Battery cell, battery device, and electric device

Abstract

A battery cell, a battery device, and an electric device. The battery cell comprises: a casing (10), comprising an accommodating cavity (101) and mounting holes (111); pole components (20) each comprising a pole body (21), the pole bodies (21) being located at the mounting holes (111); electrode assemblies (30) each comprising an active material-coated portion (31) and a tab (33), the tab (33) being welded and connected to form a tab portion (331), and the end surface of the end of the tab portion (331) facing the corresponding pole component (20) being a first surface (3311); and adapter pieces (34) each connected between the corresponding tab portion (331) and the corresponding pole body (21), the side surface of each adapter piece (34) welded to the corresponding pole body (21) being a second surface (3401). In the radial direction of the mounting holes (111), the first surface (3311) is flush with the second surface (3401).

Description

Battery cells, battery packs and electrical devices

[0001] Cross-reference of related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 202510220727.9, filed on February 26, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, and in particular to a battery cell, a battery device, and an electrical device. Background Technology

[0004] In today's battery technology field, the design and manufacturing process of battery cells play a crucial role in battery performance. Currently, some battery cells use tab and adapter structures, which occupy a large amount of space and affect the energy density of the battery cell.

[0005] Application content

[0006] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes a battery cell, and a battery device and an electrical device including the battery cell, wherein the battery cell can reduce the space occupied by the adapter plate in the housing along the axial direction of the mounting hole, thereby increasing the energy density of the battery cell.

[0007] In a first aspect, embodiments of this application provide a battery cell, comprising: a housing having a receiving cavity, the housing including a mounting wall having a mounting hole; an electrode post component mounted on the mounting wall and including an electrode post body disposed at the mounting hole position; an electrode assembly disposed within the receiving cavity and including an active material coating portion and an electrode tab connected to the active material coating portion, the electrode tabs being welded together to form an electrode tab portion, the end face of the electrode tab portion facing the electrode post component being a first surface; and an adapter piece connected between the electrode tab portion and the electrode post body, the side surface of the adapter piece welded to the electrode post body being a second surface; wherein, in the radial direction of the mounting hole, the first surface and the second surface are flush.

[0008] In the above technical solution, since the first surface of the tab is flush with the second surface of the adapter, the adapter will not be arranged on the side of the tab facing the electrode body. In this way, the adapter does not need to occupy the space on the side of the tab facing the electrode body. As a result, the space occupied by the adapter in the housing along the mounting hole axis can be reduced, allowing the tab to have more bending space in the mounting hole axis, which facilitates the bending of the tab and reduces the probability of defects caused by bending. It can also provide more arrangement space for the active material coating part of the electrode assembly in the mounting hole axis, thereby improving the energy density of the battery cell.

[0009] In some embodiments, the electrode tab and the adapter piece are arranged sequentially in the radial direction of the mounting hole, and the electrode tab and the adapter piece are connected in the axial direction of the mounting hole.

[0010] In the above technical solution, by arranging the tabs and adapters radially in the mounting hole and connecting them axially in the mounting hole, it is possible not only to further reduce the space occupied by the adapters in the axial direction of the mounting hole, reduce tab bending defects, and improve the energy density of the battery cell, but also to increase the contact area between the tabs and the adapters, improve the connection strength and reliability between the tabs and the adapters, and improve conductivity.

[0011] In some embodiments, at least a portion of the end face of the tab facing the adapter piece in the radial direction of the mounting hole is formed as a first inclined surface, the first inclined surface being inclined relative to the thickness direction of the tab, and at least a portion of the surface of the adapter piece facing the tab is formed as a second inclined surface, the first inclined surface and the second inclined surface being fitted and connected.

[0012] In the above technical solution, by forming a first inclined surface on the end face of the tab and a second inclined surface on the end face of the adapter piece, and by fitting the first inclined surface and the second inclined surface together, the connection length between the tab and the adapter piece can be increased, the connection reliability between the tab and the adapter piece can be improved, the conductivity can be enhanced, the probability of the tab folding defect during the winding of the electrode assembly can be reduced, the energy density of the battery cell can be increased, and the adaptability to the thickness of the electrode assembly can be improved.

[0013] In some embodiments, the first inclined plane and the second inclined plane are planes.

[0014] In the above technical solution, the first and second inclined surfaces are planes, which can simplify the structure of the electrode lug and the adapter piece, facilitate the forming of the first and second inclined surfaces, reduce processing difficulty, and improve production efficiency.

[0015] In some embodiments, the angle between the first inclined surface and the second inclined surface and one side surface of the tab in the thickness direction is greater than or equal to 20° and less than or equal to 45°.

[0016] In the above technical solution, by setting the angle between either the first inclined surface or the second inclined surface and the first surface to be greater than or equal to 20° and less than or equal to 45°, it is not only convenient to form the first inclined surface and the second inclined surface, but also to further increase the length of the first inclined surface and the second inclined surface, increase the connection length between the adapter piece and the electrode lug, improve the ultrasonic welding quality between the first inclined surface and the second inclined surface, and improve the connection reliability and conductivity of the adapter piece and the electrode lug.

[0017] In some embodiments, the ratio of the length of the first inclined surface along the inclined direction to the thickness of the tab portion is greater than or equal to 2 and less than or equal to 3.

[0018] In the above technical solution, the ratio of the length of the first inclined surface to the thickness of the electrode tab is greater than or equal to 2 and less than or equal to 3, which facilitates the forming of the first inclined surface, increases the length of the first inclined surface, increases the connection length between the adapter piece and the electrode tab, and improves the connection reliability and conductivity between the adapter piece and the electrode tab.

[0019] In some embodiments, the length of the first inclined surface along the inclined direction is greater than or equal to 2 mm and less than or equal to 3 mm.

[0020] In the above technical solution, the length of the first inclined surface is greater than or equal to 2mm and less than or equal to 3mm. Increasing the length of the first inclined surface can increase the connection length between the adapter plate and the electrode tab, thereby improving the connection reliability between the adapter plate and the electrode tab.

[0021] In some embodiments, the total area of ​​the first inclined surface on the end face of the electrode facing the adapter plate is greater than or equal to 40 mm². 2 And less than or equal to 60mm 2 .

[0022] In the above technical solution, the total area of ​​the first inclined surface on the end face of the electrode facing the adapter plate is greater than or equal to 40mm². 2 And less than or equal to 60mm 2 This allows the tab to have sufficient contact area with the adapter plate, improving the reliability of the connection between the tab and the adapter plate.

[0023] In some embodiments, the distance between one end of the tab facing away from the adapter piece and the other end of the first inclined surface facing away from the adapter piece is a first distance, which is greater than or equal to 2 mm and less than or equal to 3 mm.

[0024] In the above technical solution, the distance between the end of the tab facing away from the adapter piece and the end of the first inclined surface facing away from the adapter piece is greater than or equal to 2mm and less than or equal to 3mm. This allows for sufficient press-fit length during welding of multiple tabs, ensuring effective welding, while further reducing the probability of tab folding defects and improving adaptability to electrode assembly thickness.

[0025] In some embodiments, the distance between the end edge of the tab away from the adapter piece and the end edge of the adapter piece away from the tab is a first dimension, which is less than or equal to 12 mm.

[0026] In the above technical solution, the distance between the end edge of the tab away from the adapter piece and the end edge of the adapter piece away from the tab is less than or equal to 12mm. This allows the length of the horizontal section of the conductive part to be adapted to the width of the pole post, facilitating the connection between the pole post and the horizontal section, improving connection reliability, reducing material usage, and reducing the space occupied in the housing.

[0027] In some embodiments, the first dimension is greater than or equal to 8 mm and less than or equal to 10 mm.

[0028] In the above technical solution, the first dimension is greater than or equal to 8mm and less than or equal to 10mm, which can make the horizontal section have sufficient length to realize the welding connection with the pole body, and reduce the probability that the welding position of the pole body and the adapter plate coincides with the welding position of the adapter plate and the pole ear, thereby improving the welding quality.

[0029] In some embodiments, the first dimension is less than or equal to 6 mm.

[0030] In the above technical solution, the first dimension is less than or equal to 6mm, which can make the length of the horizontal section of the conductive part match the width of the narrow electrode post. While achieving effective connection between the horizontal section and the electrode post body, the length of the horizontal section is reduced, the space occupied by the horizontal section in the casing is reduced, and the energy density of the battery cell is improved.

[0031] In some embodiments, the second bevel extends from one end of the adapter plate toward the tab to the other end away from the tab.

[0032] In the above technical solution, by extending the second inclined surface from one end of the adapter piece toward the electrode tab to the other end away from the electrode tab, the second inclined surface with the longest inclined surface size can be formed on the adapter piece of limited length, thereby increasing the connection length between the adapter piece and the electrode tab and improving the connection reliability between the adapter piece and the electrode tab.

[0033] In some embodiments, the number of first bevels is one, and the two ends of the first bevel in the radial direction of the mounting hole extend to the two side surfaces of the tab in the thickness direction.

[0034] In the above technical solution, the end face of the electrode tab facing the adapter plate is formed into a first inclined surface, which can simplify the end face structure of the electrode tab, facilitate molding, and also facilitate the bonding and welding of the first inclined surface with the adapter plate, reducing the welding difficulty.

[0035] In some embodiments, the end face of the tab facing the adapter plate has a plurality of first inclined surfaces, the plurality of first inclined surfaces are arranged along the thickness direction of the tab, and there are a plurality of second inclined surfaces, the plurality of second inclined surfaces and the plurality of first inclined surfaces are fitted one-to-one.

[0036] In the above technical solution, the end face of the electrode tab is formed with multiple first inclined surfaces, and the end face of the adapter piece is formed with multiple second inclined surfaces that correspond one-to-one with the multiple first inclined surfaces. This can increase the total inclined surface length of the multiple first inclined surfaces and the total inclined surface length of the multiple second inclined surfaces, thereby increasing the connection length and connection area between the adapter piece and the electrode tab, and improving the connection reliability and conductivity between the adapter piece and the electrode tab.

[0037] In some embodiments, a plurality of first inclined surfaces are sequentially connected in the thickness direction of the tab.

[0038] In the above technical solution, multiple first inclined surfaces are connected in sequence, which can increase the total inclined surface length of multiple first inclined surfaces and the total inclined surface length of multiple second inclined surfaces, increase the connection length and connection area between the adapter plate and the electrode lug, and improve the connection reliability between the adapter plate and the electrode lug.

[0039] In some embodiments, in the thickness direction of the tab, the inclination directions of two adjacent first slopes are opposite.

[0040] In the above technical solution, by setting the inclination directions of two adjacent first inclined surfaces to be opposite, the total inclined surface length of multiple first inclined surfaces and the total inclined surface length of multiple second inclined surfaces can be further increased, thereby increasing the connection length and connection area between the adapter plate and the electrode lug, and improving the connection reliability between the adapter plate and the electrode lug.

[0041] In some embodiments, the end face of the tab facing the adapter includes two first inclined surfaces, which extend toward each other or away from each other in the direction from the tab toward the adapter. In the axial direction of the mounting hole, adjacent ends of the two first inclined surfaces are directly connected. Alternatively, the end face of the tab facing the adapter further includes a connecting surface that extends along the axial direction of the mounting hole. In the axial direction of the mounting hole, adjacent ends of the two first inclined surfaces are connected by the connecting surface.

[0042] In the above technical solution, by having the tab have two first inclined surfaces extending toward or away from the adapter plate, and the adjacent ends of the two first inclined surfaces are directly connected or connected through a connecting surface, the end face structure of the tab and the adapter plate can be simplified and the production difficulty reduced, while further increasing the connection length and connection area between the tab and the adapter plate.

[0043] In some embodiments, the tab further includes a folding portion, which is connected between the tab portion and the active material coating portion, and is formed by folding together one end of a plurality of tab pieces connected to the active material coating portion.

[0044] In the above technical solution, the roots of multiple tabs adjacent to the active material coating are brought together to form a converged part, so that multiple tabs can be stacked and formed into a whole that is not easy to loosen, thereby facilitating the connection between the tab and the adapter and the electrode body.

[0045] In some embodiments, the adapter includes a first segment, a second segment, and a connecting segment. The first segment is located on the side of the tab away from the pole body and is connected to the tab. The second segment is arranged with the tab in the extending direction of the tab and is connected to the pole body. The surface of the second segment facing the pole body is formed as a second surface. The connecting segment connects the first segment and the second segment.

[0046] In the above technical solution, the adapter includes a first section and a second section that are offset from each other in the axial direction of the mounting hole, as well as a connecting section that connects the first section and the second section. Under the premise of achieving the overlapping connection between the first section and the electrode lug, it is convenient for the second section to be flush with the electrode lug, thereby reducing the space occupied, reducing the length of the electrode lug, and reducing the risk of the electrode lug folding defects.

[0047] In some embodiments, the adapter sheet includes a plurality of stacked and connected adapter foils to make the adapter sheet deformable.

[0048] In the above technical solution, since the thickness of the multiple transition foils is small, the multiple transition foils are equivalent to multiple thin plates. Compared with the one-piece molded transition sheet, the multiple transition foils can more easily form the second inclined surface, simplifying the processing.

[0049] In some embodiments, the tab is welded and / or bonded to the adapter plate, and the adapter plate is welded and / or bonded to the pole body.

[0050] In the above technical solution, the tabs, adapter pieces, and electrode post bodies are welded or bonded together, which can achieve an effective connection between the tabs, adapter pieces, and electrode post bodies and ensure the conductivity between the tabs, adapter pieces, and electrode post bodies.

[0051] In some embodiments, the pole member covers the mounting hole, and the edge of the pole member is supported on the side of the mounting wall away from or near the receiving cavity.

[0052] In the above technical solution, the terminal component is covered by the mounting hole, which can simplify the structure of the terminal component and improve the energy density of the battery cell. The edge of the terminal component is supported on the inner or outer side of the mounting wall, which can flexibly set the support position of the terminal component according to the performance requirements of the battery cell, simplify the connection structure between the terminal component and the mounting wall, and facilitate assembly.

[0053] In some embodiments, the pole piece further includes a transition structure and an insulating sealing structure, the transition structure surrounding the pole piece body and connected to the mounting wall, and the insulating sealing structure being insulating and sealingly fitted between the transition structure and the pole piece body.

[0054] In the above technical solution, by making the insulating and sealing structure of the terminal component insulated and sealed between the adapter structure and the terminal body, the terminal component itself can have self-sealing properties, which facilitates the installation and mating of the terminal component and the shell, saving installation time and cost. Since there is no need to consider insulation and sealing between the adapter structure and the mounting wall, only a reliable connection around the circumference is required. This can improve the stress deformation problem of the mounting wall, thereby helping to reduce the wall thickness of the mounting wall, reduce material costs, and reduce the weight of the battery cell, achieving lightweight production.

[0055] In some embodiments, the adapter structure is formed as an elongated strip extending along the length direction of the mounting wall, and the outline shape of the pole body matches the outline shape of the adapter structure; or, the adapter structure is formed as an elongated strip extending along the length direction of the mounting wall, and the pole body is located at the center of the length of the adapter structure and is circular.

[0056] In the above technical solution, by matching the contour shapes of the adapter structure and the electrode body, both being elongated, the area of ​​the electrode body can be increased, which is beneficial to increasing the connection area between the conductive part and the electrode body, thereby improving conductivity. By setting the adapter structure to be elongated and the electrode body to be circular, the connection area between the electrode body and the adapter structure can be reduced, improving the uniformity of stress at the connection point between the electrode body and the adapter structure.

[0057] In some embodiments, the insulating sealing structure includes a sealing structure member, at least a portion of which is clamped between the adapter structure and the pole body in the inward and outward directions of the mounting wall.

[0058] In the above technical solution, by setting at least a portion of the sealing structure between the adapter structure and the electrode body in the inward and outward directions of the mounting wall, an axial seal is achieved between the adapter structure and the electrode body. This axial seal provides a more reliable sealing effect and improves the electrolyte leakage problem at the mating point of the adapter structure and the electrode body. Furthermore, if the electrode component only includes the electrode body, and an axial seal is provided between the electrode body and the mounting wall, sealing pressure needs to be applied along the axial direction of the mounting hole, which would lead to excessive stress on the mounting wall. However, the embodiments of this application integrate the axial seal (such as the axial side portion) into the electrode component, reducing the axial force on the mounting wall, improving the reliability of the mounting wall, and allowing for a moderate reduction in the thickness of the mounting wall to lower costs and increase energy density.

[0059] In some embodiments, the insulating sealing structure includes a sealing structure member disposed around the periphery of the adapter structure near the pole body.

[0060] In the above technical solution, by placing the sealing structure in the inner ring of the adapter structure, the sealing structure can achieve a sealing effect throughout the entire circumference. Moreover, its position is close to the mating position between the adapter structure and the pole body, which facilitates sealing the mating position between the adapter structure and the pole body through a shorter path, improving the reliability of the seal. It also helps to reduce the size of the sealing structure, reduce the sealing area, and make it easier to achieve compression sealing, making the seal less prone to failure and improving the sealing effect.

[0061] In some embodiments, a first receiving groove communicating with the receiving cavity is formed at the electrode post component. The first receiving groove is open toward the receiving cavity and is at least partially surrounded by the electrode post component. The electrode tab and the adapter plate together constitute a conductive part connecting the electrode post body and the active material coating part. At least a portion of the conductive part is received in the first receiving groove.

[0062] In the above technical solution, by providing a first receiving groove to accommodate the conductive part, the space occupied by the conductive part in the receiving cavity can be reduced, allowing the receiving cavity to have a larger space to accommodate the active material coating part. This is beneficial for increasing the volume of the active material coating part, thereby increasing the energy density of the battery cell. Moreover, since the first receiving groove is open towards the electrode components, the conductive part can be easily inserted into the first receiving groove, reducing the difficulty of operation.

[0063] In some embodiments, the pole body is formed with a second receiving groove, which is open away from the receiving cavity.

[0064] In the above technical solution, the electrode body has a second receiving groove that is open to the opposite side of the receiving cavity, which can reduce the material used in the electrode body, reduce the cost, reduce the weight of the electrode body, and increase the energy density of the battery cell.

[0065] In some embodiments, the housing includes a body having an opening and a cover covering the opening, a mounting wall including a wall of the housing disposed opposite to the opening, and / or, the mounting wall including the cover.

[0066] In the above technical solution, the pole component can be located on the wall of the housing opposite to the opening, or the pole component can be located on the housing cover, which can realize the flexible setting of the pole component.

[0067] Secondly, embodiments of this application provide a battery device, the battery comprising a battery cell according to the second aspect of this application.

[0068] In the above embodiments, by setting the battery cell of the first aspect, the space occupied by the adapter piece in the housing along the mounting hole axis can be reduced, and more space can be provided for the active material coating part of the electrode assembly along the mounting hole axis, thereby improving the energy density of the battery cell and the energy density of the battery device.

[0069] Thirdly, embodiments of this application provide an electrical device, including a battery device according to the second aspect of this application.

[0070] In the above-described embodiments, by providing the battery device described in the second aspect, the overall performance of the power-consuming device is improved.

[0071] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0072] Figure 1 is a schematic diagram of a vehicle according to an embodiment of this application;

[0073] Figure 2 is an exploded view of a battery device according to an embodiment of this application;

[0074] Figure 3 is a schematic diagram of the structure of a battery cell according to an embodiment of this application;

[0075] Figure 4 is a partial structural cross-sectional view of a battery cell according to Embodiment 1 of this application;

[0076] Figure 5 is a schematic diagram of the structure of the electrode assembly and adapter plate shown in Figure 4;

[0077] Figure 6 is a schematic diagram of the structure of the electrode tab and the adapter plate in Figure 5;

[0078] Figure 7 is a partial structural cross-sectional view of a battery cell according to Embodiment 2 of this application;

[0079] Figure 8 is a schematic diagram of the structure of the electrode assembly and adapter plate shown in Figure 7;

[0080] Figure 9 is a cross-sectional view of the electrode assembly and adapter plate of a battery cell according to Embodiment 3 of this application;

[0081] Figure 10 is a structural cross-sectional view of the electrode assembly and adapter plate of a battery cell according to Embodiment 4 of this application;

[0082] Figure 11 is a partial structural cross-sectional view of a battery cell according to Embodiment 5 of this application;

[0083] Figure 12 is a schematic diagram of the structure of the electrode assembly and adapter plate shown in Figure 11;

[0084] Figure 13 is a partial structural cross-sectional view of a battery cell according to Embodiment Six of this application;

[0085] Figure 14 is a schematic diagram of the structure of the electrode assembly and adapter plate shown in Figure 13;

[0086] Figure 15 is a structural cross-sectional view of the electrode assembly and adapter plate of a battery cell according to Embodiment 7 of this application;

[0087] Figure 16 is a schematic diagram of the structure when the tabs of the battery cell shown in Figure 15 are straightened and welded to the adapter piece;

[0088] Figure 17 is a schematic diagram of the structure of the battery cell according to Embodiment 1 of this application when the tab and the adapter are straightened and welded together.

[0089] Figure 18 is a partial structural diagram of the battery cell with the tab and adapter in a straightened state according to Embodiment 1 of this application.

[0090] Figure 19 is a schematic diagram of the structure of the electrode assembly of the battery cell according to Embodiment 1 of this application installed in the housing;

[0091] Figure 20 is a partial structural schematic diagram of the connection between the adapter piece and the terminal component of the battery cell according to Embodiment 1 of this application.

[0092] Figure 21 is a partial structural schematic diagram of the connection between the terminal component and the housing of a battery cell according to Embodiment 1 of this application.

[0093] Reference numerals: 1. Electrical device; 1000. Battery; 2000. Controller; 3000. Motor; 400. Housing; 410. First housing; 420. Second housing; 411. Base plate; 100. Battery cell; F1. First direction; F2. Second direction; F1. Third direction; 10. Housing; 101. Receiving cavity; 11. Mounting wall; 111. Mounting hole; 12. Shell body; 20. Terminal component; 21. Terminal body; 22. Adapter structure; 23. Insulating and sealing structure; 30. Electrode assembly; 31. Active material coating part; 32. Conductive part; 33. Tab; 331. Tab part; 3311. First surface; 3312. First inclined surface; 332. Closing part; 34. Adapter plate; 3401. Second surface; 3402. Second inclined surface; 341. First section; 342. Second section; 343. Connecting section; 50. Pressure relief device; 60. Insulating bracket; 61. Through hole; 2. Welding device; 2A. Welding base; 2B. Welding head. Detailed Implementation

[0094] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0095] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0096] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0097] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0098] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0099] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two).

[0100] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0101] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0102] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include one or more battery cells; when there are multiple battery cells, they are connected in series, parallel, or mixed connection via a busbar. Mixed connection refers to multiple battery cells being connected in both series and parallel connections.

[0103] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form a single module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0104] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0105] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0106] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0107] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0108] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0109] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0110] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0111] The battery cells mentioned in the embodiments of this application may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application are not limited to these. Battery cells may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited to these shapes either. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this application are not limited to these types either.

[0112] For example, a single battery cell typically includes a housing, a cell assembly, and an electrolyte. The housing is used to house the cell assembly and the electrolyte, and the housing has at least one positive electrode post and at least one negative electrode post. The cell assembly includes one or more electrode assemblies, which are formed by stacking or winding positive electrode sheets, negative electrode sheets, and separators.

[0113] The positive electrode generally includes a positive current collector and a positive active material layer. The positive active material layer is directly or indirectly coated on the positive current collector. The positive current collector without the positive active material layer protrudes from the positive current collector with the positive active material layer. The positive current collector without the positive active material layer serves as a positive electrode tab. Multiple positive electrode tabs are stacked together and form an electrical connection with the positive electrode post. For example, the multiple stacked positive electrode tabs can be directly soldered to the positive electrode post to form an electrical connection; or, the battery cell assembly can also include a positive electrode adapter piece. The multiple stacked positive electrode tabs are soldered to one end of the positive electrode adapter piece, and the other end of the positive electrode adapter piece is soldered to the positive electrode post, so that the positive electrode tabs and the positive electrode post form an electrical connection.

[0114] The negative electrode generally includes a negative current collector and a negative active material layer. The negative active material layer is directly or indirectly coated on the negative current collector. The negative current collector without the negative active material layer protrudes from the negative current collector with the negative active material layer. The negative current collector without the negative active material layer serves as a negative electrode tab. Multiple negative electrode tabs are stacked together and form an electrical connection with the negative electrode post. For example, the stacked negative electrode tabs can be directly welded to the negative electrode post to form an electrical connection; alternatively, the battery cell assembly may also include a negative electrode adapter piece. The stacked negative electrode tabs are welded to one end of the negative electrode adapter piece, and the other end of the negative electrode adapter piece is welded to the negative electrode post, so that the negative electrode tabs and the negative electrode post form an electrical connection. The material of the separator is not limited; for example, it can be polypropylene or polyethylene.

[0115] Meanwhile, individual battery cells primarily function by the movement of metal ions between the positive and negative electrode plates. Taking lithium-ion batteries as an example, the positive electrode current collector can be made of aluminum, and the positive electrode active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode current collector can be made of copper, and the negative electrode active material layer can be made of carbon or silicon, etc. During charging and discharging, Li+ ions repeatedly insert and extract between the two electrodes: during charging, Li+ ions extract from the positive electrode, pass through the electrolyte, and insert into the negative electrode, leaving the negative electrode in a lithium-rich state; the reverse occurs during discharging.

[0116] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0117] In the field of battery technology, the design and manufacturing process of individual battery cells play a crucial role in the performance of battery devices. Currently, the tabs and adapter structures of some individual battery cells occupy a large amount of space, and their energy density needs to be improved.

[0118] Based on the above considerations, in order to improve the energy density of a single battery cell, this application designs a battery cell in which the tabs of the battery cell are welded together to form a tab portion. The first surface of the tab portion facing the electrode post body is flush with the second surface of the adapter piece facing the electrode post body. In this way, the adapter piece is not arranged on the side of the tab portion facing the electrode post body, that is, the adapter piece does not need to occupy the space on the side of the tab portion facing the electrode post body. As a result, the space occupied by the adapter piece in the housing along the mounting hole axis can be reduced, allowing the tab to have more bending space in the mounting hole axis, which facilitates the bending of the tab and reduces the probability of defects caused by bending. It can also provide more arrangement space for the active material coating part of the electrode assembly in the mounting hole axis, thereby improving the energy density of the battery cell.

[0119] This application provides an electrical device that uses the battery cell disclosed herein as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0120] For ease of explanation, the following embodiments use a vehicle as an example to describe in detail the structure of the electrical device 1, battery device 1000, and battery cell 100 of this application.

[0121] Please refer to Figure 1, which is a schematic diagram of the structure of an electrical device 1 as a vehicle according to some embodiments of this application. The vehicle can be a gasoline vehicle, a natural gas vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. The vehicle is equipped with a battery device 1000, which can be located at the bottom, front, or rear of the vehicle. The battery device 1000 can be used to supply power to the vehicle; for example, the battery device 1000 can serve as the vehicle's operating power source. The vehicle may also include a controller 2000 and a motor 3000. The controller 2000 is used to control the battery device 1000 to supply power to the motor 3000, for example, for the vehicle's starting, navigation, and driving power needs. In some embodiments of this application, the battery device 1000 can not only serve as the vehicle's operating power source but also as the vehicle's driving power source, replacing or partially replacing gasoline or natural gas to provide driving power to the vehicle.

[0122] Please refer to Figure 2, which is an exploded view of the structure of a battery device 1000 provided in some embodiments of this application. The battery device 1000 includes a housing 400 and a plurality of battery cells 100. The housing 400 provides a receiving space for the battery cells 100, which are housed within the housing 400. The housing 400 can adopt various structures. In some embodiments, the housing 400 may include a first housing 410 and a second housing 420, which overlap each other, and the first housing 410 and the second housing 420 together define a receiving space for accommodating the battery cells 100. The second box 420 can be a hollow structure with one open end, and the first box 410 can be a plate-like structure. The first box 410 covers the open side of the second box 420 so that the first box 410 and the second box 420 together define the accommodating space. Alternatively, the first box 410 and the second box 420 can both be hollow structures with one open side, and the open side of the first box 410 covers the open side of the second box 420. Of course, the box 400 formed by the first box 410 and the second box 420 can be of various shapes, such as a cylinder, a cuboid, etc.

[0123] Please refer to Figures 3 and 4. Figure 3 is a schematic diagram of the structure of a battery cell 100 provided in some embodiments of this application; Figure 4 is a partial structural cross-sectional view of a battery cell 100 according to some embodiments of this application. The battery cell 100 refers to the smallest unit constituting the battery device 1000. As shown in Figures 3 and 4, the battery cell 100 includes a housing 10, a terminal post component 20, an electrode assembly 30, and other functional components. The housing 10 includes a cover and a body 12.

[0124] A cover is a component that fits over the opening of the housing 12 to isolate the internal environment of the battery cell 100 from the external environment. The shape of the cover can be adapted to the shape of the housing 12 to fit it. Optionally, the cover can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the cover is less prone to deformation under pressure and impact, allowing the battery cell 100 to have higher structural strength and improved reliability. Functional components such as electrode post 20 can be provided on the cover. The electrode post 20 can be used to electrically connect with electrode components for outputting or inputting electrical energy into the battery cell 100. In some embodiments, the cover can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold. The material of the cover can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating element may be provided on the inner side of the cover. The insulating element can be used to isolate the electrical connection components inside the housing 12 from the cover to reduce the risk of short circuits. For example, the insulating element may be made of plastic, rubber, etc.

[0125] The housing 12 is a component used to cooperate with the cover to form the internal environment of the battery cell 100, wherein the formed internal environment can accommodate electrode components, electrolyte, and other components. The housing 12 and the cover can be independent components. An opening can be provided on the housing 12, and the cover can be used to close the opening to form the internal environment of the battery cell 100. Alternatively, the cover and housing 12 can be integrated. Specifically, the cover and housing 12 can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 12, the cover is then used to close the housing 12. The housing 12 can have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 12 can be determined according to the specific shape and size of the electrode components. The material of the housing 12 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment does not impose any special limitations on this.

[0126] Electrode assembly 30 is a component in the battery cell 100 where electrochemical reactions occur. The casing 12 may contain one or more electrode assemblies 30. During the charging and discharging process of the battery cell 100, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs 33 connect to the terminal components 20 to form a current circuit.

[0127] The battery cell 100 according to an embodiment of the first aspect of this application is described below with reference to Figures 4-20.

[0128] This application provides a battery cell 100. Referring to Figure 4 and Figure 5, Figure 4 is a partial structural cross-sectional view of the battery cell 100 according to Embodiment 1 of this application; Figure 5 is a structural schematic diagram of the electrode assembly 30 and the adapter piece 34 shown in Figure 4.

[0129] The battery cell 100 of this application embodiment includes a housing 10, a terminal post 20, an electrode assembly 30, and an adapter plate 34. The housing 10 has a receiving cavity 101 and includes a mounting wall 11 with a mounting hole 111. The terminal post 20 is mounted on the mounting wall 11 and includes a terminal post body 21, which is located at the mounting hole 111. The electrode assembly 30 is located in the receiving cavity 101 and includes an active material coating portion 31 and a tab 33 connected to the active material coating portion 31. The tab 33 is welded together to form a tab portion 331. The end face of the tab portion 331 facing the terminal post 20 is a first surface 3311. The adapter plate 34 is connected between the tab portion 331 and the terminal post body 21. The side surface of the adapter plate 34 that is welded to the terminal post body 21 is a second surface 3401. In the radial direction of the mounting hole 111, the first surface 3311 and the second surface 3401 are flush.

[0130] The mounting wall 11 is a part of the shell wall of the housing 10, which can serve as the mounting carrier for the pole component 20. The mounting wall 11 can be a part of the shell wall of the body 12 of the housing 10, or it can be the shell cover of the housing 10, or it can include a part of the shell wall of the body 12 and the shell cover.

[0131] "The terminal component 20 is mounted on the mounting wall 11" means that the terminal component 20 and the mounting wall 11 have an assembly connection relationship, such as welding or riveting. Thus, the housing 10 and the terminal component 20 are separate components, which are assembled and connected. This allows the housing 10 and the terminal component 20 to be processed separately, which facilitates the processing of both and the manufacturing of the battery cell 100.

[0132] The electrode assembly 30 is housed in the receiving cavity 101. The electrode assembly 30 includes an active material coating portion 31 and tabs 33. The portion of the current collector in the electrode assembly 30 coated with an active material layer constitutes the active material coating portion 31, and the portion without an active material layer constitutes the tabs 33. The tabs 33 include multiple layers of tab 33 sheets. The adapter piece 34 and the tabs 33 together constitute a conductive portion 32 connecting the active material coating portion 31 and the terminal body 21. The terminal body 21 is used to output or input electrical energy from the battery cell 100 through the conductive portion 32.

[0133] For example, when the electrode post 20 is the negative electrode, the electrode post body 21 can be a copper-aluminum composite component, wherein the copper-aluminum composite component can include an aluminum part and a copper part. The aluminum part is located on the side of the copper part away from the active material coating part 31, and can easily form a reliable connection with the aluminum busbar component. The copper part can easily connect with the copper foil tab 33 of the negative electrode. When the electrode post 20 is the positive electrode, the electrode post body 21 can be an aluminum component. The aluminum component can easily form a reliable connection with the aluminum busbar component, and the aluminum component can also easily connect with the aluminum foil tab 33 of the positive electrode.

[0134] As shown in Figures 3 and 4, the height direction of the active material coating part 31 is the first direction F1, the thickness direction of the active material coating part 31 is the second direction F2, the width direction of the active material coating part 31 is the third direction F1, and the conductive part 32 can be connected to one or both ends of the active material coating part 31 along the height direction.

[0135] In some examples, the tab 33 includes multiple tab pieces 33, one end of which is connected to the active material coating portion 31, and the other ends are folded together and welded together. The welded portion of the multiple tab pieces 33 forms the tab portion 331 of the tab 33. In some examples, the multiple tab pieces 33 can be connected by ultrasonic welding.

[0136] In some examples, the tab 331 extends radially along the mounting hole 111, and its two side surfaces in the thickness direction face the mounting hole 111 and the active material coating portion 31, respectively, wherein the surface of the tab 331 facing the mounting hole 111 is the first surface 3311. In some examples, the thickness direction of the tab 331 is parallel to the axial direction along the mounting hole 111 (the first direction F1 shown in FIG. 4), and the first surface 3311 is a plane perpendicular to the axis of the mounting hole 111.

[0137] In some examples, the adapter piece 34 has two side surfaces arranged opposite each other in the axial direction of the mounting hole 111, and the side surface of the adapter piece 34 facing the pole body 21 is a second surface 3401, which is welded to the pole body 21. In some examples, the adapter piece 34 and the pole body 21 can be connected by laser welding, resistance welding, pressure welding, or brazing.

[0138] In this embodiment, the first surface 3311 and the second surface 3401 are flush in the radial direction of the mounting hole 111. Here, "the first surface 3311 and the second surface 3401 are flush" can mean that they are on the same plane, or that they are substantially flush. It should be noted that during the assembly of the tab 331 and the adapter piece 34, due to limitations in processes and equipment, there may be assembly errors between the first surface 3311 and the second surface 3401. Therefore, in this embodiment, when the distance between the first surface 3311 and the second surface 3401 in the axial direction of the mounting hole 111 is less than a preset distance, it also indicates that the first surface 3311 and the second surface 3401 are flush in the radial direction of the mounting hole 111. Specifically, when the distance between the first surface 3311 and the second surface 3401 offset in the axial direction of the mounting hole 111 is less than or equal to 10% of the thickness of the tab 331, it indicates that the first surface 3311 and the second surface 3401 are flush.

[0139] In the above technical solution, since the first surface 3311 of the tab 331 is flush with the second surface 3401 of the adapter 34, it means that the adapter 34 will not be arranged on the side of the tab 331 facing the electrode body 21. In this way, the adapter 34 does not need to occupy the space of the tab 331 facing the electrode body 21. As a result, the space occupied by the adapter 34 in the housing 10 along the axial direction of the mounting hole 111 can be reduced, so that the tab 33 has more bending space in the axial direction of the mounting hole 111, which facilitates the bending of the tab 33 and reduces the probability of defects caused by bending of the tab 33. It can also provide more arrangement space for the active material coating part 31 of the electrode assembly 30 in the axial direction of the mounting hole 111, thereby improving the energy density of the battery cell 100.

[0140] Referring to FIG5, in some embodiments of this application, the tab 331 and the adapter 34 are arranged in sequence in the radial direction of the mounting hole 111, and the tab 331 and the adapter 34 are connected in the axial direction of the mounting hole 111.

[0141] For example, in Figure 5, the second direction F2 is the left-right direction. The tab 331 and the adapter 34 can be arranged in the left-right direction. Specifically, the adapter 34 can be arranged on the right side of the tab 331, and the left end of the adapter 34 is connected to the right end of the tab 331. This can further reduce the space occupied by the adapter 34 in the axial direction of the mounting hole 111, reduce the bending defects of the tab 33, and improve the energy density of the battery cell 100.

[0142] In some examples, the tab 331 and the adapter 34 can be radially mated together in the mounting hole 111, thereby simplifying the structure of the tab 331 and the mounting plate. For example, the surface of the tab 331 facing the adapter 34 is a first end face extending axially along the mounting hole 111, and the surface of the adapter 34 facing the tab 331 is a second end face extending axially along the mounting hole 111, with the first end face and the second end face fitting together.

[0143] In some examples, the tab 331 and the adapter piece 34 can also be joined together radially in the mounting hole 111. This increases the contact area between the tab 331 and the adapter piece 34, improving the connection strength and reliability between them. For example, as shown in Figure 5, the tab 331 and the adapter piece 34 are arranged in the second direction F2, and their opposite ends in the second direction F2 are stacked in the first direction F1, so that the tab 331 and the adapter piece 34 are joined together.

[0144] In the above technical solution, by arranging the tab 331 and the adapter 34 radially in the mounting hole 111 and connecting them axially in the mounting hole 111, it is possible not only to further reduce the space occupied by the adapter 34 in the axial direction of the mounting hole 111, reduce the bending defects of the tab 33, and improve the energy density of the battery cell 100, but also to increase the contact area between the tab 331 and the adapter 34, improve the connection strength and reliability between the tab 331 and the adapter 34, and improve the conductivity.

[0145] Referring to Figures 4 and 5, in some embodiments of this application, at least a portion of the end face of the tab 331 facing the adapter 34 in the radial direction of the mounting hole 111 is formed as a first inclined surface 3312. The first inclined surface 3312 is inclined relative to the thickness direction of the tab 331. At least a portion of the surface of the adapter 34 facing the tab 331 is formed as a second inclined surface 3402. The first inclined surface 3312 and the second inclined surface 3402 are fitted and connected together.

[0146] In other words, the end face of the tab 331 facing the adapter plate 34 can be partially or entirely formed as the first inclined surface 3312. In some examples, the thickness direction of the tab 331 is along the first direction F1 shown in FIG4, and the first inclined surface 3312 is inclined relative to the first direction F1. The first inclined surface 3312 can be an inclined surface that is inclined relative to the first direction F1, or it can be an arc surface that protrudes towards the adapter plate 34 or is recessed away from the adapter plate 34 in the second direction F2.

[0147] The end face of the adapter piece 34 facing the tab 331 can be partially or entirely formed as the second bevel 3402. The shapes of the first bevel 3312 and the second bevel 3402 are adapted to allow them to fit tightly together. In some examples, the adapter piece 34 and the tab 331 can be ultrasonically welded together in the area where the first bevel 3312 and the second bevel 3402 fit together.

[0148] In this embodiment, the tab 331 and the adapter 34 are respectively formed with a first inclined surface 3312 and a second inclined surface 3402, and are connected by the first inclined surface 3312 and the second inclined surface 3402. This can increase the connection length between the tab 331 and the adapter 34, increase the connection contact area between the tab 331 and the adapter 34, and improve the connection reliability between the tab 331 and the adapter 34.

[0149] Meanwhile, since the end faces of the adapter piece 34 connected to the tab 331 respectively form a first inclined surface 3312 and a second inclined surface 3402, the length of the adapter piece 34 after the connection between the tab 331 and the adapter piece 34 remains unchanged, the second inclined surface 3402 can be formed by extending the adapter piece 34, thereby increasing the length of the adapter piece 34 in the radial direction of the mounting hole 111; and the first inclined surface 3312 can be formed on the tab 331 by shortening the tab 33, thereby reducing the length of the tab 331 in the radial direction of the mounting hole 111 and reducing the length of the tab 33.

[0150] In this way, on the one hand, the amount of material used for the tab 33 can be reduced, thus reducing the cost of the electrode assembly 30. On the other hand, the shorter tab 33 can reduce the probability of the tab 33 wrinkling during the winding of the electrode assembly 30, significantly reducing the risk of the tab 33 folding defects. In addition, the shorter tab 33 can reduce the space occupied by the tab 33 in the housing 10 of the battery cell 100, providing more space for the electrode assembly 30, thereby further improving the energy density of the battery cell 100.

[0151] Furthermore, since the greater the thickness of the electrode assembly 30, the larger the space occupied by the tab 33 after it is folded up (folded portion 332) in the height direction of the electrode assembly 30 (for example, the first direction F1 shown in FIG5), and the larger the space required for the tab 33 to be bent and accommodated, the shorter the tab 331 is, the larger the space that can accommodate the folded portion 332 of the tab 33 of the electrode assembly 30 can be, while occupying the same height space in the housing 10 along the axial direction of the mounting hole 111. This can increase the thickness of the electrode assembly 30 and improve the adaptability to the thickness of the electrode assembly 30.

[0152] In the above technical solution, by forming a first inclined surface 3312 on the end face of the tab 331 and a second inclined surface 3402 on the end face of the adapter piece 34, and by fitting the first inclined surface 3312 and the second inclined surface 3402 together, the connection length between the tab 331 and the adapter piece 34 can be increased, the connection reliability between the tab 331 and the adapter piece 34 can be improved, the conductivity can be enhanced, the probability of the tab 33 folding defect during the winding of the electrode assembly 30 can be reduced, the energy density of the battery cell 100 can be increased, and the adaptability to the thickness of the electrode assembly 30 can be improved.

[0153] Referring to Figure 5 and in conjunction with Figures 6-8, Figure 6 is a structural schematic diagram of the tab 331 and the adapter 34 in Figure 5; Figure 7 is a partial structural cross-sectional view of the battery cell 100 according to Embodiment 2 of this application; Figure 8 is a structural schematic diagram of the electrode assembly 30 and the adapter 34 shown in Figure 7; In some embodiments of this application, the first inclined surface 3312 and the second inclined surface 3402 are planes.

[0154] In some examples, in the direction from the tab 331 toward the adapter 34, both the first inclined surface 3312 and the second inclined surface 3402 are formed as inclined surfaces extending obliquely toward the electrode body 21, or both the first inclined surface 3312 and the second inclined surface 3402 are formed as inclined surfaces extending obliquely toward the active material coating portion 31. The first inclined surface 3312 and the second inclined surface 3402 are parallel to each other and fit together.

[0155] In some examples, the first inclined surface 3312 and the second inclined surface 3402 are completely in contact. That is, when the first inclined surface 3312 and the second inclined surface 3402 are in contact, one of the first inclined surface 3312 and the second inclined surface 3402 completely covers the other. As a result, the connection length and contact area between the first inclined surface 3312 and the second inclined surface 3402 can be further increased, improving the connection reliability between the tab 331 and the adapter piece 34.

[0156] In the above technical solution, the first inclined surface 3312 and the second inclined surface 3402 are planes, which can simplify the structure of the electrode tab 331 and the adapter piece 34, facilitate the forming of the first inclined surface 3312 and the second inclined surface 3402, reduce the processing difficulty, and improve production efficiency.

[0157] Referring to Figures 5 and 6, in some embodiments of this application, the angle α between the first inclined surface 3312 and the second inclined surface 3402 and one side surface of the tab portion 331 in the thickness direction is greater than or equal to 20° and less than or equal to 45°.

[0158] That is, the angle α between the first inclined plane 3312 and the first surface 3311 is greater than or equal to 20° and less than or equal to 45°, and the angle α between the second inclined plane 3402 and the first surface 3311 is also greater than or equal to 20° and less than or equal to 45°.

[0159] As shown in Figure 6, the angle between either the first inclined plane 3312 or the second inclined plane 3402 and the first surface 3311 is the first included angle, which satisfies the condition: 20° ≤ a ≤ 45°. For example, the first included angle a can be 20°, 22°, 25°, 28°, 30°, 32°, 35°, 38°, 40°, 42°, or 45°.

[0160] It should be noted that, due to the relatively small thickness of the tab 331 and the adapter piece 34, when the angle between the first inclined surface 3312 and the second inclined surface 3402 and the first surface 3311 is too small, for example, less than 20°, the processing is difficult and not conducive to the forming of the first inclined surface 3312 and the second inclined surface 3402. When the angle between the first inclined surface 3312 and the second inclined surface 3402 and the first surface 3311 is too large, the length of the first inclined surface 3312 and the second inclined surface 3402 will be too short, affecting the reliability of the connection between the first inclined surface 3312 and the second inclined surface 3402. Furthermore, when the tab 331 and the adapter piece 34 are ultrasonically welded, poor ultrasonic welding quality is easily caused.

[0161] In the above technical solution, by setting the angle between either the first inclined surface 3312 and the second inclined surface 3402 and the first surface 3311 to be greater than or equal to 20° and less than or equal to 45°, it is not only convenient to form the first inclined surface 3312 and the second inclined surface 3402, but also to further increase the length of the first inclined surface 3312 and the second inclined surface 3402, increase the connection length between the adapter piece 34 and the electrode tab 331, improve the ultrasonic welding quality between the first inclined surface 3312 and the second inclined surface 3402, and improve the connection reliability and conductivity of the adapter piece 34 and the electrode tab 331.

[0162] Referring to FIG6, in some embodiments of this application, the ratio of the length of the first inclined surface 3312 along the inclined direction of the first inclined surface 3312 to the thickness of the tab portion 331 is greater than or equal to 2 and less than or equal to 3.

[0163] For example, as shown in Figure 6, the length of the first inclined surface 3312 along the inclination direction of the first inclined surface 3312 is the length of the inclined surface, and the thickness of the tab 331 is the thickness of the tab 33. The length of the inclined surface L and the thickness d of the tab 33 satisfy: 2≤L / d≤3.

[0164] For example, the ratio of the inclined plane length L to the thickness d of the tab 33 can be 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9 or 3, etc.

[0165] In some examples, the ratio of the length L of the second inclined surface 3402 along its inclined direction to the thickness d of the tab 331 is greater than or equal to 2 and less than or equal to 3. For example, the ratio of the length L of the second inclined surface 3402 along its inclined direction to the thickness d of the tab 331 can be 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3, etc. This allows for increasing the length of the second inclined surface 3402, shortening the length of the tab 331, and improving the energy density of the battery cell 100.

[0166] In the above technical solution, the ratio of the length of the first inclined surface 3312 to the thickness of the tab 33 of the tab portion 331 is greater than or equal to 2 and less than or equal to 3, which facilitates the forming of the first inclined surface 3312, increases the length of the first inclined surface 3312, increases the connection length between the adapter piece 34 and the tab portion 331, and improves the connection reliability and conductivity between the adapter piece 34 and the tab portion 331.

[0167] Referring to FIG5, in some embodiments of this application, the length of the first inclined surface 3312 along the inclined direction of the first inclined surface 3312 is greater than or equal to 2 mm and less than or equal to 3 mm.

[0168] For example, the length L of the first inclined plane 3312 can be 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3mm.

[0169] In some examples, the length of the second inclined surface 3402 along its inclined direction is greater than or equal to 2 mm and less than or equal to 3 mm. For example, the length of the second inclined surface 3402 along its inclined direction can be 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, or 3 mm. This increases the length of the second inclined surface 3402, shortens the length of the tab 331, and improves the energy density of the battery cell 100.

[0170] In the above technical solution, the length of the first inclined surface 3312 is greater than or equal to 2mm and less than or equal to 3mm, which can increase the length of the first inclined surface 3312, increase the connection length between the adapter piece 34 and the electrode tab 331, and improve the connection reliability between the adapter piece 34 and the electrode tab 331.

[0171] Referring to FIG5, in some embodiments of this application, the total area of ​​the first inclined surface 3312 on the end face of the tab 331 facing the adapter piece 34 is greater than or equal to 40 mm2 and less than or equal to 60 mm2.

[0172] The total area of ​​the first inclined surface 3312 refers to the total area of ​​the first inclined surface 3312 when the tab 331 includes only one first inclined surface 3312, and the total area of ​​the first inclined surface 3312 when the tab 331 includes multiple first inclined surfaces 3312.

[0173] For example, the total area of ​​the first inclined surface 3312 on the tab 331 can be 40mm2, 42mm2, 45mm2, 48mm2, 50mm2, 52mm2, 55mm2, 58mm2 or 60mm2.

[0174] In some examples, the total area of ​​the second inclined surface 3402 on the end face of the adapter 34 facing the tab 331 is greater than or equal to 40 mm² and less than or equal to 60 mm². For example, the total area of ​​the second inclined surface 3402 on the adapter 34 can be 40 mm², 42 mm², 45 mm², 48 mm², 50 mm², 52 mm², 55 mm², 58 mm², or 60 mm². This increases the area of ​​the second inclined surface 3402, increases the contact area between the adapter 34 and the tab 331, and improves the connection reliability between the adapter 34 and the tab 331.

[0175] In the above technical solution, the total area of ​​the first inclined surface 3312 on the end face of the tab 331 facing the adapter plate 34 is greater than or equal to 40 mm2 and less than or equal to 60 mm2, which can make the tab 331 have sufficient contact and contact area with the adapter plate 34, thereby improving the connection reliability between the tab 331 and the adapter plate 34.

[0176] Referring to FIG6, in some embodiments of this application, the distance between one end of the tab 331 away from the adapter plate 34 and the one end of the first inclined surface 3312 away from the adapter plate 34 is a first distance H, which is greater than or equal to 2 mm and less than or equal to 3 mm.

[0177] As shown in Figure 6, the first spacing H satisfies: 2mm ≤ H ≤ 3mm. For example, the first spacing H can be 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm or 3mm.

[0178] It should be noted that when the distance H between the end of the tab 331 away from the adapter piece 34 and the end of the first inclined surface 3312 away from the adapter piece 34 is too short, for example, less than 2mm, multiple tabs 33 cannot be pressed in, thus making it impossible to weld multiple tabs 33 together. When the distance H between the end of the tab 331 away from the adapter piece 34 and the end of the first inclined surface 3312 away from the adapter piece 34 is too long, for example, greater than 3mm, it will increase the total length of the tab 331, which may easily cause the tab 33 to fold during the winding of the electrode assembly 30.

[0179] In the above technical solution, the distance between the end of the tab 331 facing away from the adapter piece 34 and the end of the first inclined surface 3312 facing away from the adapter piece 34 is greater than or equal to 2 mm and less than or equal to 3 mm. This allows for sufficient press-fit length during welding of multiple tabs 33, ensuring effective welding of the multiple tabs 33, while further reducing the probability of folding defects in the tabs 33 and further improving the adaptability to the thickness of the electrode assembly 30.

[0180] Referring to Figures 6-8, in some embodiments of this application, the distance between the end edge of the tab 331 away from the adapter plate 34 and the end edge of the adapter plate 34 away from the tab 331 is a first dimension L0, which is less than or equal to 12mm.

[0181] In other words, in the radial direction of the mounting hole 111, the distance between the end edges of the opposite end of the tab 331 and the adapter piece 34 is less than or equal to 12 mm. For example, as shown in Figure 6, the first dimension L0 can be 12 mm, 11 mm, 10 mm, 9 mm, 8 mm, 7 mm, 6 mm, 5 mm, or 4 mm, etc.

[0182] It should be noted that the tab 331 and the adapter 34 together constitute the horizontal segment of the conductive part 32. The radial dimension of the horizontal segment in the mounting hole 111 is a first dimension L0, and the first dimension L0 is less than or equal to 12 mm. The first dimension of the horizontal segment is set according to the width of the electrode body 21. In some examples, the first dimension of the horizontal segment is greater than or equal to the width of the electrode body 21; for example, the first dimension of the horizontal segment is greater than or equal to the width of the electrode body 21 and less than or equal to 1.2 times the width of the electrode body 21. Therefore, while achieving a reliable and effective connection between the horizontal segment and the electrode body 21, the size of the horizontal segment can be reduced, saving material and space occupied by the horizontal segment.

[0183] In the above technical solution, the distance between the end edge of the tab 331 away from the adapter plate 34 and the end edge of the adapter plate 34 away from the tab 331 is less than or equal to 12mm. This allows the length of the horizontal section of the conductive part 32 to be adapted to the width of the pole post, which facilitates the connection between the pole post and the horizontal section, improves the connection reliability, reduces the amount of material used, and reduces the space occupied in the housing 10.

[0184] Referring to FIG6, in some embodiments of this application, the first dimension L0 is greater than or equal to 8 mm and less than or equal to 10 mm.

[0185] For example, the first dimension can be 8mm, 8.2mm, 8.4mm, 8.6mm, 8.8mm, 9mm, 9.2mm, 9.4mm, 9.6mm, 9.8mm or 10mm.

[0186] In some examples, the tab 331 and the adapter 34 together form the horizontal section of the conductive part 32, which is connected to the electrode body 21 by laser welding. When the horizontal section is connected to the electrode body 21 by laser welding, the length of the horizontal section needs to be greater than or equal to 8 mm to meet the requirements of the laser welding process.

[0187] In some examples, the tab 331 is connected to the adapter 34 by ultrasonic welding, and the adapter 34 is connected to the pole body 21 by laser welding. The ultrasonic welding positions and the laser welding positions are arranged alternately to improve the welding quality.

[0188] In the above technical solution, the first dimension L0 is greater than or equal to 8mm and less than or equal to 10mm, which can make the horizontal section have sufficient length to realize the welding connection with the pole body 21, and reduce the probability that the welding position of the pole body 21 and the adapter piece 34 coincides with the welding position of the adapter piece 34 and the pole ear 331, thereby improving the welding quality.

[0189] Referring to Figure 6, and in conjunction with Figures 9 and 10, Figure 9 is a structural cross-sectional view of the electrode assembly 30 and the adapter piece 34 of the battery cell 100 according to Embodiment 3 of this application; Figure 10 is a structural cross-sectional view of the electrode assembly 30 and the adapter piece 34 of the battery cell 100 according to Embodiment 4 of this application; in some embodiments of this application, the first dimension is less than or equal to 6 mm.

[0190] For example, the first dimension L0 can be 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, or 6mm. In some examples, the electrode body 21 of the battery cell 100 is a narrow electrode. When the first dimension is less than or equal to 6mm, the length of the horizontal segment of the conductive portion 32 can be adapted to the narrow electrode of the battery cell 100.

[0191] In the above technical solution, the first dimension is less than or equal to 6mm, which can make the length of the horizontal section of the conductive part 32 match the width of the narrow pole. While achieving effective connection between the horizontal section and the pole body 21, the length of the horizontal section is reduced, the space occupied by the horizontal section in the housing 10 is reduced, and the energy density of the battery cell 100 is increased.

[0192] Referring to Figures 9 and 10, in some embodiments of this application, the second inclined surface 3402 extends from one end of the adapter piece 34 toward the tab 331 to the other end away from the tab 331.

[0193] In other words, in the projection plane perpendicular to the axial direction of the mounting hole 111, the projected length of the second inclined surface 3402 is equal to the projected length of the adapter piece 34. In other words, in the radial direction of the mounting hole 111, the two end edges of the second inclined surface 3402 are flush with the two end edges of the adapter piece 34. Thus, when the length of the connecting piece is constant, the inclined surface length of the second inclined surface 3402 can be maximized, increasing the connection length between the adapter piece 34 and the electrode lug 331, and improving the connection reliability between the adapter piece 34 and the electrode lug 331.

[0194] In the above technical solution, by extending the second inclined surface 3402 from one end of the adapter piece 34 toward the electrode tab 331 to the other end away from the electrode tab 331, the second inclined surface 3402 with the longest inclined surface size can be formed on the adapter piece 34 of a limited length, thereby increasing the connection length between the adapter piece 34 and the electrode tab 331 and improving the connection reliability between the adapter piece 34 and the electrode tab 331.

[0195] Referring to Figures 4-10, in some embodiments of this application, the number of first inclined surfaces 3312 on the tab 331 is one, and the two ends of the first inclined surface 3312 in the radial direction of the mounting hole 111 extend to the two side surfaces of the tab 331 in the thickness direction.

[0196] In other words, the end face of the tab 331 facing the adapter piece 34 is formed as a first inclined surface 3312, and the two sides of the first inclined surface 3312 in the axial direction of the mounting hole 111 intersect with the two sides of the tab 331 in the thickness direction.

[0197] In the above technical solution, the end face of the tab 331 facing the adapter piece 34 is formed into a first inclined surface 3312, which can simplify the end face structure of the tab 331, facilitate molding, and also facilitate the bonding and welding of the first inclined surface 3312 with the adapter piece 34, reducing the welding difficulty.

[0198] Referring to Figures 11-14, Figure 11 is a partial structural cross-sectional view of the battery cell 100 according to Embodiment 5 of this application; Figure 12 is a structural schematic diagram of the electrode assembly 30 and the adapter piece 34 shown in Figure 11; Figure 13 is a partial structural cross-sectional view of the battery cell 100 according to Embodiment 6 of this application; Figure 14 is a structural schematic diagram of the electrode assembly 30 and the adapter piece 34 shown in Figure 13; In some embodiments of this application, the end face of the tab 331 facing the adapter piece 34 is formed with a plurality of first inclined surfaces 3312, the plurality of first inclined surfaces 3312 are arranged along the thickness direction of the tab 331, and there are a plurality of second inclined surfaces 3402, the plurality of second inclined surfaces 3402 and the plurality of first inclined surfaces 3312 are fitted one-to-one.

[0199] For example, the number of first inclined surfaces 3312 can be two, three, four, five, or more, etc. The number of second inclined surfaces 3402 can be two, three, four, five, or more, etc. This can further increase the connection area between the tab 331 and the adapter piece 34, and improve the connection strength.

[0200] In some examples, the inclination directions of any two first inclined surfaces 3312 can be the same or different, and the inclination directions of any two second inclined surfaces 3402 can be the same or different. Therefore, the inclination direction of each first inclined surface 3312 and each second inclined surface 3402 can be set according to the connection requirements between the adapter piece 34 and the tab 331.

[0201] In some examples, the angles between any two first inclined planes 3312 and the first surface 3311 can be the same or different, and the angles between any two second inclined planes 3402 and the first surface 3311 can be the same or different. Therefore, the tilt angles of each first inclined plane 3312 and second inclined plane 3402 can be set according to connection requirements.

[0202] In some examples, any two adjacent first inclined surfaces 3312 can be directly connected in the thickness direction of the tab 331, and any two adjacent second inclined surfaces 3402 can also be directly connected. Alternatively, any two adjacent first inclined surfaces 3312 can be indirectly connected in the thickness direction of the tab 331 through a first connecting surface extending along the thickness direction of the tab 331, and any two adjacent second inclined surfaces 3402 can be indirectly connected through a second connecting surface extending along the thickness direction of the tab 331. The first connecting surface and the second connecting surface correspond one-to-one and fit together.

[0203] In some examples, the first inclined surfaces 3312 located on both sides of the tab 331 in the thickness direction can be directly connected to the adjacent surface of the tab 331 in the thickness direction, or indirectly connected to the adjacent surface of the tab 331 in the thickness direction through a first connecting surface extending along the thickness direction of the tab 331. The second inclined surfaces 3402 located on both sides of the adapter 34 in the thickness direction can be directly connected to the adjacent surface of the adapter 34 in the thickness direction, or indirectly connected to the adjacent surface of the adapter 34 in the thickness direction through a second connecting surface extending along the thickness direction of the adapter 34.

[0204] In the above technical solution, the end face of the tab 331 is formed with a plurality of first inclined surfaces 3312, and the end face of the adapter 34 is formed with a plurality of second inclined surfaces 3402 corresponding one-to-one with the plurality of first inclined surfaces 3312. This can increase the total inclined surface length of the plurality of first inclined surfaces 3312 and the total inclined surface length of the plurality of second inclined surfaces 3402, increase the connection length and connection area between the adapter 34 and the tab 331, and improve the connection reliability and conductivity of the adapter 34 and the tab 331.

[0205] Referring to Figures 12 and 14, in some embodiments of this application, a plurality of first inclined surfaces 3312 are sequentially connected in the thickness direction of the tab portion 331.

[0206] "Multiple first inclined surfaces 3312 are connected sequentially in the thickness direction of the tab portion 331" means that in the thickness direction of the tab portion 331, the adjacent ends of two adjacent first inclined surfaces 3312 are directly connected so that multiple first inclined surfaces 3312 are continuous and uninterrupted in the thickness direction of the tab portion 331.

[0207] In some examples, in the thickness direction of the tab 331 (e.g., the first direction F1 shown in FIG12), a plurality of first inclined surfaces 3312 are connected in sequence, and a plurality of second inclined surfaces 3402 correspond one-to-one with the plurality of first inclined surfaces 3312 and are connected in sequence.

[0208] In the above technical solution, multiple first inclined surfaces 3312 are connected in sequence, which can increase the total inclined surface length of multiple first inclined surfaces 3312 and the total inclined surface length of multiple second inclined surfaces 3402, increase the connection length and connection area between the adapter piece 34 and the electrode tab 331, and improve the connection reliability between the adapter piece 34 and the electrode tab 331.

[0209] Referring to Figures 12 and 14, in some embodiments of this application, in the thickness direction of the tab 331, the inclination directions of two adjacent first inclined surfaces 3312 are opposite, and the inclination directions of two adjacent second inclined surfaces 3402 are opposite.

[0210] "The two adjacent first inclined surfaces 3312 have opposite inclination directions" means that in the direction from one side surface to the other side surface in the thickness direction of the tab 331, the two adjacent first inclined surfaces 3312 extend inclined towards opposite sides in the radial direction of the mounting hole 111.

[0211] For example, as shown in Figure 12, the end face of the tab 331 facing the adapter 34 has two first inclined surfaces 3312. In the direction along the first direction F1 from the first surface 3311 toward the active material coating portion 31, the first inclined surface 3312 connected to the first surface 3311 extends obliquely away from the adapter 34, and the other first inclined surface 3312 extends obliquely toward the adapter 34. The end face of the adapter 34 facing the tab 33 has two second inclined surfaces 3402. In the direction from the second surface 3401 toward the active material coating portion 31, the second inclined surface 3402 connected to the second surface 3401 extends obliquely away from the adapter 34, and the other second inclined surface 3402 extends obliquely toward the adapter 34.

[0212] As shown in Figure 14, the end face of the tab 331 facing the adapter 34 has two first inclined surfaces 3312. In the direction along the first direction F1 from the first surface 3311 toward the active material coating portion 31, the first inclined surface 3312 connected to the first surface 3311 extends obliquely toward the adapter 34, and the other first inclined surface 3312 extends obliquely away from the adapter 34. The end face of the adapter 34 facing the tab 33 has two second inclined surfaces 3402. In the direction from the second surface 3401 toward the active material coating portion 31, the second inclined surface 3402 connected to the second surface 3401 extends obliquely toward the adapter 34, and the other second inclined surface 3402 extends obliquely away from the adapter 34.

[0213] In the above technical solution, by setting the inclination directions of two adjacent first inclined surfaces 3312 to be opposite, the total inclined surface length of multiple first inclined surfaces 3312 and the total inclined surface length of multiple second inclined surfaces 3402 can be further increased, thereby increasing the connection length and connection area between the adapter piece 34 and the electrode tab 331 and improving the connection reliability between the adapter piece 34 and the electrode tab 331.

[0214] Referring to Figures 12-14, in some embodiments of this application, the end face of the tab 331 facing the adapter piece 34 includes two first inclined surfaces 3312.

[0215] In the direction from the tab 331 toward the adapter piece 34, two first inclined surfaces 3312 extend toward each other or toward each other. In the axial direction of the mounting hole 111, adjacent ends of the two first inclined surfaces 3312 are directly connected. Alternatively, the end face of the tab 331 toward the adapter piece 34 may also include a connecting surface, which extends along the axial direction of the mounting hole 111. In the axial direction of the mounting hole 111, adjacent ends of the two first inclined surfaces 3312 are connected by the connecting surface.

[0216] "The two first inclined surfaces 3312 extend toward each other" means that in the direction from the tab 331 toward the adapter 34, the two first inclined surfaces 3312 extend toward each other, so that the distance between the two first inclined surfaces 3312 in the thickness direction of the tab 331 gradually decreases. At this time, in the axial direction of the mounting hole 111 from the active material coating portion 31 toward the pole body 21, the surface formed by the two first inclined surfaces 3312 first extends obliquely toward the adapter 34, and then extends obliquely away from the adapter 34.

[0217] "The two first inclined surfaces 3312 extend away from each other" means that in the direction from the tab 331 toward the adapter plate 34, the two first inclined surfaces 3312 extend away from each other, so that the distance between the two first inclined surfaces 3312 in the thickness direction of the tab 331 gradually increases. At this time, in the axial direction of the mounting hole 111 from the active material coating portion 31 toward the pole body 21, the surface formed by the two first inclined surfaces 3312 first extends obliquely away from the adapter plate 34, and then extends obliquely toward the adapter plate 34.

[0218] When the two first inclined surfaces 3312 extend toward each other in the direction toward the adapter piece 34, if the ends of the two first inclined surfaces 3312 toward the adapter piece 34 are directly connected, the two first inclined surfaces 3312 form a V-shape that bulges toward the adapter piece 34. If the ends of the two first inclined surfaces 3312 toward the adapter piece 34 are connected through a connecting surface, the two first inclined surfaces 3312 and the connecting surface together form a trapezoidal shape that bulges toward the adapter piece 34.

[0219] When the two first inclined surfaces 3312 extend in opposite directions toward the adapter piece 34, the adjacent ends of the two first inclined surfaces 3312 are the ends that are away from the adapter piece 34. If the ends of the two first inclined surfaces 3312 that are away from the adapter piece 34 are directly connected, then the two first inclined surfaces 3312 form a V-shaped groove that is recessed away from the adapter piece 34. If the ends of the two first inclined surfaces 3312 that are away from the adapter piece 34 are connected through a connecting surface, then the two first inclined surfaces 3312 and the connecting surface together form a trapezoidal groove that is recessed away from the adapter piece 34.

[0220] In the above technical solution, by making the tab 331 have two first inclined surfaces 3312 extending toward or away from the adapter plate 34, and the adjacent ends of the two first inclined surfaces 3312 are directly connected or connected through a connecting surface, the end face structure of the tab 331 and the adapter plate 34 can be simplified and the production difficulty reduced, while further increasing the connection length and connection area between the tab 331 and the adapter plate 34.

[0221] In the direction from the adapter plate 34 toward the tab portion 331, the two first inclined surfaces 3312 extend toward each other and connect.

[0222] Referring to Figures 12-14, in some embodiments of this application, the tab 33 further includes a gathering portion 332, which is connected between the tab portion 331 and the active material coating portion 31, and is formed by gathering one end of a plurality of tab pieces 33 connected to the active material coating portion 31.

[0223] In other words, the roots of multiple tabs 33 adjacent to the active material coating portion 31 are brought together to form a triangular converging portion 332. For ease of understanding, a cross-section is taken perpendicular to the length direction of the active material coating portion 31 (the third direction F1 as shown in Figure 3), and the cross-sectional shape of the converging portion 332 is triangular.

[0224] The triangle can be an isosceles triangle, meaning that the vertex of the triangle is aligned with the center of the pole body 21 in the width direction of the pole body 21; the vertex of the triangle can also be offset from the center of the pole body 21 in the width direction of the pole body 21 (thickness direction of the active material coating part 31).

[0225] In the above technical solution, multiple tabs 33 are brought together near the roots of the active material coating part 31 to form a gathering part 332, so that multiple tabs 33 can be stacked and formed into a whole that is not easy to loosen, thereby facilitating the connection between the tab part 331 and the adapter piece 34 and the pole body 21.

[0226] Referring to Figures 15 and 16, Figure 15 is a structural cross-sectional view of the electrode assembly 30 and the adapter piece 34 of the battery cell 100 according to Embodiment 7 of this application; Figure 16 is a structural schematic diagram of the battery cell 100 shown in Figure 15 when the tab 33 is straightened and welded to the adapter piece 34; in some embodiments of this application, the adapter piece 34 includes a first segment 341, a second segment 342 and a connecting segment 343. The first segment 341 is located on the side of the tab 331 away from the electrode post body 21 and is connected to the tab 331. The second segment 342 is arranged with the tab 331 in the extending direction of the tab 331. The second segment 342 is connected to the electrode post body 21. The surface of the second segment 342 facing the electrode post body 21 is formed as a second surface 3401. The connecting segment 343 connects the first segment 341 and the second segment 342.

[0227] "The second segment 342 and the tab 331 are arranged in the extending direction of the tab 331" means that the second segment 342 is arranged on one side of the tab 331 in the extending direction, so as to be arranged side by side or spaced apart from the tab 331 in the radial direction of the mounting hole 111.

[0228] The connecting segment 343 extends axially along the mounting hole 111. One end of the connecting segment 343 is connected to the end of the first segment 341 away from the retracting portion 332, and the other end of the connecting segment 343 is connected to the end of the second segment 342 facing the tab 331. The connecting segment 343 can extend parallel to the axial direction of the mounting hole 111, or it can be inclined relative to the axial direction of the mounting hole 111 to connect the first segment 341 and the second segment 342. This allows the first segment 341 and the second segment 342 to be offset axially from each other in the mounting hole 111, so that the second segment 342 can be flush with the tab 331, and the first segment 341 can overlap and connect with the tab 331.

[0229] In some examples, referring to FIG16, when the adapter piece 34 is welded to the tab 331, the first segment 341 is placed on one side of the thickness direction of the tab 331 so that the first segment 341 and the tab 331 are stacked. Then, the tab 331 and the first segment 341 are placed as a whole between the welding head 2B and the welding seat 2A of the welding device 2. The welding head 2B and the welding seat 2A are respectively arranged on both sides of the tab 331 and the first segment 341 in the thickness direction.

[0230] In the above technical solution, the adapter plate 34 includes a first section 341 and a second section 342 that are offset from each other in the axial direction of the mounting hole 111, and a connecting section 343 that connects the first section 341 and the second section 342. Under the premise of achieving the overlapping connection between the first section 341 and the electrode tab 331, it is convenient for the second section 342 to be flush with the electrode tab 331, reducing the space occupied, reducing the length of the electrode tab 33, and reducing the risk of the electrode tab 33 folding defects.

[0231] Referring to Figure 5, in some embodiments of this application, the adapter piece 34 includes multiple stacked and connected adapter foils to make the adapter piece 34 deformable. The material of the multiple adapter foils can be the same as the material of the tab 33, and the multiple adapter foils can be welded together at several key locations using methods such as ultrasonic welding to connect them together. In the above technical solution, since the thickness of the multiple adapter foils is relatively small, the multiple adapter foils are equivalent to multiple thin plates. Compared to a one-piece molded adapter piece 34, the adapter piece 34 formed by multiple adapter foils allows for easier forming of the second inclined surface 3402, simplifying processing.

[0232] Referring to FIG4, in some embodiments of this application, the tab 33 is welded and / or bonded to the adapter piece 34, and the adapter piece 34 is welded and / or bonded to the pole body 21.

[0233] In some examples, the tab 33 and the adapter 34 form a conductive part 32 that connects the electrode body 21 and the active material coating part 31. The conductive part 32 and the electrode body 21 can be connected by ultrasonic welding, ultrasonic pre-welding + laser welding, resistance welding, pressure welding, brazing or adhesive bonding.

[0234] In some examples, the tab 33 and the adapter 34 can be ultrasonically welded together or bonded together with conductive adhesive.

[0235] In the above technical solution, the tab 33, the adapter piece 34 and the pole body 21 are welded or bonded together, which can achieve an effective connection between the tab 33, the adapter piece 34 and the pole body 21, and ensure the conductivity between the tab 33, the adapter piece 34 and the pole body 21.

[0236] Referring to FIG4, in some embodiments of this application, the pole member 20 is covered with the mounting hole 111, and the edge of the pole member 20 is supported on the side of the mounting wall 11 that is away from or close to the receiving cavity 101.

[0237] For example, the terminal post 20 can be disposed on the side of the mounting hole 111 away from the receiving cavity 101 and cover the position of the mounting hole 111. The edge of the terminal post 20 is supported on the side of the mounting wall 11 away from the receiving cavity 101. This not only simplifies the structure of the terminal post 20, but also reduces the space occupied by the terminal post 20 in the receiving cavity 101, providing more space for the active material coating part 31 and improving the energy density of the battery cell 100.

[0238] For example, the pole piece 20 is placed over the mounting hole 111, and the edge of the pole piece 20 is supported on the side of the mounting wall 11 near the receiving cavity 101. This can improve the connection reliability and sealing performance between the pole piece 20 and the mounting wall 11.

[0239] In the above technical solution, the terminal component 20 is covered by the mounting hole 111, which can simplify the structure of the terminal component 20 and improve the energy density of the battery cell 100. The edge of the terminal component 20 is supported on the inner or outer side of the mounting wall 11. The support position of the terminal component 20 can be flexibly set according to the performance requirements of the battery cell 100, simplifying the connection structure between the terminal component 20 and the mounting wall 11 and facilitating assembly.

[0240] Referring to Figures 3 and 4, in some embodiments of this application, the pole piece 20 further includes a transition structure 22 and an insulating sealing structure 23. The transition structure 22 surrounds the pole piece body 21 and is connected to the mounting wall 11. The insulating sealing structure 23 is insulating and sealingly fitted between the transition structure 22 and the pole piece body 21.

[0241] The adapter structure 22 surrounds the entire circumference of the terminal body 21 along the mounting hole 111, thereby connecting the terminal body 21 and the mounting wall 11 in the outer peripheral area of ​​the terminal body 21. The insulating and sealing structure 23 insulates the adapter structure 22 from the terminal body 21 and seals the mating position between the adapter structure 22 and the terminal body 21. This isolates the inside and outside of the housing 10 after the adapter structure 22 is connected to the mounting wall 11, reducing the risk of electrolyte leakage from the housing 10 through the mating position between the adapter structure 22 and the terminal body 21, and reducing the risk of liquids or dust from outside the housing 10 entering the housing 10 through the mating position between the adapter structure 22 and the terminal body 21, thereby improving the reliability of the battery cell 100.

[0242] The connection method between the adapter structure 22 and the mounting wall 11 is not limited, such as welding, riveting, drilling, bonding, etc. In addition, the electrode post body 21 is connected to the electrode assembly 30, which can be achieved by the electrode assembly 30 being connected to the electrode post body 21 through the conductive part 32. The connection method between the conductive part 32 and the electrode post body 21 is not limited, such as welding, riveting, drilling, bonding, etc.

[0243] In summary, when the housing 10 includes a mounting wall 11 with a mounting hole 111 formed thereon, the electrode assembly 30 is housed within the housing 10; the electrode post component 20 is located on the same side of the electrode assembly 30 as the mounting wall 11 and is mounted at the mounting hole 111. The electrode post component 20 includes an electrode post body 21, a connecting structure 22, and an insulating sealing structure 23. The electrode post body 21 is connected to the electrode assembly 30, the connecting structure 22 surrounds the electrode post body 21 and is connected to the mounting wall 11, and the insulating sealing structure 23 is insulating and sealingly fitted within the mounting wall 11. When the adapter structure 22 is connected to the electrode body 21, the electrode component 20 includes not only the electrode body 21 connected to the electrode component, but also the adapter structure 22 connected to the mounting wall 11. An insulating and sealing structure 23 is provided between the adapter structure 22 and the electrode body 21, which plays an insulating and sealing role at the connection between the electrode body 21 and the adapter structure 22. This makes the electrode component 20 itself self-sealing, which facilitates the installation and matching of the electrode component 20 with the housing 10, and can save installation time and cost.

[0244] On the other hand, when the terminal post body 21 needs to be pressed against the sealing element placed on the mounting wall 11 to achieve the sealing of the battery cell 100, the pressure applied by the terminal post component 20 to the mounting wall 11 needs to be relatively large in order to ensure the pre-tightening force required for the seal. When the shell 10 is thin, it is easy to cause deformation or damage to the mounting wall 11. Therefore, with this setting, when installing the terminal post component 20 to the mounting wall 11, there is no need to consider the insulation and sealing issues between the adapter structure 22 and the mounting wall 11. It is only necessary to complete the reliable connection of the entire circumference (for example, the adapter structure 22 and the mounting wall 11 can be made of the same material and welded together). Therefore, it is not necessary to apply a large force to the terminal post component 20 in order to meet the sealing performance at the connection between the adapter structure 22 and the mounting wall 11. This can improve the stress deformation problem of the mounting wall 11, thereby helping to reduce the wall thickness of the mounting wall 11, reduce material costs, and reduce the weight of the battery cell 100, achieving lightweight production and improving energy density.

[0245] Furthermore, when the mounting wall 11 is the end of the housing 12 opposite to the opening, the stress at the connection between the bottom wall and the side wall of the housing 12 can be reduced, which is conducive to improving the reliability of the housing 12, reducing the wall thickness and cost of the housing 12, and reducing the weight of the battery cell 100, thus achieving lightweight production.

[0246] In the above technical solution, by making the insulating and sealing structure 23 of the terminal component 20 insulating and sealingly fitted between the adapter structure 22 and the terminal body 21, the terminal component 20 itself can have self-sealing properties, which can facilitate the installation and fitting of the terminal component 20 and the housing 10, and save installation time and cost. Since there is no need to consider the insulation and sealing issues between the adapter structure 22 and the mounting wall 11, it is only necessary to complete the reliable connection of the entire circumference. This can improve the stress deformation problem of the mounting wall 11, thereby helping to reduce the wall thickness of the mounting wall 11, reduce material costs, and reduce the weight of the battery cell 100, thus achieving lightweight production.

[0247] For example, the adapter structure 22 can be configured to match the shape of the mounting hole 111. The shape of the mounting hole 111 can be designed as an elongated shape that facilitates the passage of the pole piece 20 and minimizes the flipping angle of the pole piece 20. At the same time, the pole piece body 21 can be designed as an elongated shape that matches the shape of the adapter structure 22, so that the pole piece body 21 has a larger area to connect with the conductive part 32. Alternatively, the pole piece body 21 can be designed as a circle that does not match the shape of the adapter structure 22, thereby reducing the connection area between the pole piece body 21 and the adapter structure 22, improving the uniformity of force at the connection between the pole piece body 21 and the adapter structure 22, and thus improving the connection reliability between the pole piece body 21 and the adapter structure 22.

[0248] Referring to Figures 3 and 4, in some embodiments of this application, the adapter structure 22 is formed as an elongated strip (such as a rectangle or racetrack shape) extending along the length direction of the mounting wall 11, and the outline shape of the pole body 21 matches the outline shape of the adapter structure 22 (such as a rectangle or racetrack shape); or, the adapter structure 22 is formed as an elongated strip extending along the length direction of the mounting wall 11, and the pole body 21 is located at the length center of the adapter structure 22 and is circular.

[0249] As mentioned above, the electrode assembly 30 is connected to the electrode post component 20 through the conductive part 32. When the outline shape of the electrode post body 21 is formed into an elongated shape that matches the outline shape of the transition structure 22, the area of ​​the electrode post body 21 is larger, which is beneficial to increasing the connection area between the conductive part 32 and the electrode post body 21, thereby improving the conductivity.

[0250] When the pole body 21 is located at the center of the length of the elongated transition structure 22 and is circular, it is beneficial to reduce the connection area between the pole body 21 and the transition structure 22, improve the uniformity of force at the connection between the pole body 21 and the transition structure 22, and thus improve the connection reliability between the pole body 21 and the transition structure 22.

[0251] In the above technical solution, by matching the contour shapes of the adapter structure 22 and the electrode body 21, both being elongated, the area of ​​the electrode body 21 can be increased, which is beneficial to increasing the connection area between the conductive part 32 and the electrode body 21, thereby improving the conductivity. By setting the adapter structure 22 to be elongated and the electrode body 21 to be circular, the connection area between the electrode body 21 and the adapter structure 22 can be reduced, improving the uniformity of force at the connection between the electrode body 21 and the adapter structure 22.

[0252] Referring to FIG4, in some embodiments of this application, the insulating sealing structure 23 includes a sealing structure member, at least a portion of which is clamped between the adapter structure 22 and the pole body 21 in the inward and outward directions of the mounting wall 11.

[0253] In some examples, the sealing structure is made of a material that is both sealing and insulating, such as an elastic rubber component, so that the required sealing requirements can be met by designing the shape and position of the sealing structure.

[0254] In the embodiments of this application, the directions from the inside to the outside of the mounting wall 11, and from the outside to the inside of the mounting wall 11, are collectively referred to as the "inner and outer directions of the mounting wall 11 (e.g., the first direction F1)". "Inner side of the mounting wall 11" refers to the side of the mounting wall 11 closest to the electrode assembly 30 (or the side closest to the active material coating portion 31), and "outer side of the mounting wall 11" refers to the side of the mounting wall 11 away from the electrode assembly 30 (or the side away from the active material coating portion 31).

[0255] Referring to Figure 4, the sealing structure includes at least an axial side portion. The side of the axial side portion closest to the receiving cavity 101 is the inner side of the axial side portion, and the side of the axial side portion away from the electrode assembly 30 is the outer side of the axial side portion. One of the transition structure 22 and the electrode body 21 is partially clamped on the outer side of the axial side portion, and the other is partially clamped on the inner side of the axial side portion. Thus, the axial side portion is clamped between the transition structure 22 and the electrode body 21 in the inward and outward directions (e.g., the first direction F1) of the mounting wall 11 to achieve an axial seal between the transition structure 22 and the electrode body 21.

[0256] In the above technical solution, by setting at least a portion of the sealing structure between the adapter structure 22 and the electrode body 21 in the inner and outer directions of the mounting wall 11, an axial seal is achieved between the adapter structure 22 and the electrode body 21. The axial seal provides a more reliable sealing effect and improves the electrolyte leakage problem at the mating position of the adapter structure 22 and the electrode body 21. Furthermore, if the electrode component 20 only includes the electrode body 21, and an axial seal is provided between the electrode body 21 and the mounting wall 11, a sealing pressure needs to be applied along the axial direction of the mounting hole 111, which would result in excessive stress on the mounting wall 11. However, the embodiments of this application integrate the axial seal (such as the axial side portion) into the electrode component 20, which can reduce the axial force on the mounting wall 11, improve the reliability of the mounting wall 11, and also appropriately thin the mounting wall 11 to reduce costs and increase energy density.

[0257] Referring to FIG5, in some embodiments of this application, the insulating sealing structure 23 includes a sealing structure member, which is arranged around the periphery of the adapter structure 22 near the pole body 21.

[0258] In this embodiment, since the adapter structure 22 is arranged around the pole body 21 and connected to the mounting wall 11, the periphery of the adapter structure 22 near the pole body 21 is called the "inner ring portion of the adapter structure 22", and the periphery of the adapter structure 22 near the mounting wall 11 is called the "outer ring portion of the adapter structure 22". Therefore, the sealing structure is arranged around the periphery of the adapter structure 22 near the pole body 21, which can be understood as: the sealing structure extends around the entire circumference of the inner ring portion of the adapter structure 22, and the sealing structure can be located in the annular hole area and / or axial side area of ​​the inner ring portion of the adapter structure 22 (axial side refers to both sides in the direction of penetrating the annular hole), so as to realize that the sealing structure is arranged around the periphery of the adapter structure 22 near the pole body 21.

[0259] In the above technical solution, by placing the sealing structure in the inner ring of the adapter structure 22, the sealing structure can achieve a sealing effect throughout the entire circumference. Moreover, its position is close to the mating position between the adapter structure 22 and the pole body 21, which facilitates sealing the mating position between the adapter structure 22 and the pole body 21 through a shorter path, thereby improving the reliability of the seal. Furthermore, it helps to reduce the size of the sealing structure, reduce the sealing area, and make it easier to achieve compression sealing, making the seal less prone to failure and improving the sealing effect.

[0260] Referring to FIG4, in some embodiments of this application, a first receiving groove (not shown) communicating with the receiving cavity 101 is formed at the pole member 20. The first receiving groove is open toward the receiving cavity 101 and is at least partially surrounded by the pole member 20. The tab 33 and the adapter 34 together constitute a conductive part 32 connecting the pole body 21 and the active material coating part 31. At least a portion of the conductive part 32 is received in the first receiving groove.

[0261] That is, the pole piece 20 forms a first receiving groove, the groove wall of the first receiving groove is formed by the pole piece 20, the first receiving groove is recessed in the direction away from the active material coating part 31, and the first receiving groove is open in the direction of the active material coating part 31, so that the first receiving groove is connected to the receiving cavity 101.

[0262] In the above technical solution, by providing a first receiving groove to accommodate the conductive part 32, the space occupied by the conductive part 32 in the receiving cavity 101 can be reduced, allowing the receiving cavity 101 to have a larger space to accommodate the active material coating part 31. This is beneficial for increasing the volume of the active material coating part 31, thereby increasing the energy density of the battery cell 100. Moreover, since the first receiving groove is open towards the electrode components, the conductive part 32 can be easily inserted into the first receiving groove, reducing the difficulty of operation.

[0263] For example, referring again to FIG4, a first receiving groove is formed on the side of the electrode assembly 30 (i.e., the side facing the active material coating portion 31) of the electrode post body 21 and the adapter structure 22. The adapter structure 22 protrudes relative to the mounting wall 11 in the direction away from the electrode assembly 30 (i.e., the direction away from the active material coating portion 31), so that the first receiving groove is recessed relative to the mounting wall 11 in the direction away from the electrode assembly 30.

[0264] Therefore, by processing the adapter structure 22 into an outwardly protruding shape, a portion of the first receiving groove is formed on the side of the pole body 21 facing the electrode assembly 30, and another portion of the first receiving groove is formed on the side of the adapter structure 22 facing the electrode assembly 30. The first receiving groove has a shape that is recessed relative to the mounting wall 11 in the direction away from the electrode assembly 30, so that both the side of the pole body 21 facing the electrode assembly 30 and the side of the adapter structure 22 facing the electrode assembly 30 have space to accommodate the conductive part 32, thus facilitating the storage of the conductive part 32 to a greater extent.

[0265] In other embodiments of this application, when the adapter structure 22 does not bulge relative to the first shell wall in the direction away from the electrode assembly 30 (i.e., the direction away from the active material coating portion 31), the height difference between the adapter structure 22 and the electrode body 21 can also define a first receiving groove that is recessed relative to the mounting wall 11 in the direction away from the electrode assembly 30.

[0266] In some embodiments of this application, the surface of the electrode body 21 facing the electrode assembly 30 is the inner end face of the electrode body 21. The inner end face of the electrode body 21 participates in forming a first receiving groove, and the conductive part 32 is connected to the inner end face of the electrode body 21. That is, at least a portion of the inner end face of the electrode body 21 participates in defining the groove wall of the first receiving groove, and the conductive part 32 is connected to the portion of the inner end face of the electrode body 21 that serves as the groove wall of the first receiving groove. In the above technical solution, at least a portion of the first receiving groove is formed by the side surface of the electrode body 21 facing the electrode assembly 30, and the conductive part 32 housed in the first receiving groove can easily contact and connect to the electrode body 21, improving connection convenience and simplifying the structure.

[0267] In some embodiments of this application, the electrode body 21 has a second receiving groove (not shown in the figure), which is open to the opposite side of the receiving cavity 101. In the above technical solution, the electrode body 21 has a second receiving groove that is open to the opposite side of the receiving cavity 101, which can reduce the material used in the electrode body 21, reduce the cost, reduce the weight of the electrode body 21, and increase the energy density of the battery cell 100.

[0268] Referring to FIG5, in some embodiments of this application, the housing 10 includes a housing body 12 with an opening and a housing cover, the housing cover being disposed on the opening, the mounting wall 11 including a wall body of the housing body 12 disposed opposite to the opening, and / or, the mounting wall 11 including the housing cover.

[0269] Mounting wall 11 includes a wall body 12 opposite to the opening. That is, the electrode post 20 is mounted on the wall body 12 opposite to the opening. In this embodiment, the electrode post 20 and mounting wall 11 are located on the same side of the electrode assembly 30; that is, the electrode post 20 is located on the side where the mounting wall 11 is located, so that the electrode post 20 can be mounted at the mounting hole 111 of the mounting wall 11. For example, when the mounting wall 11 is above the electrode assembly 30, the electrode post 20 is also above the electrode assembly; when the mounting wall 11 is below the electrode assembly 30, the electrode post 20 is also below the electrode assembly 30; when the mounting wall 11 is on the side of the electrode assembly 30, the electrode post 20 is also on the same side of the electrode assembly 30.

[0270] For example, the housing 10 can be surrounded by multiple walls facing different directions, one of which is a mounting wall 11. A plane perpendicular to the through direction of the mounting hole 111 is used as the projection plane. The orthographic projection of the mounting hole 111 onto this projection plane falls entirely within the area of ​​the orthographic projection of the mounting wall 11 onto this projection plane, and the orthographic projection area of ​​the mounting hole 111 is smaller than the orthographic projection area of ​​the mounting wall 11. One or more mounting holes 111 can be provided on the mounting wall 11 to meet the installation requirements of one or more pole post components 20.

[0271] Mounting wall 11 includes a cover. That is, the electrode component 20 is mounted on the cover. The housing body 12 also has a support plate, which is located between the wall of the housing body 12 opposite to the cover and the electrode component to support and protect the electrode component.

[0272] In the above technical solution, the pole post component 20 can be provided on the wall of the housing 12 opposite to the opening, or the pole post component 20 can be provided on the housing cover, so that the pole post component 20 can be flexibly set.

[0273] In some embodiments of this application, the battery cell 100 further includes a pressure relief device 50, which is disposed on the housing 10. Exemplarily, the pressure relief device 50 may be an explosion-proof valve installed on the housing 10, or it may be integrally formed in a thinned area of ​​the housing 10. Thus, by providing the pressure relief device 50, when the pressure inside the housing 10 exceeds a preset value, the pressure can be directionally released through the pressure relief device 50, thereby improving the reliability of the battery cell 100.

[0274] For example, referring to Figure 3, the pressure relief device 50 and the terminal post component 20 are located on the same side. Since the terminal post component 20 is located on the mounting wall 11, when the pressure relief device 50 is also located on the mounting wall 11, the pressure relief device 50 and the terminal post component 20 are located on the same side, for example, both can be located on the top of the battery cell 100, or both can be located on the bottom of the battery cell 100, or both can be located on the same side of the battery cell 100, etc. This simplifies the design of other shell walls besides the mounting wall 11, and simplifies the structure and processing of the battery cell 100. The shell 10 can be formed by multiple non-coplanar walls. For example, a cuboid shell 10 is formed by six walls, one of which is the mounting wall 11. By placing the pressure relief device 50 and the terminal post component 20 on the same wall, they are located on the same side.

[0275] For example, the pressure relief device 50 and the pole member 20 are located on opposite sides. Since the pole member 20 is located on the mounting wall 11, when the pressure relief device 50 is located on a wall of the housing 10 other than the mounting wall 11, for example, the end of the housing 12 opposite to the opening is the mounting wall 11, the pressure relief device 50 is located on the mounting wall 11 opposite to the opening, or the pressure relief device 50 is located on the housing cover, then the pressure relief device 50 and the pole member 20 are located on opposite sides. Thus, there is no need to consider reducing the volume of the pole member 20 by occupying the space of the mounting wall 11, so that the shape and area of ​​the pole member 20 can be flexibly designed as needed. The housing 10 can be surrounded by multiple non-coplanar walls. For example, a cuboid housing 10 is surrounded by six walls, one of which is the mounting wall 11. The pressure relief device 50 is located on any other wall other than the mounting wall 11, and the pole member 20 is located on the mounting wall 11, then the two are located on opposite sides.

[0276] The battery device 1000 according to the second aspect embodiment of this application includes a battery cell 100 of any of the above-described schemes. It is worth noting that the battery device 1000 according to the embodiment of this application may or may not include a housing 400. Therefore, since the reliability of the battery cell 1000 according to the embodiment of this application is improved, it is beneficial to improve the performance of the battery device 1000.

[0277] For example, the battery device 1000 may further include a busbar, through which multiple battery cells 100 are connected, with at least two connected. This allows for the series and / or parallel connection of multiple battery cells 100. For instance, when multiple battery cells 100 are connected in series, the negative terminal 20 of one battery cell 100 is connected to the positive terminal 20 of the next battery cell 100 via a busbar, while the positive terminal 20 of the same battery cell 100 is connected to the negative terminal 20 of the previous battery cell 100 via another busbar.

[0278] For example, referring to FIG2, the battery device 1000 includes a housing 400, and multiple battery cells 100 are housed in the housing 400. The bottom of the housing 400 is a base plate 411. The terminal post 20 is disposed on the side of the housing 10 near the base plate 411, or on the side of the housing 10 away from the housing 400.

[0279] During the use of the battery device 1000, such as in vehicle use, the base plate 411 is located at the bottom of the housing 400 in the direction of gravity. Thus, when the terminal post 20 is located on the side of the housing 10 closest to the base plate 411, it means the terminal post 20 is located at the bottom of the housing 10 in the direction of gravity; and when the terminal post 20 is located on the side of the housing 10 away from the base plate 411, it means the terminal post 20 is located at the top of the housing 10 in the direction of gravity. Therefore, the relative position of the terminal post 20 and the base plate 411 is not limited, allowing for flexible arrangement of the battery cell 100 and the housing 400.

[0280] Specifically, when the terminal component 20 of the battery cell 100 is located on the side of the housing 10 facing the bottom plate 411, the battery cell 100 is in an inverted state, and the depressurized products are ejected in the direction away from the passenger compartment, which is safer; when the terminal component 20 of the battery cell 100 is located on the side of the housing 10 close to the bottom plate 411, the battery cell 100 is in an upright state, and the electrolyte is less likely to leak.

[0281] According to the third aspect of this application, the power-consuming device 1 includes a battery device 1000 of any of the above-described embodiments, the battery device 1000 being used to provide electrical energy to the power-consuming device 1. The power-consuming device 1 can be any of the aforementioned devices or systems using the battery device 1000. Because the performance of the battery device 1000 is improved, it is beneficial to improve the power consumption performance of the power-consuming device 1.

[0282] The battery cell 100 according to seven specific embodiments of the present application will now be described with reference to Figures 3-21.

[0283] In Embodiment 1, referring to Figures 3-6, the housing 10 has a receiving cavity 101. The housing 10 includes a housing body 12 and a housing cover. One end of the housing body 12 has an opening in the first direction F1. The housing cover is disposed on the opening of the housing body 12 to form the receiving cavity 101 together with the housing body 12. The housing cover is a mounting wall 11, and the mounting wall 11 has a mounting hole 111. The pole post component 20 is mounted on the mounting wall 11 and is disposed at the mounting hole 111.

[0284] As shown in Figure 4, the pole component 20 is a simplified self-sealing type, including a pole body 21, a connecting structure 22, and an insulating sealing structure 23. The connecting structure 22 surrounds the pole body 21, and the insulating sealing structure 23 is insulatingly fitted between the pole body 21 and the connecting structure 22, and includes a sealing structure component that seals the pole body 21 and the connecting structure 22. The connecting structure 22 is connected to the mounting wall 11.

[0285] Referring to Figure 4, the electrode assembly 30 has an active material coating portion 31 housed in the receiving cavity 101, and an electrode tab 33 connected to the active material coating portion 31. The electrode tab 33 is connected to the electrode post body 21 via an adapter piece 34. The electrode tab 33 and the adapter piece 34 constitute a conductive portion 32 connecting the active material coating portion 31 and the electrode post body 21.

[0286] Referring to Figures 5 and 6, the tab 33 includes a gathering portion 332 and a tab portion 331. The gathering portion 332 is formed by gathering multiple tab pieces 33 together at one end connected to the active material coating portion 31. The tab portion 331 is connected to the gathering portion 332 and is formed by stacking and welding multiple gathered tab pieces 33 together. The tab portion 331 and the adapter piece 34 are arranged side-by-side and connected along the second direction F2. The surface of the tab portion 331 facing the electrode body 21 is the first surface 3311, and the surface of the adapter piece 34 facing the electrode body 21 is the second surface 3401. The first surface 3311 and the second surface 3401 are flush. The tab portion 331 and the adapter piece 34 constitute the horizontal segment of the conductive portion 32. The length of the horizontal segment in the second direction F2 is a first dimension L0, which is greater than 6 mm and less than or equal to 12 mm.

[0287] Referring to Figures 5 and 6, the end face of the tab 331 facing the adapter plate 34 is formed as a first inclined surface 3312, which is inclined relative to both the first direction F1 and the second direction F2. The end face of the adapter plate 34 facing the tab 331 is formed as a second inclined surface 3402. The first inclined surface 3312 and the second inclined surface 3402 are parallel and fit together. Specifically, in the second direction F2 from the tab 331 towards the adapter plate 34, the first inclined surface 3312 and the second inclined surface 3402 extend inclinedly towards the side where the pole body 21 is located. The inclined length L of the first inclined surface 3312 and the second inclined surface 3402 along the inclined direction is 2mm-3mm. The minimum distance between the first inclined surface 3312 and the end of the tab 331 facing away from the adapter plate 34 is a first gap, which is 2mm-3mm. The adapter plate 34 and the tab 331 are fitted together by the first inclined surface 3312 and the second inclined surface 3402 and connected by ultrasonic welding.

[0288] The processing and assembly process of the battery cell 100 of this embodiment is described below with reference to Figures 17-21. Figure 17 is a schematic diagram of the structure when the tab 33 and the adapter piece 34 of the battery cell 100 according to Embodiment 1 of this application are straightened and welded together; Figure 18 is a partial schematic diagram of the structure when the tab 33 and the adapter piece 34 of the battery cell 100 according to Embodiment 1 of this application are in a straightened state; Figure 19 is a schematic diagram of the structure when the electrode assembly 30 of the battery cell 100 according to Embodiment 1 of this application is installed in the housing 10; Figure 20 is a partial schematic diagram of the structure when the adapter piece 34 of the battery cell 100 according to Embodiment 1 of this application is connected to the terminal post component 20; Figure 21 is a partial schematic diagram of the structure when the terminal post component 20 of the battery cell 100 according to Embodiment 1 of this application is connected to the housing 10.

[0289] When processing the battery cell 100, multiple electrode assemblies 30 are stacked along the thickness direction of the electrode assembly 30. The multiple electrode assemblies 30 with the same polarity are gathered, stacked, and welded together to form an electrode tab 331. As shown in Figure 17, the electrode tab 331 is straightened along the height direction (first direction F1) of the active material coating part 31. The adapter piece 34 is arranged on the side of the electrode tab 331 away from the active material coating part 31, so that the first surface 3311 is flush with the second surface 3401, and the first inclined surface 3312 of the electrode tab 331 is in contact with the second inclined surface 3402 of the adapter piece 34. The welding head 2B and the welding seat 2A of the welding device 2 are placed on both sides of the electrode tab 331 and the adapter piece 34 in the second direction F2, respectively. The electrode tab 331 and the adapter piece 34 are pre-welded together by ultrasonic welding device 2. The electrode tab 331 and the adapter piece 34 are connected as shown in Figure 18.

[0290] Next, the electrode assembly 30 is installed into the housing 10. Then, the integrally connected adapter 34 and the tab 331 are passed through the through hole 61 on the insulating support 60 located in the receiving cavity 101. The insulating film covering the electrode assembly 30 is then thermally fused to the insulating support 60, as shown in Figure 19. Next, the terminal post 20 is inverted, and one end of the adapter 34 is supported on the inner surface of the terminal post body 21 placed on the terminal post 20. The adapter 34 and the terminal post body 21 are then welded together, as shown in Figure 20. Finally, the terminal post 20 is rotated 90° so that it is positioned at the mounting hole 111 of the mounting wall 11. The periphery of the mounting hole 111 of the terminal post 20 is then welded together, as shown in Figure 21. The battery cell 100 can then be subjected to a sealing test.

[0291] In this embodiment, the battery cell 100 has the adapter 34 and the tab 331 welded together with an angled surface. The first surface 3311 of the tab 331 facing the electrode body 21 is flush with the second surface 3401 of the adapter 34 facing the electrode body 21. This can shorten the length of the tab 331, improve material utilization, reduce the probability of the tab 33 folding defects when the electrode assembly 30 is wound, improve the adaptability to the thickness of the electrode assembly 30, reduce the space occupied by the tab 331 and the adapter 34 in the receiving cavity 101, reduce the bending space of the tab 33, and improve the energy density of the battery cell 100.

[0292] Example 2, as shown in Figures 7 and 8, has a structure largely the same as Example 1, with identical components using the same reference numerals. The only difference is that in Example 1, in the second direction F2 from the tab 331 towards the adapter 34, the first inclined surface 3312 and the second inclined surface 3402 extend obliquely towards the side where the electrode body 21 is located. In Example 2, in the second direction F2 from the tab 331 towards the adapter 34, the first inclined surface 3312 and the second inclined surface 3402 extend obliquely towards the side where the active material coating portion 31 is located.

[0293] Example 3, as shown in Figure 9, has a structure that is largely the same as that of Example 1, with the same reference numerals used for the same components. The only difference is that in Example 1, the length L0 of the horizontal segment of the conductive part 32 formed by the tab 331 and the adapter 34 is greater than 6 mm and less than or equal to 12 mm, and the length of the second inclined surface 3402 in the second direction F2 is less than the length of the adapter 34. In Example 3, the length L0 of the horizontal segment of the conductive part 32 formed by the tab 331 and the adapter 34 is less than or equal to 6 mm, and the length of the second lower surface in the second direction F2 is approximately equal to the length of the adapter 34 in the second direction F2.

[0294] Example 4, as shown in Figure 10, has a structure largely the same as Example 3, with identical components using the same reference numerals. The only difference is that in Example 3, in the second direction F2 from the tab 331 towards the adapter 34, the first inclined surface 3312 and the second inclined surface 3402 extend obliquely towards the side where the electrode body 21 is located. In Example 4, in the second direction F2 from the tab 331 towards the adapter 34, the first inclined surface 3312 and the second inclined surface 3402 extend obliquely towards the side where the active material coating portion 31 is located.

[0295] Example 5, as shown in Figures 11 and 12, has a structure largely the same as Example 1, with identical components using the same reference numerals. The only difference is that in Example 1, the end face of the tab 331 facing the adapter piece 34 forms a first inclined surface 3312. In Example 5, the end face of the tab 331 facing the adapter piece 34 forms two first inclined surfaces 3312. The ends of the two first inclined surfaces 3312 away from the adapter piece 34 are connected, and the other ends of the two first inclined surfaces 3312 facing the adapter piece 34 extend obliquely towards the two side surfaces of the tab 331 in the thickness direction, respectively, and intersect with the two side surfaces of the tab 331 in the thickness direction. At this time, the two first inclined surfaces 3312 cooperate to define a V-shaped groove facing the opening of the adapter piece 34. The end of the adapter piece 34 facing the tab 331 fits into the V-shaped groove and has two second inclined surfaces 3402 that are completely fitted with the two first inclined surfaces 3312.

[0296] Example 6, as shown in Figures 13 and 14, has a structure largely the same as Example 1, with identical components using the same reference numerals. The only difference is that in Example 1, the end face of the tab 331 facing the adapter 34 forms a first inclined surface 3312. In this Example 5, the end face of the tab 331 facing the adapter 34 forms two first inclined surfaces 3312. The two first inclined surfaces 3312 are connected at one end facing the adapter 34, and the other ends of the two first inclined surfaces 3312 away from the adapter 34 extend obliquely towards the two side surfaces of the tab 331 in the thickness direction, respectively, and extend to intersect with the two side surfaces of the tab 331 in the thickness direction. At this time, the two first inclined surfaces 3312 cooperate to define a triangular protrusion protruding towards the adapter 34. The two second inclined surfaces 3402 of the adapter plate 34 facing the end of the electrode 331 cooperate to define a V-shaped groove that is opposite to the recess of the electrode 331, and the triangular protrusion of the electrode 331 is fitted into the V-shaped groove of the adapter plate 34.

[0297] Example 7, as shown in Figure 15, has a structure largely the same as Example 1, with identical components using the same reference numerals. The only differences are the shape of the end face of the tab 331 facing the adapter 34 and the shape of the adapter 34. In Example 7, the end face of the tab 331 facing the adapter 34 is flat. The adapter 34 includes an integrally formed first segment 341, a second segment 342, and a connecting segment 343. Both the first segment 341 and the second segment 342 are sheet-like or plate-like extending along the second direction F2. The first segment 341 is arranged on the side of the tab 331 away from the pole body 21, and the second segment 342 is arranged on the side of the tab 331 in the second direction F2. The surface of the second segment 342 facing the pole body 21 is flush with the first surface 3311 of the tab 331. The connecting segment 343 is disposed and connected between the first segment 341 and the second segment 342.

[0298] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A single battery cell, comprising: The housing (10) has a receiving cavity (101), and the housing (10) includes a mounting wall (11) having a mounting hole (111); The pole piece (20) is installed on the mounting wall (11) and includes a pole body (21) located at the mounting hole (111). An electrode assembly (30) is disposed in the receiving cavity (101) and includes an active material coating part (31) and an electrode tab (33) connected to the active material coating part (31). The electrode tab (33) is welded together to form an electrode tab part (331). The end face of the electrode tab part (331) facing the electrode post component (20) is a first surface (3311). The adapter piece (34) is connected between the electrode tab (331) and the electrode body (21), and the side surface of the adapter piece (34) that is welded to the electrode body (21) is the second surface (3401). In the radial direction of the mounting hole (111), the first surface (3311) and the second surface (3401) are flush.

2. The battery cell according to claim 1, wherein, The electrode tab (331) and the adapter plate (34) are arranged in sequence in the radial direction of the mounting hole (111), and the electrode tab (331) and the adapter plate (34) are connected in the axial direction of the mounting hole (111).

3. The battery cell according to claim 2, wherein, In the radial direction of the mounting hole (111), at least a portion of the end face of the tab (331) facing the adapter piece (34) is formed as a first inclined surface (3312), the first inclined surface (3312) is inclined relative to the thickness direction of the tab (331), and at least a portion of the surface of the adapter piece (34) facing the tab (331) is formed as a second inclined surface (3402), the first inclined surface (3312) and the second inclined surface (3402) are fitted and connected.

4. The battery cell according to claim 3, wherein, The first inclined plane (3312) and the second inclined plane (3402) are planes.

5. The battery cell according to claim 4, wherein, The angle between the first inclined surface (3312) and the second inclined surface (3402) and one side surface of the tab (331) in the thickness direction is greater than or equal to 20° and less than or equal to 45°.

6. The battery cell according to any one of claims 3-5, wherein, The ratio of the length of the first inclined surface (3312) along the inclined direction to the thickness of the tab (331) is greater than or equal to 2 and less than or equal to 3.

7. The battery cell according to any one of claims 3-6, wherein, The length of the first inclined surface (3312) along the inclined direction is greater than or equal to 2 mm and less than or equal to 3 mm.

8. The battery cell according to any one of claims 3-7, wherein, The total area of ​​the first inclined surface (3312) on the end face of the tab (331) facing the adapter (34) is greater than or equal to 40 mm2 and less than or equal to 60 mm2.

9. The battery cell according to any one of claims 3-8, wherein, The distance between the end of the tab (331) facing away from the adapter plate (34) and the end of the first inclined surface (3312) facing away from the adapter plate (34) is the first distance, which is greater than or equal to 2 mm and less than or equal to 3 mm.

10. The battery cell according to any one of claims 3-9, wherein, The distance between the end edge of the tab (331) facing away from the adapter (34) and the end edge of the adapter (34) facing away from the tab (331) is a first dimension, which is less than or equal to 12 mm.

11. The battery cell according to claim 10, wherein, The first dimension is greater than or equal to 8 mm and less than or equal to 10 mm.

12. The battery cell according to claim 10, wherein, The first dimension is less than or equal to 6 mm.

13. The battery cell according to claim 12, wherein, The second inclined surface (3402) extends from one end of the adapter piece (34) toward the tab (331) to the other end away from the tab (331).

14. The battery cell according to any one of claims 3-13, wherein, The number of the first inclined surface (3312) is one, and the first inclined surface (3312) extends at both ends of the mounting hole (111) in the radial direction to the two side surfaces of the tab portion (331) in the thickness direction.

15. The battery cell according to any one of claims 3-13, wherein, The end face of the tab (331) facing the adapter (34) has a plurality of first inclined surfaces (3312), which are arranged along the thickness direction of the tab (331). There are a plurality of second inclined surfaces (3402), which correspond to and fit with the plurality of first inclined surfaces (3312).

16. The battery cell according to claim 15, wherein, Multiple first inclined surfaces (3312) are sequentially connected in the thickness direction of the tab portion (331).

17. The battery cell according to claim 15 or 16, wherein, In the thickness direction of the tab (331), the inclination directions of two adjacent first inclined surfaces (3312) are opposite.

18. The battery cell according to claim 17, wherein, The end face of the tab (331) facing the adapter (34) includes two first inclined surfaces (3312). In the direction from the tab (331) towards the adapter (34), the two first inclined surfaces (3312) extend towards each other or away from each other. In the axial direction of the mounting hole (111), the adjacent ends of the two first inclined surfaces (3312) are directly connected, or, The end face of the tab (331) facing the adapter (34) further includes a connecting surface, which extends axially along the mounting hole (111), and in the axial direction of the mounting hole (111), adjacent ends of the two first inclined surfaces (3312) are connected through the connecting surface.

19. The battery cell according to any one of claims 1-18, wherein, The tab (33) further includes a gathering part (332), which is connected between the tab part (331) and the active material coating part (31), and is formed by gathering one end of a plurality of tab (33) pieces connected to the active material coating part (31).

20. The battery cell according to any one of claims 1-19, wherein, The adapter piece (34) includes a first segment (341), a second segment (342), and a connecting segment (343). The first segment (341) is located on the side of the tab (331) away from the pole body (21) and is connected to the tab (331). The second segment (342) is arranged with the tab (331) in the extending direction of the tab (331). The second segment (342) is connected to the pole body (21). The surface of the second segment (342) facing the pole body (21) is formed as the second surface (3401). The connecting segment (343) connects the first segment (341) and the second segment (342).

21. The battery cell according to any one of claims 1-20, wherein, The adapter piece (34) includes a plurality of stacked and connected adapter foils, so that the adapter piece (34) is deformable.

22. The battery cell according to any one of claims 1-21, wherein, The tab (33) is welded and / or bonded to the adapter piece (34), and the adapter piece (34) is welded and / or bonded to the pole body (21).

23. The battery cell according to any one of claims 1-22, wherein, The pole member (20) covers the mounting hole (111), and the edge of the pole member (20) is supported on the side of the mounting wall (11) away from or near the receiving cavity (101).

24. The battery cell according to claim 23, wherein, The pole component (20) further includes a transition structure (22) and an insulating sealing structure (23). The transition structure (22) surrounds the pole body (21) and is connected to the mounting wall (11). The insulating sealing structure (23) is insulating and sealingly fitted between the transition structure (22) and the pole body (21).

25. The battery cell according to claim 24, wherein, The adapter structure (22) is formed as an elongated strip extending along the length direction of the mounting wall (11), and the outline shape of the pole body (21) matches the outline shape of the adapter structure (22); or, the adapter structure (22) is formed as an elongated strip extending along the length direction of the mounting wall (11), and the pole body (21) is located at the length center of the adapter structure (22) and is circular.

26. The battery cell according to claim 24 or 25, wherein, The insulating sealing structure (23) includes a sealing structure, at least a portion of which is sandwiched between the adapter structure (22) and the pole body (21) in the inward and outward directions of the mounting wall (11).

27. The battery cell according to any one of claims 24-26, wherein, The insulating sealing structure (23) includes a sealing structure component, which is arranged around the periphery of the transition structure (22) near the pole body (21).

28. The battery cell according to any one of claims 23-27, wherein, The electrode component (20) has a first receiving groove that communicates with the receiving cavity (101). The first receiving groove is open toward the receiving cavity (101) and is at least partially surrounded by the electrode component (20). The tab (33) and the adapter (34) together constitute a conductive part (32) connecting the electrode body (21) and the active material coating part (31). At least a portion of the conductive part (32) is received in the first receiving groove.

29. The battery cell according to any one of claims 23-28, wherein, The pole body (21) has a second receiving groove, which is open away from the receiving cavity (101).

30. The battery cell according to any one of claims 1-29, wherein, The housing (10) includes a body (12) with an opening and a cover, the cover being disposed over the opening. The mounting wall (11) includes a wall body disposed opposite to the opening of the shell (12), and / or the mounting wall (11) includes the shell cover.

31. A battery device comprising a battery cell (100) according to any one of claims 1-30.

32. An electrical device comprising the battery device (1000) of claim 31.

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