Battery cell, manufacturing method and device thereof, battery, and power-consuming device

Abstract

The embodiment of the present application provides a battery cell and a manufacturing method and device thereof, a battery, and an electrical device, wherein the battery (100) comprises: a shell (11) having an opening (111); an end cap assembly (12) for closing the opening (111), the end cap assembly (12) comprising an end cap body (121) and an electrode terminal (122), the electrode terminal (122) being insulated and connected to the end cap body (121); and an electrode assembly (13) provided in the shell (11), the electrode assembly (13) being in a winding structure and comprising: a winding body (131), a first pole tab (132), and a second pole tab (133), the first pole tab (132) and the second pole tab (133) having opposite polarities and being connected to the same side of the winding body (131) along a winding axis (K) of the winding structure; wherein the first pole tab (132) is electrically connected to the electrode terminal (122), and the second pole tab (133) is electrically connected to the end cap body (121).

Description

Technical Field

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

[0002] Lithium-ion batteries have been widely used in electric vehicles due to their advantages of high energy density, high power density, many cycles and long storage time.

[0003] However, improving the performance of batteries for electric vehicles has always been a difficult problem in the industry. Summary of the Invention

[0004] According to a first aspect of the present application, a battery cell is provided, comprising:

[0005] a housing having an opening;

[0006] an end cap assembly for closing the opening, the end cap assembly comprising an end cap body and an electrode terminal, the electrode terminal being insulated and connected to the end cap body; and

[0007] An electrode assembly is provided in the housing, the electrode assembly is in a wound structure and includes: a wound body, a first electrode tab, and a second electrode tab, wherein the first electrode tab and the second electrode tab have opposite polarities and are connected to the same side of the wound body along the winding axis of the wound structure;

[0008] The first electrode tab is electrically connected to the electrode terminal, and the second electrode tab is electrically connected to the end cover body.

[0009] This embodiment leads the first electrode tab and the second electrode tab out from the same end of the wound body, and only requires electrical connection space to be reserved at one end of the electrode assembly. It also eliminates the need to set electrode terminals at both ends of the battery cell, which can effectively improve the overall energy density of the battery cell. When the capacity of the battery cell is constant, the volume of the battery cell can be reduced, making the battery easier to layout in the electrical device.

[0010] Furthermore, this battery cell features only one electrode terminal, with the first tab electrically connected to the electrode terminal and the second tab directly connected to the end cap body. This simplifies the battery cell structure and assembly process. By eliminating one electrode terminal, a larger space is created on the end cap body, making it easier to arrange injection components and pressure relief components. This also leaves ample space for temperature collection components, inter-cell busbars, and various wires. This also helps increase the cross-sectional area of ​​the electrode terminal, thereby enhancing the battery cell's current capacity. This design offers a greater advantage when the end cap body is smaller.

[0011] In some embodiments, the first electrode tab and the second electrode tab both extend along the entire circumference of the wound structure and are spaced apart in the radial direction of the wound structure.

[0012] This embodiment allows the tab to continuously extend and be wound at least one circle, and has a good connection strength with the winding body in the circumferential direction, so that the base of the tab has a good self-supporting effect. In the process of applying a circumferential force to the tab to flatten it, the tab is prevented from wrinkling, the shape of the flattened area is stabilized, and the welding effect between the first tab and the electrode terminal and the second tab and the end cover body is optimized, ensuring that the electrode assembly reliably transmits electrical energy to the outside and improves the flow capacity. In addition, the particles generated during the welding of the tabs are not likely to fall into the gap between the first and second pole pieces in the circumferential direction, which can improve the reliability of the electrode assembly and prevent the occurrence of short circuits or scratches on the pole pieces. Moreover, by providing a continuous tab, the die-cutting process of the pole piece can be simplified. At the same time, when winding to form the winding body, there is no need to align the tabs, which can simplify the process and improve the production efficiency of the electrode assembly.

[0013] In addition, the first and second tabs are radially spaced apart, with the spacing forming a liquid-conducting area. This not only spatially separates the first and second tabs for insulation, but also allows the electrolyte to penetrate into the interior of the wound body from the liquid-conducting area, ensuring the wettability of the electrode assembly and improving liquid absorption. This allows the electrolyte to fully react with the active materials on the first and second pole pieces during the battery's charge and discharge process, thereby optimizing the performance of the battery cell. The electrolyte can be guided to flow into the interior of the wound body.

[0014] In some embodiments, the electrode terminal is located at a central position of the end cap body.

[0015] This embodiment can leave a large space on the end cover body in the entire peripheral area of ​​the electrode terminal, making it easy to arrange the liquid injection components and pressure relief components on the end cover body, and also leaving ample space for arranging temperature collection components, busbars between battery cells, and various wires. It is also beneficial to increase the cross-sectional area of ​​the electrode terminal to increase the flow capacity of the battery cell.

[0016] In some embodiments, the end cap assembly further includes: an insulating assembly, disposed between the electrode terminal and the end cap body, for insulating and connecting the electrode terminal and the end cap body.

[0017] This embodiment can not only install the electrode terminal on the end cover body, but also ensure reliable insulation between the electrode terminal and the end cover body. When the end cover body plays the role of the electrode terminal, it can prevent short circuits between electrode terminals of different polarities, thereby improving the reliability of the battery cell.

[0018] In some embodiments, a first through hole is provided on the end cap body, a first groove is provided on an end of the first through hole away from the electrode assembly, the electrode terminal is provided in the first through hole, the electrode terminal includes a terminal body portion, and a first annular groove is provided on an outer side wall of the terminal body portion. The insulating assembly includes:

[0019] a first insulating ring, comprising a mating section and a limiting section connected to each other, the mating section being disposed between an inner side wall of the first through hole and an outer side wall of the terminal body, a second annular groove being disposed on a side wall of the mating section close to the electrode terminal, and the limiting section being in contact with a bottom wall of the first groove; and

[0020] The connecting ring has its outer end in the radial direction embedded in the second ring groove, and its inner end in the radial direction embedded in the first ring groove.

[0021] This embodiment connects the electrode terminal to the first insulating ring via a connecting ring. The first groove restricts the first insulating ring's freedom of movement along the winding axis toward the electrode assembly. The tight fit between the first insulating ring, the first through-hole, and the first groove also prevents the electrode terminal from moving away from the electrode assembly along the winding axis. This secures the electrode terminal to the end cap body and provides insulation between the electrode terminal and the end cap body, preventing short circuits and improving the reliability of the battery cell.

[0022] In some embodiments, the connecting ring is an insulating ring.

[0023] This embodiment can further improve the insulation between the electrode terminal and the end cap body, preventing short circuits and enhancing the reliability of the battery cell. Optionally, since the first insulating ring already provides insulation between the electrode terminal and the end cap body, the connecting ring can also be made of a metal material to improve the reliability of the connection between the electrode terminal and the first insulating ring.

[0024] In some embodiments, the electrode terminal also includes an extension portion, which is connected to the terminal main body and is located on the side of the first ring groove close to the electrode assembly. The extension portion extends radially outward along the winding structure and is used to support at least one of the first insulating ring and the connecting ring; the insulating assembly also includes: a third insulating ring, which is arranged between the extension portion and the end cover body.

[0025] The end cap assembly of this embodiment utilizes a modular insulation assembly to facilitate the processing of individual parts. It also achieves connection and insulation between the electrode terminal and the end cap body after assembly. The insulation assembly limits the relative movement of the electrode terminal and the end cap body along the winding axis, as well as the radial movement of the electrode terminal within the first through-hole, thereby ensuring a more secure installation of the electrode terminal. Furthermore, the provision of a first insulating ring, a connecting ring, and a third insulating ring fully covers all possible contact points between the electrode terminal and the end cap body, thereby improving insulation performance and enhancing the reliability of the battery cell. Furthermore, the integrated end cap assembly facilitates assembly of the battery cell.

[0026] In some embodiments, a transition assembly is further included, disposed between the end cap assembly and the electrode assembly, the transition assembly comprising:

[0027] an adapter ring configured to electrically connect the second tab to the end cap body;

[0028] an adapter plate, disposed in a hollow area enclosed by the inner wall of the adapter ring and configured to electrically connect the first tab to the electrode terminal; and

[0029] The fourth insulating ring is configured to insulate and connect the adapter ring and the adapter plate.

[0030] This embodiment provides a combined adapter assembly. During assembly, the adapter ring, adapter plate and fourth insulating ring can be assembled into an adapter assembly first. When the adapter assembly is placed on the top of the tab for welding, the relative position between the adapter ring and the adapter plate can be conveniently maintained to ensure the positioning effect during welding. Moreover, when the battery is subjected to vibration and impact during use, the adapter ring and the adapter plate form a limit with each other to prevent the welding part from loosening. In addition, the adapter ring and the adapter plate are separated by the fourth insulating ring, which can prevent a short circuit between the adapter ring and the adapter plate, thereby improving the reliability of the battery cell.

[0031] In some embodiments, a third ring groove is provided on the inner side wall of the fourth insulating ring, a fourth ring groove is provided on the outer side wall of the fourth insulating ring, the adapter plate is embedded in the third ring groove, and the adapter ring is embedded in the fourth ring groove.

[0032] This embodiment can conveniently assemble the adapter ring, the adapter plate and the fourth insulating ring into an adapter assembly, which has reliable connection, is easy to assemble, and can improve assembly efficiency. Moreover, the components are detachably connected. When the adapter assembly is electrically connected by welding or the like, if some parts are damaged, they can be conveniently disassembled and replaced without replacing the entire adapter assembly.

[0033] In some embodiments, a second groove is provided on the surface of the adapter plate facing the end cover assembly, and the first pole ear is connected to the position where the second groove is provided on the adapter plate; and / or a third groove is provided on the surface of the adapter ring facing the end cover assembly, and the second pole ear is connected to the position where the third groove is provided on the adapter ring.

[0034] This embodiment reduces the thickness of the adapter plate in the welding area by providing a second groove, so that welding can be performed directly from the outside of the adapter plate after the adapter assembly is placed on the electrode assembly, thereby simplifying the assembly process and improving the firmness of the welding to reliably achieve the electrical connection between the adapter plate and the first pole ear; and reduces the thickness of the adapter ring in the welding area by providing a third groove, so that welding can be performed directly from the outside of the adapter ring after the adapter assembly is placed on the electrode assembly, thereby simplifying the assembly process and improving the firmness of the welding to reliably achieve the electrical connection between the adapter ring and the second pole ear.

[0035] In some embodiments, the fourth insulating ring comprises:

[0036] a main body section, provided between the adapter ring and the adapter disk, and configured to insulate and connect the adapter ring and the adapter disk; and

[0037] The extension section is connected to one end of the main section close to the electrode assembly. The extension section is located between the first electrode tab and the second electrode tab and is configured to insulate the first electrode tab from the second electrode tab.

[0038] This embodiment ensures reliable insulation between the first and second tabs by extending the extended section B of the fourth insulating ring between them, preventing short circuits and improving the reliability of the battery cell. Furthermore, the insulation between the first and second tabs is achieved after the fourth insulating ring is installed, eliminating the need for additional insulating components, simplifying the structure and improving assembly efficiency.

[0039] In some embodiments, a fourth groove is provided on the surface of the end cover body away from the electrode assembly, and the second electrode tab is connected to a position on the end cover body corresponding to the fourth groove.

[0040] This embodiment reduces the thickness of the end cover body in the welding area by providing a fourth groove on the end cover body. After the end cover assembly is installed in the shell, welding can be performed directly from the outside of the end cover body, which simplifies the assembly process and improves the firmness of the welding to reliably achieve electrical connection between the end cover body and the second electrode tab.

[0041] In some embodiments, the end cap assembly further includes a first seal, a fifth groove is provided on the surface of the electrode terminal away from the electrode assembly, a second through hole is provided at the bottom of the fifth groove for injecting electrolyte, and the first seal cooperates with the fifth groove to seal the second through hole.

[0042] This embodiment places the second through-hole for electrolyte injection on the electrode terminal, eliminating the need to occupy additional space elsewhere on the end cap body. This leaves ample room for other structures on the end cap body, increases the circumferential dimension of the first seal, and facilitates connection. When the first seal and the end cap body are welded to improve sealing, welding is facilitated. Even if welding defects occur, the increased distance between the outer wall of the first seal and the second through-hole prevents electrolyte from leaking from the weld, resulting in a high tolerance for welding defects.

[0043] Moreover, for the structure in which the first electrode tab and the second electrode tab are wound along the entire circumference, the electrolyte can be directly injected into the hollow area of ​​the electrode assembly through the second through hole ' provided on the electrode terminal, making the injection process smoother; in addition, by providing the fifth groove, the thickness of the electrode terminal in the welding area is thinned, and after the end cover assembly is installed in the shell, welding can be performed directly from the outside of the end cover body, which simplifies the assembly process and improves the firmness of the welding, so as to reliably achieve electrical connection between the electrode terminal and the first electrode tab.

[0044] According to a second aspect of the present application, a battery is provided, comprising: the battery cell of the above embodiment and a box body, wherein the box body is used to accommodate the battery cell.

[0045] According to a third aspect of the present application, an electrical device is provided, comprising the battery of the above embodiment, wherein the battery is used to provide electrical energy to the electrical device.

[0046] According to a fourth aspect of the present application, a method for manufacturing a battery cell is provided, comprising:

[0047] Component providing step: providing a shell and an end cap assembly, wherein the shell has an opening, and the end cap assembly includes an end cap body and an electrode terminal, wherein the electrode terminal is insulated and connected to the end cap body;

[0048] Electrode assembly step: preparing an electrode assembly and placing the electrode assembly into a housing, wherein the electrode assembly is in a wound structure and includes: a wound body, a first electrode tab, and a second electrode tab, wherein the first electrode tab and the second electrode tab have opposite polarities and are connected to the same side of the wound body along the winding axis of the wound structure;

[0049] End cap installation steps: close the opening of the end cap assembly, and electrically connect the first electrode tab to the electrode terminal, and the second electrode tab to the end cap body.

[0050] According to a fifth aspect of the present application, a battery cell manufacturing device is provided, comprising:

[0051] A component providing device is configured to provide a housing and an end cap assembly, wherein the housing has an opening, and the end cap assembly includes an end cap body and an electrode terminal, wherein the electrode terminal is insulated and connected to the end cap body;

[0052] An electrode assembly device is configured to prepare an electrode assembly, wherein the electrode assembly is in a wound structure and includes: a wound body, a first electrode tab, and a second electrode tab, wherein the first electrode tab and the second electrode tab have opposite polarities and are connected to the same side of the wound body along the winding axis of the wound structure; and

[0053] The end cap installation device is configured to close the opening of the end cap assembly, and electrically connect the first electrode tab to the electrode terminal, and the second electrode tab to the end cap body. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0055] Figure 1This is a schematic structural diagram of some embodiments of the present application for installing a battery on a vehicle.

[0056] Figure 2 Exploded views of some embodiments of the battery of the present application.

[0057] Figure 3 This is a structural diagram of the first embodiment of the battery cell of the present application.

[0058] Figure 4 This is an exploded view of the first embodiment of the battery cell of the present application.

[0059] Figure 5 Exploded views of some embodiments of electrode assemblies.

[0060] Figure 6 for Figure 3 Longitudinal cross-sectional view of the battery cell shown.

[0061] Figure 7 for Figure 6 Enlarged view of point A.

[0062] Figure 8 for Figure 3 Schematic diagram of the structure of the connection between the middle electrode terminal and the end cover body.

[0063] Figure 9 for Figure 8 sectional view of .

[0064] Figure 10 for Figure 8 Exploded diagram of .

[0065] Figure 11 for Figure 3 Schematic diagram of the structure of some embodiments of the transfer component.

[0066] Figure 12 for Figure 11 Exploded diagram of .

[0067] Figure 13A 、 Figure 13B 、 Figure 13C and Figure 13D They are Figure 11 Cross-sectional views of four different fourth insulating rings are provided.

[0068] Figure 14 This is a structural diagram of a second embodiment of a battery cell of the present application.

[0069] Figure 15 This is an exploded view of a second embodiment of a battery cell of the present application.

[0070] Figure 16 for Figure 14 Longitudinal cross-sectional view of the battery cell shown.

[0071] Figure 17 for Figure 16 Enlarged view of point B.

[0072] Figure 18 for Figure 14 Schematic diagram of the structure of the connection between the middle electrode terminal and the end cover body.

[0073] Figure 19 for Figure 18 sectional view of .

[0074] Figure 20 for Figure 18 Exploded diagram of .

[0075] Figure 21 Flowcharts of some embodiments of the battery cell manufacturing method of the present application.

[0076] Figure 22 Schematic diagram of the module composition of some embodiments of the battery cell manufacturing device of the present application.

[0077] Marking Description:

[0078] 100. Battery cell;

[0079] 11. Housing; 111. Opening; 112. Recessed portion; 113. Bend portion; Q. Accommodating cavity;

[0080] 12. End cap assembly; 121. End cap body; 1211. First through hole; 1212. First groove; 1213. Fourth groove; 1214. Stopper; 1215. Thinning portion; 122. Electrode terminal; 122A. Terminal body; 122B. Extension portion; 1221. First annular groove; 1222. Fifth groove; 1222'. Second through hole; 123. Insulation assembly; 1231. First insulating ring; 1231'. Second annular groove; 1231A. Fitting section; 1231B. Stopper section; 1232. Connecting ring; 1233. Third insulating ring; 124. First sealing member;

[0081] 13. Electrode assembly; 131. Winding body; 132. First electrode tab; 133. Second electrode tab; 1. First electrode piece; 1A. First main body; 2. Second electrode piece; 2A. Second main body; 3. Separator; K. Winding axis;

[0082] 14. Adapter assembly; 141. Adapter plate; 1411. Second groove; 1412. Third through hole; 141A. Main body; 141B. Connecting portion; 142. Adapter ring; 1421. Third groove; 1422. Sixth groove; 143. Fourth insulating ring; 1431. Third ring groove; 1432. Fourth ring groove; 143A. Main body section; 143B. Extension section;

[0083] 15. Insulating film; 16. Second sealing member;

[0084] 200, battery; 201, housing; 201A, accommodating portion; 201B, first cover; 201C, second cover;

[0085] 300, vehicle; 301, axle; 302, wheel; 303, motor; 304, controller;

[0086] 400. Manufacturing device; 410. Component providing equipment; 420. Electrode assembly equipment; 430. End cap installation equipment. DETAILED DESCRIPTION

[0087] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0088] In the description of this application, it should be noted that, unless otherwise specified, "multiple" means more than two; the terms "upper", "lower", "left", "right", "inside", "outside", etc., indicating directions or positional relationships, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on this application.

[0089] Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Perpendicular" does not strictly refer to perpendicularity, but rather to the tolerances allowed. "Parallel" does not strictly refer to parallelism, but rather to the tolerances allowed. The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application.

[0090] It should also be noted that, in the description of this application, unless otherwise specified or limited, the terms "installed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0091] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least some embodiments of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0092] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0093] This application uses descriptions of directions or positional relationships such as "up", "down", "top", "bottom", "front", "back", "inside" and "outside" to facilitate the description of this application, and does not indicate or imply that the device referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, it should not be understood as limiting the scope of protection of this application.

[0094] Battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the present application does not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the present application does not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the present application does not limit this.

[0095] Current battery cells typically include a housing and an electrode assembly housed within the housing, which is filled with an electrolyte. The electrode assembly is primarily composed of a first electrode sheet and a second electrode sheet of opposite polarity, stacked or wound together, with a separator typically positioned between them. The portions of the first and second electrode sheets coated with active material constitute the main body of the electrode assembly, while the portions of the first and second electrode sheets uncoated with active material constitute the first and second tabs, respectively. In lithium-ion batteries, the first electrode sheet can be a positive electrode sheet, comprising a positive current collector and positive active material layers disposed on either side of the current collector. The positive current collector can be made of, for example, aluminum, and the positive active material can be, for example, lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The second electrode sheet can be a negative electrode sheet, comprising a negative current collector and negative active material layers disposed on either side of the current collector. The negative current collector can be made of, for example, copper, and the negative active material can be, for example, graphite or silicon. The first and second tabs can be located together at one end of the main body or separately at opposite ends. During the charge and discharge process of the battery cell, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs connect the terminals to form a current loop.

[0096] Current battery cells typically have a first electrode terminal and a second electrode terminal with opposite polarities for connecting to an electrical circuit for power supply. The first tab is electrically connected to the first electrode terminal, and the second tab is electrically connected to the second electrode terminal. For example, for cylindrical battery cells, due to the smaller end area of ​​the battery cell, the second tab and the second electrode terminal are respectively provided at both ends of the battery cell. Accordingly, the first tab and the second tab are respectively led out from the two ends of the electrode assembly. In practice, the inventors have found that the tabs and electrode terminals at each end occupy a certain amount of space for electrical connection, requiring more space in the height direction of the battery cell, resulting in an increase in the overall volume of the battery cell and affecting the overall energy density of the battery cell.

[0097] To increase the energy density of battery cells, the inventors came up with the idea of ​​placing the first and second electrode terminals on the same end of the battery cell, and correspondingly, extending the first and second tabs from the same end of the electrode assembly. However, this arrangement faces the following two challenges.

[0098] 1. Spatial layout issues: It would be rather crowded to set up two electrode terminals on the end cap at the same time, and the insulation of the two electrode terminals must also be considered. In addition, the end cap must be provided with a liquid injection hole, a pressure relief component, a temperature collection component, a busbar between battery cells, and various wires. When the end cap area is small, it is difficult to carry out spatial layout.

[0099] 2. Insulation issue: The first electrode terminal and the second electrode terminal are located at the same end of the battery cell and need to be reliably insulated. In addition, insulation issues must also be considered between the first and second tabs led out from the same end of the electrode assembly, and between the adapters corresponding to the first and second tabs, in order to improve the reliability of the battery cell operation.

[0100] Based on the discovery of the above problems, the inventors of the present application have improved the way in which battery cells output electrical energy, starting from the idea of ​​increasing the energy density of battery cells and improving the spatial layout on the end caps.

[0101] A battery cell comprises a housing, an end cap assembly, and an electrode assembly. The end cap assembly comprises an end cap body and an electrode terminal, which is insulated and connected to the end cap body. The electrode assembly, mounted within the housing, is a wound structure comprising a main body, a first tab, and a second tab. The first and second tabs have opposite polarities and are connected to the same side of the main body along the winding axis of the wound structure. The first tab is electrically connected to the electrode terminal, and the second tab is electrically connected to the end cap body. This type of battery cell improves overall energy density and, by eliminating an electrode terminal, simplifies the structure and assembly process. This also leaves more space on the end cap body, allowing ample room for the arrangement of various components on the end cap.

[0102] The battery cells of the embodiments of the present application are suitable for use in batteries and electrical devices using the batteries.

[0103] Electrical devices may be mobile phones, portable devices, laptop computers, electric vehicles, electric cars, ships, spacecraft, electric toys and electric tools, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc. Electric tools include metal cutting power tools, grinding power tools, assembly power tools and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers.

[0104] like Figure 1 As shown, the power-consuming device can be a vehicle 300, such as a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle; or the power-consuming device can be a drone or a ship. Specifically, the vehicle 300 may include an axle 301, wheels 302 connected to the axle 301, a motor 303, a controller 304, and a battery 200. The motor 303 is used to drive the axle 301 to rotate, and the controller 304 is used to control the operation of the motor 303. The battery 200 can be located at the bottom, front, or rear of the vehicle 300 to provide power to the motor 303 and other components of the vehicle.

[0105] like Figure 2 As shown, battery 200 includes a housing 201 and battery cells 100. In battery 200, there can be one or more battery cells 100. If there are multiple battery cells 100, the multiple battery cells 100 can be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 100. Multiple battery cells 100 can be connected in series, in parallel, or in a hybrid connection to form a battery module, and then the multiple battery modules can be connected in series, in parallel, or in a hybrid connection to form a whole unit housed in housing 201. Alternatively, all battery cells 100 can be directly connected in series, in parallel, or in a hybrid connection, and then the whole unit formed by all battery cells 100 can be housed in housing 201.

[0106] The box 201 is hollow and is used to accommodate one or more battery cells 100. The box 201 can also have different shapes and sizes depending on the shape, number, combination of the battery cells 100 to be accommodated, and other requirements. For example, the box 201 may include: a container 201A, a first cover 201B, and a second cover 201C. The container 201A has openings at both ends. The first cover 201B and the second cover 201C are respectively used to close the two end openings of the container 201A. Figure 2According to the arrangement of the plurality of battery cells 100 , the accommodation portion 201A is in a rectangular cylindrical structure.

[0107] The battery cell 100 may be, for example, a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, or a magnesium-ion battery.

[0108] In some embodiments, as Figure 3 and Figure 4 As shown, the battery cell 100 includes a housing 11 , an end cap assembly 12 and an electrode assembly 13 .

[0109] The housing 11 has an opening 111 . The end cap assembly 12 is used to close the opening 111 . The end cap assembly 12 includes an end cap body 121 and an electrode terminal 122 . The electrode terminal 122 is insulated and connected to the end cap body 121 .

[0110] The electrode assembly 13 is disposed within the housing 11. The electrode assembly 13 has a wound structure and includes a wound body 131, a first electrode tab 132, and a second electrode tab 133. The first electrode tab 132 and the second electrode tab 133 have opposite polarities and are connected to the same side of the wound body 131 along the winding axis K of the wound structure. The first electrode tab 132 is electrically connected to the electrode terminal 122, and the second electrode tab 133 is electrically connected to the end cap body 121.

[0111] The housing 11 is a hollow structure for accommodating the electrode assembly 13. The housing 11 has an opening 111, and an end cap body 121 is used to cover the opening 111. For rectangular battery cells 100, the end cap body 121 is a rectangular plate-like structure; for cylindrical battery cells 100, the end cap body 121 is a disc-shaped structure. To ensure insulation between the electrode assembly 13 and the housing 11, an insulating film 15 is provided between the electrode assembly 13 and the housing 11.

[0112] The insulated connection of the electrode terminal 122 to the end cap body 121 can be achieved in two ways: for example, by coating the portion where the electrode terminal 122 and the end cap body 121 are connected with an insulating layer, or by providing an insulating component between the electrode terminal 122 and the end cap body 121. Since the first electrode tab 132 is electrically connected to the electrode terminal 122 and the second electrode tab 133 is electrically connected to the end cap body 121, the end cap body 121 acts as an electrode terminal. The insulated connection of the electrode terminal 122 to the end cap body 121 can achieve insulation between the positive and negative electrode terminals, thereby improving the reliability of the battery cell 100. The term "electrical connection" herein includes both direct and indirect connections.

[0113] like Figure 5As shown, the electrode assembly 13 is formed by winding a first electrode sheet 1 and a second electrode sheet 2 of opposite polarity. The first electrode sheet 1 and the second electrode sheet 2 have substantially the same shape, and can be a long strip-like structure. The resulting wound structure can be cylindrical, flat, rectangular, or other shapes. The first electrode sheet 1 includes a first main body 1A and a first electrode tab 132 protruding from the first main body 1A. The first main body 1A can be coated with a first active material. The first electrode tab 132 can be provided as a single piece, or multiple pieces can be spaced apart along the winding direction. The second electrode sheet 2 includes a second main body 2A and a second electrode tab 133 protruding from the second main body 2A. The second main body 2A can be coated with a second active material. The second electrode tab 133 can be provided as a single piece, or multiple pieces can be spaced apart along the winding direction. The first and second active materials are different. For example, the first electrode sheet 1 is a positive electrode sheet, and the second electrode sheet 2 is a negative electrode sheet; or the first electrode sheet 1 is a negative electrode sheet, and the second electrode sheet 2 is a positive electrode sheet.

[0114] In this embodiment, the first electrode tab 132 and the second electrode tab 133 are led out from the same end of the winding body 131. Only electrical connection space needs to be reserved at one end of the electrode assembly 13, and the electrode terminals 122 are not required to be respectively provided at both ends of the battery cell 100. This can effectively improve the overall energy density of the battery cell 100. When the capacity of the battery cell 100 is constant, the volume of the battery cell 100 can be reduced, making it easier to layout the battery 200 in the electrical device.

[0115] Furthermore, this battery cell 100 features only one electrode terminal 122. The first tab 132 is electrically connected to the electrode terminal 122, while the second tab 133 is directly electrically connected to the end cap body 121. This simplifies the structure and assembly process of the battery cell 100. By eliminating one electrode terminal, more space is available on the end cap body 121, making it easier to arrange injection components and pressure relief components on the end cap body 121. This also leaves ample space for temperature collection components, busbars between battery cells 100, and various wires. This also helps increase the cross-sectional area of ​​the electrode terminal 122, thereby enhancing the current flow capacity of the battery cell 100. This design offers greater advantages when the end cap body 121 is relatively small.

[0116] In some embodiments, the first electrode tab 132 and the second electrode tab 133 extend along the entire circumference of the winding structure and are spaced apart in the radial direction of the winding structure.

[0117] This embodiment allows the tab to continuously extend and wind at least one turn, providing a strong connection strength with the winding body 131 in the circumferential direction, making the base of the tab more self-supporting. This prevents the tab from wrinkling during the process of applying a circumferential force to the tab, stabilizes the shape of the flattened area, and optimizes the welding effect between the first tab 132 and the electrode terminal 122, and between the second tab 133 and the end cap body 121, ensuring that the electrode assembly 13 can reliably transmit electrical energy and improving its current capacity. Furthermore, particles generated during tab welding are less likely to fall circumferentially into the gap between the first and second pole pieces 1 and 2, thereby improving the reliability of the electrode assembly 13 and preventing short circuits or scratches on the pole pieces.

[0118] Moreover, by arranging a continuous first pole ear 132 on a partial winding length of the first main body 1A and a continuous second pole ear 133 on a partial winding length of the second main body 2A, the current capacity of the first pole ear 132 and the second pole ear 133 can be met, and there is no need to arrange discrete pole ears on the entire winding length of the main body, which can simplify the die-cutting pole piece process. At the same time, when the first pole piece 1 and the second pole piece 2 are wound to form the winding body 131, there is no need to align the pole ears, which can simplify the process and improve the production efficiency of the electrode assembly 13.

[0119] In addition, the first electrode tab 132 and the second electrode tab 133 are radially spaced apart, forming a liquid guide area. No electrode tabs are provided in the liquid guide area. This not only spatially separates the first electrode tab 132 and the second electrode tab 133 to provide insulation, but also allows the electrolyte to penetrate into the interior of the wound body 131 from the liquid guide area, ensuring the wettability of the electrode assembly 13 and improving the liquid absorption effect. During the battery charging and discharging process, the electrolyte fully reacts with the active materials on the first electrode sheet 1 and the second electrode sheet 2, thereby optimizing the performance of the battery cell 100. The electrolyte can be guided to flow into the interior of the wound body 131.

[0120] On this basis, the electrode assembly 13 also includes a diaphragm 3, which is used to separate the first electrode piece 1 and the second electrode piece 2. The diaphragm 3, the first main body 1A, and the second main body 2A are wound together to form a wound body 131. In the extension direction of the winding axis K, the portion of the diaphragm 3 located in the radial spacing area extends beyond the sides of the first and second main bodies 1A and 2A. When unfolded, the diaphragm 3 can be a long strip-shaped structure. It can be made of PP (polypropylene) or PE (polyethylene) and has micro- or nano-scale pores inside, which allow metal ions to pass through during the battery's charge and discharge processes.

[0121] This structure enables the side edges of the diaphragm 3 to extend outward between the first pole piece 1 and the second pole piece 2 in the radial spacing area and be immersed in the electrolyte, thereby making it easier for the diaphragm 3 to absorb the electrolyte under capillary action, thereby improving the wetting performance of the electrode assembly 13 and thereby improving the performance of the battery cell 100.

[0122] Optionally, the first electrode tab 132 and the second electrode tab 133 may also be spaced apart along the circumference of the winding structure.

[0123] In some embodiments, as Figure 6 As shown, the electrode terminal 122 is located at the center of the end cap body 121.

[0124] For example, for a structure in which both the first pole tab 132 and the second pole tab 133 extend along the entire circumference of the winding structure, and the first pole tab 132 is located radially inward of the second pole tab 133, arranging the electrode terminal 122 at the center of the end cover body 121 can enable the first pole tab 132 to be connected to the electrode terminal 122 in the entire circumference, thereby improving the electrical connection reliability and increasing the current carrying capacity.

[0125] This embodiment arranges the electrode terminal 122 at the center of the end cover body 121, which can leave a large space in the entire peripheral area of ​​the electrode terminal 122 on the end cover body 121, making it easy to arrange the injection components and pressure relief components on the end cover body 121, and also leaving ample space for arranging the temperature collection components, the busbars between the battery cells 100, and various wires. It is also beneficial to increase the cross-sectional area of ​​the electrode terminal 122 to increase the current flow capacity of the battery cell 100.

[0126] In some embodiments, the end cap assembly 12 further includes: an insulating assembly 123 , disposed between the electrode terminal 122 and the end cap body 121 , for insulating and connecting the electrode terminal 122 and the end cap body 121 .

[0127] This embodiment provides an insulating assembly 123, which not only allows the electrode terminal 122 to be installed on the end cover body 121, but also ensures reliable insulation between the electrode terminal 122 and the end cover body 121. When the end cover body 121 acts as an electrode terminal, it can prevent short circuits between electrode terminals of different polarities, thereby improving the reliability of the battery cell 100.

[0128] In some embodiments, Figure 7 for Figure 6 A magnified image of point A, Figure 8 and Figure 9The diagrams are a schematic diagram and a cross-sectional view of the structure in which the electrode terminal 122 is connected to the end cap body 121. The end cap body 121 is provided with a first through-hole 1211. A first groove 1212 is defined at the end of the first through-hole 1211 away from the electrode assembly 13, forming a stepped hole. The electrode terminal 122 is disposed within the first through-hole 1211 and comprises a terminal body 122A with a first annular groove 1221 defined on its outer wall. The insulating assembly 123 comprises a first insulating ring 1231 and a connecting ring 1232.

[0129] The first insulating ring 1231 includes a mating section 1231A and a retaining section 1231B that are interconnected. The mating section 1231A is positioned between the inner wall of the first through-hole 1211 and the outer wall of the terminal body 122A. A second annular groove 1231' is defined on the sidewall of the mating section 1231A adjacent to the electrode terminal 122. The retaining section 1231B abuts against the bottom wall of the first groove 1212. The radially outer end of the connecting ring 1232 is embedded in the second annular groove 1231', while the radially inner end of the connecting ring 1232 is embedded in the first annular groove 1221.

[0130] The first insulating ring 1231 can be made of insulating rubber, resin or other materials.

[0131] In this embodiment, the electrode terminal 122 is connected to the first insulating ring 1231 via the connecting ring 1232. The provision of the first groove 1212 limits the freedom of movement of the first insulating ring 1231 along the winding axis K toward the electrode assembly 13. The tight fit between the first insulating ring 1231, the first through-hole 1211, and the first groove 1212 further prevents the electrode terminal 122 from moving away from the electrode assembly 13 along the winding axis K. This ensures that the electrode terminal 122 is secured to the end cap body 121 and insulated from the end cap body 121, preventing short circuits and improving the reliability of the battery cell 100.

[0132] In some embodiments, the connecting ring 1232 is an insulating ring. For example, the connecting ring 1232 is made of insulating rubber, resin, or other materials. Optionally, the first insulating ring 1231 and the connecting ring 1232 are elastic to improve the bonding strength after mating through elastic deformation.

[0133] This embodiment can further improve the insulation between the electrode terminal 122 and the end cap body 121, prevent short circuits, and enhance the reliability of the battery cell 100. Optionally, since the first insulating ring 1231 can already provide insulation between the electrode terminal 122 and the end cap body 121, the connecting ring 1232 can also be made of a metal material to enhance the reliability of the connection between the electrode terminal 122 and the first insulating ring 1231.

[0134] In some embodiments, as Figure 9 As shown, the electrode terminal 122 also includes an extension portion 122B, which is connected to the terminal main body 122A and is located on the side of the first ring groove 1221 close to the electrode assembly 13. The extension portion 122B extends radially outward along the winding structure to support at least one of the first insulating ring 1231 and the connecting ring 1232; the insulating assembly 123 also includes: a third insulating ring 1233, which is arranged between the extension portion 122B and the end cover body 121.

[0135] The third insulating ring 1233 is made of insulating rubber, resin, or other materials. The surfaces of the first insulating ring 1231 and the connecting ring 1232 facing the extension portion 122B can be flush so as to simultaneously contact the extension portion 122B. The extension portion 122B simultaneously supports the first insulating ring 1231 and the connecting ring 1232, thereby improving the stability of the installation of the insulating assembly 123.

[0136] The extension portion 122B can extend beyond the inner wall of the first through hole 1211. There is a gap between the end cover body 121 and the extension portion 122B in the direction of the winding axis K, and a third insulating ring 1233 is arranged in the gap. Through the limiting effect of the end cover body 121 on the third insulating ring 1233 and the extension portion 122B, this structure can limit the freedom of the electrode terminal 122 to move along the winding axis K toward the direction away from the electrode assembly 13.

[0137] Optionally, the radial outer end of the extension portion 122B is provided with a protrusion extending in a direction away from the electrode assembly 13. Correspondingly, a recess is provided on the third insulating ring 1233, and the protrusion is embedded in the recess to achieve the connection between the extension portion 122B and the third insulating ring 1233. This structure can prevent the third insulating ring 1233 from being displaced in the radial direction.

[0138] like Figure 10 As shown, the end cap assembly 12 of this embodiment is provided with a modular insulating assembly 123, which facilitates the processing of individual parts and also achieves connection and insulation between the electrode terminal 122 and the end cap body 121 after assembly. The insulating assembly 123 can limit the freedom of relative movement of the electrode terminal 122 and the end cap body 121 along the winding axis K, and can also limit the freedom of radial movement of the electrode terminal 122 within the first through hole 1211, thereby ensuring a more secure installation of the electrode terminal 122. Furthermore, the provision of the first insulating ring 1231, the connecting ring 1232, and the third insulating ring 1233 fully covers all possible contact points between the electrode terminal 122 and the end cap body 121, thereby improving insulation performance and enhancing the reliability of the battery cell 100. Furthermore, the integral end cap assembly 12 facilitates assembly of the battery cell 100.

[0139] In some embodiments, a fourth groove 1213 is provided on the surface of the end cap body 121 away from the electrode assembly 13 , and the second electrode tab 133 is connected to a position on the end cap body 121 corresponding to the fourth groove 1213 .

[0140] The fourth groove 1213 may extend circumferentially. For example, one fourth groove 1213 may extend partially or entirely circumferentially. Alternatively, multiple fourth grooves 1213 may be provided, and the multiple fourth grooves 1213 may be spaced apart circumferentially.

[0141] This embodiment reduces the thickness of the end cover body 121 in the welding area by providing a fourth groove 1213 on the end cover body 121. After the end cover assembly 12 is installed in the shell 11, welding can be performed directly from the outside of the end cover body 121, thereby simplifying the assembly process and improving the firmness of the welding to reliably achieve electrical connection between the end cover body 121 and the second pole ear 133.

[0142] In some embodiments, the end cap assembly 12 further includes a first seal 124, a fifth groove 1222 is provided on the surface of the electrode terminal 122 away from the electrode assembly 13, a second through hole 1222' is provided at the bottom of the fifth groove 1222 for injecting electrolyte, and the first seal 124 cooperates with the fifth groove 1222 to seal the second through hole 1222'.

[0143] The first sealing member 124 can be a sealing pin, for example, made of a rubber material. The first sealing member 124 and the second through hole 1222' can be tightly fitted, or further sealed with an adhesive. Alternatively, the first sealing member 124 can be made of a metal material, and the first sealing member 124 and the electrode terminal 122 are welded by metal.

[0144] This embodiment allows the second through-hole 1222' for injecting electrolyte to be located on the electrode terminal 122, eliminating the need to occupy additional space elsewhere on the end cap body 121. This leaves ample room for other structures on the end cap body 121 and facilitates increasing the circumferential dimension of the first sealing member 124, facilitating connection. When welding the first sealing member 124 to the end cap body 121 to improve sealing, welding is facilitated. Even if welding defects occur, the increased distance between the outer wall of the first sealing member 124 and the second through-hole 1222' prevents electrolyte from leaking out of the weld, resulting in a high tolerance for welding defects.

[0145] Moreover, for the structure in which the first pole tab 132 and the second pole tab 133 are wound along the entire circumference, the electrolyte can be directly injected into the hollow area of ​​the electrode assembly 13 through the second through hole 1222' provided on the electrode terminal 122, making the injection process smoother; in addition, by providing the fifth groove 1222, the thickness of the electrode terminal 122 in the welding area is thinned, and after the end cover assembly 12 is installed in the shell 11, welding can be performed directly from the outside of the end cover body 121, which simplifies the assembly process and improves the firmness of the welding, so as to reliably realize the electrical connection between the electrode terminal 122 and the first pole tab 132.

[0146] In some embodiments, as Figure 11 and Figure 12 As shown, the battery cell 100 further includes an adapter assembly 14, which is disposed between the end cap assembly 12 and the electrode assembly 13. The adapter assembly 14 includes an adapter ring 142, an adapter disc 141, and a fourth insulating ring 143. The adapter ring 142 is configured to electrically connect the second electrode tab 133 to the end cap body 121; the adapter disc 141 is disposed within the hollow area enclosed by the inner wall of the adapter ring 142 and is configured to electrically connect the first electrode tab 132 to the electrode terminal 122; and the fourth insulating ring 143 is configured to insulate the adapter ring 142 from the adapter disc 141.

[0147] The adapter ring 142 and adapter plate 141 are made of a conductive material, such as aluminum, copper, or other metal. For example, welding or riveting can be used to achieve electrical connection. When welding is used, the first electrode tab 132 can be welded to the adapter plate 141, and the second electrode tab 133 can be welded to the adapter ring 142. After installing the end cap assembly 12, the electrode terminal 122 can be welded to the adapter plate 141 from the outside of the end cap assembly 12, and the end cap body 121 can be welded to the adapter ring 142.

[0148] In order to prevent a short circuit between the adapter assembly 14 and the shell 11 , the outer side wall of the adapter ring 142 may be configured as a slope, the radial dimension of which gradually decreases from the electrode assembly 13 to the end cap assembly 12 along the winding axis K.

[0149] To facilitate electrolyte injection, a third through-hole 1412 is provided at the center of the adapter disc 141. This through-hole 1412 is aligned with and communicates with the second through-hole 1222', allowing for electrolyte injection after the first seal 124 is removed. Because the adapter assembly 14 is formed as a disc, placing the injection hole in the center prevents interference with other parts requiring welding or interconnection, allowing electrolyte to be injected directly into the hollow area of ​​the electrode assembly 13, facilitating a smoother injection process.

[0150] By providing the adapter assembly 14, this embodiment can reduce the requirements for the positional relationship between the first electrode tab 132 and the electrode terminal 122, and between the second electrode tab 133 and the end cap body 121, thereby reducing the difficulty of the electrical connection process. It also facilitates setting the first electrode tab 132 and the second electrode tab 133 to the same lead-out length, reducing the difficulty of processing the electrode assembly 13. Moreover, because the multiple electrode tabs are relatively fluffy, the adapter assembly 14 can more easily improve the connection reliability and increase the current carrying capacity of the inner and outer ring electrode tabs. For example, when welding is used for electrical connection, the welding trajectory between the adapter assembly 14 and the electrode tabs can be controlled, which can improve the weld strength. In addition, it can also prevent damage to the electrode tabs or the wound body 131 during electrical connection. For example, when welding is used, it can prevent the welding energy from burning the electrode tabs, deforming the wound body 131, or causing the coating on the first body portion 1A and the second body portion 2A to fall off.

[0151] In addition, by setting up a combined adapter assembly 14, the adapter ring 142, the adapter plate 141 and the fourth insulating ring 143 can be assembled into the adapter assembly 14 first during assembly. When the adapter assembly 14 is placed on the top of the pole ear for welding, the relative position between the adapter ring 142 and the adapter plate 141 can be conveniently maintained to ensure the positioning effect during welding; moreover, when the battery is subjected to vibration and impact during use, the adapter ring 142 and the adapter plate 141 form a limit with each other to prevent the welding part from loosening; in addition, the adapter ring 142 and the adapter plate 141 are separated by the fourth insulating ring 143, which can prevent a short circuit between the adapter ring 142 and the adapter plate 141, thereby improving the reliability of the battery cell 100.

[0152] In some embodiments, as Figure 13A As shown, the inner wall of the fourth insulating ring 143 is provided with a third annular groove 1431 , the outer wall of the fourth insulating ring 143 is provided with a fourth annular groove 1432 , the adapter plate 141 is embedded in the third annular groove 1431 , and the adapter ring 142 is embedded in the fourth annular groove 1432 .

[0153] Among them, the fourth insulating ring 143 can be made of insulating rubber, and the adapter plate 141 and the adapter ring 142 can be embedded in the fourth insulating ring 143 through the elastic action of the fourth insulating ring 143. Optionally, the adapter plate 141 includes a main body 141A and a connecting portion 141B, the connecting portion 141B is connected to the outer ring of the main body 141A, and the surface of the connecting portion 141B away from the electrode assembly 13 is lower than the surface of the main body 141A away from the electrode assembly 13. A sixth groove 1422 is provided at the radial inner edge of the surface of the adapter ring 142 away from the electrode assembly 13. When connected through the fourth insulating ring 143, the connecting portion 141B is flush with the bottom surface of the sixth groove 1422, and a third ring groove 1431 and a fourth ring groove 1432 of the same size can be opened, which is easy to process. Moreover, the portion of the fourth insulating ring 143 outside the third ring groove 1431 and the fourth ring groove 1432 can be located in the area jointly formed by the sixth groove 1422 and the outer side of the connecting portion 141B, so as to avoid interference between the fourth insulating ring 143 and the end cover assembly 12 and reduce the height of the battery cell 100.

[0154] This embodiment can conveniently assemble the adapter ring 142, the adapter plate 141 and the fourth insulating ring 143 into the adapter assembly 14, which has reliable connection, is easy to assemble, and can improve assembly efficiency. Moreover, the components are detachably connected. When the adapter assembly 14 is electrically connected by welding or the like, if some parts are damaged, they can be conveniently disassembled and replaced without replacing the entire adapter assembly 14.

[0155] In some embodiments, a second groove 1411 is provided on the surface of the adapter plate 141 facing the end cap assembly 12, and the first tab 132 is connected to the location on the adapter plate 141 where the second groove 1411 is provided; and / or a third groove 1421 is provided on the surface of the adapter ring 142 facing the end cap assembly 12, and the second tab 133 is connected to the location on the adapter ring 142 where the third groove 1421 is provided. For example, the electrical connection may be achieved by welding or riveting.

[0156] Among them, the second groove 1411 or the third groove 1421 can extend along the circumferential direction. For example, one second groove 1411 can be set and extend along part of the circumference or the entire circumference. The second groove 1411 can be set on the main body 141A; or multiple second grooves 1411 can be set, and multiple second grooves 1411 are arranged at intervals along the circumferential direction.

[0157] This embodiment reduces the thickness of the adapter plate 141 in the welding area by providing a second groove 1411, and can directly perform welding from the outside of the adapter plate 141 after the adapter assembly 14 is placed on the electrode assembly 13, thereby simplifying the assembly process and improving the firmness of the welding, so as to reliably achieve the electrical connection between the adapter plate 141 and the first pole ear 132; and reduces the thickness of the adapter ring 142 in the welding area by providing a third groove 1421, and can directly perform welding from the outside of the adapter ring 142 after the adapter assembly 14 is placed on the electrode assembly 13, thereby simplifying the assembly process and improving the firmness of the welding, so as to reliably achieve the electrical connection between the adapter ring 142 and the second pole ear 133.

[0158] In some embodiments, as Figures 13B to 13D As shown, the fourth insulating ring 143 includes a main section 143A and an extension section 143B. The main section 143A is disposed between the adapter ring 142 and the adapter plate 141 and is configured to insulate the adapter ring 142 and the adapter plate 141. The extension section 143B is connected to the end of the main section 143A near the electrode assembly 13 and is located between the first electrode tab 132 and the second electrode tab 133 and is configured to insulate the first electrode tab 132 from the second electrode tab 133.

[0159] The third annular groove 1431 and the fourth annular groove 1432 may be provided on the main body section 143A, and a gap may be provided between the free end of the extension section 143B and the end surface of the winding body 131. The extension section 143B may adopt different structures, such as Figure 13B , the inner and outer sides of the extension section 143B extend along the winding axis K, and the free end is arc-shaped, that is, the cross section of the extension section 143B is an inverted trapezoid; Figure 13C The inner and outer sides of the extension section 143B gradually approach each other from the main section 143A to the electrode assembly 13, and the free end is flat; Figure 13D The inner side surface and the outer side surface of the extension section 143B gradually approach and intersect in the direction from the main section 143A to the electrode assembly 13, that is, the cross section of the extension section 143B is an inverted triangle.

[0160] In this embodiment, by extending the extension 143B of the fourth insulating ring 143 between the first and second tabs 132, 133, the first and second tabs 132, 133 are reliably insulated, preventing short circuits and improving the reliability of the battery cell 100. Furthermore, after the fourth insulating ring 143 is installed, the insulation between the first and second tabs 132, 133 is achieved, eliminating the need for additional insulating components, simplifying the structure, and improving assembly efficiency.

[0161] Two specific embodiments of the battery cell 100 of the present application are given below.

[0162] Figures 3 to 13D FIG. 1 is a schematic structural diagram of a first embodiment of a battery cell 100 .

[0163] like Figure 3 and Figure 4 The battery cell 100 includes a housing 11, an end cap assembly 12, and an electrode assembly 13. The housing 11 has an opening 111, and the end cap assembly 12 is used to close the opening 111. The end cap assembly 12 includes an end cap body 121 and an electrode terminal 122 insulated and connected to the end cap body 121. The end cap body 121 is used to cover the opening 111. For example, the battery cell 100 can be cylindrical.

[0164] The electrode assembly 13 is arranged in the housing 11. Figure 4 As shown, the electrode assembly 13 has a wound structure and includes a wound body 131, a first electrode tab 132, and a second electrode tab 133 of opposite polarity. The first electrode tab 132 and the second electrode tab 133 can be wound around the entire circumference at least once. The first electrode tab 132 and the second electrode tab 133 are located at the same end along the winding axis K and are radially spaced apart, with the first electrode tab 132 located radially inward of the second electrode tab 133.

[0165] like Figure 5 As shown, the first pole piece 1 includes a first main body portion 1A and a first pole tab 132 protruding from the first main body portion 1A, and the second pole piece 2 includes a second main body portion 2A and a second pole tab 133 protruding from the second main body portion 2A. The first pole piece 1, the second pole piece 2, and the diaphragm 3 are configured to be wound around a winding axis K so that the first main body portion 1A, the second main body portion 2A, and the diaphragm 3 are superimposed to form a wound body 131. At least one side of the diaphragm 3 located in the liquid guide area 111 may extend beyond the first main body portion 1A and the second main body portion 2A.

[0166] like Figure 6 and Figure 7 As shown, the first tab 132 is electrically connected to the electrode terminal 122, and the center line of the electrode terminal 122 coincides with the winding axis K, and the second tab 133 is electrically connected to the end cap body 121. An insulating assembly 123 is provided between the electrode terminal 122 and the end cap body 121 to achieve an insulated connection between the electrode terminal 122 and the end cap body 121, as shown in FIG. Figures 8 to 10 This part of the structure has been described in detail above. For example, the electrode terminal 122 can be a negative terminal. By using a copper-aluminum composite terminal, it can be easily connected to the external circuit of the battery cell 100 and the first electrode tab 132. Therefore, the end cap body 121 is generally made of aluminum and can be directly connected to the second electrode tab 133 as the positive terminal.

[0167] like Figures 11 to 13DAn adapter assembly 14 is provided between the end cap assembly 12 and the electrode assembly 13. The adapter assembly 14 includes an adapter ring 142, an adapter disc 141, and a fourth insulating ring 143. The adapter ring 142 is configured to electrically connect the second electrode tab 133 to the end cap body 121. The adapter disc 141 is provided within the hollow area enclosed by the inner wall of the adapter ring 142 and is configured to electrically connect the first electrode tab 132 to the electrode terminal 122. The fourth insulating ring 143 is configured to insulate the adapter ring 142 and the adapter disc 141. The inner sidewall of the fourth insulating ring 143 is provided with a third annular groove 1431, and the outer sidewall of the fourth insulating ring 143 is provided with a fourth annular groove 1432. The adapter disc 141 is embedded in the third annular groove 1431, and the adapter ring 142 is embedded in the fourth annular groove 1432.

[0168] In order to achieve the fixation of the end cap assembly 12, as shown in FIG. Figure 7 and Figure 9 A recessed portion is provided on the side of the outer edge of the end cover body 121 facing the electrode assembly 13 to form a limit platform 1214 on the outer edge of the end cover body 121. When the end cover assembly 12 is installed in the opening 111 of the shell 11, the end of the shell 11 directly abuts against the limit platform 1214, and laser welding is used to seal the position where the shell 11 and the end cover body 121 cooperate.

[0169] Figures 15 to 20 This is a structural diagram of the second embodiment of the present application.

[0170] The difference between this embodiment and the first embodiment is that the fixing method of the end cover assembly 12 and the housing 11 is different. Figure 14 and Figure 15 As shown, the free end of the shell 11 covers the outer edge of the end cover assembly 12, and the shell 11 and the end cover assembly 12 are fixed by using a sealing method.

[0171] like Figure 16 and Figure 17 As shown, the shell 11 has a recessed portion 112, which is recessed inward as a whole relative to the outer wall of the shell 11 in the circumferential direction. The shell 11 forms a bent portion 113 at one end of the recessed portion 112 close to the opening 111. The bent portion 113 has an accommodating cavity Q, and the radial outer end of the end cover body 121 is embedded in the accommodating cavity Q. The battery cell 100 also includes a second seal 16, which is arranged between the bent portion 113 and the end cover body 121.

[0172] The recessed portion 112 may extend along the entire circumference of the housing 11, or multiple recessed portions 112 may be spaced apart around the circumference of the housing 11. The second sealing member 16 may be a sealing ring having a C-shaped cross-section, which is fitted over the outer end of the end cap body 121 to insulate the end cap body 121 from the housing 11. Optionally, an extension may be provided at one end of the C-shaped structure proximal to the electrode assembly 13, extending toward the electrode assembly 13 to insulate the recessed portion 112 from the internal structure of the battery cell 100. For example, the second sealing member 16 may be made of a material such as rubber.

[0173] like Figures 18 to 20 A thinning portion 1215 is provided on both the inner and outer surfaces of the outer edge of the end cover body 121 , and the second sealing member 16 can be located in the area where the thinning portion 1215 is located.

[0174] When fixing the end cover assembly 12, the second seal 16 is first sleeved on the radial outer end of the end cover assembly 12, and the end cover assembly 12 is placed into the shell 11 from the opening 111. The end cover assembly 12 rests on the recessed portion 112, and then the shell 11 is bent at one end of the recessed portion 112 close to the opening 111 to form a bent portion 113, and the bent portion 113 is wrapped around the outside of the second seal 16.

[0175] This embodiment adopts an upsetting method to achieve the fixation between the end cover assembly 12 and the shell 11. By providing a second seal 16, insulation between the end cover body 121 and the shell 11 can be achieved. In this way, when the end cover body 121 is used as an electrode terminal, the shell 11 can be de-charged, thereby improving the safety of the battery cell 100.

[0176] Secondly, the present application also provides a method for manufacturing a battery cell 100, such as Figure 20 As shown, in some embodiments, the manufacturing method includes:

[0177] S110, component providing step: providing a housing 11 and an end cap assembly 12, wherein the housing 11 has an opening 111, and the end cap assembly 12 includes an end cap body 121 and an electrode terminal 122, wherein the electrode terminal 122 is insulated and connected to the end cap body 121;

[0178] S120, electrode assembly step: preparing an electrode assembly 13 and placing the electrode assembly 13 into the housing 11. The electrode assembly 13 has a wound structure and includes: a wound body 131, a first electrode tab 132, and a second electrode tab 133. The first electrode tab 132 and the second electrode tab 133 have opposite polarities and are connected to the same side of the wound body 131 along the winding axis K of the wound structure.

[0179] S130 , end cap installation step: closing the opening 111 with the end cap assembly 12 , and electrically connecting the first electrode tab 132 to the electrode terminal 122 , and electrically connecting the second electrode tab 133 to the end cap body 121 .

[0180] Among them, S110 to S130 are executed sequentially.

[0181] In this embodiment, the first electrode tab 132 and the second electrode tab 133 are led out from the same end of the winding body 131. Only electrical connection space needs to be reserved at one end of the electrode assembly 13, and the electrode terminals 122 are not required to be respectively provided at both ends of the battery cell 100. This can effectively improve the overall energy density of the battery cell 100. When the capacity of the battery cell 100 is constant, the volume of the battery cell 100 can be reduced, making it easier to layout the battery 200 in the electrical device.

[0182] Furthermore, this battery cell 100 features only one electrode terminal 122. The first tab 132 is electrically connected to the electrode terminal 122, while the second tab 133 is directly electrically connected to the end cap body 121. This simplifies the structure and assembly process of the battery cell 100. By eliminating one electrode terminal, more space is available on the end cap body 121, making it easier to arrange injection components and pressure relief components on the end cap body 121. This also leaves ample space for temperature collection components, busbars between battery cells 100, and various wires. This also helps increase the cross-sectional area of ​​the electrode terminal 122, thereby enhancing the current flow capacity of the battery cell 100. This design offers greater advantages when the end cap body 121 is relatively small.

[0183] Finally, the present disclosure also provides a manufacturing device 400 for a battery cell 100, such as Figure 21 As shown, in some embodiments, the manufacturing apparatus 400 includes: a component providing device 410 , an electrode assembly device 420 , and an end cap installation device 430 .

[0184] The component providing device 410 is configured to provide a housing 11 and an end cap assembly 12 , wherein the housing 11 has an opening 111 , and the end cap assembly 12 includes an end cap body 121 and an electrode terminal 122 , wherein the electrode terminal 122 is insulated and connected to the end cap body 121 ;

[0185] The electrode assembly device 420 is configured to prepare an electrode assembly 13, wherein the electrode assembly 13 has a wound structure and includes: a wound body 131, a first electrode tab 132, and a second electrode tab 133, wherein the first electrode tab 132 and the second electrode tab 133 have opposite polarities and are connected to the same side of the wound body 131 along the winding axis K of the wound structure; and

[0186] The end cap installation device 430 is configured to close the opening 111 of the end cap assembly 12 , and electrically connect the first electrode tab 132 to the electrode terminal 122 , and electrically connect the second electrode tab 133 to the end cap body 121 .

[0187] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A battery cell (100), comprising: A housing (11) having an opening (111); an end cap assembly (12) for closing the opening (111), the end cap assembly (12) comprising an end cap body (121) and an electrode terminal (122), the electrode terminal (122) being insulated and connected to the end cap body (121), the end cap assembly (12) further comprising an insulating assembly (123), the insulating assembly (123) being disposed between the electrode terminal (122) and the end cap body (121) and being used to insulate and connect the electrode terminal (122) and the end cap body (121); and An electrode assembly (13) is provided in the housing (11), the electrode assembly (13) being in a wound structure and comprising: a wound body (131), a first pole tab (132), and a second pole tab (133), wherein the first pole tab (132) and the second pole tab (133) have opposite polarities and are connected to the same side of the wound body (131) along a winding axis of the wound structure; Wherein, the first electrode tab (132) is electrically connected to the electrode terminal (122), and the second electrode tab (133) is electrically connected to the end cover body (121); The end cap body (121) is provided with a first through hole (1211), and a first groove (1212) is provided at one end of the first through hole (1211) away from the electrode assembly (13). The electrode terminal (122) is provided in the first through hole (1211), and the electrode terminal (122) includes a terminal main body (122A), and a first ring groove (1221) is provided on the outer side wall of the terminal main body (122A). The insulating assembly (123) includes a first insulating ring (1231) and a connecting ring (1232), and the first insulating ring (1231) includes mutually connected matching sections. (1231A) and a limiting section (1231B), the matching section (1231A) is arranged between the inner wall of the first through hole (1211) and the outer wall of the terminal main body (122A), the matching section (1231A) is provided with a second annular groove (1231') on the side wall close to the electrode terminal (122), and the limiting section (1231B) abuts against the bottom wall of the first groove (1212); the radial outer end of the connecting ring (1232) is embedded in the second annular groove (1231'), and the radial inner end of the connecting ring (1232) is embedded in the first annular groove (1221).

2. The battery cell (100) according to claim 1, wherein: The first pole tab (132) and the second pole tab (133) both extend along the entire circumference of the winding structure and are arranged at intervals along the radial direction of the winding structure.

3. The battery cell (100) according to claim 1 or 2, wherein: The electrode terminal (122) is located at the center of the end cover body (121).

4. The battery cell (100) according to claim 1, wherein: The connecting ring (1232) is an insulating ring.

5. The battery cell (100) according to claim 4, wherein: The electrode terminal (122) further comprises an extension portion (122B), the extension portion (122B) being connected to the terminal main body portion (122A) and being located on a side of the first ring groove (1221) close to the electrode assembly (13), the extension portion (122B) extending outwardly along the radial direction of the winding structure and being used to support at least one of the first insulating ring (1231) and the connecting ring (1232); the insulating assembly (123) further comprises: The third insulating ring (1233) is provided between the extension portion (122B) and the end cover body (121).

6. The battery cell (100) according to claim 1, further comprising a transition assembly (14) provided between the end cap assembly (12) and the electrode assembly (13), the transition assembly (14) comprising: An adapter ring (142) configured to electrically connect the second electrode tab (133) to the end cover body (121); An adapter plate (141) is provided in a hollow area surrounded by the inner wall of the adapter ring (142) and is configured to electrically connect the first electrode tab (132) to the electrode terminal (122); and The fourth insulating ring (143) is configured to insulate and connect the adapter ring (142) and the adapter plate (141).

7. The battery cell (100) according to claim 6, wherein: The inner side wall of the fourth insulating ring (143) is provided with a third ring groove (1431), the outer side wall of the fourth insulating ring (143) is provided with a fourth ring groove (1432), the adapter plate (141) is embedded in the third ring groove (1431), and the adapter ring (142) is embedded in the fourth ring groove (1432).

8. The battery cell (100) according to claim 6, wherein: A second groove (1411) is provided on the surface of the adapter plate (141) facing the end cover assembly (12), and the first tab (132) is connected to the position of the adapter plate (141) where the second groove (1411) is provided; and / or A third groove (1421) is provided on the surface of the adapter ring (142) facing the end cover assembly (12), and the second pole lug (133) is connected to the position of the adapter ring (142) where the third groove (1421) is provided.

9. The battery cell (100) according to claim 6, wherein: The fourth insulating ring (143) comprises: a main body section (143A), provided between the adapter ring (142) and the adapter disk (141), and configured to insulate and connect the adapter ring (142) and the adapter disk (141); and An extension section (143B) is connected to one end of the main section (143A) close to the electrode assembly (13), and the extension section (143B) is located between the first pole ear (132) and the second pole ear (133), and is configured to insulate the first pole ear (132) and the second pole ear (133).

10. The battery cell (100) according to claim 1, wherein: A fourth groove (1213) is provided on the surface of the end cover body (121) away from the electrode assembly (13), and the second electrode tab (133) is connected to a position on the end cover body (121) corresponding to the fourth groove (1213).

11. The battery cell (100) according to claim 1, wherein: The end cap assembly (12) further comprises a first sealing member (124); a fifth groove (1222) is provided on a surface of the electrode terminal (122) away from the electrode assembly (13); a second through hole (1222') for injecting electrolyte is provided at the bottom of the fifth groove (1222); and the first sealing member (124) cooperates with the fifth groove (1222) to seal the second through hole (1222').

12. A battery (200), comprising: The battery cell (100) according to any one of claims 1 to 11; as well as The box (201) is used to accommodate the battery cell (100).

13. An electrical device comprising the battery (200) according to claim 12, wherein the battery (200) is used to provide electrical energy for the electrical device.

14. A method for manufacturing a battery cell (100), comprising: Component providing step: providing a shell (11) and an end cap assembly (12), wherein the shell (11) has an opening (111), the end cap assembly (12) includes an end cap body (121) and an electrode terminal (122), the electrode terminal (122) is insulated and connected to the end cap body (121), the end cap assembly (12) further includes an insulating assembly (123), the insulating assembly (123) is arranged between the electrode terminal (122) and the end cap body (121), and is used to insulate and connect the electrode terminal (122) and the end cap body (121), wherein a first through hole (1211) is provided on the end cap body (121), a first groove (1212) is provided at one end of the first through hole (1211) away from the electrode assembly (13), the electrode terminal (122) is arranged in the first through hole (1211), and the electrode terminal (122) includes a terminal A main body (122A), a first annular groove (1221) is provided on the outer side wall of the terminal main body (122A), the insulating assembly (123) comprises a first insulating ring (1231) and a connecting ring (1232), the first insulating ring (1231) comprises a matching section (1231A) and a limiting section (1231B) connected to each other, the matching section (1231A) is provided between the inner side wall of the first through hole (1211) and the outer side wall of the terminal main body (122A), a second annular groove (1231') is provided on the side wall of the matching section (1231A) close to the electrode terminal (122), and the limiting section (1231B) abuts against the bottom wall of the first groove (1212); the radial outer end of the connecting ring (1232) is embedded in the second annular groove (1231'), and the radial inner end of the connecting ring (1232) is embedded in the first annular groove (1221); Electrode assembly step: preparing an electrode assembly (13), and placing the electrode assembly (13) into the housing (11), wherein the electrode assembly (13) is in a wound structure and comprises: a wound body (131), a first pole tab (132), and a second pole tab (133), wherein the first pole tab (132) and the second pole tab (133) have opposite polarities and are connected to the same side of the wound body (131) along the winding axis of the wound structure; End cap installation step: closing the opening (111) with the end cap assembly (12), electrically connecting the first electrode tab (132) to the electrode terminal (122), and electrically connecting the second electrode tab (133) to the end cap body (121).

15. A battery cell (100) manufacturing device (400), comprising: A component providing device (410) is configured to provide a shell (11) and an end cap assembly (12), wherein the shell (11) has an opening (111), the end cap assembly (12) includes an end cap body (121) and an electrode terminal (122), the electrode terminal (122) is insulated and connected to the end cap body (121), and the end cap assembly (12) further includes an insulating assembly (123), the insulating assembly (123) is arranged between the electrode terminal (122) and the end cap body (121), and is used to insulate and connect the electrode terminal (122) and the end cap body (121), wherein a first through hole (1211) is provided on the end cap body (121), and a first groove (1212) is provided at one end of the first through hole (1211) away from the electrode assembly (13), the electrode terminal (122) is arranged in the first through hole (1211), and the electrode terminal (122) The terminal assembly (123) comprises a terminal main body (122A), wherein a first annular groove (1221) is provided on the outer side wall of the terminal main body (122A); the insulating assembly (123) comprises a first insulating ring (1231) and a connecting ring (1232); the first insulating ring (1231) comprises a matching section (1231A) and a limiting section (1231B) connected to each other; the matching section (1231A) is provided between the inner side wall of the first through hole (1211) and the outer side wall of the terminal main body (122A); a second annular groove (1231') is provided on the side wall of the matching section (1231A) close to the electrode terminal (122); the limiting section (1231B) abuts against the bottom wall of the first groove (1212); the radial outer end of the connecting ring (1232) is embedded in the second annular groove (1231'), and the radial inner end of the connecting ring (1232) is embedded in the first annular groove (1221); An electrode assembly device (420) is configured to prepare an electrode assembly (13), wherein the electrode assembly (13) is in a wound structure and comprises: a wound body (131), a first pole tab (132), and a second pole tab (133), wherein the first pole tab (132) and the second pole tab (133) have opposite polarities and are connected to the same side of the wound body (131) along the winding axis of the wound structure; and The end cap installation device (430) is configured to close the opening (111) with the end cap assembly (12), and electrically connect the first electrode tab (132) to the electrode terminal (122), and electrically connect the second electrode tab (133) to the end cap body (121).

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