Battery cell, battery device, and electric device

Abstract

The utility model discloses a single battery, a battery device and a power utilization device, and relates to the technical field of batteries, the single battery comprises a shell and an electrode assembly, the shell is provided with an electrode terminal, the electrode assembly is accommodated in the shell and comprises an electrode main body and a tab structure, each tab structure is connected with the electrode main body and comprises a plurality of stacked tab pieces, each tab piece comprises a first tab part, the first tab parts of the adjacent tab pieces in the same tab structure are connected, part of the tab pieces in each tab structure further comprise second tab parts connected with the first tab parts, and the second tab parts are connected with the second tab parts. The second tab part is connected with the electrode terminal; when the tab piece is in an unfolded state, the second tab part is positioned on one side, far away from the electrode main body, of the first tab part. According to the single battery disclosed by the embodiment of the utility model, the size of the tab structure formed by stacking the plurality of tab pieces can be reduced, so that the space in the shell, which is occupied by the tab structure, can be reduced, and the energy density of the single battery is favorably improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery cell, a battery device and an electric device. Background Art

[0002] In related art, a battery cell includes a housing and an electrode assembly disposed within the housing. The electrode assembly comprises an electrode body and a tab structure, which is connected to electrode terminals disposed on the housing via a current collecting component. However, the tab structure in related art hinders the improvement of the battery cell's energy density. Therefore, improving the tab structure to increase the battery cell's energy density remains a technical problem to be solved. Utility Model Content

[0003] In view of the above problems, the present invention provides a battery cell, a battery device and an electrical device, wherein the battery cell has a high energy density.

[0004] In a first aspect, the present invention provides a battery cell, comprising: a shell, the shell being provided with an electrode terminal; an electrode assembly, the electrode assembly being accommodated in the shell and comprising an electrode body and a tab structure, each of the tab structures being connected to the electrode body and comprising a plurality of tab sheets stacked together; wherein each of the tab sheets comprises a first tab portion, the first tab portions of adjacent tab sheets in the same tab structure being connected, and some of the tab sheets in each tab structure further comprising a second tab portion connected to the first tab portion, and the second tab portion being connected to the electrode terminal.

[0005] In the above technical solution, the pole tab structure includes a plurality of pole tab sheets arranged in a stacked manner, so that the heat conduction area and the flow area of ​​the pole tab structure can be made larger, so as to improve the heat conduction efficiency and the flow efficiency of the electrode body, thereby effectively reducing the temperature rise inside the electrode body, thereby improving the service life and reliability of the electrode body; and, since only some of the pole tab sheets have a second pole tab portion connected to the electrode terminal, while achieving outward heat dissipation and electrical connection of the electrode body, the volume of the pole tab structure formed by stacking a plurality of pole tab sheets can be reduced, thereby reducing the space inside the shell occupied by the pole tab structure, which is beneficial to improving the energy density of the battery cell.

[0006] In some embodiments, when the electrode tab is in the expanded state, the second electrode tab portion is located on a side of the first electrode tab portion away from the electrode body.

[0007] In the above technical solution, when the pole tab is in the expanded state, the second pole tab portion is located on the side of the first pole tab portion away from the electrode body, so that the current transmission path is more orderly, reducing the confusion and interference in the current transmission process, improving the stability and efficiency of the electrical connection, and also making the heat conduction path of the pole tab more orderly. The heat generated by the electrode body is conducted from the electrode body through the first pole tab portion to the second pole tab portion, so that the heat can be dissipated outward more smoothly.

[0008] In some embodiments, each of the electrode tabs includes a third electrode tab portion, one end of the third electrode tab portion is connected to the electrode body, the other end of the third electrode tab portion is connected to the first electrode tab portion, and the third electrode tab portion is folded on the side of the electrode body close to the electrode terminal.

[0009] In the above technical solution, by connecting one end of the third pole ear portion to the electrode body and the other end to the first pole ear portion, the connection between the first pole ear portion and the electrode body can be achieved, so that the current and heat can be transferred to the first pole ear portion more smoothly through the third pole ear portion; and, by folding the third pole ear portion with the side of the electrode body close to the electrode terminal, the overall structure of the pole ear sheet can be made compact, thereby reducing the volume of the pole ear structure formed by stacking multiple pole ear sheets, thereby reducing the space inside the shell occupied by the pole ear structure.

[0010] In some embodiments, the first electrode tab portion is bent relative to the third electrode tab portion in a curved shape, and has the second electrode tab portion. In the same electrode tab sheet, the second electrode tab portion is folded on a side of the third electrode tab portion close to the electrode terminal.

[0011] In the above technical solution, the first pole ear portion is bent relative to the third pole ear portion into a curved shape, and the second pole ear portion is provided. In the same pole ear sheet, the second pole ear portion is folded on the side of the third pole ear portion close to the electrode terminal. While achieving heat and current transfer between the third pole ear portion and the second pole ear portion, the space occupied by the pole ear sheet can be reduced, and the volume of the pole ear structure formed by stacking multiple pole ear sheets can be reduced, thereby reducing the space inside the shell occupied by the pole ear structure.

[0012] In some embodiments, a first fold extending along the second direction is provided between the first pole ear portion and the third pole ear portion, the first fold is located on one side or the middle of the electrode body along the third direction, the electrode body and the pole ear structure are arranged along the first direction, the two pole ear structures are arranged along the second direction, and the third direction, the second direction and the first direction intersect with each other.

[0013] In the above technical solution, the first fold is located on one side or the middle of the electrode body along the third direction, the electrode body and the pole ear structure are arranged along the first direction, and the two pole ear structures are arranged along the second direction. The space along the first direction, the second direction and the third direction can be fully utilized to make the overall structure of the pole ear structure and the electrode body compact, reduce the space occupied by the pole ear structure, and improve the space utilization rate inside the shell; and the first fold extending along the second direction can provide more precise positioning and guiding for the folding of the pole ear sheet. For example, during the production process, the operator can fold the first pole ear part and the third pole ear part along the first fold, so that the folded multiple pole ear sheets can be arranged more regularly in the preset position.

[0014] In some embodiments, the electrode assembly includes multiple layers of pole pieces, each of which includes a pole piece body for constituting the electrode body, and each layer of the pole pieces has the pole tab.

[0015] In the above technical solution, since each layer of electrode pieces has an electrode tab, each layer of electrode pieces can have a heat conduction channel for outward heat transfer, which can increase the heat dissipation area and flow area of ​​the electrode body to the electrode terminal, thereby improving the heat dissipation efficiency and flow efficiency of the electrode body through the electrode tab to the outside, effectively reducing the temperature rise inside the electrode body, which is beneficial to extending the service life and reliability of the electrode body.

[0016] In some embodiments, the electrode assembly includes a multilayer electrode sheet, wherein the electrode sheet includes an electrode body for constituting the electrode body, and part of the electrode sheet has the electrode tab sheet.

[0017] In the above technical solution, by having only some of the pole pieces with pole tabs, the volume of the pole tab structure formed by stacking multiple pole tabs can be reduced while achieving outward heat dissipation and electrical connection of the electrode body, thereby reducing the space inside the shell occupied by the pole tab structure, which is beneficial to improving the energy density of the battery cell.

[0018] In some embodiments, among the pole pieces of the same polarity, the proportion of the pole pieces having the pole tabs is 1 / 2 to 3 / 4.

[0019] In the above technical solution, by making the proportion of the number of layers of the pole pieces with pole tabs 1 / 2~3 / 4, the thermal conductivity area and the flow area of ​​the pole tabs and the volume of the pole tab structure can be better balanced. In this way, while making the pole tabs have better thermal conductivity efficiency and flow efficiency, the volume of the pole tab structure formed by stacking multiple pole tabs can be reduced, thereby reducing the space inside the shell occupied by the pole tab structure, which is beneficial to improving the energy density of the battery cell.

[0020] In some embodiments, the pole tab having the second pole tab portion is a second pole tab, and the remaining pole tabs except the second pole tab are all first pole tabs; wherein, the pole tab structure and the electrode body are arranged along the first direction, and when the pole tab is in the unfolded state, the height of the first pole tab in the same pole tab structure in the first direction is the same and / or the height of the second pole tab in the same pole tab structure in the first direction is the same.

[0021] In the above technical solution, when the pole tabs are in the expanded state, by making the first pole tabs in the same pole tab structure have the same height in the first direction and / or the second pole tabs in the same pole tab structure have the same height in the first direction, the current and heat distribution between the first pole tab in the same pole tab structure and / or the second pole tab in the same pole tab structure can be made more uniform, thereby reducing the possibility of overheating or damage caused by local current concentration or heat accumulation, and improving the balance of the overall current and heat distribution of the pole tab structure, which is beneficial to improving the overall performance and reliability of the battery cell.

[0022] In some embodiments, the pole tab having the second pole tab portion is a second pole tab, and the remaining pole tabs except the second pole tab are all first pole tabs; wherein, the pole tab structure and the electrode body are arranged along the first direction, and when the pole tab is in the unfolded state, the height of the first pole tab in the same pole tab structure in the first direction is different and / or the height of the second pole tab in the same pole tab structure in the first direction is different.

[0023] In the above technical solution, when the pole tab is in the expanded state, the height of the first pole tab in the same pole tab structure is different in the first direction and / or the height of the second pole tab in the same pole tab structure is different in the first direction. This can reduce the space occupied by the first pole tab in the same pole tab structure and / or the second pole tab in the same pole tab structure after stacking, and reduce the volume of the pole tab structure formed by stacking multiple pole tabs. This can reduce the space inside the shell occupied by the pole tab structure, which is beneficial to improving the energy density of the battery cell.

[0024] In some embodiments, the first pole ear portion has a first weld print area, and the first weld print areas of adjacent pole ear sheets in the same pole ear structure are welded and connected, and the second pole ear portion has a second weld print area, and the second weld print area is welded and connected to the electrode terminal or the second weld print area is welded and connected to the electrode terminal through a current collecting component.

[0025] In the above technical solution, by welding the first weld print areas of adjacent pole tabs in the same pole tab structure, the second weld print area of ​​the second pole tab portion is welded to the electrode terminal, or the second weld print area is welded to the electrode terminal through the current collecting component. This can make the connection between the adjacent pole tabs and the second pole tab portion and the electrode terminal or the current collecting component simple and have strong stability, and can also form continuous current transmission and heat transfer between the adjacent pole tabs and the second pole tab portion and the electrode terminal, thereby realizing the process of current transmission and heat transfer between the electrode body and the electrode terminal.

[0026] In some embodiments, the stacking thickness of all the first pole ear portions in the same pole ear structure is T1, and the stacking thickness of all the second pole ear portions in the same pole ear structure is T2. When the pole ear sheet is in the unfolded state, the size of the first weld print area in the second direction is c, the size of the first weld print area in the first direction is d, the size of the second weld print area in the second direction is a, and the size of the second weld print area in the first direction is b. a, b, c, d, T1, and T2 satisfy: (a*b) / (c*d)=(T1 / T2)*k, where k is in the range of 1.0~1.5. The electrode body and the pole ear structure are arranged along the first direction, and the two pole ear structures are arranged along the second direction, and the second direction intersects with the first direction.

[0027] In the above technical solution, the relationship between the dimension a of the second weld print area in the second direction, the dimension b of the second weld print area in the first direction, the dimension c of the first weld print area in the second direction, the dimension d of the first weld print area in the first direction, the stacking thickness T1 of all first pole lug portions in the same pole lug structure, and the stacking thickness T2 of all second pole lug portions in the same pole lug structure satisfies (a*b) / (c*d)=(T1 / T2)*k, where k is in the range of 1.0 to 1.5. This can better balance the flow efficiency and thermal conductivity of the pole lug sheet and the volume of multiple pole lug sheets after stacking in the same pole lug structure, so that the area of ​​the second weld print area is larger, so that the pole lug sheet has better flow efficiency and thermal conductivity, while reducing the volume of the pole lug structure formed by stacking multiple pole lug sheets, thereby reducing the space occupied by the pole lug structure in the shell.

[0028] In some embodiments, when the tab is in the expanded state, the size of the first weld print area in the second direction is c, and the size of the first weld print area in the first direction is d, c and d satisfy: c / d>3, the electrode body and the tab structure are arranged along the first direction, the two tab structures are arranged along the second direction, and the second direction intersects with the first direction.

[0029] In the above technical solution, since the dimension c of the first weld mark area in the second direction and the dimension d of the first weld mark area in the first direction satisfy c / d>3, when the tab sheet is in the unfolded state, the first weld mark area can be made slender. Since the first tab portion is bent relative to the second tab portion, a certain bending force is exerted on the bent first tab portion. The slender first weld mark area can better adapt to this bending structure, reducing the possibility of local stress concentration in the first weld mark area, thereby reducing the possibility of the first tab portion being fractured due to this bending force, especially the possibility of the first weld mark area being fractured due to the concentrated bending force, which is beneficial to extending the service life of the tab sheet. In addition, the dimension d of the first weld mark area in the first direction is small. Accordingly, when the first tab portion is bent, the dimension of the first weld mark area in the first direction can be reduced, thereby reducing the space in the housing occupied by the first tab sheet in the first direction after folding, which is beneficial to improving the energy density of the battery cell.

[0030] In some embodiments, c and d satisfy: c / d = 6~8.

[0031] In the above technical solution, by satisfying c / d=6-8 between the dimension c of the first weld print area in the second direction and the dimension d of the first weld print area in the first direction, the area and shape of the first weld print area can be well balanced, so that the area of ​​the first weld print area is larger, so that the heat conduction and flow area of ​​the first weld print area are larger, thereby making the first pole ear portion have better flow efficiency and thermal conductivity efficiency, and the first weld print area can also be made slender. In this way, when the first pole ear portion is in a bent shape, the possibility of the first pole ear portion being broken due to the concentration of bending force can be effectively reduced, thereby making the connection between adjacent pole tabs have stronger stability.

[0032] In some embodiments, the side of the second pole ear portion away from the first pole ear portion is the first side, the distance between the second weld print area and the first side is L2, a second fold extending along the second direction is provided between the first pole ear portion and the second pole ear portion, the distance between the second weld print area and the second fold is L3, the second pole ear portion has a second side oppositely arranged along the second direction, the distance between the second weld print area and the second side is L1, at least one of L1, L2 and L3 is greater than 0.5 mm, the electrode body and the pole ear structure are arranged along the first direction, the two pole ear structures are arranged along the second direction, and the second direction intersects with the first direction.

[0033] In the above technical solution, by making at least one of the distance L1 between the second weld print area and the second side, the distance L2 between the second weld print area and the first side, and the distance L3 between the second weld print area and the second fold greater than 0.5 mm, the distance between the second weld print area and the first side, the second side, or the second fold of the second pole ear portion can be made larger. During the assembly process, the distance between the second weld print area and the side of the second pole ear portion can provide a certain operating space for the operator, so as to facilitate the press-fitting operation of the second pole tab sheet and reduce deformation or damage of the second weld print area.

[0034] In some embodiments, at least one of L1, L2, and L3 has a value range of 1.0 to 3.0 mm.

[0035] In the above technical solution, by having at least one of L1, L2, and L3 have a value range of 1.0 to 3.0 mm, the area of ​​the second pole ear portion and the area of ​​the second weld print area can be better balanced. While making the area of ​​the second weld print area larger so that the second pole ear sheet has better flow efficiency and thermal conductivity, the area of ​​the second pole ear portion can be made smaller, which is beneficial to reducing the weight of the pole ear structure and reducing manufacturing costs.

[0036] In some embodiments, a second fold extending along the second direction is provided between the first pole ear portion and the second pole ear portion, and a distance between the first weld print area and the second fold is L5. The pole ear sheet has a first fold extending along the second direction, and the first fold is located between the first pole ear portion and the electrode body. A distance between the first weld print area and the first fold is L6. The first pole ear portion has a third side edge arranged opposite to each other along the second direction, and a distance between the first weld print area and the third side edge is L4. At least one of L4, L5, and L6 is greater than 0.5 mm.

[0037] In the above technical solution, by making at least one of the distance L4 between the first weld print area and the third side, the distance L5 between the first weld print area and the second fold, and the distance L6 between the first weld print area and the first fold greater than 0.5 mm, the distance between the first weld print area and the third side, the first fold, or the second fold of the first tab portion can be made larger. During the assembly process, this distance between the first weld print area and the third side, the first fold, or the second fold can provide a certain operating space for the operator, thereby facilitating the press-fitting operation of the first tab sheet and reducing deformation or damage of the first weld print area.

[0038] In some embodiments, at least one of L4, L5, and L6 has a value range of 1.0 to 3.0 mm.

[0039] In the above technical solution, by having at least one of L4, L5, and L6 have a value range of 1.0 to 3.0 mm, the distance between the first weld mark area and the side of the first pole ear portion and the area of ​​the first pole ear portion when in the unfolded state can be better balanced. While making the distance between the first weld mark area and the side of the first pole ear portion larger to facilitate the press-fitting operation of the first pole ear portion, the area of ​​the first pole ear portion can be made smaller, which is beneficial to reducing the weight of the pole ear structure and reducing manufacturing costs.

[0040] In some embodiments, the method includes: a current collecting component disposed in the housing; and the second electrode tab is connected to the electrode terminal via the current collecting component.

[0041] In the above technical solution, the shell can support and protect the electrode assembly and the current collecting component, reduce the wear of the current collecting component caused by external impact, and help extend the overall service life of the battery cell. The second pole ear is connected to the electrode terminal through the current collecting component, which can achieve heat transfer and electrical connection between the second pole ear and the electrode terminal through the current collecting component, thereby achieving electrical connection between the electrode body and the electrode terminal, and also achieving heat dissipation of the electrode body to the outside of the shell through the electrode terminal.

[0042] In a second aspect, the present invention provides a battery device, comprising: a box; and a battery cell according to the embodiment of the first aspect of the present invention, wherein the battery cell is disposed in the box.

[0043] In the above technical solution, by providing the above battery cells, the battery device can have higher reliability and better performance.

[0044] In a third aspect, the present invention provides an electrical device, comprising the battery device according to the embodiment of the second aspect of the present invention.

[0045] In the above technical solution, by providing the above battery device, the electrical device can have higher reliability and better performance.

[0046] Additional aspects and advantages of the present invention will be given in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0048] Figure 1 is a schematic diagram of a battery cell according to some embodiments of the present invention;

[0049] Figure 2 yes Figure 1 Exploded view of the battery cell in the figure;

[0050] Figure 3 yes Figure 2 A schematic diagram of a battery cell from another angle;

[0051] Figure 4 yes Figure 3 Sectional view along line GG;

[0052] Figure 5 yes Figure 4 Enlarged view of point H in the middle;

[0053] Figure 6 yes Figure 2 A schematic diagram of an electrode assembly in a battery cell;

[0054] Figure 7 yes Figure 6 Enlarged view of point C in the middle;

[0055] Figure 8 yes Figure 6 A schematic diagram of the electrode assembly from another angle;

[0056] Figure 9 yes Figure 8 Enlarged view of point D in the middle;

[0057] Figure 10 yes Figure 6 A schematic diagram of the electrode assembly at another angle;

[0058] Figure 11 yes Figure 10 Enlarged view of point E in the middle;

[0059] Figure 12 is a schematic diagram of an electrode assembly in a battery cell according to some embodiments of the present invention;

[0060] Figure 13 yes Figure 12 Enlarged view of point F in the middle;

[0061] Figure 14 is a schematic diagram of an electrode assembly in a battery cell according to other embodiments of the present invention;

[0062] Figure 15 is a schematic diagram of an electrode assembly in a battery cell according to some other embodiments of the present invention;

[0063] Figure 16 is a simplified schematic diagram of a battery device according to some embodiments of the present invention;

[0064] Figure 17is a simplified schematic diagram of an electrical device according to some embodiments of the present invention.

[0065] Reference numerals:

[0066] 1000. Electrical devices;

[0067] 100. Battery device;

[0068] 10. Box body;

[0069] 20. Battery cells;

[0070] 21. Housing; 22. Current collecting component; 23. Electrode terminal;

[0071] 3. Electrode assembly; 31. Electrode body; 32. Tab structure; 321. Tab sheet; 322. First tab portion; 3221. First weld mark area; 3222. Third side edge; 323. Second tab portion; 3231. Second weld mark area; 3232. First side edge; 3233. Second side edge; 324. Third tab portion; 325. First crease; 326. Second crease;

[0072] 200. Car body. DETAILED DESCRIPTION

[0073] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0074] Unless otherwise defined, all technical and scientific terms used in this utility model have the same meanings as those commonly understood by those skilled in the art to which this utility model belongs. The terms used in the specification of the application of this utility model are only for the purpose of describing specific embodiments and are not intended to limit this utility model. The terms "including" and "having" and any variations thereof in the specification and claims of this utility model and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this utility model or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0075] Reference to an "embodiment" in this disclosure means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the disclosure. 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.

[0076] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on specific circumstances.

[0077] In this application, the term "and / or" simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Furthermore, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0078] In the embodiments of the present invention, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of the present invention, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are for illustrative purposes only and do not constitute any limitation on the present invention.

[0079] The term “plurality” used in this invention refers to two or more (including two).

[0080] In the embodiments of the present invention, unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form a new technical solution.

[0081] In the embodiments of the present invention, unless otherwise specified, all technical features and optional technical features of the present invention can be combined with each other to form a new technical solution.

[0082] In embodiments of the present invention, a battery apparatus may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or parallel via a busbar. For example, a battery cell assembly is typically formed by arranging multiple battery cells; a battery cell assembly may be a battery module, which is formed by arranging and securing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells using cable ties.

[0083] The battery device may be a battery pack, which includes a housing and one or more battery cell assemblies housed within the housing. The battery cell assemblies may be battery modules, which may be housed within the housing by securing the battery module within the housing. Alternatively, the battery cell assembly may be housed within the housing by directly securing multiple battery cells to the housing.

[0084] In an embodiment of the present invention, the housing may include a first housing and a second housing. The first housing and the second housing engage to form an enclosed space within the housing to accommodate the battery cell assembly. Enclosed herein means covered or closed, and may be sealed or unsealed. The first housing may be a top cover or a bottom plate. For example, the housing may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame to form an enclosed space within the housing to accommodate the battery cell assembly.

[0085] In an embodiment of the present invention, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0086] In the embodiments of the present invention, the battery cells may be secondary batteries, which are batteries that can be recharged to activate the active materials after discharge and continue to be used. The battery cells may be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., and the embodiments of the present invention are not limited to this. The battery cells may be cylindrical, flat, rectangular, or other shapes, and the embodiments of the present invention are not limited to this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of the present invention are not limited to this.

[0087] A battery cell is the smallest energy unit in a battery device. It includes a housing and an electrode assembly disposed within the housing. The electrode assembly is the component within the battery cell where the electrochemical reaction occurs. The housing may contain one or more electrode assemblies. The electrode assembly is primarily formed by winding or stacking positive and negative electrode sheets, and a separator is typically provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly, while the portions of the positive and negative electrode sheets without active material each constitute a tab.

[0088] The positive electrode sheet may include a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, wherein the positive electrode film layer includes a positive electrode active material.

[0089] As an example, the positive electrode current collector has two surfaces opposite to each other in its thickness direction, and the positive electrode film layer is disposed on either or both of the two opposite surfaces of the positive electrode current collector.

[0090] As an example, the positive electrode current collector may be a metal foil or a composite current collector.

[0091] The negative electrode sheet may include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, wherein the negative electrode film layer includes a negative electrode active material.

[0092] As an example, the negative electrode current collector has two surfaces opposite to each other in its thickness direction, and the negative electrode film layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0093] As an example, the negative electrode current collector may be a metal foil, a foamed metal, or a composite current collector.

[0094] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. As the application of power batteries continues to expand, market demand is also growing.

[0095] In the prior art, a battery cell includes a housing and an electrode assembly disposed within the housing. The electrode assembly includes an electrode body and a tab structure, which is connected to electrode terminals disposed on the housing via a current collecting component. However, the tab structure in the prior art includes multiple tabs stacked together. Due to the structural limitations of the tabs themselves, the resulting tab structure is relatively large, occupying a large space within the housing, which affects the energy density of the battery cell.

[0096] Based on this, the utility model proposes a battery cell, including a shell, a current collecting component and an electrode assembly, the shell is provided with an electrode terminal, the electrode assembly is accommodated in the shell and the electrode assembly includes an electrode body and a pole lug structure, each pole lug structure is connected to the electrode body and includes a plurality of pole lug sheets stacked, wherein each pole lug sheet includes a first pole lug portion, the first pole lug portions of adjacent pole lug sheets in the same pole lug structure are connected, and some pole lug sheets in each pole lug structure also include a second pole lug portion connected to the first pole lug portion, and the second pole lug portion is connected to the electrode terminal.

[0097] In the above-mentioned battery cell, the pole tab structure includes a plurality of pole tab sheets arranged in a stacked manner, so that the heat conduction area and the flow area of ​​the pole tab structure can be made larger, so as to improve the heat conduction efficiency and the flow efficiency of the electrode body, thereby effectively reducing the temperature rise inside the electrode body, thereby improving the service life and reliability of the electrode body; and, since only some of the pole tab sheets have a second pole tab portion connected to the electrode terminal, while achieving outward heat dissipation and electrical connection of the electrode body, the volume of the pole tab structure formed by stacking a plurality of pole tab sheets can be reduced, thereby reducing the space inside the shell occupied by the pole tab structure, which is beneficial to improving the energy density of the battery cell.

[0098] The battery device disclosed in the embodiments of the present invention can be used in electrical equipment that uses the battery device as a power source or various energy storage systems that use the battery device as an energy storage element. In addition to being used in vehicles, the battery device can also be used in, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery cars, electric cars, ships, spacecraft, and the like. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like, and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0099] The power-consuming device disclosed in the embodiments of the present invention may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device is provided inside the vehicle, and the battery device may be provided at the bottom, head or tail of the vehicle. The battery device may be used to power the vehicle, for example, the battery device may serve as an operating power source for the vehicle. The vehicle may further include a controller and a motor, and the controller is used to control the battery device to power the motor, for example, for the starting, navigation and working power requirements of the vehicle during driving. In some embodiments of the present invention, the battery device may serve not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0100] Reference below Figures 1-17 A battery cell 20 according to an embodiment of the present invention is described.

[0101] First, refer to Figures 1-6 The present invention provides a battery cell 20, including a shell 21 and an electrode assembly 3, the shell 21 is provided with an electrode terminal 23, the electrode assembly 3 is accommodated in the shell 21 and the electrode assembly 3 includes an electrode body 31 and a pole ear structure 32, each pole ear structure 32 is connected to the electrode body 31 and the pole ear structure 32 includes a plurality of pole ear sheets 321 arranged in a stacked manner, wherein each pole ear sheet 321 includes a first pole ear portion 322 connected to the electrode body 31, the first pole ear portions 322 of adjacent pole ear sheets 321 in the same pole ear structure 32 are connected, and some pole ear sheets 321 in each pole ear structure 32 also include a second pole ear portion 323 connected to the first pole ear portion 322, and the second pole ear portion 323 is connected to the electrode terminal 23.

[0102] For example, the first direction may refer to the X direction in the drawings, the second direction may refer to the Y direction in the drawings, and the third direction may refer to the Z direction in the drawings.

[0103] The housing 21 supports and protects the electrode assembly 3, reducing wear on the electrode assembly 3 caused by external impacts, and thus extending the overall service life of the battery cell 20. The first tab portions 322 of adjacent tabs 321 within the same tab structure 32 are connected, enabling heat transfer and electrical connection between the adjacent tabs 321. Furthermore, the second tab portions 323 of some tabs 321, connected to the first tab portions 322, are connected to the electrode terminals 23, enabling heat transfer and electrical connection between the first tab portions 322 and the electrode terminals 23 via the second tab portions 323. This allows for electrical connection between the electrode body 31 and the electrode terminals 23, as well as heat dissipation from the electrode body 31 to the exterior of the housing 21 via the electrode terminals 23.

[0104] For example, there are two tab structures 32 , and the polarities of the two tab structures 32 are different.

[0105] For example, the connection between the second electrode lug 323 and the electrode terminal 23 may be a direct connection between the second electrode lug 323 and the electrode terminal 23 , or a connection between the second electrode lug 323 and the electrode terminal 23 via the current collecting component 22 .

[0106] The tab structure 32 includes multiple tabs 321 stacked together, which increases the thermal conductivity and flow area of ​​the tab structure 32, thereby improving the thermal conductivity and flow efficiency of the electrode body 31. This results in a higher heat dissipation efficiency of the electrode body 31, effectively reducing the temperature rise within the electrode body 31, and thus improving the service life and reliability of the electrode body 31. Since some of the tabs 321 in each tab structure 32 include a second tab portion 323 connected to the first tab portion 322 and connected to the electrode terminal 23, compared to a case where every tab 321 includes a second tab portion 323, this optimizes space utilization within the housing 21 while achieving heat dissipation and electrical connection from the electrode body 31. Since only some of the tabs 321 include the second tab portion 323, the volume of the tab structure 32 formed by the stacked multiple tabs 321 can be reduced, thereby reducing the space within the housing 21 occupied by the tab structure 32, which helps improve the energy density of the battery cell 20.

[0107] For example, the pole ear structure 32 is located on one side of the electrode body 31 along the first direction. When the volume of the battery cell 20 is the same, by having only part of the pole ear sheets 321 with the second pole ear portion 323, the volume of the pole ear structure 32 formed by stacking multiple pole ear sheets 321 can be reduced, thereby reducing the space occupied by the pole ear structure 32 in the first direction. The saved space can be used to place a larger electrode body 31, which can improve the utilization rate of the internal space of the shell 21 and is also beneficial to improving the energy density of the battery cell 20.

[0108] In the above technical solution, the pole ear structure 32 includes a plurality of pole ear sheets 321 that are stacked, so that the heat conduction area and the flow area of ​​the pole ear structure 32 can be made larger, so as to improve the heat conduction efficiency and the flow efficiency of the electrode body 31, thereby effectively reducing the temperature rise inside the electrode body 31, thereby improving the service life and reliability of the electrode body 31; and, since only part of the pole ear sheets 321 have the second pole ear portion 323 connected to the electrode terminal 23, while achieving outward heat dissipation and electrical connection of the electrode body 31, the volume of the pole ear structure 32 formed by stacking a plurality of pole ear sheets 321 can be reduced, thereby reducing the space inside the shell 21 occupied by the pole ear structure 32, which is beneficial to improving the energy density of the battery cell 20.

[0109] In some embodiments, reference Figures 6-11 When the electrode tab 321 is in the unfolded state, the second electrode tab portion 323 is located on a side of the first electrode tab portion 322 away from the electrode body 31 .

[0110] When the tab 321 is in the expanded state, the second tab portion 323 is located on the side of the first tab portion 322 away from the electrode body 31. This allows current to flow from the electrode body 31, through the first tab portion 322, to the second tab portion 323, and finally through the current collecting component 22 to electrically connect with the electrode terminal 23. This creates a more orderly current transmission path, reduces confusion and interference during current transmission, reduces resistance, and improves the stability and efficiency of the electrical connection. Furthermore, when the battery cell 20 is operating, heat generated by the electrode body 31 is transferred from the electrode body 31 through the first tab portion 322 to the second tab portion 323, where it can be dissipated more effectively to the external environment. This also creates a more orderly heat conduction path through the tab 321, allowing heat to dissipate more smoothly.

[0111] In addition, the second pole ear portion 323 is located on the side of the first pole ear portion 322 away from the electrode body 31, making the structure of the pole ear piece 321 more regular, facilitating assembly and connection operations during the battery manufacturing process, and reducing the possibility of connection errors caused by structural confusion.

[0112] In the above technical solution, when the pole ear piece 321 is in the expanded state, the second pole ear portion 323 is located on the side of the first pole ear portion 322 away from the electrode body 31, so that the current transmission path is more orderly, reducing the confusion and interference in the current transmission process, improving the stability and efficiency of the electrical connection, and also making the heat conduction path of the pole ear piece 321 more orderly. The heat generated by the electrode body 31 is conducted from the electrode body 31 through the first pole ear portion 322 to the second pole ear portion 323, so that the heat can be dissipated outward more smoothly.

[0113] In some embodiments, reference Figure 5-Figure 9 Each pole ear piece 321 includes a third pole ear portion 324 , one end of the third pole ear portion 324 is connected to the electrode body 31 , and the other end of the third pole ear portion 324 is connected to the first pole ear portion 322 , and the third pole ear portion 324 is folded on the side of the electrode body 31 close to the current collecting component 22 .

[0114] One end of the third pole lug 324 is connected to the electrode body 31, and the other end is connected to the first pole lug 322. This allows for a connection between the first pole lug 322 and the electrode body 31, allowing current and heat to be transferred more smoothly through the third pole lug 324 to the first pole lug 322. By folding the third pole lug 324 over the side of the electrode body 31 that is closer to the current collecting component 22, the overall structure of the pole lug 321 can be made compact, thereby reducing the volume of the pole lug structure 32 formed by stacking multiple pole lugs 321, thereby reducing the space within the housing 21 occupied by the pole lug structure 32.

[0115] In the above technical solution, by connecting one end of the third pole ear portion 324 to the electrode body 31 and the other end to the first pole ear portion 322, the connection between the first pole ear portion 322 and the electrode body 31 can be achieved, so that the current and heat can be transferred to the first pole ear portion 322 more smoothly through the third pole ear portion 324; and, by folding the third pole ear portion 324 with the side of the electrode body 31 close to the current collecting component 22, the overall structure of the pole ear sheet 321 can be made compact, thereby reducing the volume of the pole ear structure 32 formed by stacking multiple pole ear sheets 321, thereby reducing the space occupied by the pole ear structure 32 in the shell 21.

[0116] In some embodiments, reference Figure 5-Figure 9 The first pole ear portion 322 is bent relative to the third pole ear portion 324 and has a second pole ear portion 323 . In the same pole ear sheet 321 , the second pole ear portion 323 is folded on a side of the third pole ear portion 324 close to the current collecting component 22 .

[0117] The first pole ear portion 322 is bent relative to the third pole ear portion 324 in a curved shape, and has a second pole ear portion 323. In the same pole ear piece 321, the second pole ear portion 323 is folded on the side of the third pole ear portion 324 close to the current collecting component 22. While achieving heat and current transfer between the third pole ear portion 324 and the second pole ear portion 323, the space occupied by the pole ear piece 321 can be reduced, and the volume of the pole ear structure 32 formed by stacking multiple pole ear pieces 321 can be reduced, thereby reducing the space occupied by the pole ear structure 32 in the shell 21.

[0118] In the above technical solution, the first pole ear portion 322 is bent relative to the third pole ear portion 324 into a curved shape, and the second pole ear portion 323 is provided. In the same pole ear sheet 321, the second pole ear portion 323 is folded on the side of the third pole ear portion 324 close to the current collecting component 22. While achieving heat and current transfer between the third pole ear portion 324 and the second pole ear portion 323, the space occupied by the pole ear sheet 321 can be reduced, and the volume of the pole ear structure 32 formed by stacking multiple pole ear sheets 321 can be reduced, thereby reducing the space occupied by the pole ear structure 32 in the shell 21.

[0119] In some embodiments, reference Figure 10-13 There is a first fold 325 extending along the second direction between the first pole ear portion 322 and the third pole ear portion 324. The first fold 325 is located on one side or the middle of the electrode body 31 along the third direction. The electrode body 31 and the pole ear structure 32 are arranged along the first direction, and the two pole ear structures 32 are arranged along the second direction. The third direction, the second direction and the first direction intersect with each other.

[0120] The first fold 325 is located on one side or the middle of the electrode body 31 along the third direction. The electrode body 31 and the pole ear structure 32 are arranged along the first direction, and the two pole ear structures 32 are arranged along the second direction. The space along the first direction, the second direction and the third direction can be fully utilized to make the overall structure of the pole ear structure 32 and the electrode body 31 compact, reduce the space occupied by the pole ear structure 32, and improve the space utilization rate inside the shell 21; and the first fold 325 extending along the second direction can provide more precise positioning and guiding for the folding of the pole ear sheet 321. For example, during the production process, the operator can fold the first pole ear portion 322 and the third pole ear portion 324 along the first fold 325, so that the folded multiple pole ear sheets 321 can be arranged more regularly in the preset position.

[0121] In the above technical solution, the first fold 325 is located on one side or the middle of the electrode body 31 along the third direction, the electrode body 31 and the pole ear structure 32 are arranged along the first direction, and the two pole ear structures 32 are arranged along the second direction. The space along the first direction, the second direction and the third direction can be fully utilized to make the overall structure of the pole ear structure 32 and the electrode body 31 compact, reduce the space occupied by the pole ear structure 32, and improve the space utilization rate inside the shell 21; and the first fold 325 extending along the second direction can provide more precise positioning and guiding for the folding of the pole ear sheet 321. For example, during the production process, the operator can fold the first pole ear portion 322 and the third pole ear portion 324 along the first fold 325, so that the folded multiple pole ear sheets 321 can be arranged more regularly in the preset position.

[0122] In some embodiments, reference Figure 3-Figure 6 The electrode assembly 3 includes multiple layers of pole pieces, each of which includes a pole piece body for constituting an electrode body 31 , and each layer of pole pieces has a pole tab 321 .

[0123] Since each layer of electrode pieces has an electrode tab 321, each layer of electrode pieces can have a heat conduction channel for outward heat transfer, which can increase the heat dissipation area and flow area of ​​the electrode body 31 to the electrode terminal 23, thereby improving the heat dissipation efficiency and flow efficiency of the electrode body 31 through the electrode tab 321 to the outside, effectively reducing the temperature rise inside the electrode body 31, and thus helping to extend the service life and reliability of the electrode body 31.

[0124] In the above technical solution, since each layer of the electrode pieces has a pole ear piece 321, each layer of the electrode pieces can have a heat dissipation channel for outward heat transfer, which can increase the heat dissipation area and flow area of ​​the electrode body 31 to the electrode terminal 23, thereby improving the heat dissipation efficiency and flow efficiency of the electrode body 31 through the pole ear piece 321 to the outside, effectively reducing the temperature rise inside the electrode body 31, which is beneficial to extending the service life and reliability of the electrode body 31.

[0125] In some embodiments, reference Figure 3-Figure 6 The electrode assembly 3 includes a multi-layer electrode sheet, and the electrode sheet includes an electrode body for constituting an electrode body 31 , and some of the electrode sheets have electrode tabs 321 .

[0126] By having only some of the pole pieces with pole tabs 321, the volume of the pole tab structure 32 formed by stacking multiple pole tabs 321 can be reduced while achieving outward heat dissipation and electrical connection of the electrode body 31, thereby reducing the space inside the shell 21 occupied by the pole tab structure 32, which is beneficial to improving the energy density of the battery cell 20.

[0127] In the above technical solution, only some of the pole pieces have pole tabs 321. In this way, while achieving outward heat dissipation and electrical connection of the electrode body 31, the volume of the pole tab structure 32 formed by stacking multiple pole tabs 321 can be reduced, thereby reducing the space occupied by the pole tab structure 32 in the shell 21, which is beneficial to improving the energy density of the battery cell 20.

[0128] In some embodiments, reference Figure 3-Figure 6 Among the pole pieces of the same polarity, the number of pole pieces with the pole tabs 321 accounts for 1 / 2 to 3 / 4.

[0129] For example, the proportion of the number of layers of pole pieces with pole tabs 321 can be 1 / 2, 7 / 12, 2 / 3, 3 / 4, etc. By making the proportion of the number of layers of pole pieces with pole tabs 321 1 / 2~3 / 4, the thermal conductivity area and flow area of ​​the pole tab 321 and the volume of the pole tab structure 32 can be better balanced. In this way, while making the pole tab 321 have better thermal conductivity efficiency and flow efficiency, the volume of the pole tab structure 32 formed by stacking multiple pole tabs 321 can be reduced, thereby reducing the space in the shell 21 occupied by the pole tab structure 32, which is beneficial to improving the energy density of the battery cell 20.

[0130] It should be explained that the ratio of the number of pole pieces with pole tabs 321 refers to the ratio of the total number of pole pieces with pole tabs 321 to the total number of pole pieces.

[0131] In the above technical solution, by making the proportion of the number of layers of the pole pieces with the pole tabs 321 1 / 2~3 / 4, the thermal conductivity area and the flow area of ​​the pole tab 321 and the volume of the pole tab structure 32 can be better balanced. In this way, while making the pole tab 321 have better thermal conductivity efficiency and flow efficiency, the volume of the pole tab structure 32 formed by stacking multiple pole tabs 321 can be reduced, thereby reducing the space occupied by the pole tab structure 32 in the shell 21, which is beneficial to improving the energy density of the battery cell 20.

[0132] In some embodiments, reference Figure 14-15 The pole tab 321 having the second pole tab portion 323 is the second pole tab, and the remaining pole tabs 321 except the second pole tab are all first pole tabs, wherein the pole tab structure 32 and the electrode body 31 are arranged along the first direction, and when the pole tab 321 is in the unfolded state, the first pole tabs in the same pole tab structure 32 have the same height in the first direction and / or the second pole tabs in the same pole tab structure 32 have the same height in the first direction.

[0133] The first pole tabs in the same pole tab structure 32 have the same height in the first direction, so that each first pole tab can carry current more evenly. The consistent height of the first pole tabs can reduce the differences between the current transmission paths, reduce the possibility of overheating or damage of one or several first pole tabs due to current concentration, enhance the stability of the electrical connection, and evenly distribute heat in the pole tab structure 32, reducing local heat accumulation in one or several first pole tabs and improving the heat dissipation efficiency of the battery cell 20.

[0134] Accordingly, the second tabs in the same tab structure 32 have the same height in the first direction, which can also improve the balance of current and heat distribution between the second tabs, and is beneficial to improving the overall performance and reliability of the battery cell 20.

[0135] In addition, the first pole tabs in the same pole tab structure 32 have the same height and / or the second pole tabs in the same pole tab structure 32 have the same height, which can reduce the manufacturing difficulty of the battery cell 20. For example, in the preparation process of the pole tab 321, since the height requirements for the pole tab 321 are consistent, standardized processes and equipment can be used for batch production, thereby improving production efficiency.

[0136] It should be noted that the tabs 321 being in an unfolded state means that the tabs 321 maintain a certain spatial relationship with each other and are not folded or curled. For example, when the tab structure 32 includes multiple layers of tabs 321, the tabs 321 being in an unfolded state means that each layer of tabs 321 is relatively evenly distributed, so that the surface area of ​​the tabs 321 is exposed to the greatest extent possible.

[0137] In the above technical solution, when the pole tab 321 is in the expanded state, by making the first pole tab in the same pole tab structure 32 have the same height in the first direction and / or the second pole tab in the same pole tab structure 32 have the same height in the first direction, the current and heat distribution between the first pole tab in the same pole tab structure 32 and / or the second pole tab in the same pole tab structure 32 can be made more uniform, thereby reducing the possibility of overheating or damage caused by local current concentration or heat accumulation, and improving the balance of the overall current and heat distribution of the pole tab structure 32, which is beneficial to improving the overall performance and reliability of the battery cell 20.

[0138] In some embodiments, reference Figures 8-12 The pole tab 321 having the second pole tab portion 323 is the second pole tab, and the remaining pole tabs 321 except the second pole tab are all first pole tabs, wherein the pole tab structure 32 and the electrode body 31 are arranged along the first direction. When the pole tab 321 is in the unfolded state, the height of the first pole tab in the same pole tab structure 32 in the first direction is different and / or the height of the second pole tab in the same pole tab structure 32 in the first direction is different.

[0139] The different heights of the first tabs in the first direction within the same tab structure 32 can reduce the volume of the tab structure 32 formed by stacking multiple tabs 321, thereby reducing the space occupied by the tab structure 32 within the housing 21, which is beneficial for improving the energy density of the battery cell 20. For example, when stacking multiple tabs 321, the first tabs of different heights can be arranged in staggered layers. This staggered arrangement can more effectively utilize space and reduce the space occupied by the first tabs within the housing 21 after stacking. For example, the taller tabs 321 can be staggered with the lower tabs 321, making the stacked tabs more compact, thereby reducing the volume of the tab structure 32. For another example, the lower first tabs can be stacked first, and then the taller first tabs can be stacked on top of them. This can also reduce the space occupied by the first tabs after stacking, reducing the volume of the tab structure 32 formed by the stacked multiple tabs 321, thereby reducing the space occupied by the tab structure 32 within the housing 21.

[0140] Correspondingly, the heights of the second pole tabs in the same pole tab structure 32 in the first direction are different, which can also reduce the space occupied by the second pole tabs after stacking, reduce the volume of the pole tab structure 32 formed by stacking multiple pole tabs 321, and thus reduce the space occupied by the pole tab structure 32 in the shell 21.

[0141] In the above technical solution, when the pole tab 321 is in the expanded state, the height of the first pole tab in the same pole tab structure 32 in the first direction is different and / or the height of the second pole tab in the same pole tab structure 32 in the first direction is different. This can reduce the space occupied by the first pole tab in the same pole tab structure 32 and / or the second pole tab in the same pole tab structure 32 after stacking, and reduce the volume of the pole tab structure 32 formed by stacking multiple pole tabs 321. This can reduce the space inside the shell 21 occupied by the pole tab structure 32, which is beneficial to improving the energy density of the battery cell 20.

[0142] In some embodiments, reference Figure 7-11 The first pole ear portion 322 has a first weld print area 3221, and the first weld print areas 3221 of adjacent pole ear sheets 321 in the same pole ear structure 32 are welded together. The second pole ear portion 323 has a second weld print area 3231, and the second weld print area 3231 is welded together with the electrode terminal 23 or the second weld print area 3231 is welded together with the electrode terminal 23 through the current collecting component 22.

[0143] The welding connection of the first weld marks 3221 of adjacent tabs 321 in the same tab structure 32 simplifies the connection between the adjacent tabs 321 and provides greater stability. It also forms a continuous current transmission path between the adjacent tabs 321 and enables heat transfer between the adjacent tabs 321, allowing this heat to subsequently be dissipated outward through the tab 321 having the second tab portion 323. Accordingly, the welding connection of the second weld marks 3231 of the second tab portion 323 to the electrode terminal 23 or the current collecting component 22 simplifies the connection between the second tab portion 323 and the electrode terminal 23 or the current collecting component 22 and provides greater stability. It also forms a continuous current transmission path and heat conduction path between the second tab portion 323 and the electrode terminal 23, thereby enabling current transmission and heat transfer between the electrode body 31 and the electrode terminal 23.

[0144] In the above technical solution, by welding the first weld print area 3221 of adjacent pole tabs 321 in the same pole tab structure 32, the second weld print area 3231 of the second pole tab portion 323 is welded to the electrode terminal 23, or the second weld print area 3231 is welded to the electrode terminal 23 through the current collecting component 22. This can make the connection between the adjacent pole tabs 321 and the second pole tab portion 323 and the electrode terminal 23 or the current collecting component 22 simple and have strong stability, and can also form continuous current transmission and heat transfer between the adjacent pole tabs 321 and the second pole tab portion 323 and the electrode terminal 23, thereby realizing the process of current transmission and heat transfer between the electrode body 31 and the electrode terminal 23.

[0145] In some embodiments, reference Figure 7-11The stacking thickness of all first pole ear portions 322 in the same pole ear structure 32 is T1, and the stacking thickness of all second pole ear portions 323 in the same pole ear structure 32 is T2. When the pole ear sheet 321 is in the unfolded state, the size of the first weld print area 3221 in the second direction is c, the size of the first weld print area 3221 in the first direction is d, the size of the second weld print area 3231 in the second direction is a, and the size of the second weld print area 3231 in the first direction is b. a, b, c, d, T1, and T2 satisfy: (a*b) / (c*d)=(T1 / T2)*k, where k ranges from 1.0 to 1.5. The electrode body 31 and the pole ear structure 32 are arranged along the first direction, and the two pole ear structures 32 are arranged along the second direction, and the second direction intersects with the first direction.

[0146] The relationship between the dimension a of the second weld print area 3231 in the second direction, the dimension b of the second weld print area 3231 in the first direction, the dimension c of the first weld print area 3221 in the second direction, the dimension d of the first weld print area 3221 in the first direction, the stacking thickness T1 of all first pole lug portions 322 in the same pole lug structure 32, and the stacking thickness T2 of all second pole lug portions 323 in the same pole lug structure 32 satisfies (a*b) / (c*d)=(T1 / T2)*k. For example, the value of k can be 1.0, 1.1, 1.2, 1.3, or 1.5. By setting k in the range of 1.0 to 1.5, the area of ​​the second weld print area 3231 can be made larger, so that the heat conduction area and the flow area of ​​the second pole ear portion 323 can be made larger, so that the pole ear piece 321 can have better flow efficiency and heat conduction efficiency; and the stacking thickness of all the first pole ear portions 322 in the same pole ear structure 32 and the stacking thickness of all the second pole ear portions 323 in the same pole ear structure 32 can be made smaller, so that the volume of the pole ear structure 32 formed by stacking multiple pole ear pieces 321 can be reduced, thereby reducing the space inside the shell 21 occupied by the pole ear structure 32.

[0147] In the above technical solution, the relationship between the dimension a of the second weld mark area 3231 in the second direction, the dimension b of the second weld mark area 3231 in the first direction, the dimension c of the first weld mark area 3221 in the second direction, the dimension d of the first weld mark area 3221 in the first direction, the stacking thickness T1 of all first pole lug portions 322 in the same pole lug structure 32, and the stacking thickness T2 of all second pole lug portions 323 in the same pole lug structure 32 satisfies (a*b) / (c*d)=(T1 / T2)*k, where k is in the range of 1.0 to 1.5. This can effectively balance the flow efficiency and thermal efficiency of the pole lug 321 and the volume of the stacked multiple pole lugs 321 in the same pole lug structure 32. This makes the area of ​​the second weld mark area 3231 larger, so that the pole lug 321 has better flow efficiency and thermal efficiency. At the same time, this can reduce the volume of the pole lug structure 32 formed by the stacked multiple pole lugs 321, thereby reducing the space occupied by the pole lug structure 32 in the housing 21.

[0148] In some embodiments, reference Figure 7-11 When the tab sheet 321 is in the unfolded state, the size of the first weld print area 3221 in the second direction is c, and the size of the first weld print area 3221 in the first direction is d, c and d satisfy: c / d>3, the electrode body 31 and the tab structure 32 are arranged along the first direction, and the two tab structures 32 are arranged along the second direction, and the second direction intersects with the first direction.

[0149] For example, the ratio of the dimension c of the first weld print area 3221 in the second direction to the dimension d of the first weld print area 3221 in the first direction can be: c / d=3.5, c / d=4, c / d=5, c / d=6, c / d=8, etc., by satisfying the dimension c of the first weld print area 3221 in the second direction and the dimension d of the first weld print area 3221 in the first direction c / d>3, when the pole tab 321 is in the unfolded state, the first weld print area 3221 can be made into a slender shape. Since the first pole ear portion 322 is bent relative to the second pole ear portion 323, the bent first pole ear portion 322 has a certain bending force, and the slender first weld print area 32 21 can better adapt to this bending structure, reduce the possibility of local stress concentration in the first weld mark area 3221, and further reduce the possibility of the first pole ear portion 322 being broken due to this part of the bending force, especially the possibility of the first weld mark area 3221 being broken due to the concentrated bending force, which is beneficial to extending the service life of the pole ear piece 321. In addition, the dimension d of the first weld mark area 3221 in the first direction is small. Accordingly, when the first pole ear portion 322 is bent, the dimension of the first weld mark area 3221 in the first direction can be reduced, and further reduce the space in the shell 21 occupied by the first pole ear piece in the first direction after being folded, which is beneficial to improving the energy density of the battery cell 20.

[0150] In the above technical solution, the dimension c of the first weld print area 3221 in the second direction and the dimension d of the first weld print area 3221 in the first direction satisfy c / d>3. When the pole tab 321 is in the unfolded state, the first weld print area 3221 can be made slender. Since the first pole ear portion 322 is bent relative to the second pole ear portion 323, the bent first pole ear portion 322 has a certain bending force. The slender first weld print area 3221 can better adapt to this bending structure, reducing the possibility of local stress concentration in the first weld print area 3221. The bending force can reduce the possibility of the first pole ear 322 being broken due to this part of the bending force, especially the possibility of the first weld mark area 3221 being broken due to the concentrated bending force, which is beneficial to extending the service life of the pole ear 321. In addition, the dimension d of the first weld mark area 3221 in the first direction is small. Accordingly, when the first pole ear 322 is bent, the dimension of the first weld mark area 3221 in the first direction can be reduced, thereby reducing the space in the shell 21 occupied by the first pole ear in the first direction after the folding of the first pole ear, which is beneficial to improving the energy density of the battery cell 20.

[0151] In some embodiments, reference Figure 7-11 , c and d satisfy: c / d =6~8.

[0152] For example, the ratio of the size c of the first weld print area 3221 in the second direction to the size d of the first weld print area 3221 in the first direction can be: c / d=6, c / d=6.5, c / d=7, c / d=7.5, c / d=8, etc. By satisfying the size c of the first weld print area 3221 in the second direction and the size d of the first weld print area 3221 in the first direction c / d=6~8, the size c of the first weld print area 3221 in the second direction is larger and the size d of the first weld print area 3221 in the first direction is smaller, which can better The area and shape of the first weld print area 3221 are balanced so that the area of ​​the first weld print area 3221 is larger, so that the heat conduction and flow area of ​​the first weld print area 3221 are larger, thereby making the first pole ear portion 322 have better flow efficiency and thermal conductivity efficiency. The first weld print area 3221 can also be made slender. In this way, when the first pole ear portion 322 is in a bent shape, the possibility of the first pole ear portion 322 being broken due to concentrated bending force can be effectively reduced, thereby making the connection between adjacent pole ear sheets 321 more stable.

[0153] In the above technical solution, by satisfying c / d=6-8 between the dimension c of the first weld print area 3221 in the second direction and the dimension d of the first weld print area 3221 in the first direction, the area and shape of the first weld print area 3221 can be well balanced, so that the area of ​​the first weld print area 3221 is larger, so that the heat conduction and flow area of ​​the first weld print area 3221 are larger, thereby making the first pole lug portion 322 have better flow efficiency and thermal conductivity efficiency. The first weld print area 3221 can also be made slender. In this way, when the first pole lug portion 322 is in a bent shape, the possibility of the first pole lug portion 322 being broken due to concentrated bending force can be effectively reduced, thereby making the connection between adjacent pole lugs 321 more stable.

[0154] In some embodiments, reference Figure 7-11 The side of the second pole ear portion 323 away from the first pole ear portion 322 is the first side 3232, the distance between the second weld print area 3231 and the first side 3232 is L2, a second fold 326 extending along the second direction is provided between the first pole ear portion 322 and the second pole ear portion 323, the distance between the second weld print area 3231 and the second fold 326 is L3, the second pole ear portion 323 has a second side 3233 arranged opposite to each other along the second direction, the distance between the second weld print area 3231 and the second side 3233 is L1, at least one of L1, L2 and L3 is greater than 0.5 mm, the electrode body 31 and the pole ear structure 32 are arranged along the first direction, the two pole ear structures 32 are arranged along the second direction, and the second direction intersects with the first direction.

[0155] For example, the value of at least one of L1, L2, and L3 can be 0.6 mm, 0.8 mm, 1.0 mm, 1.5 mm, 2.0 mm, etc. By making at least one of the distance L1 between the second weld print area 3231 and the second side 3233, the distance L2 between the second weld print area 3231 and the first side 3232, and the distance L3 between the second weld print area 3231 and the second fold 326 greater than 0.5 mm, the distance between the second weld print area 3231 and the first side 3232 or the second side 3233 or the second fold 326 of the second pole ear portion 323 can be made larger. During the assembly process, the distance between the second weld print area 3231 and the side of the second pole ear portion 323 can provide a certain operating space for the operator to facilitate the press-fitting operation of the second pole ear sheet and can reduce deformation or damage of the second weld print area 3231. For example, when the second tab is press-fitted, this spacing can reduce the possibility of deformation or damage of the second weld print area 3231 due to compression, thereby making the electrical connection at the second weld print area 3231 more reliable.

[0156] In the above technical solution, at least one of the distance L1 between the second weld print area 3231 and the second side 3233, the distance L2 between the second weld print area 3231 and the first side 3232, and the distance L3 between the second weld print area 3231 and the second fold 326 is greater than 0.5 mm. This can make the distance between the second weld print area 3231 and the first side 3232 or the second side 3233 or the second fold 326 of the second pole ear portion 323 larger. During the press-fitting process, the distance between the second weld print area 3231 and the side of the second pole ear portion 323 can provide a certain operating space for the operator, so as to facilitate the press-fitting operation of the second pole tab sheet and reduce the possibility of deformation or damage of the second weld print area 3231.

[0157] In some embodiments, reference Figure 7-11 , at least one of L1, L2, and L3 has a value range of 1.0~3.0mm.

[0158] For example, the value of at least one of L1, L2, and L3 can be 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, etc. By setting the value range of at least one of L1, L2, and L3 to 1.0~3.0 mm, the distance between the second weld print area 3231 and the side of the second pole ear portion 323 and the area of ​​the second pole ear portion 323 when in the expanded state can be better balanced. While making the distance between the second weld print area 3231 and the side of the second pole ear portion 323 larger to facilitate the press-fitting operation of the second pole ear portion 323, the area of ​​the second pole ear portion 323 can be made smaller, which is beneficial to reducing the weight of the pole ear structure 32 and reducing manufacturing costs.

[0159] In the above technical solution, by having at least one of L1, L2, and L3 have a value range of 1.0~3.0mm, the area of ​​the second pole ear portion 323 and the area of ​​the second weld print area 3231 can be better balanced. While making the area of ​​the second weld print area 3231 larger so that the second pole ear sheet has better flow efficiency and thermal conductivity, the area of ​​the second pole ear portion 323 can be made smaller, which is beneficial to reducing the weight of the pole ear structure 32 and reducing manufacturing costs.

[0160] In some embodiments, reference Figure 7-11A second fold 326 extending along the second direction is defined between the first electrode tab 322 and the second electrode tab 323. The spacing between the first weld mark 3221 and the second fold 326 is L5. The electrode tab 321 has a first fold 325 extending along the second direction. The first fold 325 is located between the first electrode tab 322 and the electrode body 31. The spacing between the first weld mark 3221 and the first fold 325 is L6. The first electrode tab 322 has a third side 3222 oppositely disposed along the second direction. The spacing between the first weld mark 3221 and the third side 3222 is L4. At least one of L4, L5, and L6 is greater than 0.5 mm.

[0161] For example, the value of at least one of L4, L5, and L6 can be 0.6 mm, 0.8 mm, 1.0 mm, 1.5 mm, 2.0 mm, etc. By making at least one of the distance L4 between the first weld print area 3221 and the third side 3222, the distance L5 between the first weld print area 3221 and the second fold 326, and the distance L6 between the first weld print area 3221 and the first fold 325 greater than 0.5 mm, the distance between the first weld print area 3221 and the third side 3222 or the first fold 325 or the second fold 326 of the first electrode tab portion 322 can be made larger. During the assembly process, this part of the distance between the first weld print area 3221 and the third side 3222 or the first fold 325 or the second fold 326 can provide a certain operating space for the operator to facilitate the press-fitting operation of the first electrode tab sheet and can reduce the possibility of deformation or damage of the first weld print area 3221. For example, when the second tab is press-fitted, this spacing can reduce deformation or damage of the first weld print area 3221 due to compression, thereby making the electrical connection at the first weld print area 3221 more reliable.

[0162] In the above technical solution, by making at least one of the distance L4 between the first weld mark area 3221 and the third side 3222, the distance L5 between the first weld mark area 3221 and the second fold 326, and the distance L6 between the first weld mark area 3221 and the first fold 325 greater than 0.5 mm, the distance between the first weld mark area 3221 and the third side 3222 or the first fold 325 or the second fold 326 of the first electrode tab portion 322 can be made larger. During the press-fitting process, this distance between the first weld mark area 3221 and the third side 3222 or the first fold 325 or the second fold 326 can provide a certain operating space for the operator, thereby facilitating the press-fitting operation of the first electrode tab sheet and reducing the possibility of deformation or damage of the first weld mark area 3221.

[0163] In some embodiments, reference Figure 7-11, at least one of L4, L5, and L6 has a value range of 1.0~3.0mm.

[0164] For example, the value of at least one of L4, L5, and L6 can be 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, etc. By setting the value range of at least one of L4, L5, and L6 to 1.0~3.0 mm, and by setting the value range of at least one of L4, L5, and L6 to 1.0~3.0 mm, the distance between the first weld print area 3221 and the side of the first pole ear portion 322 and the area of ​​the first pole ear portion 322 when in the unfolded state can be better balanced. While making the distance between the first weld print area 3221 and the side of the first pole ear portion 322 larger to facilitate the press-fitting operation of the first pole ear portion 322, the area of ​​the first pole ear portion 322 can be made smaller, which is beneficial to reducing the weight of the pole ear structure 32 and reducing manufacturing costs.

[0165] In the above technical solution, by having at least one of L4, L5, and L6 have a value range of 1.0 to 3.0 mm, the distance between the first weld mark area 3221 and the side of the first pole ear portion 322 and the area of ​​the first pole ear portion 322 when in the unfolded state can be better balanced. While making the distance between the first weld mark area 3221 and the side of the first pole ear portion 322 larger to facilitate the press-fitting operation of the first pole ear portion 322, the area of ​​the first pole ear portion 322 can be made smaller, which is beneficial to reducing the weight of the pole ear structure 32 and reducing manufacturing costs.

[0166] In some embodiments, a current collecting component 22 is included, and the current collecting component 22 is disposed in the housing 21 . The second electrode ear portion 323 is connected to the electrode terminal 23 through the current collecting component 22 .

[0167] The shell 21 can support and protect the electrode assembly 3 and the current collecting component 22, reduce the wear of the current collecting component 22 caused by external impact, and help extend the overall service life of the battery cell 20. The second pole ear 323 is connected to the electrode terminal 23 through the current collecting component 22, and heat transfer and electrical connection between the second pole ear 323 and the electrode terminal 23 through the current collecting component 22 can be achieved, thereby achieving electrical connection between the electrode body 31 and the electrode terminal 23, and heat dissipation of the electrode body 31 to the outside of the shell 21 through the electrode terminal 23.

[0168] In the above technical solution, the shell 21 can support and protect the electrode assembly 3 and the current collecting component 22, reduce the wear of the current collecting component 22 caused by external impact, and help to extend the overall service life of the battery cell 20. The second pole ear 323 is connected to the electrode terminal 23 through the current collecting component 22, and the heat transfer and electrical connection between the second pole ear 323 and the electrode terminal 23 through the current collecting component 22 can be achieved, thereby achieving electrical connection between the electrode body 31 and the electrode terminal 23, and also achieving heat dissipation of the electrode body 31 to the outside of the shell 21 through the electrode terminal 23.

[0169] Refer to the following Figures 1-15 A battery cell 20 according to some embodiments of the present invention is described.

[0170] Reference Figures 1-6 In this embodiment, the battery cell 20 includes a housing 21 , a current collecting component 22 and an electrode assembly 3 .

[0171] The housing 21 is provided with an electrode terminal 23. The current collecting component 22 is disposed within the housing 21 and connected to the electrode terminal 23. The electrode assembly 3 is housed within the housing 21 and includes an electrode body 31 and a tab structure 32. Each tab structure 32 is connected to the electrode body 31 and includes a plurality of stacked tabs 321. Each tab 321 includes a first tab portion 322 connected to the electrode body 31. The first tab portions 322 of adjacent tabs 321 in the same tab structure 32 are connected. Some tabs 321 in each tab structure 32 also include a second tab portion 323 connected to the first tab portion 322. The second tab portion 323 is connected to the electrode terminal 23 via the current collecting component 22.

[0172] The electrode assembly 3 includes multiple layers of electrode sheets, each of which includes an electrode body 31. Each layer of electrode sheets has a tab 321. Alternatively, some electrode sheets have tabs 321, and among electrode sheets of the same polarity, the number of layers of electrode sheets having tabs 321 accounts for 1 / 2 to 3 / 4.

[0173] The tab 321 having the second tab portion 323 is a second tab, and the remaining tabs 321 excluding the second tab are first tabs. The tab structure 32 and the electrode body 31 are arranged along a first direction. When the tabs 321 are in an unfolded state, the first tabs in the same tab structure 32 have the same height in the first direction, and / or the second tabs in the same tab structure 32 have the same height in the first direction. Alternatively, the tab structure 32 and the electrode body 31 are arranged along the first direction. When the tabs 321 are in an unfolded state, the first tabs in the same tab structure 32 have different heights in the first direction, and / or the second tabs in the same tab structure 32 have different heights in the first direction.

[0174] When the tabs 321 are in the unfolded state, the second tab portion 323 is located on the side of the first tab portion 322 away from the electrode body 31. Each tab 321 includes a third tab portion 324. One end of the third tab portion 324 is connected to the electrode body 31, and the other end of the third tab portion 324 is connected to the first tab portion 322. The third tab portion 324 is folded over the side of the electrode body 31 near the electrode terminal 23. The first tab portion 322 is bent relative to the third tab portion 324 in a curved shape. Within the same tab 321, the second tab portion 323 is folded over the side of the third tab portion 324 near the electrode terminal 23.

[0175] There is a first fold 325 extending along the second direction between the first pole ear portion 322 and the third pole ear portion 324. The first fold 325 is located on one side or the middle of the electrode body 31 along the third direction. The electrode body 31 and the pole ear structure 32 are arranged along the first direction, and the two pole ear structures 32 are arranged along the second direction. The third direction, the second direction and the first direction intersect with each other.

[0176] The first pole lug portion 322 has a first weld print area 3221 , and the first weld print areas 3221 of adjacent pole lug sheets 321 in the same pole lug structure 32 are welded together. The second pole lug portion 323 has a second weld print area 3231 , and the second weld print area 3231 is welded together with the electrode terminal 23 through the current collecting component 22 . The stacking thickness of all first pole ear portions 322 in the same pole ear structure 32 is T1, and the stacking thickness of all second pole ear portions 323 in the same pole ear structure 32 is T2. When the pole ear sheet 321 is in the unfolded state, the size of the first weld print area 3221 in the second direction is c, the size of the first weld print area 3221 in the first direction is d, the size of the second weld print area 3231 in the second direction is a, and the size of the second weld print area 3231 in the first direction is b. a, b, c, d, T1, and T2 satisfy: (a*b) / (c*d)=(T1 / T2)*k, where k ranges from 1.0 to 1.5. The electrode body 31 and the pole ear structure 32 are arranged along the first direction, and the two pole ear structures 32 are arranged along the second direction, and the second direction intersects with the first direction.

[0177] When the tab 321 is in the unfolded state, the dimension of the first weld print area 3221 in the second direction is c, and the dimension of the first weld print area 3221 in the first direction is d, and c and d satisfy: c / d=6-8.

[0178] The side of the second pole ear portion 323 away from the first pole ear portion 322 is the first side 3232, the distance between the second weld print area 3231 and the first side 3232 is L2, a second fold 326 extending along the second direction is provided between the first pole ear portion 322 and the second pole ear portion 323, the distance between the second weld print area 3231 and the second fold 326 is L3, the second pole ear portion 323 has a second side 3233 arranged opposite to each other along the second direction, the distance between the second weld print area 3231 and the second side 3233 is L1, and the value range of at least one of L1, L2, and L3 is 1.0-3.0 mm.

[0179] A second fold 326 extending along the second direction is provided between the first pole ear portion 322 and the second pole ear portion 323. The spacing between the first weld print area 3221 and the second fold 326 is L5. The pole ear sheet 321 has a first fold 325 extending along the second direction. The first fold 325 is located between the first pole ear portion 322 and the electrode body 31. The spacing between the first weld print area 3221 and the first fold 325 is L6. The first pole ear portion 322 has a third side edge 3222 arranged opposite to each other along the second direction. The spacing between the first weld print area 3221 and the third side edge 3222 is L4. The value range of at least one of L4, L5, and L6 is 1.0-3.0 mm.

[0180] In the above-mentioned battery cell 20, the pole ear structure 32 includes a plurality of pole ear sheets 321 stacked together, so that the heat conduction area and the flow area of ​​the pole ear structure 32 can be made larger, so as to improve the heat conduction efficiency and the flow efficiency of the electrode body 31, thereby effectively reducing the temperature rise inside the electrode body 31, thereby improving the service life and reliability of the electrode body 31; and, since only some of the pole ear sheets 321 have the second pole ear portion 323 connected to the electrode terminal 23, while achieving outward heat dissipation and electrical connection of the electrode body 31, the volume of the pole ear structure 32 formed by the plurality of pole ear sheets 321 can be reduced, thereby reducing the space inside the shell 21 occupied by the pole ear structure 32, which is beneficial to improving the energy density of the battery cell 20.

[0181] Secondly, refer to Figure 16 The present invention provides a battery device 100 , including a box body 10 and a battery cell 20 according to the first embodiment of the present invention. The battery cell 20 is disposed in the box body 10 .

[0182] In the above technical solution, by providing the above battery cells 20 , the battery device 100 can have higher reliability and better performance.

[0183] Thirdly, refer to Figure 16 and Figure 17The present invention provides an electrical device 1000 , comprising the battery device 100 according to the second embodiment of the present invention.

[0184] The power-consuming device 1000 may be a vehicle, and the battery device 100 may be installed at the bottom of the vehicle body 200 .

[0185] In the above technical solution, by providing the above battery device 100 , the electrical device 1000 can have higher reliability and better performance.

[0186] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative use of the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0187] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and purpose of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A battery cell, characterized in that: include: a housing, wherein the housing is provided with electrode terminals; an electrode assembly housed in the housing and comprising an electrode body and a tab structure, each tab structure being connected to the electrode body and comprising a plurality of tab sheets stacked together; Wherein, each of the pole tabs includes a first pole tab portion, and the first pole tab portions of adjacent pole tabs in the same pole tab structure are connected. Some of the pole tabs in each pole tab structure also include a second pole tab portion connected to the first pole tab portion, and the second pole tab portion is connected to the electrode terminal. When the pole tab is in an expanded state, the second pole tab portion is located on the side of the first pole tab portion away from the electrode body.

2. The battery cell according to claim 1, wherein: Each of the electrode tabs includes a third electrode portion, one end of the third electrode portion is connected to the electrode body, the other end of the third electrode portion is connected to the first electrode portion, and the third electrode portion is folded on a side of the electrode body close to the electrode terminal.

3. The battery cell according to claim 2, characterized in that: The first electrode tab portion is bent relative to the third electrode tab portion in a curved shape, and has the second electrode tab portion. In the same electrode tab sheet, the second electrode tab portion is folded on a side of the third electrode tab portion close to the electrode terminal.

4. The battery cell according to claim 2, characterized in that: There is a first fold extending along the second direction between the first pole ear portion and the third pole ear portion, and the first fold is located on one side or the middle of the electrode body along the third direction. The electrode body and the pole ear structure are arranged along the first direction, and the two pole ear structures are arranged along the second direction. The third direction, the second direction and the first direction intersect each other.

5. The battery cell according to claim 1, characterized in that The electrode assembly includes multiple layers of pole pieces, each of which includes a pole piece body for constituting the electrode body, and each layer of the pole pieces has the pole tab.

6. The battery cell according to claim 1, characterized in that The electrode assembly includes a plurality of layers of pole pieces, each of which includes a pole piece body for constituting the electrode body, and a portion of the pole pieces has the pole tabs.

7. The battery cell according to claim 6, characterized in that Among the pole pieces of the same polarity, the proportion of the pole pieces with the pole tabs is 1 / 2 to 3 / 4.

8. The battery cell according to claim 1, wherein: The pole tab having the second pole tab portion is the second pole tab, and the remaining pole tabs except the second pole tab are the first pole tabs; In which, the tab structure and the electrode body are arranged along a first direction. When the tab pieces are in an unfolded state, the heights of the first tab pieces in the same tab structure in the first direction are the same and / or the heights of the second tab pieces in the same tab structure in the first direction are the same.

9. The battery cell according to claim 1, characterized in that The pole tab having the second pole tab portion is the second pole tab, and the remaining pole tabs except the second pole tab are the first pole tabs; In which, the tab structure and the electrode body are arranged along a first direction. When the tab pieces are in an expanded state, the heights of the first tab pieces in the same tab structure in the first direction are different and / or the heights of the second tab pieces in the same tab structure in the first direction are different.

10. The battery cell according to claim 1, characterized in that The first pole ear portion has a first weld print area, and the first weld print areas of adjacent pole ear sheets in the same pole ear structure are welded and connected. The second pole ear portion has a second weld print area, and the second weld print area is welded and connected to the electrode terminal or the second weld print area is welded and connected to the electrode terminal through a current collecting component.

11. The battery cell according to claim 10, characterized in that The stacking thickness of all the first pole ear portions in the same pole ear structure is T1, and the stacking thickness of all the second pole ear portions in the same pole ear structure is T2. When the pole ear sheet is in the unfolded state, the size of the first weld print area in the second direction is c, the size of the first weld print area in the first direction is d, the size of the second weld print area in the second direction is a, and the size of the second weld print area in the first direction is b. a, b, c, d, T1, and T2 satisfy: (a*b) / (c*d)=(T1 / T2)*k, where k is in the range of 1.0~1.

5. The electrode body and the pole ear structure are arranged along the first direction, and the two pole ear structures are arranged along the second direction, and the second direction intersects with the first direction.

12. The battery cell according to claim 10, characterized in that When the tab sheet is in the unfolded state, the size of the first weld print area in the second direction is c, and the size of the first weld print area in the first direction is d, c and d satisfy: c / d>3, the electrode body and the tab structure are arranged along the first direction, the two tab structures are arranged along the second direction, and the second direction intersects with the first direction.

13. The battery cell according to claim 12, characterized in that: c and d satisfy: c / d = 6~8.

14. The battery cell according to claim 10, characterized in that The side of the second pole ear portion away from the first pole ear portion is the first side edge, the distance between the second weld print area and the first side edge is L2, a second fold extending along the second direction is provided between the first pole ear portion and the second pole ear portion, the distance between the second weld print area and the second fold is L3, the second pole ear portion has a second side edge arranged opposite to each other along the second direction, the distance between the second weld print area and the second side edge is L1, at least one of L1, L2 and L3 is greater than 0.5 mm, the electrode body and the pole ear structure are arranged along the first direction, the two pole ear structures are arranged along the second direction, and the second direction intersects with the first direction.

15. The battery cell according to claim 14, characterized in that The value range of at least one of L1, L2, and L3 is 1.0-3.0 mm.

16. The battery cell according to claim 10, characterized in that A second fold extending along the second direction is provided between the first pole ear portion and the second pole ear portion, and a distance between the first weld print area and the second fold is L5. The pole ear sheet has a first fold extending along the second direction, and the first fold is located between the first pole ear portion and the electrode body, and a distance between the first weld print area and the first fold is L6. The first pole ear portion has a third side edge arranged opposite to each other along the second direction, and a distance between the first weld print area and the third side edge is L4. At least one of L4, L5, and L6 is greater than 0.5 mm.

17. The battery cell according to claim 14, characterized in that The value range of at least one of L4, L5, and L6 is 1.0 to 3.0 mm.

18. The battery cell according to any one of claims 1 to 17, characterized in that: include: A current collecting component is provided in the housing, and the second electrode tab is connected to the electrode terminal via the current collecting component.

19. A battery device, characterized in that: include: Box; The battery cell according to any one of claims 1-18, wherein the battery cell is arranged in the box.

20. An electrical device, characterized in that: A battery device comprising the battery device of claim 19.

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