapter sheet 222 simplifies the structure of the tab sheet 2211.

[0189] For example, in some selective embodiments, such as Embodiment 1 above or the third embodiment below, when the second convergence portion 2213 is directly electrically connected to the first pole column 12, the conductive portion 22 may consist only of the positive and negative electrode tabs in each electrode assembly 2a. For example, in some other embodiments, such as Embodiment 1 or Embodiment 2 above, or the third or fourth embodiment below, when the second convergence portion 2213 and the first pole column 12 are indirectly electrically connected via an adapter sheet 222, the conductive portion 22 may consist of the positive and negative electrode tabs in each electrode assembly 2a and each adapter sheet 222.

[0190] In some embodiments, when the battery core assembly 2 includes two electrode assemblies 2a, the tab sheets 2211 of the two electrode assemblies 2a can converge together, and the convergence position is centrally located between the two electrode assemblies 2a, forming a symmetrically converged configuration (for example, as shown in Figures 14 and 15(a)). In some other embodiments, when the tab sheets 2211 of the two electrode assemblies 2a converge together, the convergence position may be close to one electrode assembly 2a, forming an asymmetrically converged configuration (for example, as shown in Figures 15(b) and 15(c)). Furthermore, the electrode assembly 2a may be in a configuration with the entire tab extended (for example, as shown in Figure 15(a)) or in a configuration with half the tab extended (for example, as shown in Figures 14, 15(b), and 15(c)).

[0191] Of course, this invention is not limited to this, and the tab sheets 2211 of the same polarity in the two electrode assemblies 2a do not have to converge together. For example, the tab sheets 2211 of each electrode assembly 2a may converge independently at the positive and negative electrodes, that is, the positive electrode tab of one electrode assembly 2a may converge independently, and the positive electrode tab of the other electrode assembly 2a may also converge independently, but the explanation of this is omitted here.

[0192] It should be noted that the housing portion 121 in the embodiment of the present application is not necessarily limited to having a first housing groove 12110, and several other optional embodiments are shown below.

[0193] Exemplary, combining Figure 16, in some embodiments of the present application, the housing portion 121 may be configured to include a second housing groove 12120, the surface of the first pole column 12 away from the active material coated portion 21 being the pole column outer end face 123, the groove opening of the second housing groove 12120 being formed on the pole column outer end face 123, the second housing groove 12120 communicating with the interior of the casing 11 via the first through hole 12130, the conductive portion 22 being drilled in the first through hole 12130 and at least a portion of it being housed in the second housing groove 12120.

[0194] As can be understood, the second accommodating groove 12120 is a groove body, and the groove body is a groove-shaped structure having a certain depth. For example, if the first pole column 12 is installed on the upper end wall of the casing 11 and the outer end surface 123 of the pole column is the upper surface of the first pole column 12, the second accommodating groove 12120 is formed as an accommodating groove with a groove opening that faces upward and a groove wall that is recessed downward. Alternatively, if the first pole column 12 is installed on the lower end wall of the casing 11 and the outer end surface 123 of the pole column is the lower surface of the first pole column 12, the second accommodating groove 12120 is formed as an accommodating groove with a groove opening that faces downward and a groove wall that is recessed upward.

[0195] In the above proposed technology, when Figure 16 is combined, on the one hand, by installing the second housing groove 12120 on the first pole column 12, the weight of the first pole column 12 can be reduced to some extent, thereby improving the gravimetric energy density of the battery cell 10 and the battery 100. On the other hand, since the groove opening of the second housing groove 12120 is formed on the outer end surface 123 of the pole column, and the outer end surface 123 is the surface of the first pole column 12 that is away from the active material coated portion 21, the second housing groove 12120 can be opened in the direction away from the active material coated portion 21. In this way, when at least a part of the conductive portion 22 is housed in the second housing groove 12120, the groove opening of the second housing groove 12120 makes it easy to house and organize the conductive portion 22, and the groove opening of the second housing groove 12120 makes it easy to perform electrical connection operations between the conductive portion 22 and the first pole column 12, thereby reducing the difficulty of producing the battery cell 10 and improving the production efficiency of the battery cell 10.

[0196] At the same time, since the second housing groove 12120 can pass through the first through hole 12130 and communicate with the inside of the casing 11, the second housing groove 12120 may also be used as a buffer and temporary storage structure for the electrolyte, allowing the casing 11 to accommodate more electrolyte. As electrolyte is consumed during the charging and discharging process of the battery cell 10, having more electrolyte can extend the service life of the battery cell 10. Furthermore, since the second housing groove 12120 passes through the first through hole 12130 and communicates with the inside of the casing 11, the second housing groove 12120 can also be used as a gas containment and buffer structure for gases generated inside the battery core assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

[0197] As should be explained, if the housing portion 121 has a second housing groove 12120, and the conductive portion 22 is drilled in the first through hole 12130 and at least a part of it is housed in the second housing groove 12120, then the electrical connection position between the conductive portion 22 and the first pole column 12 is not limited.

[0198] For example, if the conductive portion 22 is drilled in the first through hole 12130 and at least a portion of it is housed in the second housing groove 12120, then in the embodiment of the present application, the electrical connection position between the conductive portion 22 and the first pole post 12 is located at the hole wall of the first through hole 12130 formed by the first pole post 12.

[0199] In the above proposed technology, by setting the electrical connection position between the conductive part 22 and the first pole post 12 on the wall of the first through hole 12130, the electrical connection operation between the conductive part 22 and the first pole post 12 can be easily performed via the second accommodating groove 12120. Furthermore, when the electrical connection area between the conductive part 22 and the first pole post 12 is relatively large, the electrical connection between the conductive part 22 and the first pole post 12 can be used to seal the first through hole 12130, thereby saving sealing costs and reducing electrolyte leakage, thus saving on sealing components.

[0200] Specifically, the conductive part 22 and the hole wall of the first through-hole 12130 can be welded at the position where the first through-hole 12130 and the second housing groove 12120 are connected, facilitating operation. Furthermore, by controlling the weld marks, the first through-hole 12130 can be sealed using the weld marks and the conductive part 22, thereby improving the problem of electrolyte leakage from the casing 11 through the first through-hole 12130.

[0201] More specifically, if the conductive portion 22 is drilled in the first through-hole 12130 and at least a portion of it is housed in the second housing groove 12120, in some other embodiments of the present invention, the electrical connection position between the conductive portion 22 and the first pole post 12 may further be located at the groove wall of the second housing groove 12120 formed by the first pole post 12. This facilitates the electrical connection operation and improves the problem of conductive particles produced by welding entering the casing 11 and causing short circuits, for example, when the conductive portion 22 is welded to the groove wall of the second housing groove 12120 formed by the first pole post 12.

[0202] Specifically, combining Figures 16 and 17, the first pole column 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 active material coated portion 21, the second end wall 12121 and the second side wall 12123 surround each other to form a second housing groove 12120, the first through hole 12130 is opened in the second end wall 12121, and the position where the conductive portion 22 is electrically connected to the first pole column 12 is located in the second end wall 12121 and / or the second side wall 12123.

[0203] More specifically, since an electrical connection can be formed between the conductive part 22 and the first pole column 12 by welding, the welding position is the electrical connection position between the conductive part 22 and the first pole column 12. In other embodiments of the present invention, the conductive part 22 and the first pole column 12 can be electrically connected by other methods instead of welding, such as by installing a conductive adhesive or a conductive pin, and such methods will not be described here.

[0204] For the sake of simplicity, the following description will assume that the conductive portion 22 and the first pole column 12 are electrically connected by welding, and that the welding position is the electrical connection position between the conductive portion 22 and the first pole column 12. For example, in some embodiments, the electrical connection position between the conductive portion 22 and the first pole column 12 is located at the second end wall 12121 and / or the second side wall 12123, and the conductive portion 22 may be welded to at least one of the second end wall 12121 and the second side wall 12123.

[0205] In the above proposed technology, by setting the electrical connection point between the conductive part 22 and the first pole column 12 on at least one of the second end wall 12121 and the second side wall 12123, the second housing groove 12120 not only serves to accommodate at least a portion of the conductive part 22, but the groove wall of the second housing groove 12120 further serves to realize an electrical connection with the conductive part 22, thereby simplifying the structure of the first pole column 12 and facilitating the processing of the first pole column 12. Furthermore, since the first through hole 12130 is opened in the second end wall 12121, the conductive part 22 can extend to the second housing groove 12120 through the first through hole 12130, simplifying the structure of the conductive part 22, reducing the redundancy of the conductive part 22, and reducing the cost of the conductive part 22. Furthermore, the opening direction of the groove opening of the second housing groove 12120 facilitates the electrical connection operation between the conductive part 22 and the groove wall of the second housing groove 12120 via the groove opening of the second housing groove 12120, reducing the difficulty of electrical connection. Moreover, by utilizing the groove wall of the second housing groove 12120 to achieve electrical connection with the conductive part 22, the electrical connection area between the conductive part 22 and the first pole column 12 can be set relatively large, improving the reliability and stability of the electrical connection and further improving the performance of the battery cell 10.

[0206] Furthermore, since the electrical connection position between the conductive part 22 and the first pole post 12 is located within the second housing groove 12120, it is possible to avoid the electrical connection position protruding outside the first pole post 12 and occupying space other than the first pole post 12. In addition, the first pole post 12 is protected at the electrical connection position, thereby improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole post 12.

[0207] When Figures 16 and 17 are combined, in some embodiments, the local shape of the conductive portion 22 matches the local shape of the second end wall 12121 and is installed in close contact to achieve electrical connection, and the position where the conductive portion 22 is electrically connected to 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 placed in close contact with the second end wall 12121, and the contact portion may be electrically connected, for example, by welding. This increases the electrical connection area and improves the reliability and stability of the electrical connection.

[0208] It should be noted that the shape of the second end wall 12121 is not limited and can be, for example, a flat plate or an arc-shaped plate. Here, if the second end wall 12121 is a flat plate structure, it is positioned at an angle with the axial direction R of the first pole column 12. For example, it may be a flat plate structure perpendicular to the axial direction R of the first pole column 12, or it may be an inclined flat plate structure not perpendicular to the axial direction R of the first pole column 12, but the direction of inclination is not limited.

[0209] For example, when Figures 16 and 17 are combined, if the second end wall 12121 has a flat plate structure, the angle θ between the second end wall 12121 and the axial direction R of the first pole column 12 is equal to 90°, that is, the second end wall 12121 and the active material coated portion 21 are equally spaced along the direction from the first through hole 12130 to the second side wall 12123. This facilitates welding between the conductive portion 22 and the second end wall 12121.

[0210] Furthermore, for example, when Figure 18 is combined, the angle θ between the second end wall 12121 and the axial R of the first pole column 12 is greater than 90°, meaning that the second end wall 12121 extends obliquely along the direction from the first through hole 12130 to the second side wall 12123, facing in a direction close to the active material coated portion 21. This allows the extension distance of the conductive portion 22 along the second end wall 12121 to be increased, thereby improving the reliability of the electrical connection. For example, the angle θ between the second end wall 12121 and the axial direction R of the first pole column 12 is 90° to 145°, and may be, for example, 100°, 110°, 120°, 130°, 140°, etc. This makes it easier to process the second end wall 12121 and to easily connect it electrically to the conductive part 22, while also allowing the conductive part 22 to be housed using the space inside the first pole column 12 relatively sufficiently.

[0211] Furthermore, for example, when Figure 19 is combined, the angle θ between the second end wall 12121 and the axial R of the first pole column 12 is less than 90°, that is, the second end wall 12121 extends obliquely in the direction 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 extension distance of the conductive portion 22 along the second end wall 12121 to be increased, improving the reliability of the electrical connection. Exemplarily, the angle θ between the second end wall 12121 and the axial R of the first pole column 12 is 45° to 90°, and may be, for example, 50°, 60°, 70°, 80°, etc. This makes it easier to process the second end wall 12121 and to easily connect it to the conductive portion 22, while also allowing the conductive portion 22 to be housed using the space within the first pole column 12 relatively sufficiently.

[0212] Of course, the present invention is not limited to these, and in other embodiments of the present application, the locations where the conductive portion 22 is electrically connected to the second end wall 12121 do not have to extend along the length or width of the second end wall 12121, but may be a plurality of discretely placed points. For example, the conductive portion 22 has a plurality of parts that are spaced apart and each is welded to the second end wall 12121, but such a description is omitted here.

[0213] When Figure 17 is reassembled, regardless of the specific value of the angle θ between the second end wall 12121 and the axial radius R of the first pole column 12, in the embodiment of the present application, when the conductive portion 22 is electrically connected to the second end wall 12121, the second recessed groove 12122 can be installed in the second end wall 12121 as needed, and the second recessed groove 12122 is a recess formed by the local portion of the second end wall 12121 sinking at one end close to the active material coated 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 recessed groove 12122.

[0214] In the above-described technical proposal, the portion of the conductive part 22 located within the second recessed groove 12122 is installed to conform to the shape of the second recessed groove 12122, is installed in close contact with it, and is electrically connected. This allows for pre-positioning and positional restriction of the electrical connection position of the conductive part 22 using the second recessed groove 12122, enabling precise positioning and electrical connection, which is advantageous for improving production efficiency and enhances the stability and reliability of the electrical connection position, thereby guaranteeing the reliability and stability of the charging and discharging operations of the battery cell 10.

[0215] It should be explained that in the embodiment of the present application, a portion of the conductive portion 22 can conform to the shape of the second side wall 12123 and be installed in close contact. For example, if the second side wall 12123 is curved, a portion of the conductive portion 22 may also be curved and be in close contact with the second side wall 12123, and the electrical connection between the conductive portion 22 and the second side wall 12123 may be made in a close position such that the electrical connection position extends along the second side wall 12123. This increases the electrical connection area and improves the reliability and stability of the electrical connection.

[0216] It should be explained that in other embodiments of the present application, the electrical connection points between the conductive portion 22 and the second side wall 12123 do 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 portions that are welded to the second side wall 12123, and such a description is omitted here.

[0217] As can be understood, there is no limit to the number of second side walls 12123, and may be determined according to the shape of the second receiving groove 12120, provided that one end of each second side wall 12123 away 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 circular or elliptical, and there is one second side wall 12123, which is formed in a ring and installed around the periphery of the second end wall 12121. Also for example, if the cross-sectional shape of the second receiving groove 12120 is rectangular or oval, the second end wall 12121 is rectangular or oval, and there are four second side walls 12123, each connected to one of the four sides of the second end wall 12121.

[0218] Furthermore, it should be explained that the second accommodating groove 12120 is not limited to a configuration defined by a second end wall 12121 and a second side wall 12123. For example, in some embodiments, when Figure 20 is combined, each end of the second side wall 12123 that moves away from the groove opening of the second accommodating groove 12120 extends to the first through hole 12130. Thus, the second accommodating groove 12120 is defined solely by a plurality of second side walls 12123, in which case the conductive portion 22 can be electrically connected to the second side walls 12123.

[0219] In some embodiments, when Figure 32 is combined, the housing portion 121 can have both a third housing groove 12140 and a second housing groove 12120, the second housing groove 12120 being located on the side of the third housing groove 12140 away from the active material coating portion 21, the groove opening of the third housing groove 12140 being formed on the inner end face 122 of the pole column 12 on the side of the first pole column 12 close to the active material coating portion 21, and the groove opening of the second housing groove 12120 being located on the outer side of the pole column 12 away from the active material coating portion 21 The third housing groove 12140 and the second housing groove 12120 are formed on the end face 123 and communicate with each other via the first through hole 12130. In this case, a portion of the conductive portion 22 is located in the third housing groove 12140, and at the same time, the conductive portion 22 is further drilled in the first through hole 12130, and the other portion of the conductive portion 22 is located in the second housing groove 12120. This allows for relatively sufficient use of the space within the first pole column 12 and reduces the space occupied by the conductive portion 22 within the casing 11.

[0220] It should be explained that when the conductive part 22 is connected to the second end wall 12121 or the second side wall 12123 by laser welding, as shown in Figure 20, setting the angle β between the part of the conductive part 22 used for welding and the axis of the first through hole 12130 to be greater than 5° reduces the problem of the laser entering the casing 11 through the first through hole 12130 and is also advantageous for the welding operation. Furthermore, when the angle β between the part of the conductive part 22 used for welding and the axis of the first through hole 12130 is close to 5°, an edge welding method can be adopted, and an overlap welding method can be adopted for the other parts.

[0221] When Figure 16 is reassembled, in the embodiment of the present application, the connection method between the first pole post 12 and the casing 11 is not limited, and may be, for example, welded or riveted. For example, when the two are fitted together by riveting, the casing 11 has a mounting hole 113, and the first pole post 12 is attached to the mounting hole 113 by riveting. Of course, when the two are fitted together by welding or other methods, the casing 11 may have a mounting hole 113, and the first pole post 12 is understood to be attached to the mounting hole 113.

[0222] Selectively, by combining Figure 16, the second housing groove 12120 may be installed corresponding to the position of the mounting hole 113. In other words, if the orthographic projection of the second housing groove 12120 lies within the orthographic projection range of the mounting hole 113 in the projection plane perpendicular to the axial R of the first pole column 12, the second housing groove 12120 has a relatively large depth, allowing it to accommodate more conductive parts 22, and consequently, the space occupied by the conductive parts 22 within the casing 11 can be reduced more significantly.

[0223] In some embodiments, when Figure 16 is combined, the casing 11 has a mounting hole 113, and when the first pole post 12 is mounted in the mounting hole 113, the depth H3 of the second housing groove 12120 is greater than or equal to the minimum distance H4 from the outer end face 123 of the pole post to the mounting hole 113 along the axial R of the first pole post 12.

[0224] It should be explained that the specific shape of the second receiving groove 12120 is not limited and may be regular or irregular in shape. For example, it may be a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a semi-elliptical groove with an elliptical cross-section and gradually changing cross-sectional dimensions. It should be explained that, as described herein, an oblong refers to a shape in which the two short sides of a rectangle, as shown by combining Figure 22(b), are replaced by curves that protrude outwards.

[0225] Therefore, the depth H3 of the second housing groove 12120 refers to the maximum depth of the second housing groove 12120 along the axial R of the first pole column 12. In the axial R of the first pole column 12, the depth H3 of the second housing groove 12120 is greater than or equal to the minimum distance H4 from the outer end face 123 of the pole column to the mounting hole 113. This allows for full utilization of the volume of the first pole column 12, and the second housing groove 12120 has a relatively large depth, which is advantageous for accommodating more conductive parts 22. Furthermore, it can further reduce the space occupied by the conductive parts 22 within the casing 11, further improve the energy density of the battery cell 10, and further reduce the redundancy of the conductive parts 22 within the casing 11. At the same time, because the second housing groove 12120 has a relatively large depth, it can accommodate gas generated in the battery core assembly 2, not only ensuring the reliability and stability of the battery cell 10, but also allowing for the accommodation of more electrolyte, thus ensuring the service life of the battery cell 10.

[0226] It should be explained that the volume of the second housing groove 12120 is not limited, and for example, in some specific examples, the volume of the second housing groove 12120 (referred to as the third volume V4) that can accommodate the conductive part 22 is 298 mm². 3 The second housing groove 12120 may have a relatively sufficient space for housing the conductive part 22 and facilitate welding the conductive part 22 to the first pole column 12. On the other hand, the third volume V4 of the second housing groove 12120 is 298 mm 3 If the third volume V4 of the second housing groove 12120 is less than 300 mm³, the capacity of the second housing groove 12120 to accommodate the conductive part 22 becomes relatively low, and welding the conductive part 22 to the first pole column 12 becomes difficult. For example, if the third volume V4 of the second housing groove 12120 is 300 mm³ 3 , 400mm 3 , 500mm 3 , 600mm 3 , 700mm 3 , 800mm 3 , 1000mm 3 You can also use these.

[0227] What needs to be explained is that the third volume V4 of the second housing groove 12120 is the difference between the total volume V5 of the second housing groove 12120 and the volume required for the second housing groove 12120 to accommodate other components other than the conductive part 22 (for example, the first cover plate 13 and the second cover plate 14 as described herein) (referred to as the fourth volume V6), i.e., V4 = V5 - V6. For example, in some specific examples, the total volume V5 of the second housing groove 12120 is 1400 mm 3 ~1500mm 3 Therefore, the second housing groove 12120 can have more space for housing the conductive part 22 and other components. For example, the total volume V5 of the second housing groove 12120 is 1420 mm 3 , 1440mm 3 , 1460mm 3 , 1480mm 3 , 1490mm 3 You can also use these.

[0228] In the embodiments of the present application, there are no restrictions on the shape of the first through-hole 12130, the number of the first through-hole 12130, or the relative positional relationship between the first through-hole 12130 and the second receiving groove 12120.

[0229] Exemplary, regarding the shape of the first through-hole 12130, combining Figures 21 and 22, in the embodiment of the present application, the shape of the first through-hole 12130 may be elongated so as to coincide with the sheet-like portion of the conductive portion 22, which is advantageous for the passage of the sheet-like portion of the conductive portion 22. At the same time, if the first through-hole 12130 is elongated, the second accommodating groove 12120 may be configured in a shape such as a rectangle, ellipse, or oblong, where the length of the cross-section is greater than the width. In this case, the length direction of the first through-hole 12130 can be set to coincide with the length direction of the cross-section of the second accommodating groove 12120, thereby making full use of the space. Furthermore, the weld marks formed by welding the conductive portion 22 and the first pole column 12 may be elongated weld marks parallel to the length direction of the first through-hole 12130 so as to improve the reliability of the welding and increase the current passage performance. For example, when the conductive portion 22 and the second end wall 12121 are welded to form a long weld, the width of the weld can be 6 mm or more, and the distance between the weld and the second side wall 12123 can be 1 mm or more, in order to ensure the convenience and reliability of the welding while maintaining the current passing capability of the battery cell 10.

[0230] Regarding the dimensions and number of the first through-holes 12130, in the embodiments of this application, the opening dimensions and specific positions of the first through-holes 12130 in the second housing groove 12120 are not limited, and the design can be carried out in accordance with the number of first through-holes 12130 that are opened. For example, the width of the first through-hole 12130 may be 2 mm or more, which is advantageous for the penetration of the conductive part 22. For example, if there is only one first through-hole 12130 opened in the second housing groove 12120, in some examples, combining Figures 21 and 22, the first through-hole 12130 may be positioned in the center of the second housing groove 12120, and in some other examples, combining Figure 23, the first through-hole 12130 may be positioned further offset from the center of the second housing groove 12120. For example, in some embodiments, by combining the features shown in Figure 23, 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 usable area of ​​the second end wall 12121 and increasing the welding area between the conductive portion 22 and the second end wall 12121.

[0231] As can be understood, after the conductive portion 22 passes through the first through-hole 12130, it is folded back so as to be in close contact with the second end wall 12121, but the direction of this folding is not limited. For example, if the first through-hole 12130 is centrally located relative to the second housing groove 12120, the conductive portion 22 can be folded back to face either side of the first through-hole 12130 after passing through it (combining Figure 21), thereby appropriately reducing the dimensions of the second housing groove 12120 and increasing the compactness and structural strength of the structure. Alternatively, the conductive portion 22 can be folded back to face the opposite side after passing through the first through-hole 12130 (combining Figure 24), thereby reducing the thickness of the welded area, reducing the heat input of the weld, and reducing problems such as particle scattering.

[0232] For example, if there are multiple first through-holes 12130 in the second housing groove 12120, the multiple first through-holes 12130 are arranged parallel or nearly parallel in their longitudinal direction so that the space can be fully utilized. In this case, the direction in which the conductive part 22 folds back after passing through the first through-hole 12130 can be set based on the relative positional relationship of the multiple first through-holes 12130. For example, if there are two first through-holes 12130 in the second housing groove 12120 and they are far apart from each other (see Figure 25), the two conductive parts 22 passing through the two first through-holes 12130 can fold back in a direction that brings them closer to each other, and if there are two first through-holes 12130 in the second housing groove 12120 and they are close to each other, the two conductive parts 22 passing through the two first through-holes 12130 can fold back in a direction that moves them away from each other.

[0233] As can be understood, if there are multiple first through holes 12130 opened in the second receiving groove 12120, the number of first pole posts 12 can be appropriately reduced, thereby reducing costs and simplifying the process.

[0234] Furthermore, in some embodiments, by combining Figures 23 and 24, the first through-hole 12130 can be positioned in the center relative to the active material coated section 21. However, the position of the first through-hole 12130 relative to the second accommodating groove 12120 is not limited; it may be in the center or offset. Since the first through-hole 12130 is positioned in the center relative to the active material coated section 21, the conductive section 22 can converge to correspond to the centerline position of the active material coated section 21.

[0235] In some embodiments, by combining the components shown in Figure 24, a sealing member 6 can be installed in the first through-hole 12130 to improve the problem of electrolyte leakage from the casing 11 through the first through-hole 12130. The material, shape, and connection configuration of the sealing member 6 to the first through-hole 12130 are not limited and can all be designed according to actual needs.

[0236] Combining Figures 26 and 27, in some embodiments of the present application, if the housing 121 has a second housing groove 12120 in any one of the above embodiments, the casing assembly 1 may optionally further include a first cover plate 13 that fits onto the first pole post 12 and seals the opening of the second housing groove 12120, the first cover plate 13 being electrically connected to the first pole post 12.

[0237] In the above proposed technology, by installing the first cover plate 13 so as to seal the groove opening of the second housing groove 12120, leakage of the electrolyte from the casing 11 through the groove opening of the second housing groove 12120 can be prevented. Furthermore, since the first cover plate 13 seals the groove opening of the second housing groove 12120 and is electrically connected to the first pole column 12, an indirect electrical connection between the first pole column 12 and the bus member can be easily realized using the first cover plate 13, and this is advantageous in increasing the connection area of ​​the electrical connection point and further reducing the resistance of the electrical connection point.

[0238] As long as the first cover plate 13 can be sealed to the groove opening of the second housing groove 12120, the fitting method and fitting position of the first cover plate 13 and the first pole post 12 are not limited. For example, in some embodiments, as shown in Figure 25, the first cover plate 13 may be welded to the first pole post 12. During processing, the conductive part 22 can first pass through the first through hole 12130 and be welded to the groove wall of the second housing groove 12120, and then the first cover plate 13 and the first pole post 12 can be welded together to seal the groove opening of the second housing groove 12120.

[0239] Furthermore, it should be noted that the specific configuration of the first cover plate 13 is not limited. For example, in several selective embodiments, when Figures 27 to 29 are combined, 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 first pole post 12, and the second conductive member 132 being fitted to and electrically connected to the first conductive member 131.

[0240] In the above proposed technology, by installing the first cover plate 13 in a composite form and installing the first conductive member 131 so as to be made of the same material as the first pole post 12, the electrical connection between the first conductive member 131 and the first pole post 12 is facilitated, and for example, the first conductive member 131 and the first pole post 12 can be reliably and stably connected by welding. Furthermore, because the second conductive member 132 and the first conductive member 131 are made of different materials, the second conductive member 132 can be used to easily electrically connect to bus members and the like that which are made of different materials than the first pole post 12, and for example, the second conductive member 132 and bus members made of the same material as the second conductive member 132 can be reliably and stably connected by welding.

[0241] For example, if the first pole column 12 is a negative pole column, and the first pole column 12 is a copper column and the bus member is an aluminum sheet, the first conductive member 131 can be installed on the copper material and the second conductive member 132 can be installed on the aluminum material. In this case, the first pole column 12 and the first conductive member 131 may be made of the same material and effectively welded together, and the second conductive member 132 and the bus member may be made of the same material and effectively welded together. This allows for effective indirect electrical connection between the first pole column 12 and the bus member via the first cover plate 13. Furthermore, the first pole column 12 and the first conductive member 131 are welded copper to copper, which provides excellent fluidity, reduces the likelihood of cracking, and improves the sealing effect of the welded area.

[0242] When FIGS. 27 to 29 are combined again, in some optional examples, the first conductive member 131 is located between the second receiving groove 12120 and the second conductive member 132. In the above technical solution, since the first conductive member 131 is located between the second receiving groove 12120 and the second conductive member 132, the second receiving groove 12120 and the second conductive member 132 can be separated. Thereby, when the electrolytic solution in the casing 11 enters the second receiving groove 12120 from the first through hole 12130, it is possible to avoid the electrolytic solution in that part contacting the second conductive member 132 by using the first conductive member 131, and the problem that the electrolytic solution corrodes the second conductive member 132 can be solved.

[0243] It should be noted that the fitting method of the first conductive member 131 and the second conductive member 132 is not limited. For example, in some embodiments, when FIGS. 27 to 29 are combined, the first conductive member 131 has a second concave groove 1311, and the second conductive member 132 is fitted into the second concave groove 1311. The groove opening of the second concave groove 1311 is formed on the surface of the first conductive member 131 on the side away from the second receiving groove 12120 so as to expose the second conductive member 132 from the groove opening of the second concave groove 1311. Alternatively, in other embodiments, the connection method between the first conductive member 131 and the second conductive member 132 may also be fastening connection, engagement, etc.

[0244] It should be further noted that the second conductive member 132 being "exposed" from the groove opening of the second concave groove 1311 means that the first conductive member 131 does not block the second conductive member 132 at the groove opening position of the second concave groove 1311, and it is not necessary for the second conductive member 132 to protrude from the groove opening of the second concave groove 1311. For example, the second conductive member 132 may be arranged flush with the surface of the first conductive member 131 on the side away from the second receiving groove 12120, and the second conductive member 132 may also protrude from the surface of the first conductive member 131 on the side away from the second receiving groove 12120.

[0245] In the above proposed technology, by fitting the second conductive member 132 into the first conductive member 131, the difficulty of assembling the first conductive member 131 and the second conductive member 132 can be reduced, improving the fitting stability and convenience of the first conductive member 131 and the second conductive member 132, as well as reducing the thickness of the first cover plate 13, thereby reducing the space occupied by the first cover plate 13 and improving the space utilization rate of the battery cell 10. On the other hand, since the second conductive member 132 can be exposed on the surface of the first conductive member 131 away from the second housing groove 12120 through the groove opening of the second recess 1311, it is advantageous for achieving electrical connection between the second conductive member 132 and the bus member outside the first pole post 12.

[0246] Furthermore, since the groove opening of the second groove 1311 is formed on the surface of the first conductive member 131 that is separated from the second housing groove 12120, it is suggested that the second groove 1311 opens in a direction away from the active material coated portion 21. For this reason, a portion defining the groove wall of the second groove 1311 of the first conductive member 131 is located between the second housing groove 12120 and the second conductive member 132. This separates the second housing groove 12120 and the second conductive member 132, preventing contact between the electrolyte that has entered the second groove 1311 and the second conductive member 132, and reducing electrolyte leakage.

[0247] Of course, in other embodiments, the first cover plate 13 does not have to be a composite form made of multiple materials. For example, in other embodiments of the present application, when combined with Figure 30, the first cover plate 13 can be installed in a non-composite form made entirely of the same material to fit, for example, a positive electrode column, but such a description will be omitted here.

[0248] When Figures 27 to 29 are combined again, in some embodiments, the first cover plate 13 is also fitted into the groove of the second housing groove 12120. In the above technical proposal, by fitting the first cover plate 13 into the second housing groove 12120, the difficulty of assembling the first cover plate 13 and the first pole post 12 can be reduced, the assembly stability, connection reliability and convenience of the first cover plate 13 and the first pole post 12 can be improved, and the space occupied by the first cover plate 13 other than the first pole post 12 can be reduced. Furthermore, since the first cover plate 13 is fitted into the groove of the second housing groove 12120, there can be a relatively sufficient space within the second housing groove 12120 to accommodate the conductive part 22.

[0249] Of course, in other embodiments of the present invention, the method of fitting the first cover plate 13 and the first pole post 12 is not limited to fitting them into the second housing groove 12120. The first cover plate 13 may also be placed outside the first pole post 12. That is, to facilitate fitting with the bus member of the battery 100, it may be directly covered at the groove opening of the second housing groove 12120, and this embodiment is not limited to this.

[0250] By combining Figures 27 to 29 again, selectively, in the embodiment of the present invention, at least a portion of the wall surface forming the groove opening of the second housing groove 12120 in the first pole column 12 is a guide slope 12126, and the guide slope 12126 is used to guide the first cover plate 13 to fit into the groove opening of the second housing groove 12120. In the above technical invention, by processing the wall surface of the groove opening of the second housing groove 12120 into a slope with a guiding function, the difficulty of assembling the first cover plate 13 and the second housing groove 12120 can be reduced, and the assembly efficiency of the first cover plate 13 and the second housing groove 12120 can be improved. Furthermore, when the first cover plate 13 is welded to the guide slope 12126, the area of ​​the weld can be increased, improving the reliability of the welded connection between the first cover plate 13 and the first pole column 12, and also improving the problem of the molten pool collapsing or the laser entering the first pole column 12 during welding.

[0251] Specifically, when Figures 27 to 29 are combined, the second housing groove 12120 includes the first groove step 12124 and the second groove step 12125 located on the side of the first groove step 12124 that is close to the outer end surface 123 of the pole column. Since the cross-sectional area of ​​the second groove step 12125 is larger than the cross-sectional area of ​​the first groove step 12124, by forming the second housing groove 12120 in a stepped groove shape and forming the connection position between the first groove step 12124 and the second groove step 12125 on a stepped surface 12127, the first cover plate 13 is fitted into the second housing groove 12120, specifically into the second groove step 12125, and is also supported by the stepped surface 12127.

[0252] In the above proposed technology, by installing the second housing groove 12120 in a stepped groove form, the first cover plate 13 can be stably fitted into the groove opening position of the second housing groove 12120, thereby improving the connection stability between the first cover plate 13 and the first pole column 12. Furthermore, by limiting the groove depth of the first groove step 12124, a relatively sufficient space can be provided within the second housing groove 12120 for housing the conductive part 22.

[0253] Furthermore, if the wall surface where the groove opening of the second housing groove 12120 of the first pole column 12 is formed is a guide slope 12126, the cross-sectional area of ​​the second groove step 12125 is set to gradually increase along the direction approaching the outer end surface 123 of the pole column, so that the side wall of the second groove step 12125 forms the guide slope 12126, thereby facilitating processing and easily and effectively satisfying the requirements for a guide.

[0254] By combining Figures 27 to 29 again, in the embodiment of the present invention, the first cover plate 13 can further have stress relief grooves 133 located in the outer peripheral region of the first cover plate 13 to assist the first cover plate 13 in relieving stress, if necessary. In the above technical proposal, by installing stress relief grooves 133 in the first cover plate 13, stress generated during the manufacturing process of the first cover plate 13 itself, or during the electrical connection process between the first cover plate 13 and the first pole column 12, is released in order to improve related problems such as deformation and damage that occur when the first cover plate 13 is subjected to stress.

[0255] Specifically, when the first cover plate 13 is fitted into the second housing groove 12120 and welded, the stress relief groove 133 releases the stress generated during welding, improves lateral heat conduction, and reduces the probability of the first cover plate 13 being damaged or deformed. At the same time, if the first cover plate 13 is a composite form including the first conductive member 131 and the second conductive member 132, by installing the stress relief groove 133 on the first conductive member 131 and positioning it in the outer peripheral region of the second conductive member 132, when the first conductive member 131 is fitted into the second housing groove 12120 and welded, the stress relief groove 133 releases the stress generated during welding, improves lateral heat conduction, and reduces the probability of the second conductive member 132 being damaged or deformed. Furthermore, when the second conductive member 132 and the first conductive member 131 are fitted together and welded, the stress relief groove 133 releases the stress generated during welding, improving lateral heat conduction and reducing the probability of deformation of the first conductive member 131 or the inability to fit the first conductive member 131 into the second housing groove 12120.

[0256] Combining Figures 30 to 31, in the embodiment of the present invention, a second cover plate 14 may be installed in the casing assembly 1 as needed, and the second cover plate 14 covers the outside of the conductive portion 22 located in the first through hole 12130 and the second housing groove 12120.

[0257] It should be explained that when the casing assembly 1 includes a second cover plate 14, the casing assembly 1 may also include a first cover plate 13, or it may not include a 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.

[0258] In the above proposed technology, at least a portion of the conductive portion 22 is located within the second housing groove 12120, the second cover plate 14 covers the conductive portion 22, and the second cover plate 14 further covers the first through hole 12130. This improves the problem of electrolyte overflowing from the first electrode post 12 when the electrolyte enters the second housing groove 12120 from the first through hole 12130, thereby improving the reliability of the battery cell 10.

[0259] For example, as shown in Figures 30 to 31, when a portion of the conductive part 22 is sandwiched between the second cover plate 14 and the second end wall 12121, a laser welding method can be used to weld the portion of the conductive part 22, the second cover plate 14, and the second end wall 12121 together, thereby improving the reliability of the connection between the first pole 12 and the conductive part 22. Furthermore, since the second cover plate 14 can press against the conductive part 22, the stability of the conductive part 22 being housed in the second housing groove 12120 can be improved by the second cover plate 14.

[0260] In the embodiment of the present application, the first pole column 12 may be an integrally molded pole column or a separately molded composite pole column. Combining Figures 30 and 31 again, for example, the first pole column 12 includes a first pole column portion 124 and a second pole column portion 125 made of different materials and electrically connected, the second pole column portion 125 is located on the side of the first pole column portion 124 away from the active material coated portion 21, the housing portion 121 is installed on the first pole column portion 124, or the housing portion 121 is installed on the first pole column portion 124 and the second pole column portion 125, and the conductive portion 22 is electrically connected to the first pole column portion 124.

[0261] In the above proposed technology, the first pole column 12 is installed in a composite form combining different materials, and the first pole column portion 124 located on the inside is used to house and fit with the conductive portion 22 and electrically connect it, while the second pole column portion 125 located on the outside is used to electrically connect with the bus member and the like. This is advantageous for assembling and electrically connecting the first pole column 12 and related members, reducing mutual interference between the electrical connection position between the first pole column 12 and the conductive portion 22 and the electrical connection position between the first pole column 12 and the bus member of the battery 100, thereby improving the reliability and stability of the battery cell 10.

[0262] For example, if the material of the conductive part 22 and the material of the bus member are different, the first pole column 124 can be installed so as to be made of the same material as the conductive part 22, and the second pole column 125 can be installed so as to be made of the same material as the bus member. This allows for welding of the second pole column 125 to the bus member and welding of the first pole column 124 to the conductive part 22, which is advantageous in improving the reliability and stability of the electrical connection between the conductive part 22 and the first pole column 12, and the reliability and stability of the electrical connection between the first pole column 12 and the bus member.

[0263] Furthermore, when the first pole 12 is in the composite form of the above embodiments and has the second receiving groove 12120 and the first through hole 12130 of any of the above embodiments, in some embodiments, the casing assembly 1 can simultaneously include the second cover plate 14 of any of the above embodiments. In this case, the second cover plate 14 is installed to have the same material as the first pole part 124, and the first pole part 124 and the second cover plate 14 can be electrically connected, thereby improving the reliability and stability of the electrical connection between the first pole part 124 and the second cover plate 14. For example, the first pole part 124 and the second cover plate 14 can be connected by welding.

[0264] For example, when FIGS. 30 and 31 are combined, if the first pole 12 is a negative pole, the first pole part 124 is made of copper, the second pole part 125 is made of aluminum, and the bus member is an aluminum sheet, the second cover plate 14 can be made of copper and the first cover plate 13 can be made of aluminum. In this case, by making the second cover plate 14 of the same material as the first pole part 124, effective welding can be achieved. By making the second pole part 125 of the same material as the first cover plate 13, effective welding can be achieved. By making the first cover plate 13 of the same material as the bus member, effective welding can be achieved.

[0265] In the embodiments of the present application, when the accommodating part 121 has the second accommodating groove 12120, depending on the configuration of the battery core assembly 2, the fitting between the battery core assembly 2 and the second accommodating groove 12120 is not limited. For example, it includes, but is not limited to, two embodiments of the following third embodiment and fourth embodiment.

[0266] When combined with Figure 32, in the third embodiment, the active material coating section 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211, and the conductive section 22 is electrically connected to the current collector 211 and includes a tab section 221 which includes a plurality of tab sheets 2211, the plurality of tab sheets 2211 which gather at a position close to the current collector 211 to form a first convergence section 2212, the plurality of tab sheets 2211 which gather and connect at a position away from the current collector 211 to form a second convergence section 2213, and the first convergence section 2212 connects the second convergence section 2213 and the active material coating section 21. If the housing section 121 has a second housing groove 12120, at least a portion of the second convergence section 2213 is housed in the second housing groove 12120.

[0267] As for what needs to be explained, 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 first embodiment, and the explanation of the first embodiment can be found by referring to that, so the explanation will be omitted here. In the third embodiment, the tab portion 221 includes a second convergence portion 2213 formed by bringing together and connecting a plurality of tab sheets 2211, so that at least a part of the second convergence portion 2213 can be housed in the second housing groove 12120, facilitating the assembly of the conductive portion 22 and the first pole column 12.

[0268] In some arbitrary examples, by combining Figure 32, the connection position of the first convergence section 2212 and the second convergence section 2213 can be positioned corresponding to the first through-hole 12130. In other words, in the projection plane perpendicular to the axial direction R of the first pole column 12, the orthographic projection of the connection position of the first convergence section 2212 and the second convergence section 2213 lies within the orthographic projection range of the first through-hole 12130. This allows the second convergence section 2213 to easily enter the first through-hole 12130 over a short distance and enter the second housing groove 12120, thereby reducing redundancy and costs.

[0269] As will be understood, the convergence position of the tab sheet 2211 can be related to the position of the first through hole 12130, and for example, by adopting the above-mentioned symmetrical convergence configuration or asymmetrical convergence configuration, it is possible to realize that the connection position of the first convergence part 2212 and the second convergence part 2213 is set corresponding to the first through hole 12130, but the explanation of this will be omitted here. Also, referring to the above, if the second convergence part 2213 is formed into a plate-like structure by ultrasonic tack welding, it becomes easier for the second convergence part 2213 to penetrate the first through hole 12130.

[0270] When combined with Figure 32, in this third embodiment, the housing portion 121 may have a second housing groove 12120, as well as a third housing groove 12140 located on the side of the second housing groove 12120 that is close to the active material coated portion 21. The surface of the first pole column 12 facing the active material coated portion 21 is the inner end face 122 of the pole column, and the groove opening of the third housing groove 12140 is formed on the inner end face 122 of the pole column. The third housing groove 12140 and the second housing groove 12120 communicate through the first through hole 12130, and in this case, at least a part of the first converging portion 2212 can be housed in the third housing groove 12140.

[0271] In the above proposed technology, at least a portion of the first convergence portion 2212 of the tab portion 221 is housed in the third housing groove 12140, and at least a portion of the second convergence portion 2213 is housed in the second housing groove 12120. This allows for more efficient use of the space within the first pole column 12 to accommodate a larger active material coated portion 21, further reducing the space occupied by the tab portion 221 within the casing 11, thereby improving the energy density of the battery cell 10. Furthermore, it is possible to better reduce the redundancy of the tab portion 221 within the casing 11, further reduce the probability of a short circuit between the tab portion 221 and the active material coated portion 21, and further reduce the risk of the tab portion 221 being reverse-inserted toward the active material coated portion 21.

[0272] It should be noted that the specific shape of the third accommodating groove 12140 is not limited and may be regular or irregular in shape. For example, it may be a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a semi-elliptical groove with an elliptical cross-section and gradually changing cross-sectional dimensions. In some embodiments of the present application, the third accommodating groove 12140 can be configured to have a shape in which the length of the cross-section is greater than the width, such as a rectangle, ellipse, or oblong, which is advantageous for accommodating the first converging portion 2212.

[0273] In the third embodiment, the second convergence portion 2213 is electrically connected to the first pole column 12 directly or indirectly. For example, if the second convergence portion 2213 is directly electrically connected to the first pole column 12, for example, if the second convergence portion 2213 is welded to the first pole column 12, the configuration 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. The method and location of the direct electrical connection between the second convergence portion 2213 and the first pole column 12 are not limited. For example, the electrical connection point between the second convergence portion 2213 and the first pole column 12 may be located on the second end wall 12121 and / or the second side wall 12123. Furthermore, the electrical connection point between the second convergence portion 2213 and the second end wall 12121 may extend along the length or width of the second end wall 12121. Moreover, the second end wall 12121 may have a second recessed groove 12122, and the electrical connection point between the second convergence portion 2213 and the second end wall 12121 may be located within the second recessed groove 12122. For corresponding technical effects, please refer to the description of the above embodiment, which will be omitted here.

[0274] In an optional technical configuration, the conductive portion 22 may be further fitted with an adapter sheet 222 as needed, in which case the second convergence portion 2213 is indirectly electrically connected to the first pole 12. Specifically, combining Figure 33, when the conductive portion 22 includes an adapter sheet 222, the adapter sheet 222 is connected to the second convergence portion 2213, and the conductive portion 22 is electrically connected to the first pole 12 via the adapter sheet 222. In this case, at least a portion of the adapter sheet 222 is housed in the second housing groove 12120, and in this example, at least a portion of the second convergence portion 2213 is also housed in the second housing groove 12120.

[0275] In the above proposed technology, the active material coated portion 21 can achieve electrical connection with the first pole column 12 via the first convergence portion 2212, the second convergence portion 2213, and the adapter sheet 222, respectively. The electrical connection position between the conductive portion 22 and the first pole column 12 is located on the adapter sheet 222, and the electrical connection can be achieved, for example, by welding (e.g., laser welding) between the adapter sheet 222 and the first pole column 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).

[0276] In the above proposed technology, by housing at least a portion of the second convergence portion 2213 and at least a portion of the adapter sheet 222 within the second housing groove 12120, the space within the first pole column 12 can be utilized more effectively, the space occupied by the conductive portion 22 within the casing 11 can be further reduced, and the volumetric energy density of the battery cell 10 can be further improved. In addition, by installing the sheet-structured adapter sheet 222, it becomes easier for the adapter sheet 222 to penetrate the first through-hole 12130 and extend into the second housing groove 12120.

[0277] Furthermore, by using the adapter sheet 222 to achieve an indirect electrical connection between the second convergence section 2213 and the first pole column 12, the adapter sheet 222 can be welded to the first pole column 12 using the portion of the adapter sheet 222 that avoids the second convergence section 2213. This ensures a secure weld between the adapter sheet 222 and the first pole column 12, reducing the risk of welding cracks and further improving the reliability and stability of the battery cell 10. At the same time, electrically connecting the first pole column 12 and the tab sheet 2211 via the adapter sheet 222 simplifies the structure of the tab sheet 2211.

[0278] Here, the method and location of direct electrical connection between the adapter sheet 222 and the first pole column 12 are not limited. For example, the adapter sheet 222 and the first pole column 12 are electrically connected by welding. For example, the electrical connection location between the adapter sheet 222 and the first pole column 12 may be located on the second end wall 12121 and / or the second side wall 12123, and furthermore, the electrical connection location between the adapter sheet 222 and the second end wall 12121 may extend along the length or width of the second end wall 12121, and furthermore, the second end wall 12121 may have a second recessed groove 12122, and the electrical connection location between the adapter sheet 222 and the second end wall 12121 may be located within the second recessed groove 12122, and so on. For corresponding technical effects, please refer to the description of the above embodiment, which will be omitted here. If the electrical connection point between the adapter sheet 222 and the first pole column 12 is located at the second end wall 12121 and / or the second side wall 12123, at least a portion of the adapter sheet 222 is housed in the second housing groove 12120, thereby simplifying the structure of the adapter sheet 222, reducing redundancy, and lowering costs.

[0279] When combined with Figure 33, in the fourth embodiment, the active material coated section 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211, and the conductive section 22 includes a tab section 221 containing a plurality of tab sheets 2211 electrically connected to the current collector 211 and an adapter sheet 222, wherein the plurality of tab sheets 2211 gather at a position close to the current collector 211 to form a first convergence section 2212, and the plurality of tab sheets 2211 gather and connect at a position away from the current collector 211 to form a second convergence section 2213, and the adapter sheet 222 is electrically connected to the second convergence section 2213. If the housing section 121 has a second housing groove 12120, at least a portion of the adapter sheet 222 can be housed in the second housing groove 12120 and electrically connected to the first pole column 12.

[0280] In the above-described technical proposal, the fourth embodiment, compared to the technical proposal of the third embodiment which includes the adapter sheet 222, has at least a portion of the adapter sheet 222 housed in the second housing groove 12120. However, the relative position of the tab portion 221 and the second housing groove 12120 is not restricted. That is, at least a portion of the tab portion 221 can be housed in the second housing groove 12120, or the tab portion 221 can be located completely outside the second housing groove 12120. This allows for the fulfillment of different structural design requirements.

[0281] In the above proposed technology, by housing at least a portion of the adapter sheet 222 in the second housing groove 12120, the adapter sheet 222 can occupy space within the first pole column 12. This reduces the space occupied by the adapter sheet 222 within the casing 11, thereby accommodating a larger active material coating portion 21 and improving the energy density of the battery cell 10. Furthermore, it reduces the probability of a short circuit between the adapter sheet 222 and the active material coating portion 21, thereby reducing the risk of a short circuit in the battery core assembly 2, and improving the stability and reliability of the battery cell 10.

[0282] Furthermore, by using the adapter sheet 222 to achieve an indirect electrical connection between the second convergence section 2213 and the first pole column 12, the adapter sheet 222 can be welded to the first pole column 12 using the portion of the adapter sheet 222 that avoids the second convergence section 2213. This ensures a secure weld between the adapter sheet 222 and the first pole column 12, reducing the risk of welding cracks and further improving the reliability and stability of the battery cell 10. At the same time, electrically connecting the first pole column 12 and the tab sheet 2211 via the adapter sheet 222 simplifies the structure of the tab sheet 2211.

[0283] Combining with Figure 34, in some other embodiments of the present application, the housing portion 121 has a fourth housing groove 12150, the surface of the first pole post 12 away from the active material coated portion 21 is the outer end face 123 of the pole post, the groove opening of the fourth housing groove 12150 is formed on the outer end face 123 of the pole post, the fourth housing groove 12150 communicates with the inside of the casing 11 via a second through hole 12160, and the conductive portion 22 does not have to be housed in the fourth housing groove 12150; for example, the conductive portion 22 may be drilled in the second through hole 12160, and the position where the conductive portion 22 is electrically connected to the first pole post 12 may be located on the hole wall of the second through hole 12160 in which the first pole post 12 is formed.

[0284] In the above embodiment, by installing the fourth housing groove 12150, electrical connection between the conductive part 22 and the hole wall of the second through hole 12160 can be easily achieved. Furthermore, depending on the case, sealing of the second through hole 12160 can be achieved by utilizing the electrical connection between the conductive part 22 and the first pole column 12. For example, by welding the conductive part 22 and the hole wall of the second through hole 12160 at the position where the second through hole 12160 and the fourth housing groove 12150 are connected, the operation can be made easier, and by controlling the weld marks, sealing of the second through hole 12160 can be achieved using the weld marks and the conductive part 22, thereby improving the problem of electrolyte leakage from the casing 11 through the second through hole 12160.

[0285] It should be noted that the specific shape of the fourth receiving groove 12150 is not limited and may be regular or irregular in shape. For example, it may be a cylindrical groove with a rectangular, elliptical, or oblong cross-section, a trapezoidal groove with a rectangular cross-section and gradually changing cross-sectional dimensions, a hemispherical groove with a circular cross-section and gradually changing cross-sectional dimensions, or a semi-elliptical groove with an elliptical cross-section and gradually changing cross-sectional dimensions.

[0286] In the embodiment of the present application, the shape of the second through-hole 12160 may be elongated to conform to 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, if the second through-hole 12160 is elongated, the fourth accommodating groove 12150 may be constructed with a cross-sectional length greater than its width, for example, a rectangle, ellipse, or oblong shape. 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 allowing for full use of the space.

[0287] It should be noted that the housing portion 121 in the embodiments of the present application is not necessarily limited to having at least one housing groove as described above. For example, in some other embodiments of the present application, when combined with Figure 35, the housing portion 121 may have only a third through hole 12170, the surface of the first pole column 12 facing the active material coated portion 21 is the inner end face 122 of the pole column, the surface of the first pole column 12 away from the active material coated portion 21 is the outer end face 123 of the pole column, the third through hole 12170 is in the form of a through hole and penetrates the inner end face 122 and the outer end face 123 of the pole column, 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 first pole column 12 is not limited. For example, the electrical connection position may be located at the hole wall where the third through-hole 12170 of the first pole column 12 is formed, or the conductive portion 22 may penetrate the third through-hole 12170 such that the electrical connection position is located on the outer end face 123 of the pole column outside the third through-hole 12170. Furthermore, the shape of the third through-hole 12170 is not limited. It may be a regularly shaped hole with equal cross-sections, or a hole with an irregular cross-sectional shape with unequal cross-sections. Moreover, the cross-sectional shape of the third through-hole 12170 is not limited. It may be elongated, such as rectangular, elliptical, or oblong, to match the sheet-like local shape 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 further explanation is omitted here.

[0288] Combining Figures 36 to 38, in some embodiments of the present invention, the battery cell 10 further includes a support 3 located within the casing 11 and adjacent to the first pole column 12 of the active material coated portion 21, the support 3 having a relief hole 31 to avoid the conductive portion 22, the conductive portion 22 can extend through the relief hole 31 and away from the active material coated portion 21 of the support 3 so as to be welded to the first pole column 12, thereby ensuring that the battery cell 10 can be charged and discharged normally.

[0289] In the above proposed technology, by installing the support 3 on the side of the active material coated section 21 that is close to the first pole column 12, the support 3 can be used to separate the active material coated section 21 from the casing 11, thereby improving the reliability of the battery cell 10. Furthermore, by providing a relief hole 31 in the support 3, the conductive section 22 can be guided and restrained to penetrate the relief hole 31 and engage with the first pole column 12. This eliminates the need to route the conductive section 22 away from the edge of the support 3 to approach the first pole column 12, further simplifying the arrangement of the conductive section 22, saving material for the conductive section 22, and reducing costs. In addition, the support 3 can support and guide the engagement between the conductive section 22 and the first pole column 12, reducing the risk of short-circuit connection between the conductive section 22 and the active material coated section 21, and further improving the reliability of the battery cell 10.

[0290] By combining Figures 36 to 38, selectively, the support 3 is 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 which extends to the housing portion 121.

[0291] To explain, the guide portion 32 protrudes from the support 3 and extends into the housing portion 121, and at least a portion of the relief hole 31 is formed within the guide portion 32, so that at least a portion of the conductive portion 22 can be easily housed in the housing portion 121 when the conductive portion 22 is drilled into the relief 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 fitting between the support 3 and the first pole column 12, and between the support 3 and the conductive portion 22, more tight and secure, making the structure of the battery cell 10 more compact and further advantageous for improving the energy density of the battery cell 10.

[0292] By combining Figures 36 to 38, a third groove 38 is selectively provided in the support 3, and at least a portion of the first pole column 12 located inside the casing 11 is accommodated within the third groove 38.

[0293] In the above proposed technology, a third groove 38 is provided in the support 3, and at least a portion of the first pole column 12 located inside the casing 11 is housed in the third groove 38. This improves the compactness of the structure, is advantageous in reducing the space occupied by the support 3 inside the casing 11, and is advantageous in improving the volumetric energy density of the battery cell 10.

[0294] Furthermore, in some embodiments, the guide portion 32 can be involved in defining the third groove 38, thereby simplifying the structure of the support 3, reducing the difficulty of designing and manufacturing the support 3, and is advantageous for increasing the wall thickness of the guide portion 32 and improving the guiding reliability of the guide portion 32.

[0295] Combining Figures 36 to 38, selectively, the escape hole 31 includes a first hole step 311 and a second hole step 312, the second hole step 312 is located on the side of the first hole step 311 that is close to the active material coated portion 21, and the cross-sectional area of ​​the second hole step 312 gradually increases along the direction away from the first hole step 311. The active material coated section 21 includes a current collector 211 and an active material layer 212 provided on the current collector 211. The conductive section 22 is electrically connected to the current collector 211 and includes a tab section 221 containing a plurality of tab sheets 2211. The plurality of tab sheets 2211 gather at a position close to the current collector 211 to form a first convergence section 2212, and the plurality of tab sheets 2211 gather and connect at a position away from the current collector 211 to form a second convergence section 2213. When the first convergence section 2212 connects to the second convergence section 2213 and the active material coated section 21, at least a portion of the first convergence section 2212 can be housed in a second hole step 312, and the second convergence section 2213 can be drilled in the first hole step 311.

[0296] In the above-described technical proposal, by arranging the relief hole 31 to include a second hole step 312 that gradually widens toward the active material coated portion 21, it is possible to accommodate more first convergence portions 2212 in the second hole step 312, improving the compactness of the fitting between the support 3 and the battery core assembly 2, reducing the overall volume of the battery cell 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-described technical proposal, a detailed explanation of the first convergence portion 2212 and the second convergence portion 2213 has already been described in the above-described embodiment, and will be omitted here.

[0297] In some embodiments of the present invention, the support 3 may be an integral structure or a separate structure. Combining Figure 39, when the support 3 is an integral structure, the relief hole 31 is formed as a through-hole that penetrates the support 3. Therefore, an integral support 3 is easy to process, relatively reliable, and easy to assemble with the casing assembly 1, improving assembly efficiency and fitting stability. As can be seen, how the support 3 is processed can be specifically selected depending on the material of the support 3. For example, if the support 3 is an insulating plastic member, an integral support 3 can be obtained by injection molding.

[0298] When Figure 40 is combined, if support 3 is a separate structure, support 3 includes a removable first support 33 and a second support 34, both of which are elongated plate-like structures and can be detachably connected. For example, they can be fitted together by insertion or engagement, making assembly easy. Furthermore, the first support 33 has a semi-perforated structure on the side adjacent to the second support 34, and the second support 34 also has another semi-perforated structure of a suitable shape 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, a relief hole 31 is defined between the first support 33 and the second support 34.

[0299] In the above proposed technology, the relief hole 31 is defined by the fitting of the first support 33 and the second support 34. When assembling the support 3 and the battery core assembly 2, it is not necessary to pass the conductive part 22 from one end of the relief hole 31 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 relief hole 31 surrounds the conductive part 22. This makes the assembly of the support 3 and the battery core assembly 2 easier and improves assembly efficiency.

[0300] As an alternative technical option, if the cross-section of the relief hole 31 is elongated, the first support 33 and the second support 34 are positioned on both sides of the relief hole 31 in the width direction. For example, if the width direction of the relief hole 31 is left-right, the first support 33 and the second support 34 are located on the left and right sides of the relief hole 31, thereby facilitating the fitting of the first support 33 and the second support 34 with the conductive part 22.

[0301] By combining Figures 36, 41, and 42, it can be seen that in the embodiment of the present application, the configuration of the support 3 is not limited thereto, and the edge of the support 3 opposite the casing cover 112 can further have a casing-in guide surface 35 installed, the casing-in guide surface 35 including an inclined or curved surface and performing an orthographic projection along the axial radius R of the first pole column 12, the orthographic projection of the active material coated portion 21 is entirely located within the orthographic projection range of the support 3, and the orthographic projection range of the support 3 exceeds the orthographic projection range of the active material coated portion 21. The casing-in guide surface 35 can act as a guide, allowing the support 3 to be smoothly assembled into the casing body 111, and the active material coated portion 21 enters the casing body 111 after the support 3 has entered the casing body 111, reducing the problem of the casing body 111 damaging the active material coated portion 21. During assembly, the support 3 and battery core assembly 2 can be pre-assembled. This pre-assembled assembly is then attached to the casing 11. During attachment, the support 3 is positioned at the front end of the active material coating section 21, meaning the support 3 enters the casing 11 before the active material coating section 21. This reduces the difficulty of the support 3 entering 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 coating section 21, reducing the probability of scratches between the active material coating section 21 and the casing 11, thereby improving assembly efficiency and success rate. Additionally, the contact area between the support 3 and the active material coating section 21 can be increased, mitigating stress concentration problems and allowing for the omission of other structural components.

[0302] When combined with Figure 41, in some embodiments of the present invention, the battery cell 10 further includes an inner insulating member 4, the inner insulating member 4 is located inside the casing 11 and includes the outside of the active material coated portion 21, and the inner insulating member 4 is connected to a support 3. In the above embodiments, by enclosing the outside of the active material coated portion 21 with the inner insulating member 4, the insulation reliability between the active material coated portion 21 and the casing 11 is improved, corrosion of the casing 11 due to contact between the active material coated portion 21 and the casing 11 is reduced or prevented, the problem of electrolyte leakage due to corrosion of the casing 11 is reduced, and the reliability of the battery cell 10 is improved. On the other hand, by connecting the inner insulating member 4 to the support 3, the difficulty of fixing the inner insulating member 4 is reduced and the reliability of the inner insulating member 4 enclosing the outside of the active material coated portion 21 is improved.

[0303] When combined with Figure 41, in the embodiment of the present invention, the support 3 includes a main body portion 36 located on the side of the active material coating portion 21 adjacent to the first pole column 12, and an extended portion 37 connected to the main body portion 36 and located in the outer peripheral region of the active material coating portion 21. The extended portion 37 is used to fit positionally to the active material coating portion 21, improving the problem of corrosion caused by overlapping toner that has fallen off the edge of the active material coating portion 21 with the casing 11. The extended portion 37 is also used to fix the inner insulating member 4, improving the reliability of the connection between the inner insulating member 4 and the support 3, and providing a relatively good insulating effect.

[0304] For example, when Figure 41 is combined, the main body 36 and the extension 37 can define a positioning groove 39 located on the side of the extension 37 away from the active material coated portion 21. 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 36. This protects the inner insulating member 4 with the main body 36 when it is attached to the casing, reducing the probability of scratches between the inner insulating member 4 and the casing 11.

[0305] Specifically, when Figure 42 is combined, the inner insulating member 4 may be an integral film having main body portions 41 located on both sides in the thickness direction of the active material coated portion 21 and connecting portions 42 connecting the two main body portions 41. The connecting portions 42 are located on the side of the active material coated portion 21 away from the first pole column 12, and the edge of the main body portion 41 away from the connecting portions 42 extends to the extended portion 37 and is connected to the extended portion 37. This provides relatively good insulating performance and facilitates connection.

[0306] In some embodiments, the casing assembly 1 includes at least one first pole post 12 which is riveted to the casing body 111.

[0307] In the above proposed technology, since the first pole column 12 is connected to the casing body 111 by riveting, it is difficult to weld if the casing body 111 is made thin, but it is relatively easy to rive the first pole column 12 to the casing body 111. In other words, connecting the first pole column 12 and the casing body 111 by riveting is easy to install and operate, and riveting the first pole column 12 to the casing body 111 is advantageous for thinning and lightening the casing body 111, thereby reducing the weight of the battery cell 10. If the dimensions of the battery cell 10 are fixed, riveting the first pole column 12 makes it easy to thin the casing body 111, which is also advantageous for increasing the internal space of the casing body 111, thereby improving the energy density of the battery cell 10.

[0308] For example, in some embodiments, by combining Figures 43 to 45, the first pole column 12 may be an integral structure and riveted to the casing 11. This improves the assembly efficiency of the first pole column 12, reduces the height to which the first pole column 12 protrudes from the surface of the casing 11, which is advantageous for improving energy density and also for improving compactness.

[0309] Specifically, by combining Figures 43 to 45, the first pole column 12 can include a stopper portion 1281 and a drilled portion 1282 before riveting. During assembly, the stopper portion 1281 is secured inside the casing 11, and after drilling the drilled portion 1282 into the mounting hole 113, the portion of the drilled portion 1282 located outside the casing 11 is riveted to form a flange portion 1283. The flange portion 1283 is secured outside the casing 11, thereby achieving the installation of the first pole column 12. To explain further, in this case, the drilled portion 1282 is the pole column body of the first pole column 12, the flange portion 1283 is the first position limiting base of the first pole column 12, and the stopper portion 1281 is the second position limiting base of the first pole column 12.

[0310] By selectively combining Figures 43 and 44, the casing assembly 1 may include several seal pads fitted between the casing 11 and the first pole post 12, such as the first seal pad 191 and the second seal pad 192 shown in Figure 43. The seal pads are assembled in place before riveting, and after riveting the first pole post 12, the first pole post 12 presses against the seal pads to form a seal, thereby improving the sealing performance of the mating area between the first pole post 12 and the casing 11 by utilizing the seal pads. The number, position, and material of the seal pads are not limited; for example, the material may be silicone, plastic, etc.

[0311] Selectively, combining Figure 44, the flange portion 1283 may have a length c of 1 mm or more and a thickness d of 2 mm or more in order to improve the riveted joint strength of the first pole column 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 first pole column 12 and the casing 11 decreases under relatively strong vibrations.

[0312] Furthermore, in other embodiments of the present invention, by combining Figures 9 and 10, the first pole column 12 can be attached to the casing 11 as a separate structure by welding. For example, the first pole column 12 includes a first portion 1291 and a second portion 1292, where at least a part of the first portion 1291 is located outside the casing 11 and at least a part of the second portion 1292 is located inside the casing 11. The first pole column 12 can be attached by drilling a mounting hole 113 in at least one of the first portion 1291 and the second portion 1292 and welding (for example, laser welding) the other portion.

[0313] In some selective embodiments, combining Figures 48 and 49 results in multiple first pole columns 12, all located on the same side surface of the casing 11, thus facilitating installation and improving assembly efficiency.

[0314] It should be noted that the arrangement of the multiple first pole columns 12 on the same side surface is not limited, and for example, when the cross-section of the first pole column 12 is an elongated shape, for example, when the length of the cross-section is three times or more the width of the cross-section, for example, when it is elliptical, oblong, or rectangular, it has relatively good adaptability to a thin, flat casing 11. For example, the multiple first pole columns 12 are all provided on one side surface (denoted as the first wall surface 110) in the height direction of the casing 11, the length direction of each first pole column 12 all coincides with the length direction of the first wall surface 110 of the casing 11, and the multiple first pole columns 12 are separated along the length direction and / or width direction of the first wall surface 110.

[0315] For example, in the example shown in Figure 48, if the first wall surface 110 has two first pole columns 12, the two first pole columns 12 are separated along the longitudinal direction of the first wall surface 110. Selectively combining Figure 48, the portion of the first pole column 12 located outside the casing 11 (referred to as the pole column exterior) is annular, and in the longitudinal direction of the first wall surface 110, the length a1 of the inner ring of the pole column exterior is at least 1 / 3 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 column exterior is at least 3 / 4 of the width b0 of the first wall surface 110. This is advantageous in providing a relatively large area for the first pole column 12 to electrically connect with the bus member, thereby facilitating further improvement of the current passing capability of the first pole column 12. For example, the length a1 of the inner ring outside the pole column is 50 mm or more, and the width b1 of the inner ring outside the pole column is 30 mm or more.

[0316] Furthermore, combining with Figure 48, when the first wall surface 110 has two first pole columns 12 and the two first pole columns 12 are separated along the longitudinal direction of the first wall surface 110, in some selective embodiments, the first pole column 12 includes a portion located inside the casing 11 (referred to as the pole column interior), and in the longitudinal direction of the first wall surface 110, the length of the pole column interior is 1 / 3 or more of the length of the first wall surface 110, and in the width direction of the first wall surface 110, the width of the pole column interior is 3 / 4 or more of the width of the first wall surface 110. This is advantageous in providing the first pole column 12 with a relatively large area for electrical connection with the conductive part 22, and facilitates further improvement of the current passing capability of the first pole column 12. Exemplarily, the length of the pole column interior is 50 mm or more, and the width of the pole column interior is 30 mm or more.

[0317] Furthermore, for example, in the example shown in Figure 49, if the first wall surface 110 has four first pole columns 12, two of the first pole columns 12 are spaced apart along the width direction of the first wall surface 110 to form one pair, and a total of two pairs are spaced apart along the length direction of the first wall surface 110. Selectively combining Figure 49, the portion of the first pole column 12 located outside the casing 11 (referred to as the pole column exterior) is ring-shaped, and in the length direction of the first wall surface 110, the length a2 of the inner ring of the pole column exterior is 1 / 3 or more 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 pole column exterior is 1 / 5 or more of the width b0 of the first wall surface 110. This is advantageous in providing a relatively large area for the first pole column 12 to electrically connect with the bus member, thereby facilitating further improvement of the current passing capability of the first pole column 12. For example, the length a2 of the inner ring outside the pole column is 50 mm or more, and the width b2 of the inner ring outside the pole column is 8 mm or more.

[0318] Furthermore, combining with Figure 49, if the first wall surface 110 has four first pole columns 12, two of these first pole columns 12 form a pair separated along the width direction of the first wall surface 110, and a total of two pairs separate along the length direction of the first wall surface 110, then in some selective embodiments, the first pole columns 12 include a portion located inside the casing 11 (referred to as the pole column interior), and in the length direction of the first wall surface 110, the length of the pole column interior is 1 / 3 or more of the length of the first wall surface 110, and in the width direction of the first wall surface 110, the width of the pole column interior is 1 / 5 or more of the width of the first wall surface 110. This is advantageous in providing the first pole columns 12 with a relatively large area for electrical connection with the conductive part 22, and facilitates further improvement of the current passing capability of the first pole columns 12. Exemplarily, the length of the pole column interior is 50 mm or more, and the width of the pole column interior is 8 mm or more.

[0319] In some embodiments, when Figures 48 and 49 are combined, the portion of the first pole column 12 is located inside the casing 11, the portion of the first pole column 12 is located outside the casing 11, and the orthographic area of ​​the portion of the first pole column 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, the orthographic area of ​​the portion of the first pole column 12 located outside the casing 11 on the first wall surface 110 is 5%, 6%, 7%, 8%, 9%, 10%, or more of the area of ​​the first wall surface 110. This is advantageous in increasing the connection area between the first pole column 12 and the bus member, improving the effective current passage area between the first pole column 12 and the bus member, and improving the charging speed of the battery cell 10.

[0320] Furthermore, in some embodiments, when Figure 50 is combined, the vertical height t1 from the portion of the first pole column 12 that protrudes from the outer surface of the first wall surface 110 (referred to as the outer pole column) to the first wall surface 110 may be 3.2 mm or less, and the vertical height t2 from the portion of the first pole column 12 that protrudes from the inner surface of the first wall surface 110 (referred to as the inner pole column) to the first wall surface 110 may be 2 mm or less, thereby improving the volumetric energy density of the battery cell 10.

[0321] Referring again to Figures 50 to 56, the casing 11 specifically includes a casing body 111 and a casing cover 112. The casing body 111 is a rectangular annular structure with one or both ends open. When one end is open, there is one casing cover 112 which covers the open position. When both ends are open, there are two casing covers 112 which cover the open ends of the casing body 111.

[0322] In detail, if 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 is a single molded product, and may specifically be a rectangular structure formed by stretching. In this case, the first pole column 12 can be provided on at least one of either the casing body 111 or the casing cover 112. Exemplarily, combining Figure 51, the first pole column 12 may specifically be installed on the end of the casing body 111 that is away from the casing cover 112. When the battery cell 10 is used in a vibrating environment, the amplitude of the connection between the casing body 111 and the casing cover 112 is relatively small, and the connection point between the casing body 111 and the casing cover 112 is less prone to cracking, thus improving the reliability of the battery cell 10. Furthermore, the wall thickness of the casing body 111 can be reduced, thereby reducing costs, weight, and enabling miniaturization of the battery cell 10.

[0323] As a selective solution, if we recombine Figure 51, when there are multiple first pole columns 12, all first pole columns 12 are provided at one end of the casing body 111 that is away from the casing cover 112. This allows the amplitude of the connection between the casing body 111 and the casing cover 112 to be relatively small when the battery cell 10 is used in a vibrating environment, and the connection point 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 wall thickness e1 of the end wall of the casing body 111 that is away from the casing cover 112 can be reduced to 2 mm or less, and the wall thickness e2 of the side wall connecting the end wall of the casing body 111 and the casing cover 112 can be reduced to 0.8 mm or less, thereby reducing costs, weight, and enabling miniaturization of the battery cell 10.

[0324] When the first housing groove 12110 is provided on the first pole post 12 corresponding to the mounting hole 113, the thickness of the portion of the first housing groove 12110 on the side away from the active material coated portion 21 of the first pole post 12 is thin, so welding of the conductive portion 22 and the first pole post 12 can be achieved from the outside of the casing 11, and as shown in Figure 51, the casing 11 includes the casing body 111 and the casing cover 112, and the casing cover 112 is the casing body 11 When provided at the open end of 1, even if the first pole post 12 is provided at the sealed end of the casing body 111, there is no need to worry that it will be difficult to weld the conductive part 22 and the first pole post 12 from inside the casing 11. The conductive part 22 and the first pole post 12 can be welded from outside the casing 11. As a result, by providing the first pole post 12 at the sealed end of the casing body 111, the connection stability and reliability between the casing body 111 and the casing cover 112 can be improved.

[0325] When the second housing groove 12120 is provided on the first pole column 12, welding of the conductive part 22 and the first pole column 12 can be achieved from outside the casing 11 through the groove opening of the second housing groove 12120. Combining this with the arrangement shown in Figure 51, 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 first pole column 12 is provided at the sealed end of the casing body 111, there is no need to worry that welding of the conductive part 22 and the first pole column 12 from inside the casing 11 will be difficult. The conductive part 22 and the first pole column 12 can be welded from outside the casing 11, thereby improving the connection stability and reliability between the casing body 111 and the casing cover 112.

[0326] Of course, by combining Figure 52, in other embodiments of the present invention, all first pole posts 12 can be provided on the casing cover 112 as needed. This facilitates the assembly of the first pole posts 12 and the casing cover 112, and is not limited to this embodiment.

[0327] Referring again to Figures 6-8, 21, and 26-27, a specific embodiment of the battery cell 10 of the present application will be described.

[0328] Referring to Figures 6 to 8, the battery cell 10 is a rectangular parallelepiped, and the height direction of the battery cell 10 is the first direction Z, the length direction of the battery cell 10 is the second direction X, and the thickness direction of the battery cell 10 is the third direction Y. The battery cell 10 includes a casing 11 which includes a casing body 111 that is a rectangular annular structure and a casing cover 112 that is installed in the open position of the casing body 111. The casing body 111 is open at one end along the first direction Z and sealed at the other end along the first direction Z.

[0329] Referring to Figures 6 to 8, the sealing end of the casing body 111 along the first direction Z is provided with two poles, a positive pole and a negative pole, separated along the second direction X. Both pole columns are first pole columns 12 on which a housing section 121 including a second housing groove 12120 is installed. Specifically, the first pole column 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, the second end wall 12121 and the second side wall 12123 surround each other to form the second housing groove 12120, the surface of the first pole column 12 that is away from the casing cover 112 is the pole column outer end face 123, the groove opening of the second housing groove 12120 is formed on the pole column outer end face 123, and a first through hole 12130 is provided in the second end wall 12121.

[0330] Referring to Figures 8 and 21, the battery cell 10 further includes a battery core assembly 2 including an active material coated portion 21 and a tab portion 221, the active material coated portion 21 being housed within the casing 11, the tab portion 221 extending through a first through hole 12130 into a second housing groove 12120 and welded to a second end wall 12121, electrically connecting the active material coated portion 21 and the first pole column 12 via the tab portion 221.

[0331] By combining Figures 21, 26, and 27, the first cover plate 13 is fitted into the groove opening of the second housing groove 12120. After welding of the tab portion 221 to the second end wall 12121 is completed, the groove opening of the second housing groove 12120 is sealed by utilizing the fitting between the first cover plate 13 and the first pole post 12. The first cover plate 13 is welded to the first pole post 12 to form an electrical connection. Subsequently, if a bus member is used to make an electrical connection between the battery cells 10, the bus member may be welded to the first cover plate 13 to achieve an electrical connection with the first pole post 12.

[0332] In the above proposed technology, on the one hand, by installing the second housing groove 12120 on the first pole column 12, the weight of the first pole column 12 can be reduced to some extent, thereby improving the gravimetric energy density of the battery cell 10 and the battery 100. On the other hand, the groove opening of the second housing groove 12120 is formed on the outer end surface 123 of the pole column, and the outer end surface 123 of the pole column is the surface away from the active material coated portion 21 of the first pole column 12, so the second housing groove 12120 is the active material coated portion The tab portion 221 can be opened in a direction away from the fabric portion 21, thereby accommodating at least a part of the tab portion 221 in the second housing groove 12120. This allows for easy accommodation and organization of the tab portion 221 through the groove of the second housing groove 12120, and facilitates welding operations between the tab portion 221 and the first pole column 12 through the groove of the second housing groove 12120. This reduces the difficulty of producing the battery cell 10 and improves the production efficiency of the battery cell 10.

[0333] Furthermore, since welding of the tab portion 221 and the first pole column 12 can be achieved from outside the casing 11, the first pole column 12 may be provided at the sealing end of the casing 111. In this way, when the battery cell 10 is used in a vibrating environment, the amplitude of the connection between the casing body 111 and the casing cover 112 is relatively small, cracking is less likely to occur at the connection point between the casing body 111 and the casing cover 112, the reliability of the battery cell 10 can be improved, the wall thickness of the casing body 111 can be reduced, which is advantageous for reducing costs, reducing weight, and miniaturizing the battery cell 10.

[0334] At the same time, since the second housing groove 12120 can pass through the first through hole 12130 and communicate with the inside of the casing 11, the second housing groove 12120 may also be used as a buffer and temporary storage structure for the electrolyte, allowing the casing 11 to accommodate more electrolyte. As electrolyte is consumed during the charging and discharging process of the battery cell 10, having more electrolyte can extend the service life of the battery cell 10. Furthermore, since the second housing groove 12120 passes through the first through hole 12130 and communicates with the inside of the casing 11, the second housing groove 12120 can also be used as a gas containment and buffer structure for gases generated inside the battery core assembly 2, reducing the expansion of the battery cell 10 and improving the reliability and stability of the battery cell 10.

[0335] Combining Figures 45 and 59, in some embodiments, the first pole column 12 includes an integrally molded pole column body, a first position limiting base and a second position limiting base, the pole column body is drilled in a mounting hole 113, and the first and second position limiting bases are installed at both ends of the pole column body along the axial direction of the mounting hole 113 so as to rive the first pole column 12 to the casing body 111, the first position limiting base is fitted to the outside of the casing body 111 in a position-limiting manner, and the second position limiting base is fitted to the inside of the casing body 111 in a position-limiting manner.

[0336] The first and second position limiting bases extend radially outward from the peripheral wall of the mounting hole 113 along the radial direction of the mounting hole 113, the first position limiting base can restrict the movement of the first pole column 12 relative to the casing body 111 in the direction toward the inside of the casing body 111, and the second position limiting base can restrict the movement of the first pole column 12 relative to the casing body 111 in the direction toward the outside of the casing body 111, thereby facilitating secure mounting of the first pole column 12 to the mounting hole 113 via the first and second position limiting bases, which is advantageous for riveting the first pole column 12 to the casing body 111, and facilitating the assembly of the first pole column 12 to the casing body 111. There is no need to use any other connection method between them, which facilitates a secure connection between the first pole column 12 and the casing body 111, is advantageous in simplifying the structure of the casing assembly 1, simplifies the assembly process of the casing assembly 1, and at the same time, the pole column body of the first pole column 12, the first position limiting base and the second position limiting base are integrally molded, saving materials and costs, as well as guaranteeing the strength of the first pole column 12. After the first pole column 12 is fitted into the casing 11, it is less likely to separate from the casing 11 due to vibration or external pulling during the charging and discharging process of the battery cell 10, and is less likely to crack or break due to vibration or external pulling, thus improving the stability and reliability of the battery cell 10.

[0337] When Figure 60 is combined, in some embodiments, the dimension of the first pole column 12 in the first direction is larger than the dimension of the pole column 12 in the second direction, the first direction and the second direction are perpendicular, and both the first direction and the second direction are perpendicular to the axial direction of the mounting hole 113.

[0338] In the planes forming the first and second directions, the orthographic shape of the first pole column 12 may be non-circular, which is advantageous for achieving good matching between the first pole column 12 and the wall of the casing body 111 on which the first pole column 12 is installed in the first and second directions, which can improve the cross-sectional area of ​​the first pole column 12 that can be placed on the wall of the casing body 111 to some extent, which is advantageous for increasing the current-passing area of ​​the first pole column 12 within the limited placement area of ​​the wall, which is advantageous for improving the current-passing capability and heat-diffusing capability of the first pole column 12, and consequently for improving the charging speed of the battery cell 10 using the casing assembly 1.

[0339] In some embodiments, the first direction is the longitudinal direction of the cross-section of the first pole column 12, and the second direction is the width direction of the cross-section of the first pole column 12. In this case, the axial direction of the mounting hole 113 may refer to the height direction of the first pole column 12 or the axial direction of the pole column 12.

[0340] In some embodiments, in the cross-section of the first pole column 12, the dimension of the first pole column 12 in the first direction is greater than three times the dimension of the first pole column 12 in the second direction, the first direction, the second direction, and the axial direction of the mounting hole 113 are perpendicular to each other in pairs, which is advantageous for the first pole column 12 and the wall of the casing body 111 on which the first pole column 12 is located to obtain a good match in the first and second directions, the first pole column 12 makes full use of the arrangement area of ​​the wall of the casing body 111 on which the first pole column 12 is located, increasing the cross-sectional area of ​​the first pole column 12, which facilitates configuring the first pole column 12 as a "super-large pole column structure", and is advantageous for further increasing the current passage area, current passage capacity, and heat diffusion capacity of the first pole column 12.

[0341] When Figure 57 is combined, in some embodiments of the present invention, the casing body 111 has a second wall portion 1113 and a third wall portion 1114 installed opposite each other, and each of the second wall portion 1113 and the third wall portion 1114 is provided with at least one first pole column 12.

[0342] The "second wall portion 1113 and third wall portion 1114" may refer to end walls located on both sides of the casing body 111 in the third direction and extending along the first direction (see Figure 57), or they may refer to end walls located on both sides of the casing body 111 in the third direction and extending along the second direction. Next, one first pole column 12 may be installed in the second wall portion 1113 and the third wall portion 1114, or multiple first pole columns 12 may be installed.

[0343] In other words, the first pole posts 12 may be provided on two opposing sides of the casing body 111 (combining Figures 53 to 55), and when the first pole posts 12 are provided on both opposing surfaces of the casing body 111, the positions of the first pole posts 12 adjacent to each side of the active material coating section 21 can all extend from the conductive section 22, and the conductive section 22 is fitted and connected to the adjacent first pole post 12, thereby improving the problem of the tab section 221 being pulled by the first pole post 12 on the same side and causing the connection between the tab section 221 and the active material coating section 21 to break, thereby improving the reliability of the battery cell 10. It should be noted that the first pole posts 12 on both sides may be the same or different, and the method of connecting the first pole posts 12 on both sides to the conductive section 22 may be the same or different, and is not limited here.

[0344] When Figure 58 is combined, in some embodiments, the casing body 111 has a plurality of wall portions 1115, a portion of which is a first setting wall portion 1116, the area of ​​the first setting wall portion 1116 is larger than the area of ​​the other wall portions 1115, and the first pole column 12 is provided in the first setting wall portion 1116.

[0345] The "first setting wall portion 1116" may refer to the one with the largest area among the multiple wall portions 1115. In other words, the first pole column 12 is riveted to the largest wall portion of the casing body 111, and the wall portion 1115 connected to the first pole column 12 has the largest area, which makes the operation easier when riveting the first pole column 12, improves assembly efficiency, and improves the yield of the battery cells 10.

[0346] Furthermore, in some selective embodiments of the present invention, for example, the first pole column 12 may be located on the top surface of the casing body 111. When the first pole column 12 is located on the top surface of the casing body 111, the electrolyte can be contained using the housing portion 121, thereby extending the cycle life of the battery cell 10. Also, when the first pole column 12 is located on the top surface of the casing body 111 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 is increased, reducing the problem of stress concentration and allowing other support structural members to be omitted.

[0347] In some embodiments, the casing body 111 has a plurality of wall portions 1115, at least one of which is a second setting wall portion, the pressure release portion 16 is provided in the second setting wall portion, and the first pole column 12 is provided in a wall portion 1115 other than the second setting wall portion. The specific structure of the pressure release portion 16 is not limited and may be, for example, an explosion-proof valve or a weak point, and 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.

[0348] The first pole column 12 and the pressure release section 16 are located on different walls 1115. After the battery cell 10 experiences thermal runaway, the discharged high-temperature medium is released through the pressure release section 16 and cannot come into contact with the first pole column 12. In this way, the probability of a fire caused by the battery circuit coming into contact with the high-temperature medium can be reduced.

[0349] For example, the multiple wall sections 1115 may refer to the upper wall section, left wall section, right wall section, front wall section, and rear wall section of the casing body 111. Of these, the second setting wall section may refer to the upper wall section, and the first pole column 12 is installed in one or more of the left wall section, right wall section, front wall section, and rear wall section. Similarly, the second setting wall section 1117 may refer to one of the left wall section, right wall section, front wall section, and rear wall section, and the first pole column 12 is installed in the other wall section 1115. Referring to Figure 56, in some embodiments of the present application, the pressure release section 16 is provided in the casing cover 112, and the pressure release section 16 and the casing cover 112 are integrally molded.

[0350] In the above solution, by integrally molding the pressure release section 16 and the casing cover 112, the number of parts in the battery cell 10 can be reduced, thereby reducing the welding steps between the pressure release section 16 and the casing body 111. In other words, there is no step of connecting to the pressure release section 16 before or after connecting the casing cover 112 to the casing body 111. In this way, the assembly efficiency of the battery cell 10 can be improved, the cost of the welding process can be reduced, the possibility of welding position failure can be reduced, and the reliability of the battery cell 10 can be improved.

[0351] Selectively, integral molding of the pressure release section 16 and the casing cover 112 may also refer to the casing cover being molded using a notch method, i.e., the pressure release section 16 is a weaker component in the casing cover 112, and when subjected to a certain pressure, the weaker component can crack to release the pressure, and by using an integrally molded notch for the pressure release section 16 in the casing cover 112, deformation is less likely to occur during the process of the casing cover 112 being molded into the pressure release section 16, the molding process for the casing cover 112 is relatively simple, and the yield of the battery cells 10 can be improved and costs reduced.

[0352] Combining Figures 4 and 59, in some embodiments, the casing body 111 has a plurality of wall portions 1111, at least one of which is a first wall portion 1112, the first pole column 12 is riveted to the first wall portion 1112, and the thickness of the first wall portion 1112 is greater than the thickness of the other wall portions 1111.

[0353] The first wall portion 1112 serves as a casing wall connected to the first pole column 12. The thickness of the first wall portion 1112 is greater than that of the other wall portions 1111. On the one hand, the relatively large thickness of the first wall portion 1112 improves the overall strength of the casing body 111, thereby improving the reliability of the battery cell 10 during daily use. On the other hand, the relatively large thickness of the first wall portion 1112 also improves the reliability of riveting the first pole column 12, thereby improving the yield of the battery cell 10.

[0354] Assuming the reliability of the riveted joint of the first pole column 12 is met, the thickness of the first wall portion 1112 can be the normal thickness, and the thickness of the other wall portions 1111 can be reduced. In this way, if the outer contour dimensions of the casing body 111 are fixed, the internal space of the casing body 111 can be increased, and consequently, a larger active material coated portion 21 can be placed, which is advantageous in improving the energy density of the battery cell 10.

[0355] When combined with Figure 3, in some embodiments of the present application, the pressure release section 16 is provided on the first wall section 1112. That is, the pressure release section 16 and the first pole column 12 may be located on the same side surface of the casing body 111. This facilitates processing and assembly. Alternatively, the pressure release section 16 and the first pole column 12 can be further separately located on opposing sides of the casing body 111. This saves space, increases the volume of the first pole column 12, and reduces the adverse effects of the pressure release section 16 on the first pole column 12 when releasing pressure.

[0356] When Figures 51 and 56 are combined, in some embodiments of the present invention, the casing body 111 has a pressure release section 16 provided on the casing cover 112. Therefore, the pressure release section 16 is easy to manufacture and has good reliability in releasing pressure. It should be explained that in this embodiment, the first pole column 12 may be provided on the casing body 111 or the casing cover 112, and is not limited thereto. For example, the pressure release section 16 can be integrally molded with the casing cover 112, which makes manufacturing easier, simplifies assembly, improves production efficiency, and reduces costs.

[0357] In some embodiments, the ratio of the thickness of the first wall portion 1112 to the thickness of any one of the other wall portions 1111 is d1, and of these, 1 <d1≦7.5である。

[0358] The ratio d1 of the thickness of the first wall 1112 to the thickness of any one of the other wall 1111 is not appropriate if it is too small or too large. If d1 is less than 1, the thickness of the first wall 1112 cannot be greater than the thickness of the other wall 1111, and the support strength for the first pole column 12 cannot be improved. If d1 is greater than 7.5, the ratio of the thickness of the first wall 1112 to the thickness of the other wall 1111 is relatively large, the thickness of all wall 1111 is relatively large, and the thickness of the first wall 1112 is too large. Although the strength requirement can be met, this is disadvantageous in reducing the weight of the battery cell 10. Therefore, the maximum value of d1 should be 7.5. For example, d1 may be 1.2, 1.4, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, etc.

[0359] In some embodiments, 1 < d1 ≤ 2.5. As described above, considering how to improve the space inside the casing on the premise that the thickness of the casing body 111 and the outer contour dimensions of the casing body 111 are fixed, when d1 is greater than 2.5, it can ensure that the entire casing body 111 has better strength, but it sacrifices the space inside the casing and is disadvantageous for improving the energy density of the battery cell 10. Therefore, by setting d1 greater than 1 and within the range of 2.5 or less, the strength of the casing body 111 can be balanced. At the same time, on the premise that the outer contour dimensions of the casing body 111 are fixed, a relatively large space can be provided inside the casing body 111, which is advantageous for increasing the dimensions of the active material coating portion 21 and improving the energy density of the battery cell 10.

[0360] In some embodiments, as shown in FIGS. 51 and 59, the thickness of the first wall portion 1112 is e1, where 1.5 mm ≤ e1 ≤ 2.5 mm, and / or the thickness of the other wall portions 1111 other than the first wall portion 1112 is e2, where 0.3 mm ≤ e2 ≤ 0.6 mm.

[0361] When the thickness of the first wall portion 1112 is greater than the thickness of the other wall portions 1111, the thickness e1 of the first wall portion 1112 may be 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, etc. That is, when e1 is less than 1.5 mm, the thickness of the first wall portion 1112 is relatively small, the strength is insufficient, and it is disadvantageous for riveting to the first terminal post 12. When e1 is greater than 2.5 mm, the thickness of the first wall portion 1112 is too large, the casing body 111 becomes relatively thick, the cost increases, and when the outer contour dimensions of the casing body 111 are fixed, the space inside the casing body 111 decreases, and consequently, the dimensions of the active material coating portion 21 become relatively small, reducing the energy density of the battery cell 10.

[0362] Alternatively, if the thickness of the first wall portion 1112 is greater than the thickness of the other wall portions 1111, the thickness e2 of the other wall portions 1111 other than the first wall portion 1112 may be 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, etc. If e2 is less than 0.3 mm, the thickness of the other wall portions 1111 other than the first wall portion 1112 is relatively small, and even if the first wall portion 1112 has relatively good strength, if the strength of the other wall portions 1111 is insufficient, the strength of the casing body 111 will be insufficient and it will be prone to breakage. If e2 is greater than 0.6 mm, the thickness of the other wall portions 1111 other than the first wall portion 1112 is relatively large, and strength can be guaranteed, but the cost will increase, and if the outer contour dimensions of the casing body 111 are fixed, the space inside the casing body 111 will be reduced, and consequently the dimensions of the active material coated portion 21 will be reduced, which can reduce the energy density of the battery cell 10.

[0363] Of course, if the thickness of the first wall portion 1112 is greater than the thickness of the other wall portions 1111, both conditions can be satisfied simultaneously. The thickness of the first wall portion 1112 is e1, of which 1.5 mm ≤ e1 ≤ 2.5 mm, and the thickness of the other wall portions 1111 other than the first wall portion 1112 is e2, of which 0.3 mm ≤ e2 ≤ 0.6 mm.

[0364] In some embodiments, 1.8 mm ≤ e1 ≤ 2.2 mm. Specifically, e1 may be 1.8 mm, 1.85 mm, 1.9 mm, 1.95 mm, 2.0 mm, 2.1 mm, 2.2 mm, etc. The value of e1 must satisfy a certain safety margin. If e1 is less than 1.8 mm, the first wall portion 1112 can meet the strength requirements, but the relatively small thickness of the first wall portion 1112 will increase processing or manufacturing costs, and the first wall portion 1112 will be more prone to breakage under extreme working conditions. If e1 is greater than 2.2 mm, the first wall portion 1112 will meet the strength requirements, but the use of a relatively large amount of material will increase costs. If the outer contour dimensions of the casing body 111 are fixed, the internal space of the casing body 111 will be relatively small, which in turn will reduce the dimensions of the active material coated portion 21 and reduce the energy density of the battery cell 10.

[0365] In some embodiments, 0.4 mm ≤ e2 ≤ 0.55 mm. Specifically, e2 may be 0.4 mm, 0.42 mm, 0.44 mm, 0.46 mm, 0.48 mm, 0.5 mm, 0.52 mm, 0.55 mm, etc. The value of e2 must satisfy a certain safety margin. If e2 is less than 0.4 mm, the other wall portions 1111 other than the first wall portion 1112 can meet the strength requirements, but the thickness of the other wall portions 1111 is relatively small, which increases processing costs or manufacturing costs, and the other wall portions 1111 are more prone to breakage under extreme working conditions. If e2 is greater than 0.55 mm, if the other wall portions 1111 meet the strength requirements, more material will be used, increasing costs. If the outer contour dimensions of the casing body 111 are fixed, the internal space of the casing body 111 can be reduced, which in turn reduces the dimensions of the active material coated portion 21 and can reduce the energy density of the battery cell 10.

[0366] In some embodiments, the thickness of the casing cover 112 is less than the thickness of the first wall portion 1112. Since the first pole column 12 is riveted to the first wall portion 1112 and the casing cover 112 does not need to be connected to the first pole column 12, the strength requirements of the casing cover 112 are relatively low, and its thickness may be less than that of the first wall portion 1112. In this way, material can be saved. Similarly, if the outer contour dimensions of the casing 11 are fixed, the relatively small thickness of the casing cover 112 allows for an increase in the space within the casing 11. In this case, the casing 11 can accommodate a larger active material coated portion 21, which is advantageous for improving the energy density of the battery cell 10.

[0367] In some embodiments, the thickness of the casing cover 112 is greater than the thickness of other wall portions 1111 adjacent to the casing cover 112, excluding the first wall portion 1112.

[0368] For example, in this embodiment, the casing cover 112 can be welded to the casing body 111, and the thickness of the casing cover 112 may be greater than the thickness of the wall portion 1111 welded to the casing cover 112. Considering that the casing cover 112 needs to seal the opening 111a, it is necessary to provide adequate strength. Therefore, by setting the thickness of the casing cover 112 to be greater than the thickness of other wall portions 1111 adjacent to the casing cover 112 other than the first wall portion 1112, the overall strength of the casing 11 is relatively improved after the casing cover 112 seals the opening 111a, reducing the probability of the casing 11 failing and improving the reliability of the battery cell 10.

[0369] It should be explained that the thickness of the first wall portion 1112 described above may refer to the average thickness of the main structure of the first wall portion 1112. For example, the first wall portion 1112 may be stepped and have multiple regions of different thicknesses. In this case, the thickness of the first wall portion 1112 may refer to the thickness of the region riveted to the first pole column 12. Similarly, the thickness of the casing cover 112 may refer to the average thickness of the main structure of the casing cover 112, and the thickness of the wall portion 1111 may refer to the average thickness of the main structure of the wall portion 1111.

[0370] When Figure 5 is combined, in several embodiments, the thickness of the casing cover 112 is e3, where 1.0 mm ≤ e3 ≤ 1.5 mm. In other words, if e3 is less than 1.0 mm, the thickness of the casing cover 112 is relatively small, resulting in insufficient strength, lower strength of the casing 11, and making the casing 11 prone to breakage. If e3 is greater than 1.5 mm, the thickness of the casing cover 112 is too large, resulting in a relatively thick casing body 111, increasing the amount of material used and consequently increasing costs. If the outer contour dimensions of the casing body 111 are fixed, this reduces the internal space of the casing body 111, consequently reducing the dimensions of the active material coated area 21 and lowering the energy density of the battery cell 10.

[0371] In some embodiments, 1.2 mm ≤ e3 ≤ 1.4 mm. That is, the value of e3 must satisfy a certain safety margin. If the value of e3 is less than 1.2 mm, the thickness of the casing cover 112 is relatively small. In this case, the thickness of the casing cover 112 can meet the strength requirements, but the probability of the casing cover 112 being damaged unexpectedly during prolonged operation is relatively high. At the same time, the thickness of the casing cover 112 is too small, the requirements for the processing process are relatively high, and costs increase. If e3 is greater than 1.4 mm, the thickness of the casing cover 112 is relatively large, even if the thickness of the casing cover 112 meets the strength requirements, which increases the amount of material used and costs. If the outer contour dimensions of the casing body 111 are fixed, the internal space of the casing body 111 is relatively small, which reduces the dimensions of the active material coated area 21 and lowers the energy density of the battery cell 10. By setting e3 within the range of 1.2 mm or more and 1.4 mm or less, it is possible to satisfy both the strength requirements and the volume ratio requirements.

[0372] Combining Figures 4 and 5, in some embodiments, the opening 111a is provided at the bottom of the casing body 111.

[0373] In related technologies, the opening of the casing body is located at the top, and the casing cover is attached to the opening at the top of the casing body. When processing the casing body of this structure, a chamfer remains at the bottom of the internal space of the casing body. When attaching the active material coating section to the casing, because of the presence of the chamfer, the bottom of the active material coating section (which may refer to one end of the active material coating section away from the conductive part) does not come into contact with the chamfer inside the casing body, leaving a certain space between them. A partition wall is installed in this space, separating the active material coating section from the casing cover, resulting in wasted space inside the casing body. In this invention, since the opening 111a is provided at the bottom of the casing body 111 and the first pole column 12 is riveted to the casing body 111, in such a casing 11 structure, after the active material coated portion 21 enters the casing, there is no machined chamfer between the bottom of the active material coated portion 21 and the casing cover 112, and a partition wall can be omitted between the bottom of the active material coated portion 21 and the casing cover 112, reducing the gap between the bottom of the active material coated portion 21 and the casing cover 112, increasing the dimensions of the active material coated portion 21, and improving the energy density of the battery cell 10. Furthermore, since there is no machined chamfer near the bottom of the active material coated portion 21, the active material coated portion 21 will not be damaged by contact with a machined chamfer, that is, the probability of damage to the active material coated portion 21 can be reduced, the outflow of the active material coating layer can be reduced, the performance of the battery cell 10 can be improved, and at the same time, the occurrence of stress concentration in the active material coated portion 21 can be reduced.

[0374] On the other hand, since the casing cover 112 is installed at the bottom of the casing body 111, when the battery cell 10 constitutes the battery 100, it is generally necessary to fix the bottom of the casing 11 to the bottom of the battery case 20. In this case, when vibration occurs during use, the casing cover 112 is connected to the bottom of the case 20, so the amplitude received at the connection between the casing cover 112 and the casing body 111 is relatively small, further reducing the probability of the casing cover 112 and the casing body 111 cracking.

[0375] Referring to Figure 5, in some embodiments, the active material coated portion 21 has a first end face 21a adjacent to the casing cover 112, and the battery cell 10 further includes an inner insulating member 4 covering the battery core assembly 2, at least a portion of the inner insulating member 4 being provided between the first end face 21a and the casing cover 112, and the inner insulating member 4 having opposing first surfaces 4a and second surfaces 4b, the first surface 4a in contact with the first end face 21a and the second surface 4b in contact with the casing cover 112.

[0376] Referring to the description of the inner insulating member 4 in the preamble, if the insulating effect between the active material coated portion 21 and the casing cover 112 is satisfied by bringing the first surface 4a of the inner insulating member 4 into contact with the first end face 21a and the second surface 4b into contact with the casing cover 112, then it is possible to omit the installation of a partition wall between the active material coated portion and the casing cover, which is advantageous in saving space within the casing body 111, increasing the dimensions of the active material coated portion 21, and further improving the energy density of the battery cell 10.

[0377] In some embodiments, as shown in Figure 5, the thickness of the portion of the inner insulating member 4 located between the first surface 4a and the second surface 4b is d2, and of which 0 <d2≦0.1mmである。

[0378] That is, d2 may be 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, etc. When the thickness of the portion located between the first surface 4a and the second surface 4b of the inner insulating member 4 is greater than 0.1 mm, while satisfying the insulation effect between the active material coating portion 21 and the casing cover 112, due to the relatively large thickness of the inner insulating member 4, it can occupy the space within the casing body 111, which is disadvantageous for increasing the dimensions of the active material coating portion 21. When the thickness of the portion located between the first surface 4a and the second surface 4b of the inner insulating member 4 is less than 0.1 mm, in this way, it can satisfy the insulation requirements between the active material coating portion 21 and the casing cover 112, and at the same time, it is also advantageous for saving space, and thus advantageous for increasing the dimensions of the active material coating portion 21, and further improving the energy density of the battery cell 10.

[0379] In some embodiments, 0.02 mm < d2 ≤ 0.05 mm. That is, d2 may specifically be 0.02 mm, 0.025 mm, 0.03 mm, 0.035 mm, 0.04 mm, 0.045 mm, 0.05 mm, etc.

[0380] In the above technical solution, the value of d2 should have a certain safety margin. That is, it is necessary to select an appropriate range for d2. When d2 is greater than 0.05 mm, its insulation effect may exceed the requirements between the active material coating portion 21 and the casing cover 112, and the space within the casing body 111 is wasted. When d2 is less than 0.02 mm, the inner insulating member 4 can satisfy the insulation requirements between the active material coating portion 21 and the casing cover 112, but due to the thickness being too small, it will increase the difficulty of the manufacturing process of the inner insulating member 4, thereby increasing the cost, being prone to damage during the installation process, increasing the difficulty of assembly, and reducing the product yield. Therefore, by installing d2 within the range of 0.02 mm or more and 0.05 mm or less, it can satisfy the insulation requirements between the active material coating portion 21 and the casing cover 112, and at the same time, it can also balance the cost and the difficulty of assembly.

[0381] In some embodiments, as shown in Figure 4, the casing body 111 has a first wall portion 1112 facing the casing cover 112, and the first pole column 12 is provided on the first wall portion 1112.

[0382] In this proposed technology, the battery core assembly 2 can be inserted through the opening 111a, and the conductive portion 22 directly faces the first pole column 12, thereby allowing the conductive portion 22 to be connected to the first pole column 12 relatively easily and improving the assembly efficiency of the battery cell 10.

[0383] For example, the first wall portion 1112 and the casing cover 112 can be positioned at both ends in the third direction in Figure 3, and as in the embodiment described above, the opening 111a is provided at the bottom of the casing body 111, the casing cover 112 is provided at the bottom of the casing body 111, the battery core assembly 2 can be installed inside the casing body 111 from bottom to top along the third direction, and the conductive portion 22 can be easily connected to the first pole column 12.

[0384] Referring to Figure 56, in some embodiments of the present invention, a liquid storage groove 112a is provided on the end face of the casing cover 112 that is close to the inside of the casing body 111. The liquid storage groove 112a is used to store electrolyte, which can increase the electrolyte content inside the battery cell 10 and, consequently, extend the cycle life of the battery cell 10.

[0385] Referring to Figure 56, in some embodiments of the present application, the liquid storage groove 112a includes a first groove 1121 extending along the longitudinal direction of the casing cover 112. By maintaining that the direction of extension of the first groove 1121 coincides with the longitudinal direction of the casing cover 112, the volume of the first groove 1121 can be increased to store more electrolyte.

[0386] Referring to Figure 56, in some embodiments of the present application, the liquid storage groove 112a further includes a second groove 1122 that communicates with the first groove 1121 and extends along the width direction of the casing cover 112. By adding the second groove 1122 on top of the already installed first groove 1121, more electrolyte can be stored.

[0387] Referring to Figure 56, second grooves 1122 are selectively provided on both sides of the length of the first groove 1121, and the capacity of the liquid storage groove 112a can be increased by increasing the number of second grooves 1122. For example, two second grooves 1122 are provided on each side of the length of the first groove 1121. Of course, this is merely an example, and the number of second grooves 1122 is not limited to this, and further explanation is omitted here.

[0388] Referring to Figure 56, in some embodiments of the present application, the liquid storage groove 112a further includes third grooves 1123 located at both ends of the first groove 1121 and directed toward the corners of the casing cover 112. By adding the third grooves 1123 in addition to the first grooves 1121 and the second grooves 1122 already in place, the electrolyte storage capacity can be further increased.

[0389] Referring to Figure 56, a third groove 1123 is selectively provided on both sides of the first groove 1121 in the longitudinal direction. By increasing the number of third grooves 1123, the capacity of the liquid storage groove 112a can be increased. For example, two third grooves 1123 are provided on each side of the first groove 1121 in the longitudinal direction. Of course, this is merely an example, and the number of third grooves 1123 is not limited to this, and further explanation is omitted here.

[0390] Referring to Figure 5, in some embodiments of the present application, a protrusion 112b is provided on the end face of the casing cover 112 that is close to the inside of the casing body 111, and the circumferential end face of the protrusion 112b is in contact with the inner wall surface of the casing body 111.

[0391] The "protrusion 112b" may refer to a structure that protrudes from the casing cover 112, and the protrusion 112b may include, but is not limited to, a boss structure and an annular track structure, and can be specifically installed as needed.

[0392] In the above solution, the end face of the casing cover 112 that is close to the casing body 111 contacts the casing body 111, and the protrusion 112b is fitted into the inner wall surface of the casing body 111. This configuration makes the connection between the casing cover 112 and the casing body 111 tighter and more secure, strengthening the connection between the casing cover 112 and the casing body 111. At the same time, it is advantageous to reduce the thickness of the casing cover 112, thereby reducing the overall volume of the battery cell 10 and improving the energy density of the battery.

[0393] In some embodiments of the present invention, a protrusion 112b is provided in a portion of the end face of the casing cover 112 that is close to the inside of the casing body 111, and a liquid storage groove 112a is provided in another portion of the end face. For example, the protrusion 112b is rectangular and annular, and the liquid storage groove 112a is located in the middle of the rectangular annular shape.

[0394] In some embodiments of the present application, the protrusion 112b can be configured in a flat plate shape, and a step is formed between it and the edge of the casing cover 112, and the liquid storage groove 112a is formed in the protrusion 112b (see Figure 56).

[0395] In some embodiments of the present application, the casing cover 112 and the casing body 111 may be connected by welding or adhesive bonding.

[0396] According to some embodiments of the present application, the present application further provides a battery 100 including a battery cell 10 in any one of the above embodiments.

[0397] In the above proposed technology, since the first poles 12 of any adjacent battery cells 10 are connected to each other in the battery 100, when the battery 100 vibrates or deforms, the first poles 12 between any adjacent battery cells 10 are pulled towards each other. In this case, since the first poles 12 are installed in the casing body 111, the force acting on the first poles 12 is not directly acted on the casing cover 112, but is preferentially transmitted to the casing body 111. On the one hand, the distance over which the force is transmitted to the connection point between the casing body 111 and the casing cover 112 can be extended. On the other hand, when a force is applied, the casing body 111 preferentially deforms to reduce the force received at the connection point between the casing body 111 and the casing cover 112. This effectively reduces the probability of cracks occurring between the casing cover 111 and the casing body 112 during the battery 100's use, thereby improving the reliability of the battery cells 10.

[0398] According to several embodiments of the present application, the present application further provides an electrical device 1000 comprising a battery cell 10 in any one of the above embodiments, or a battery 100 in any one of the above embodiments. The battery cell 10 or battery 100 is used to provide electrical energy to the electrical device 1000.

[0399] In the above proposed technology, the electrical device 1000 uses the battery 100 or battery cell 10, and the probability of cracks occurring between the casing cover 112 and the casing body 111 of the battery cell 10 during use is relatively low, which is advantageous in improving the reliability of the battery 100 and improving the performance of the electrical device 1000.

[0400] In a fourth aspect, an embodiment of the present application further provides a method for assembling a battery cell 10, comprising a casing assembly 1 including a casing 11 and a first pole column 12, and a battery core assembly 2 including an active material coated portion 21 and a conductive portion 22, wherein the casing 11 includes a casing body 111 and a casing cover 112.

[0401] As shown in Figure 61, the assembly method includes: incorporating the battery core assembly 2 into the casing body 111; overlapping the conductive part 22 with the first pole post 12; welding the conductive part 22 to the first pole post 12 from the outside of the casing body 111; and covering the casing body 111 with the casing cover 112.

[0402] When the battery cell 10 of this invention is assembled, only the battery core assembly 2 is placed in the casing. In this way, the number of components placed in the casing is relatively small, and the weight is relatively light (in related technologies, the battery core assembly, casing cover, and poles must be assembled beforehand before being placed in the casing). Therefore, the operation of placing the battery core assembly 2 into the casing is relatively easy, and it is also easy to overlap the conductive part 22 with the first pole 12, resulting in relatively high assembly efficiency. Because the internal space of the casing body 111 is limited, welding the conductive part 22 to the first pole 12 from the outside of the casing body 111 facilitates the welding work and improves assembly efficiency. Welding from the outside effectively prevents metal foreign matter generated during the welding process from entering the inside of the battery cell, reducing the possibility of short circuits inside the battery cell due to metal foreign matter, and also facilitating the removal of metal foreign matter generated during the welding process. Finally, the assembly is completed by covering the casing body 111 with the casing cover 112.

[0403] Next, the assembly method of the present invention can complete the assembly of the battery cell 10 by only using the following steps: incorporating the battery core assembly 2 into the casing body 111, overlapping the conductive part 22 with the first pole post 12, welding the conductive part 22 to the first pole post 12 from the outside of the casing body 111, and covering the casing body 111 with the casing cover 112. This has the advantage of reducing the overall assembly steps, simplifying the assembly process, shortening the assembly time, and ultimately reducing the manufacturing cost of the battery cell 10.

[0404] In some embodiments, as shown in Figure 62, the battery cell 10 further includes a support 3 having a casing-in guide surface 35 on its edge, and the step of assembling the battery core assembly 2 into the casing body 111 includes mounting the support 3 on the side of the active material coating 21 closest to the first pole column 12 such that the casing-in guide surface 35 is positioned on the side of the support 3 away from the active material coating 21, and assembling the battery core assembly 2 into the casing body 111 according to the guide of the casing-in guide surface 35.

[0405] In this proposed technology, during assembly, the support 3 and the battery core assembly 2 can be pre-assembled before being incorporated into the casing 11. During incorporation, the support 3 is positioned at the front end of the active material coating section 21, meaning that the support 3 enters the casing 11 before the active material coating section 21. This reduces the difficulty of the support 3 entering the casing 11 using the casing entry guide surface 35, and also provides protection for the active material coating section 21, reducing the probability of scratches between the active material coating section 21 and the casing 11, thereby improving assembly efficiency and product yield. Furthermore, the contact area between the support 3 and the active material coating section 21 can be increased, mitigating stress concentration problems and allowing for the omission of other structural components.

[0406] In some embodiments, as shown in Figure 63, the battery cell 10 further includes a support 3 having a relief hole 31, and the step of overlapping the conductive portion 22 with the first pole post 12 includes the conductive portion 22 passing through the relief hole 31 and overlapping the conductive portion 22 with the first pole post 12.

[0407] The support 3 separates the active material coated section 21 from the casing 11, which is advantageous in improving the reliability of the battery cell 10. Furthermore, the provision of a relief hole 31 in the support 3 guides and restrains the conductive section 22 from fitting onto the first pole post 12 by passing through the relief hole 31. This eliminates the need to route the conductive section 22 away from the edge of the support 3 to approach the first pole post 12 during the assembly process of the battery cell 10. This simplifies the placement of the conductive section 22, saves material for the conductive section 22, and reduces costs. Moreover, the support 3 supports and guides the conductive section 22 to fitting onto the first pole post 12, reducing the risk of short-circuit connection between the conductive section 22 and the active material coated section 21, and further improving the reliability of the battery cell 10.

[0408] In some embodiments, as shown in Figure 64, the first pole column 12 has a first housing groove 12110, the surface of the first pole column 12 facing the active material coated portion 21 is the inner end face 122 of the pole column, the groove opening of the first housing groove 12110 is formed on the inner end face 122 of the pole column, and the step of overlapping the conductive portion 22 and the first pole column 12 includes extending the conductive portion 22 into the first housing groove 12110 and overlapping the conductive portion 22 with the groove walls of the first housing groove 12110.

[0409] In other words, in the process of overlapping the conductive part 22 with the first pole column 12, the first pole column 12 has a first housing groove 12110, which makes it relatively easy for the conductive part 22 to align with the first pole column 12. In this way, when welding the conductive part 22 to the first pole column 12 from outside the casing body 111, the stability of the conductive part 22 on the first pole column 12 can be improved, the welding quality can be improved, and this is advantageous in improving the performance of the battery cell 10.

[0410] In some embodiments, as shown in Figure 65, the first pole column 12 has a second housing groove 12120, the surface of the first pole column 12 away from the active material coated portion 21 is the pole column outer end face 123, the groove opening of the second housing groove 12120 is formed on the pole column outer end face 123, the second housing groove 12120 communicates with the inside of the casing 11 through a first through hole 12130, and the step of overlapping the conductive portion 22 and the first pole column 12 includes passing the conductive portion 22 through the first through hole 12130 and housing at least a portion of it in the second housing groove 12120, and overlapping the conductive portion 22 with the groove wall of the second housing groove 12120 and / or the hole wall of the first through hole 12130.

[0411] In the above proposed technology, the second housing groove 12120 allows the portion where the conductive part 22 and the first pole column 12 overlap to be exposed to the outside of the casing 11. In this way, welding the conductive part 22 and the first pole column 12 from the outside is made easier, the operation is relatively simple, and it is advantageous in improving assembly efficiency.

[0412] In some embodiments, as shown in Figure 66, the battery cell 10 further includes a first cover plate 13, and after welding the conductive portion 22 to the first pole post 12, the assembly method further includes welding the first cover plate 13 to the first pole post 12 so as to seal the groove opening of the second housing groove 12120.

[0413] In the above proposed technology, by installing the first cover plate 13 so as to seal the groove opening of the second housing groove 12120, leakage of the electrolyte from the casing 11 through the groove opening of the second housing groove 12120 can be prevented. Furthermore, since the first cover plate 13 seals the groove opening of the second housing groove 12120 and is electrically connected to the first pole column 12, an indirect electrical connection between the first pole column 12 and the bus member can be easily achieved using the first cover plate 13, which is advantageous in increasing the connection area of ​​the electrical connection point and reducing the resistance of the electrical connection point. In addition, the first cover plate 13 can separate the weld between the conductive part 22 and the first pole column 12 from the weld between the first pole column 12 and the bus member, reducing the influence of the weld between the conductive part 22 and the first pole column 12 on the weld between the first pole column 12 and the bus member, and improving the welding quality of the first pole column 12 and the bus member.

[0414] As long as there is no contradiction, the embodiments and features of the embodiments of this application can be combined with each other.

[0415] The foregoing are merely preferred embodiments of the present application and do not limit it, and various modifications and changes are possible for those skilled in the art. Any modifications, equivalent substitutions, and improvements made without departing from the spirit and principles of the present application are also included in the claims. [Explanation of Symbols]

[0416] Electrical device 1000, battery 100, controller 200, motor 300, First direction Z, second direction X, third direction Y, Axial radius R of the first pole column, Battery cell 10, case 20, first case 201, second case 202, Casing assembly 1, Casing 11, first wall surface 110, casing body 111, opening 111a, wall portion 1111, first wall portion 1112, second wall portion 1113, third wall portion 1114, wall portion 1115, first setting wall portion 1116, casing cover 112, liquid storage groove 112a, first groove portion 1121, second groove portion 1122, third groove portion 1123, protrusion 112b, mounting hole 113, The first pole 12, Storage section 121, First receiving groove 12110, first end wall 12111, first recessed groove 12112, first side wall 12113, Second receiving groove 12120, second end wall 12121, second recessed groove 12122, second side wall 12123, First groove step 12124, second groove step 12125, guide slope 12126, stair surface 12127, First through hole 12130, third accommodating groove 12140, fourth accommodating groove 12150, Second through hole 12160, third through hole 12170, pole column inner end face 122, pole column outer end face 123, First pole column section 124, second pole column section 125, First groove 126, spacing portion 127, Stopper part 1281, drilling part 1282, flange part 1283, Part 1, 1291; Part 2, 1292; First cover plate 13, first conductive member 131, second groove 1311, second conductive member 132, stress relief groove 133, Second cover plate 14, second pole column 15, pressure release section 16, relief groove 18, First sealing pad 191, second sealing pad 192, Battery core assembly 2, electrode assembly 2a, Active material coated portion 21, first end face 21a, current collector 211, active material layer 212, conductive portion 22 Tab section 221, tab sheet 2211, first convergence section 2212, second convergence section 2213, adapter sheet 222, Support 3, escape hole 31, first hole step 311, second hole step 312, Guide section 32, first support 33, second support 34, casing-enclosed guide surface 35, Main body portion 36, extended portion 37, third recessed groove 38, positioning groove 39, Inner insulating member 4, main body 41, connecting part 42, first surface 4a, second surface 4b, Sealing member 6, groove cover 7.

Claims

1. It is a battery cell, A casing assembly (1) comprising a casing (11) and a first pole column (12), wherein the casing (11) comprises a casing body (111) and a casing cover (112), the casing body (111) having an opening (111a), the casing cover (112) covering the opening (111a), and the first pole column (12) being installed in the casing body (111), A battery core assembly (2) including an active material coated portion (21) and a conductive portion (22), wherein the active material coated portion (21) is housed within the casing body (111) and the conductive portion (22) is electrically connected to the active material coated portion (21) and the first pole column (12), Battery cell.

2. A housing section (121) is provided on the first pole column (12), and at least a portion of the conductive part (22) is housed within the housing section (121). The battery cell according to claim 1.

3. The housing portion (121) has a first housing groove (12110), the surface of the first pole column (12) facing the active material coated portion (21) is the inner end face (122) of the pole column, the groove opening of the first housing groove (12110) is formed on the inner end face (122) of the pole column, and at least a portion of the conductive portion (22) is housed in the first housing groove (12110). The battery cell according to claim 2.

4. The casing (11) has a mounting hole (113), the first pole post (12) is attached to the mounting hole (113), and along the axial direction of the first pole post (12), the depth H1 of the first housing groove (12110) is greater than or equal to the minimum distance H2 from the inner end face (122) of the pole post to the mounting hole (113). The battery cell according to claim 3.

5. The housing portion (121) 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 to form the first housing groove (12110), and the electrical connection position between the conductive portion (22) and the first pole column (12) being located on the first end wall (12111) and / or the first side wall (12113). The battery cell according to claim 3.

6. 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). The battery cell according to claim 5.

7. The first pole column (12) has a first groove (126), the surface of the first pole column (12) away from the active material coated portion (21) is the pole column outer end surface (123), and the groove opening of the first groove (126) is formed on the pole column outer end surface (123). The battery cell according to claim 3.

8. The casing assembly (1) further includes a groove cover (7) provided on the first pole column (12) and sealing the groove opening of the first recessed groove (126). The battery cell according to claim 7.

9. The housing portion (121) has a second housing groove (12120), the surface of the first pole column (12) away from the active material coated portion (21) is the outer end surface (123) of the pole column, the groove opening of the second housing groove (12120) is formed on the outer end surface (123) of the pole column, the second housing groove (12120) communicates with the inside of the casing (11) via a first through hole (12130), the conductive portion (22) is drilled in the first through hole (12130) and at least a part of it is housed in the second housing groove (12120). The battery cell according to claim 2.

10. The electrical connection point between the conductive portion (22) and the first pole column (12) is located on the wall of the first through hole (12130) in which the housing portion (121) is formed. The battery cell according to claim 9.

11. The housing portion (121) 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 active material coated portion (21), the second end wall (12121) and the second side wall (12123) surround each other to form the second housing 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 first pole column (12) is located in the second end wall (12121) and / or the second side wall (12123). The battery cell according to claim 9.

12. 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). The battery cell according to claim 11.

13. The casing (11) has a mounting hole (113), the first pole post (12) is attached to the mounting hole (113), and along the axial direction of the first pole post (12), the depth H3 of the second housing groove (12120) is greater than or equal to the minimum distance H4 from the outer end face (123) of the pole post to the mounting hole (113). The battery cell according to claim 9.

14. The casing assembly (1) further includes a first cover plate (13) which is fitted onto the first pole post (12) and seals the groove opening of the second housing groove (12120), the first cover plate (13) being electrically connected to the first pole post (12). The battery cell according to claim 9.

15. 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 onto the first pole post (12) and electrically connected, and the second conductive member (132) is fitted onto the first conductive member (131) and electrically connected. The battery cell according to claim 14.

16. 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 housing groove (12120) such that the second conductive member (132) is exposed from the groove opening of the second groove (1311). The battery cell according to claim 15.

17. The first cover plate (13) is fitted into the groove opening of the second housing groove (12120). The battery cell according to claim 14.

18. The wall surface formed at the groove opening of the second housing groove (12120) of the first pole column (12) is a guide slope (12126), and the guide slope (12126) is used to guide the first cover plate (13) so that it fits into the groove opening of the second housing groove (12120). The battery cell according to claim 17.

19. The second housing groove (12120) includes a first groove step (12124) and a second groove step (12125) on the side of the first groove step (12124) that is close to the outer end surface (123) of the pole column, and the cross-sectional area of ​​the second groove step (12125) is 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 by the stepped surface (12127). The battery cell according to claim 17.

20. The first pole column (12) includes a first pole column portion (124) and a second pole column portion (125) made of different materials and electrically connected, the second pole column portion (125) is located on the side of the first pole column portion (124) away from the active material coated portion (21), the housing portion (121) is installed on the first pole column portion (124), or installed on the first pole column portion (124) and the second pole column portion (125), and the conductive portion (22) is electrically connected to the first pole column portion (124). The battery cell according to claim 2.

21. The housing portion (121) has a fourth housing groove (12150), the surface of the first pole post (12) away from the active material coated portion (21) is the outer end face (123) of the pole post, the groove opening of the fourth housing groove (12150) is formed on the outer end face (123) of the pole post, the fourth housing groove (12150) communicates with the inside of the casing (11) via a 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 first pole post (12) is located on the hole wall of the second through hole (12160) in which the housing portion (121) is formed. The battery cell according to claim 2.

22. The present invention further includes a support (3) located within the casing (11) and on the side of the active material coated portion (21) that is close to the first pole column (12), wherein the support (3) has a relief hole (31) to avoid the conductive portion (22), and the conductive portion (22) is adapted to extend through the relief hole (31) toward the side of the support (3) away from the active material coated portion (21). The battery cell according to claim 2.

23. The support (3) is provided with a guide portion (32) formed by surrounding at least a part of the relief hole (31), and at least a part of the guide portion (32) extends to the housing portion (121). The battery cell according to claim 22.

24. The edge of the support (3) opposite to the casing cover (112) has a casing-receiving guide surface (35) which includes an arcuate surface and / or an inclined surface. The battery cell according to claim 23.

25. The support (3) is a single integrated structure, or the support (3) is a separate structure and includes a removable first support (33) and a second support (34), with the relief hole (31) defined between the first support (33) and the second support (34). The battery cell according to claim 22.

26. The casing (11) is located inside the inner insulating member (4), which encloses the outside of the active material coated portion (21) and is connected to the support (3), The battery cell according to claim 22.

27. The casing assembly (1) includes the first pole post (12) which is riveted to at least one of the casing bodies (111). The battery cell according to claim 1.

28. The casing body (111) is provided with mounting holes (113), and the first pole column (12) includes an integrally molded pole column body, a first position limiting base and a second position limiting base, the pole column body is drilled in the mounting holes (113), and the first position limiting base and the second position limiting base are installed at both ends of the pole column body along the axial direction of the mounting holes (113) so as to rivet the first pole column (12) to the casing body (111), the first position limiting base is fitted to the outside of the casing body (111) in a position limiting manner, and the second position limiting base is fitted to the inside of the casing body (111) in a position limiting manner. The battery cell according to claim 26.

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

30. The casing body (111) has a second wall portion (1113) and a third wall portion (1114) installed opposite each other, and each of the second wall portion (1113) and the third wall portion (1114) is provided with at least one of the first pole columns (12). The battery cell according to claim 1.

31. The casing body (111) has a plurality of wall portions (1111), a portion of which is a first setting wall portion (1116), the area of ​​which is which is larger than the area of ​​which is which is which, and the first pole column (12) is provided on the first setting wall portion (1116). The battery cell according to claim 1.

32. The casing body (111) has a plurality of wall portions (1111), at least one of the plurality of wall portions (1111) is a second setting wall portion, the battery cell further includes a pressure release portion (16) provided in the second setting wall portion, and the first pole column (12) is provided in the other wall portions (1111) other than the second setting wall portion. The battery cell according to claim 1.

33. The battery cell (10) further includes a pressure release portion (16) provided on the casing cover (112) and integrally molded with the casing cover (112). The battery cell according to claim 1.

34. The casing body (111) has a plurality of wall portions (1111), at least one of the plurality of wall portions (1111) is a first wall portion (1112), the first pole column (12) is riveted to the first wall portion (1112), and the thickness of the first wall portion (1112) is greater than the thickness of the other wall portions (1111). The battery cell according to claim 1.

35. The thickness of the casing cover (112) is less than the thickness of the first wall portion (1112). The battery cell according to claim 34.

36. The thickness of the casing cover (112) is greater than the thickness of the other wall portions (1111) that are adjacent to the casing cover (112) and other than the first wall portion (1112). The battery cell according to claim 35.

37. The opening (111a) is provided at the bottom of the casing body (111). The battery cell according to claim 1.

38. The active material coated portion (21) has a first end face (21a) adjacent to the casing cover (112), the battery cell further includes an inner insulating member (4) covering the battery core assembly (2), at least a portion of the inner insulating member (4) is provided between the first end face (21a) and the casing cover (112), the inner insulating member (4) has opposing first surfaces (4a) and second surfaces (4b), the first surface (4a) is in contact with the first end face (21a) and the second surface (4b) is in contact with the casing cover (112), The battery cell according to claim 37.

39. The casing body (111) has a first wall portion (1112) facing the casing cover (112), and the first pole column (12) is provided on the first wall portion (1112). The battery cell according to claim 1.

40. A battery comprising a battery cell (10) according to any one of claims 1 to 39.

41. An electrical device comprising a battery (100) as described in claim 40.

42. A method for assembling battery cells, The battery cell (10) includes a casing assembly (1) including a casing (11) and a first pole (12), and a battery core assembly (2) including an active material coated portion (21) and a conductive portion (22), wherein the casing (11) includes a casing body (111) on which the first pole (12) is installed and a casing cover (112), The aforementioned assembly method The battery core assembly (2) is incorporated into the casing body (111), The conductive part (22) and the first pole column (12) are superimposed, The conductive portion (22) is welded to the first pole column (12) from outside the casing body (111), This includes covering the casing body (111) with the casing cover (112), Assembly method.

43. The battery cell further includes a support (3) whose edge has a casing-enclosed guide surface (35), The step of incorporating the battery core assembly (2) into the casing body (111) is as follows: The support (3) is attached to the side of the active material coating portion (21) that is close to the first pole column (12), such that the casing-enclosed guide surface (35) is positioned on the side of the support (3) that is away from the active material coating portion (21), This includes assembling the battery core assembly (2) into the casing body (111) according to the guide of the casing-enclosed guide surface (35), The assembly method according to claim 42.

44. The battery cell further includes a support (3) having a relief hole (31), The step of overlapping the conductive portion (22) and the first pole column (12) is, The conductive portion (22) penetrates the relief hole (31), This includes superimposing the conductive portion (22) and the first pole column (12), The assembly method according to claim 42.

45. The first pole column (12) has a first housing groove (12110), the surface of the first pole column (12) facing the active material coated portion (21) is the pole column inner end face (122), and the groove opening of the first housing groove (12110) is formed on the pole column inner end face (122). The step of overlapping the conductive portion (22) and the first pole column (12) is, The conductive portion (22) extends into the first housing groove (12110), This includes overlapping the conductive portion (22) with the groove wall of the first housing groove (12110), The assembly method according to claim 42.

46. The first pole column (12) has a second housing groove (12120), the surface of the first pole column (12) away from the active material coated portion (21) is the pole column outer end face (123), the groove opening of the second housing groove (12120) is formed on the pole column outer end face (123), and the second housing groove (12120) communicates with the inside of the casing (11) through the first through hole (12130). The step of overlapping the conductive portion (22) and the first pole column (12) is, The conductive portion (22) penetrates through the first through hole (12130) so that at least a portion of it is housed in the second housing groove (12120), This includes overlapping the conductive portion (22) with the groove wall of the second housing groove (12120) and / or the hole wall of the first through hole (12130), The assembly method according to claim 42.

47. The battery cell further includes a first cover plate (13), After welding the conductive part (22) to the first pole column (12), the assembly method is as follows: The present invention further includes welding the first cover plate (13) to the first pole column (12) so as to seal the opening of the second housing groove (12120), The assembly method according to claim 46.

Images