Battery cell, battery device, and electric device

Abstract

The application discloses a battery monomer, a battery device and a power utilization device, and belongs to the battery field. The battery monomer comprises an end cover, a first electrode terminal, a plurality of electrode assemblies, a main body part and a first tab, the first tab comprises a plurality of sub tabs, each sub tab of each first tab is connected to one end of a first tab segment close to the end cover, at least part of the sub tabs are bent in a first direction to form a first tab part on the same side, and parts of adjacent sub tabs in the first tab part are stacked in the thickness direction of the end cover. A first current collecting member is connected to one first current collecting member and the first current collecting member is connected to the plurality of electrode assemblies, or the first electrode terminal is connected to two first current collecting members, and each first current collecting member is connected to at least one electrode assembly. The technical scheme of the embodiment of the application reduces the height of the sub tab, reduces the risk of folding of the first tab, reduces the probability of increasing the current transmission resistance caused by the cracking of the first tab, and improves the performance of the battery monomer.

Description

Technical Field

[0001] This application relates to the field of batteries, specifically to a battery cell, a battery device, and an electrical device. Background Technology

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry, and electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of this sustainable development. For electric vehicles, battery technology is a crucial factor in their development.

[0003] In a battery cell with multiple electrode components, when connecting the tabs to the terminals, the multiple sub-tabs of the tabs need to be gathered together before connecting them to the terminals. As the electrode components become thicker, the gathered tabs can become too long, making them prone to folding during manufacturing and affecting the performance of the battery cell. Utility Model Content

[0004] In view of the above problems, this application provides a battery cell, a battery, and an electrical device that can alleviate the problem of the tabs being easily folded.

[0005] In a first aspect, this application provides a battery cell, comprising: an end cap; a first electrode terminal disposed on the end cap; a plurality of electrode assemblies, each electrode assembly including a main body and a first electrode tab, the main body including a plurality of first electrode segments stacked along a first direction and having the same polarity, the first electrode tab including a plurality of sub-electrode tabs, each of the sub-electrode tabs of each first electrode tab being connected to one end of a first electrode segment near the end cap, at least a portion of the sub-electrode tabs being bent toward the same side along the first direction to form a first electrode tab portion, portions of adjacent sub-electrode tabs in the first electrode tab portion being stacked along the thickness direction of the end cap, the first direction being perpendicular to the thickness direction of the end cap; and a first current collector, comprising sequentially connected... The device comprises a first connecting segment, a bending segment, and a second connecting segment. The first connecting segment is stacked and connected to the first electrode lug along the thickness direction of the end cap. The second connecting segment is located on the side of the first connecting segment near the end cap and is connected to the first electrode terminal. The second connecting segment and the first connecting segment are connected through the bending segment, and the first connecting segment and the second connecting segment are located on the same side of the bending segment in the first direction. The first electrode terminal is connected to one first current collector and the first current collector is connected to multiple electrode assemblies, or the first electrode terminal is connected to two first current collectors and each first current collector is connected to at least one electrode assembly.

[0006] In the technical solution of this application embodiment, by setting at least a portion of the sub-tabs of the first tabs of multiple electrode assemblies in the form of a first tab portion, the height of each sub-tab is shortened. At the same time, a first current collector is provided between the first tab portion and the first electrode terminal, and the first tab and the first electrode terminal are connected through the first current collector, further shortening the height of the sub-tabs. By reducing the height of the sub-tabs, the risk of the first tabs flipping is reduced, the probability of the first tabs cracking leading to an increase in current transmission resistance is reduced, and the performance of the battery cell is improved. In addition, by shortening the height of the sub-tabs, it is also beneficial to increase the height of the main body, thereby increasing the energy density of the battery cell.

[0007] In some embodiments, the first electrode terminal is connected to two first current collectors, and the bent sections of the two first current collectors are arranged opposite to each other.

[0008] In the above technical solution, the bent sections of the two first current collectors are arranged opposite to each other, which makes it easier to connect each first current collector with the corresponding electrode assembly and improves assembly efficiency.

[0009] In some embodiments, the first tab connected to each of the first current collector components is bent toward the side closer to the other first current collector component. In the above technical solution, the first tab of each electrode assembly can be connected to the first connecting segment, which facilitates the assembly and connection of the two and improves the reliability of the connection between the first tab and the first connecting segment.

[0010] In some embodiments, the first tab connected to each of the first current collectors is bent toward the side away from the other first current collector. In the above technical solution, the first tabs of the two electrode assemblies can be bent and smoothed away from the other electrode assembly, which can reduce the probability of interference between the tabs inside the battery cell.

[0011] In some embodiments, the first current collector connects to multiple first tabs of multiple electrode assemblies, the sub-tabs of the multiple first tabs are bent in the same direction, and portions of the first tabs of two adjacent electrode assemblies are stacked along the thickness direction of the end cap. In the above technical solution, each first electrode terminal can connect to multiple electrode assemblies, and the sub-tabs of adjacent electrode assemblies are bent in the same direction and overlapped, thereby facilitating the fit between the tabs and the first current collector, without increasing the height of the sub-tabs of any electrode assembly, and reducing the risk of tab folding.

[0012] In some embodiments, the first electrode tab is welded to the first connecting segment to form at least one first solder mark, and adjacent sub-electrodes in the first electrode tab are fixedly connected only through the first solder mark. In the above technical solution, after the sub-tab is bent in the first direction to form the first tab, and before the first tab and the first connecting section are stacked and welded, the multiple sub-tabs of the first tab are not fixedly connected or pre-welded. This allows the multiple sub-tabs of the first tab to be smoothed and bent before the first tab and the first connecting section are welded and assembled. This enables the multiple sub-tabs to have relative movement and lateral movement during the smoothing and bending process, allowing each sub-tab to adapt to the length change caused by the bending. This reduces the phenomenon of local stress concentration or local bulging of the sub-tabs during the smoothing and bending process, thereby effectively improving the welding quality between the first tab and the first connecting section. It also effectively alleviates the phenomenon of cracking or breakage of the sub-tabs during assembly or use, reducing the risk of unstable connection and connection failure between the first tab and the first connecting section during use, and is conducive to improving the stability and reliability of the battery cell.

[0013] In some embodiments, a plurality of the sub-tabs extend to the side of the first connecting section opposite to the main body to form a second tab, and the second tab is located on one side of the first tab in the first direction and is connected to the first current collector. In the above technical solution, by providing the second tab, a portion of the first tab can extend to the side of the first connecting section opposite to the first tab for connection, which helps to reduce the size of the first current collector in the first direction, reduce the space occupied by the first current collector, and improve the reliability of the connection between the first tab and the first current collector.

[0014] In some embodiments, the second electrode lug and the bent section are located at both ends of the first connecting section in the first direction, wherein a first slot is formed between the second electrode lug and the first electrode lug, and the end of the first connecting section away from the bent section is inserted into the first slot. In the above technical solution, by forming a first slot between the second electrode lug and the first electrode lug, the first connecting section can be inserted and engaged with the first slot, thereby improving the reliability of the connection between the first electrode lug and the first connecting section.

[0015] In some embodiments, the second electrode lug is welded together to form at least one second solder mark. In the above technical solution, by welding multiple sub-electrode lugs of the second electrode lug, the multiple sub-electrode lugs are less likely to fall apart, thereby facilitating the bending of the second electrode lug and its connection with the first current collector, and improving the reliability of the connection between the second electrode lug and the first current collector.

[0016] In some embodiments, the second tab is welded to the first connecting segment to form at least one third solder mark. In the above technical solution, by welding the second tab to the first connecting segment, the reliability of the connection between the first tab and the first connecting segment is improved, thereby enhancing the performance of the battery cell.

[0017] In some embodiments, the second electrode lug and the bent section are located at the same end of the first connecting section in the first direction, wherein the second electrode lug is welded to the bent section and / or the second connecting section to form at least one fourth weld mark, and adjacent sub-electrodes in the second electrode lug are fixedly connected only through the fourth weld mark. In the above technical solution, by connecting the second electrode lug to the bent section and / or the second connecting section, the reliability of the connection between the first electrode lug and the first current collector can be improved; at the same time, the assembly steps can be simplified, and welding efficiency can be effectively improved.

[0018] In some embodiments, the first current collector is a flexible conductive connecting piece. This technical solution facilitates the bending and shaping of the first current collector, while mitigating breakage or cracking during bending or use. This improves the stability and lifespan of the first current collector, reducing the risk of unstable or failed connections between the electrode assembly and the first electrode terminal during use.

[0019] Secondly, this application provides a battery device that includes the battery cell described in the above embodiments.

[0020] Thirdly, this application provides an electrical device that includes the battery described in the above embodiments, the battery being used to provide electrical energy.

[0021] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0022] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic diagram of the electrical device provided in this application; Figure 2 A schematic diagram of the battery device provided in this application; Figure 3A schematic diagram of a single battery cell provided in this application; Figure 4 This is a cross-sectional view of a battery cell according to some embodiments of this application; Figure 5 This is a welding schematic diagram of a battery cell according to some embodiments of this application; Figure 6 This is another welding schematic diagram of a battery cell according to some embodiments of this application; Figure 7 This is yet another welding schematic diagram of a battery cell according to some embodiments of this application; Figure 8 This is another welding schematic diagram of a battery cell according to some embodiments of this application; Figure 9 This is a cross-sectional view of a battery cell according to other embodiments of this application; Figure 10 for Figure 9 A schematic diagram of a welding process for a single battery cell is shown. Figure 11 for Figure 9 Another welding schematic diagram of the battery cell shown; Figure 12 This is a cross-sectional view of a battery cell according to some embodiments of this application; Figure 13 for Figure 12 A schematic diagram of a welding process for a single battery cell is shown. Figure 14 for Figure 12 Another welding schematic diagram of the battery cell shown; Figure 15 This is a cross-sectional view of a battery cell according to some embodiments of this application; Figure 16 A schematic diagram showing the connection of the first electrode segment and the sub-electrode of the electrode assembly of a battery cell provided in some embodiments of this application after being unfolded; Figure 17 A cross-sectional view of the main body of the electrode assembly of a battery cell provided in some embodiments of this application, perpendicular to the thickness direction of the end cap; Figure 18 A cross-sectional view of the main body of the electrode assembly of a battery cell provided in some other embodiments of this application, perpendicular to the thickness direction of the end cap; Figure 19 This is a schematic diagram of a first current collector component provided for some embodiments of this application.

[0023] Figure label: Battery unit 1000, power supply unit 2000, casing 200, first casing body 210, second casing body 220. 100 cells per battery Outer shell 10, outer shell 11, end cap 12, Electrode assembly 20, main body 21, first electrode segment 2101, straight region 21a, bending region 21b, first electrode tab 22, sub-electrode tab 2201, first electrode tab portion 221, second electrode tab portion 222, first slot 223. First electrode terminal 30, First current collector 40, foil 401, first connecting section 41, bending section 42, second connecting section 43 First solder mark 51, second solder mark 52, third solder mark 53, fourth solder mark 54, fifth solder mark 55. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, rather than to describe a specific order or hierarchy.

[0026] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0028] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0029] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0030] In this application, "multiple" means two or more (including two).

[0031] In this application, a battery refers to a single physical module comprising one or more individual battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. Some batteries may include a housing for encapsulating one or more individual battery cells or multiple battery modules. The housing can prevent liquids or other foreign matter from affecting the charging or discharging of the individual battery cells. Of course, some batteries may not require the aforementioned housing and may be directly installed within the battery mounting compartment of the electrical device.

[0032] In this application, the battery cell may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and the embodiments of this application are not limited to these. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited to these. Battery cells are generally divided into three types according to their packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this application are not limited to these.

[0033] For example, a battery cell may include a casing, electrode assembly, and electrolyte. The casing houses the electrode assembly and electrolyte. The electrode assembly consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrode plates. The positive electrode includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector, and the uncoated positive current collector protrudes beyond the coated positive current collector, serving as the positive electrode tab. Taking a lithium-ion battery as an example, the positive current collector can be made of aluminum, and the positive active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc.

[0034] The negative electrode includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative current collector, and the negative current collector without the negative active material layer protrudes from the one with the negative active material layer. The negative current collector without the negative active material layer serves as the negative electrode tab. The material of the negative current collector can be copper, and the negative active material can be carbon or silicon, etc. To ensure that a large current can be passed without melting, there are multiple positive electrode tabs stacked together, and there are multiple negative electrode tabs stacked together.

[0035] The separator can be made of PP (polypropylene) or PE (polyethylene), etc. Furthermore, the electrode assembly can be a wound structure or a stacked structure; the embodiments of this application are not limited to these.

[0036] Battery cells can be equipped with electrode terminals or other components that connect to tabs, serving as electrical connections. Furthermore, battery cells can have pressure relief sections. When the internal pressure of the battery cell becomes excessive (e.g., thermal runaway), these sections release substances (e.g., gases, liquids, particulate matter) to reduce the internal pressure and prevent rapid pressurization that could lead to dangerous accidents such as battery cell explosion. For example, the pressure relief section can be an explosion-proof valve, explosion-proof plate, etc.

[0037] In traditional technology, when connecting the tabs to the terminals in a battery cell with multiple electrode components, the multiple sub-tabs of the tabs need to be gathered together before connecting them to the terminals. As the electrode components become thicker, gathering the tabs together can make the tabs too long. During manufacturing, the tabs are prone to folding, which can lead to the risk of cracking, increase the current transmission resistance, and reduce the performance of the battery cell.

[0038] Therefore, this application proposes a battery cell, comprising: an end cap; a first electrode terminal disposed on the end cap; a plurality of electrode assemblies, each electrode assembly including a main body and a first electrode tab, the main body including a plurality of first electrode segments stacked along a first direction and having the same polarity, the first electrode tab including a plurality of sub-electrode tabs, each sub-electrode tab of each first electrode tab being connected to one end of a first electrode segment near the end cap, at least some sub-electrode tabs being bent toward the same side along the first direction to form a first electrode tab portion, the portions of adjacent sub-electrode tabs in the first electrode tab portion being stacked along the thickness direction of the end cap, the first direction being perpendicular to the thickness direction of the end cap; and a first current collector. The component includes a first connecting segment, a bent segment, and a second connecting segment connected in sequence. The first connecting segment is stacked and connected to a first electrode ear along the thickness direction of the end cap. The second connecting segment is located on the side of the first connecting segment near the end cap and is connected to a first electrode terminal. The second connecting segment and the first connecting segment are connected by a bent segment, and the first connecting segment and the second connecting segment are located on the same side of the bent segment in a first direction. The first electrode terminal is connected to a first current collector and the first current collector is connected to multiple electrode assemblies, or the first electrode terminal is connected to two first current collectors and each first current collector is connected to at least one electrode assembly.

[0039] In the battery cell with the above-described structure, by setting at least a portion of the sub-tabs of the first tab in the form of a first tab portion, the height of each sub-tab is shortened. At the same time, a first current collector is provided between the first tab portion and the first electrode terminal, and the first tab and the first electrode terminal are connected through the first current collector, further shortening the height of the sub-tabs. By reducing the height of the sub-tabs, the risk of the first tab flipping is reduced, the probability of the first tab cracking leading to an increase in current transmission resistance is reduced, and the performance of the battery cell is improved. In addition, by shortening the height of the sub-tabs, it is also beneficial to increase the height of the main body, thereby increasing the energy density of the battery cell.

[0040] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. They can be used to form the power system of the electrical device, thereby ensuring the safety and reliability of the electrical device.

[0041] For example, the electrical devices disclosed in the embodiments of this application may be, but are not limited to, vehicles, mobile phones, tablets, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles may be fuel-powered vehicles, natural gas vehicles, new energy vehicles, or rail vehicles. New energy vehicles may be pure electric vehicles, hybrid vehicles, or range-extended vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0042] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the electrical device provided in this application. The electrical device can be a vehicle, which can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 1000 is installed inside the vehicle. The battery device 1000 can be located at the bottom, front, or rear of the vehicle. The battery device 1000 can be used to supply power to the vehicle; for example, it can serve as the vehicle's operating power source or general power source. The vehicle may also include a controller and a motor. The controller is used to control the battery device 1000 to supply power to the motor, for example, to meet the power needs of the vehicle during starting, navigation, and driving.

[0043] In some embodiments of this application, the battery device 1000 can not only serve as the operating power or power source for the vehicle, but also as the driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0044] Please refer to Figure 2 and Figure 3 , Figure 2 A schematic diagram of the battery device 1000 is provided for the purposes of this application. Figure 3 This is a schematic diagram of the battery cell 100 provided in this application. The battery device 1000 includes a housing 200 and battery cells 100, which are housed within the housing 200.

[0045] The housing 200 provides assembly space for the battery cell 100, and can adopt various structures. In some embodiments, the housing 200 may include a first housing body 210 and a second housing body 220, which overlap each other, and together define an assembly space for accommodating the battery cell 100. The second housing body 220 may be a hollow structure open at one end, and the first housing body 210 may be a plate-like structure, with the first housing body 210 covering the open side of the second housing body 220 so that the first housing body 210 and the second housing body 220 together define the assembly space; alternatively, the first housing body 210 and the second housing body 220 may both be hollow structures open on one side, with the open side of the first housing body 210 covering the open side of the second housing body 220.

[0046] Of course, the box 200 formed by the first box body 210 and the second box body 220 can be of various shapes, such as a cylinder, a cuboid, or a cube. For example, in the figure, the shape of the box 200 is a cuboid.

[0047] In the battery device 1000, there can be one or more battery cells 100 disposed within the housing 200. When there are multiple battery cells 100 disposed within the housing 200, they can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 100 are connected in both series and parallel configurations. Multiple battery cells 100 can be directly connected in series, in parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 100 is housed within the housing 200. Alternatively, the battery device 1000 can also consist of multiple battery cells 100 first connected in series, in parallel, or in a mixed configuration to form battery modules, and then multiple battery modules are connected in series, in parallel, or in a mixed configuration to form a whole, which is then housed within the housing 200.

[0048] In some embodiments, the battery device 1000 may also include other structures. For example, the battery device 1000 may also include a busbar component for connecting multiple battery cells 100 to achieve electrical connection between the multiple battery cells 100.

[0049] Each battery cell 100 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 100 can be in the form of a cuboid, a prism, or other shapes. For example, in the figure, the battery cell 100 has a cuboid structure.

[0050] The battery cell 100 includes a housing 10 and an electrode assembly 20 disposed within the housing 10. The housing 10 can also be used to contain an electrolyte, such as an electrolyte solution. The housing 10 can have various structural forms, such as a cuboid. Similarly, the housing 10 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy.

[0051] In some embodiments, the housing 10 can be a sealed structure or a non-sealed structure. As an example, when the housing 10 is a sealed structure, it can protect the electrode assembly 20 and prevent, to some extent, electrolyte leakage. When the housing 10 is a non-sealed structure, it can still protect the electrode assembly 20, and a sealing bag may be included between the housing 10 and the electrode assembly 20 to encapsulate the electrode assembly 20 and the electrolyte.

[0052] The housing 10 may include a housing 11 and an end cap 12. The housing 11 has an internal cavity for accommodating the electrode assembly 20 and has an opening. That is, the housing 11 is a hollow structure with an opening at one end. The end cap 12 covers the opening of the housing 11 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 20 and the electrolyte.

[0053] The housing 11 includes a bottom wall and a side wall. The bottom wall is disposed opposite to the end cap 12. The side wall surrounds the bottom wall, with one end of the side wall connected to the bottom wall and the other end forming an opening.

[0054] The housing 11 can have various shapes, such as a cuboid or prism structure. The shape of the housing 11 can be determined according to the specific shape of the electrode assembly 20. For example, in the figures and diagrams, the housing 11 is a cuboid structure, and correspondingly, the end cap 12 is a rectangular plate structure.

[0055] Of course, it is understandable that the outer casing 10 is not limited to the structure described above. The outer casing 10 can also be other structures. For example, the outer casing 10 may include a housing 11 and two end caps 12. The housing 11 is a hollow structure with openings on both opposite sides. One end cap 12 is fitted onto one opening of the housing 11 to form a sealed connection, thereby forming a sealed space for accommodating the electrode assembly 20 and the electrolyte. In other words, the housing 11 has openings on both opposite sides, and the two end caps 12 are fitted onto both sides of the housing 11 to close the corresponding openings.

[0056] Below, please refer to the appendix. Figures 4-19 This describes a battery cell 100 according to an embodiment of this application.

[0057] According to an embodiment of this application, a battery cell 100 includes: an end cap 12, a first electrode terminal 30, a plurality of electrode assemblies 20, and a first current collector 40. The first electrode terminal 30 is disposed on the end cap 12. Each electrode assembly 20 includes a main body 21 and a first tab 22. The main body 21 includes a plurality of first electrode segments 2101 stacked along a first direction F1 and having the same polarity. The first tab 22 includes a plurality of sub-tabs 2201. Each sub-tab 2201 of each first tab 22 is connected to one end of a first electrode segment 2101 near the end cap 12. At least some of the sub-tabs 2201 are bent toward the same side along the first direction F1 to form a first tab portion 221. The portions of adjacent sub-tabs 2201 in the first tab portion 221 are stacked along the thickness direction F2 of the end cap 12. The first direction F1 is perpendicular to the end cap 12. The thickness direction F2 of the end cap 12; the first current collector 40 includes a first connecting section 41, a bending section 42 and a second connecting section 43. The first connecting section 41 is stacked and connected to the first electrode ear 221 along the thickness direction F2 of the end cap 12. The second connecting section 43 is located on the side of the first connecting section 41 near the end cap 12 and is connected to the first electrode terminal 30. The second connecting section 43 and the first connecting section 41 are connected by the bending section 42, and the first connecting section 41 and the second connecting section 43 are located on the same side of the bending section 42 in the first direction F1. The first electrode terminal 30 is connected to one first current collector 40 and the first current collector 40 is connected to multiple electrode assemblies 20, or the first electrode terminal 30 is connected to two first current collectors 40 and each first current collector 40 is connected to at least one electrode assembly 20.

[0058] The battery cell 100 includes multiple electrode assemblies 20. The number of electrode assemblies 20 can be two or more. For example, in the figure, the electrode assembly 20 has a wound structure. Correspondingly, the electrode assembly 20 housed in the housing 10 can be two, three, four, five, six, seven, eight or more, and the multiple electrode assemblies 20 are stacked along the first direction F1.

[0059] The electrode assembly 20 includes a main body 21 and a first tab 22. The main body 21 is the main component of the electrode assembly 20 for chemical reactions to occur inside the battery cell 100. The electrode assembly 20 also includes a second tab. The first tab 22 and the second tab have opposite polarities. Both the first tab 22 and the second tab are connected to the main body 21 and are spaced apart.

[0060] The main body 21 of the electrode assembly 20 includes a first electrode, a second electrode, and a spacer. The first and second electrodes have opposite polarities, i.e., the first and second electrodes are the positive and negative electrodes of the electrode assembly 20, respectively. Optionally, the structure of the main body 21 of the electrode assembly 20 can be various. The main body 21 of the electrode assembly 20 can be a wound structure formed by winding the first electrode, the second electrode, and the spacer, or it can be a stacked structure formed by alternately arranging the first electrode, the second electrode, and the spacer. The spacer is disposed between the first electrode and the second electrode to insulate and isolate the first electrode and the second electrode.

[0061] The main body 21 includes a plurality of first electrode segments 2101 stacked along the first direction F1. The main body 21 of the electrode assembly 20 has a flat region 21a, which is a flat portion of the main body 21 of the electrode assembly 20.

[0062] For example, in Figure 17 In this structure, the electrode assembly 20 has a wound structure, and the central axis of the winding of the electrode assembly 20 extends along the thickness direction F2 of the end cap 12. Correspondingly, the main body 21 also has two bending regions 21b, and the two bending regions 21b are respectively connected to the two opposite ends of the straight region 21a in the third direction F3. The thickness direction F2, the first direction F1, and the third direction F3 of the end cap 12 are perpendicular to each other. Of course, if the electrode assembly 20 has a stacked structure, refer to... Figure 18 As shown, the entire main body 21 of the electrode assembly 20 is a flat region 21a, that is, the main body 21 of the electrode assembly 20 only includes the flat region 21a.

[0063] The first electrode includes multiple first electrode segments 2101 located in the flat region 21a. Correspondingly, if the electrode assembly 20 is a wound structure, the first electrode segment 2101 is the flat portion of the first electrode located in the flat region 21a, and the first electrode includes multiple first electrode segments 2101 located in the flat region 21a; if the electrode assembly 20 is a stacked structure, the electrode assembly 20 includes multiple first electrodes and multiple second electrodes, and the first electrodes and second electrodes are alternately and stacked along the first direction F1. Correspondingly, the first electrode segment 2101 is the first electrode.

[0064] The direction in which the first tab 22 protrudes from the main body 21 is the second direction F2, and the thickness direction F2 of the end cap 12 is as follows: Figure 4As shown in the second direction F2, the first electrode tab 22 protrudes from the main body 21 along the thickness direction F2 of the end cap 12. The first electrode tab 22 is connected to the first electrode plate, and the second electrode tab is connected to the second electrode plate. Optionally, the first electrode tab 22 and the second electrode tab are both connected to the same end of the main body 21 in the thickness direction F2 of the end cap 12. Of course, in other embodiments, the first electrode tab 22 and the second electrode tab can also be structures that are respectively connected to the two ends of the main body 21 in the thickness direction F2 of the end cap 12.

[0065] The first electrode tab 22 includes a plurality of sub-electrodes 2201 stacked together. The first electrode tab 22 of the electrode assembly 20 is a multi-layer metal foil structure connected to one end of the first electrode sheet in the thickness direction F2 of the end cap 12, that is, each layer of metal foil is a sub-electrode tab 2201.

[0066] The main body 21 includes a plurality of first pole segments 2101. Each sub-pole ear 2201 of each first pole ear 22 is connected to the end of a first pole segment 2101 near the end cap 12. That is, the first pole ear 22 is disposed at the end of the main body 21 facing the end cap 12 in the thickness direction F2. The sub-pole ear 2201 in the first pole ear 22 is a structure connected to the end of the corresponding first pole segment 2101 near the end cap 12 in the thickness direction F2. And one sub-pole ear 2201 in each first pole ear 22 is connected to one first pole segment 2101.

[0067] At least a portion of the sub-electrode tabs 2201 are bent toward the same side along the first direction F1 to form the first electrode tab portion 221. At least a portion of the sub-electrode tabs 2201 means that all the sub-electrode tabs 2201 can be bent toward the same side along the first direction F1. Of course, it can also be that a portion of the sub-electrode tabs 2201 are bent toward the same side along the first direction F1 to form the first electrode tab portion, while another portion of the sub-electrode tabs 2201 can be bent toward the other side along the first direction F1, or another portion of the sub-electrode tabs 2201 can be bent toward one side along the first direction F1 and then bent toward the other side.

[0068] In the first electrode ear portion 221, portions of adjacent sub-electrode ears 2201 are stacked along the thickness direction F2 of the end cap 12. That is, the extension direction of the sub-electrode ears 2201 in the first electrode ear portion 221 (from one end connected to the first electrode segment 2101 to the end away from the first electrode segment 2101) changes from extending along the thickness direction F2 of the end cap 12 to eventually transforming into a structure extending along the first direction F1. In other words, these sub-electrode ears 2201 in the first electrode ear portion 221 can be electrodes of equal height, without the need for the traditional extension towards the end of the electrode segment 2101. The extension of the main body 21 and the folding of all the sub-tabs 2201 mean that each sub-tab 2201 only needs to be bent and overlapped with the adjacent sub-tab 2201. This effectively shortens the height of each sub-tab 2201, reduces the risk of tab folding, and reduces the probability of tab cracking leading to increased current transmission resistance, thereby ensuring the performance of the battery cell 100 to a certain extent. In addition, by shortening the height of the sub-tabs 2201, it is also beneficial to increase the height of the main body 21, thereby increasing the energy density of the battery cell 100.

[0069] Here, at least a portion of the sub-electrode 2201 can be smoothed using a specialized smoothing device to form the first electrode portion 221.

[0070] The first electrode terminal 30 is disposed on the end cap 12, such as Figure 4 As shown, the first electrode terminal 30 passes through the first electrode lead-out hole of the end cover 12 and is insulated and mounted on the end cover 12. The first electrode terminal 30 serves to electrically connect to the first tab 22 of the electrode assembly 20, acting as the output or input electrode of the battery cell 100, thereby enabling the output or input of electrical energy from the battery cell 100. The first current collector 40 is disposed between the first tab 221 and the first electrode terminal 30. The first electrode terminal 30, the first current collector 40, and the first tab 221 are arranged sequentially in the thickness direction F2 of the end cover 12.

[0071] A portion of the first current collector 40 is connected to the first tab 22, which includes a first tab portion 221, meaning a portion of the first current collector 40 is connected to the first tab portion 221. A portion of the first current collector 40 is also connected to the first electrode terminal 30, serving to connect the first electrode terminal 30 and the first tab 22, thereby achieving an electrical connection between the first electrode terminal 30 and the electrode assembly 20.

[0072] In other words, by providing a first current collector 40 between the first tab 221 and the first electrode terminal 30, the connection difficulty between the first electrode terminal 30 and the first tab 22 can be reduced. At the same time, the first tab 221 does not need to be directly connected to the first electrode terminal 30, which can further reduce the height of the first tab 221 protruding from the main body 21 and the height of each sub-tab 2201 protruding from the first electrode segment 2101, thereby reducing the tab height, reducing the risk of tab folding, and improving the performance of the battery cell 100. In addition, the first current collector 40 is provided on the side of the first tab 221 away from the main body 21, that is, the first current collector 40 and the first tab 221 can be connected on the outside of the first tab 221 (the side away from the main body 21), which facilitates the connection between the two, improves manufacturability, and helps to improve the reliability of the connection.

[0073] like Figure 4 As shown, the first electrode terminal 30 is connected to a first current collector 40, and the first current collector 40 is connected to four electrode assemblies 20. Of course, when the first electrode terminal 30 is connected to a first current collector 40, the first current collector 40 can also connect to two, three or more electrode assemblies 20, thereby realizing the connection of multiple electrode assemblies 20 to the first electrode terminal 30. At the same time, at least a portion of the sub-tabs 2201 of each electrode assembly 20 is designed in the form of a first tab portion 221, which shortens the height of each sub-tab 2201, thereby reducing the risk of the first tab 22 of each electrode assembly 20 being bent, and reducing the probability of the first tab 22 cracking leading to an increase in current transmission resistance.

[0074] like Figure 9 and Figure 12 As shown, the first electrode terminal 30 is connected to two first current collectors 40, and each first current collector 40 is connected to an electrode assembly 20, such as... Figure 15 As shown, the first electrode terminal 30 is connected to two first current collectors 40, and each first current collector 40 is connected to two electrode assemblies 20. Of course, each first current collector 40 can also connect to more electrode assemblies 20. The number of electrode assemblies 20 connected to the two first current collectors 40 can be the same or different. This allows multiple electrode assemblies 20 to be connected to the first electrode terminal 30. At the same time, at least a portion of the sub-tabs 2201 of each electrode assembly 20 is designed as a first tab portion 221, which shortens the height of each sub-tab 2201, thereby reducing the risk of the first tab 22 of each electrode assembly 20 being bent and reducing the probability of the first tab 22 cracking leading to an increase in current transmission resistance.

[0075] The first current collector 40 includes a first connecting segment 41, a bent segment 42, and a second connecting segment 43 connected in sequence. The second connecting segment 43 is located on the side of the first connecting segment 41 facing the first electrode terminal 30. The first connecting segment 41 and the second connecting segment 43 are located on the same side of the bent segment 42 in the first direction F1, such that the first connecting segment 41, the bent segment 42, and the second connecting segment 43 are connected in sequence to form a U-shaped structure. Figure 4 As shown, the second connecting segment 43 and the first connecting segment 41 are arranged along the thickness direction F2 of the end cap 12. The first connecting segment 41 is the part of the first current collector 40 used to overlap and connect with the first electrode ear 221 in the thickness direction F2 of the end cap 12, while the second connecting segment 43 is the part of the first current collector 40 used to connect with the first electrode terminal 30.

[0076] The first connecting segment 41 and the first electrode lug 221 are stacked along the thickness direction F2 of the end cap 12. The first connecting segment 41 and the first electrode lug 221 can be welded together or connected by conductive adhesive or other means. The second connecting segment 43 and the first electrode terminal 30 are stacked along the thickness direction F2 of the end cap 12. The second connecting segment 43 and the first electrode terminal 30 can be welded together or connected by conductive adhesive or other means. This achieves an electrical connection between the first electrode lug 22 and the first electrode terminal 30.

[0077] The first current collector 40 can be connected and assembled with the first tab 22 and the first electrode terminal 30, and then bent to form a bent section 42. That is, the first connecting section 41, the bent section 42 and the second connecting section 43 are connected in sequence and integrally formed. The second connecting section 43, the bent section 42 and the first connecting section 41 are formed by bending the same substrate.

[0078] Therefore, the battery cell 100 can first unfold the first current collector 40, and after the first current collector 40 is connected to the first tab 22 and the first electrode terminal 30, the first current collector 40 is bent to form a bent section 42. Then, the assembled electrode assembly 20 and end cap 12 and other components are assembled into the housing 11 of the battery cell 100. This facilitates the connection and assembly of the first connecting section 41 and the first tab 221 from one side of the first current collector 40. At the same time, the second connecting section 43 and the first electrode terminal 30 can be connected and assembled from one side of the first current collector 40, thereby effectively reducing the welding difficulty between the first current collector 40 and the first tab 221 and the first electrode terminal 30.

[0079] According to the embodiments of this application, the battery cell 100 shortens the height of each sub-tab 2201 by setting at least a portion of the sub-tab 2201 of the first tab 22 of the plurality of electrode assemblies 20 as a first tab portion 221. At the same time, a first current collector 40 is provided between the first tab portion 221 and the first electrode terminal 30, and the first tab 22 and the first electrode terminal 30 are connected by the first current collector 40, further shortening the height of the sub-tab 2201. By reducing the height of the sub-tab 2201, the risk of the first tab 22 being flipped is reduced, the probability of the first tab 22 cracking leading to an increase in current transmission resistance is reduced, and the performance of the battery cell 100 is improved. In addition, by shortening the height of the sub-tab 2201, it is also beneficial to increase the height of the main body 21, thereby increasing the energy density of the battery cell 100.

[0080] In some embodiments, the battery cell 100 may further include a second electrode terminal electrically connected to a second tab of the electrode assembly, such that the second electrode terminal and the first electrode terminal can cooperate to input or output electrical energy from the battery cell. In some embodiments, the battery cell 100 may further include a second current collector, which serves to connect the second electrode terminal and the second tab to achieve electrical connection between the second electrode terminal and the electrode assembly, thereby reducing the difficulty of connecting the second electrode terminal and the second tab.

[0081] The second electrode can have the same structure as the first electrode. Similarly, the assembly structure between the second current collector and the second electrode terminal, as well as between the second current collector and the second electrode, can be the same as the assembly structure between the first current collector 40 and the first electrode terminal 30, and between the first current collector 40 and the first electrode 22.

[0082] like Figures 9-15 As shown, in some embodiments, the first electrode terminal 30 is connected to two first current collectors 40, and the bent sections 42 of the two first current collectors 40 are arranged opposite to each other.

[0083] like Figure 9 and Figure 12 As shown, a first electrode terminal 30 is simultaneously connected to two first current collectors 40, and each first current collector 40 is connected to one electrode assembly 20, thereby allowing the first electrode terminal 30 to be electrically connected to both electrode assemblies 20; as Figure 15 As shown, a first electrode terminal 30 is simultaneously connected to two first current collectors 40, and each first current collector 40 is connected to two electrode assemblies 20, thereby the first electrode terminal 30 can be electrically connected to four electrode assemblies 20.

[0084] The bent sections 42 of the two first current collector components 40 are arranged opposite each other, and the first connecting section 41 and the second connecting section 43 of each first current collector component 40 are located on the side of the bent section 42 facing the other first current collector component 40. Taking the first direction as the left-right direction as an example, as follows... Figure 9 and Figure 12 As shown, the first current collector 40 includes two parts, left and right. In the left first current collector 40, the first connecting section 41 and the second connecting section 43 are located to the right of the bent section 42. In the right first current collector 40, the first connecting section 41 and the second connecting section 43 are located to the left of the bent section 42.

[0085] During the assembly of the battery cell 100, before the two first current collectors 40 are connected to the first tabs 22 of the corresponding electrode assemblies 20, the two first current collectors 40 are arranged symmetrically, for example, the two first current collectors 40 are arranged left and right, so that the first connecting segment 41 on the left is located to the left of the second connecting segment 43 on the left. Correspondingly, the electrode assembly 20 is located to the left of the first current collector 40, which facilitates the connection between the first tab 22 and the first current collector 40. The first connecting segment 41 on the right is located to the right of the second connecting segment 43 on the right. Correspondingly, the electrode assembly 20 is arranged to the right of the first current collector 40, which facilitates the connection between the first tab 22 and the first current collector 40.

[0086] After the first current collector 40 is connected to the first electrode tab 22, it is folded so that each electrode assembly 20 is arranged on one side of the first electrode terminal 30 in the thickness direction F2 of the end cover 12, while the bent sections 42 of the two first current collectors 40 are arranged opposite each other.

[0087] In the above technical solution, the bent sections 42 of the two first current collectors 40 are arranged opposite to each other, which makes it easier to connect each first current collector 40 with the corresponding electrode assembly 20 and improves assembly efficiency.

[0088] like Figure 9 As shown, in some embodiments, the first tab 221 connected to each first current collector 40 is bent toward the side closer to the other first current collector 40.

[0089] like Figures 9-11As shown, the bending section 42 is connected to the first end of the first connecting section 41. The sub-tabs 2201 of each electrode assembly 20 are bent toward the second end of the first connecting section 41. The two electrode assemblies 20 are roughly flattened inward (towards each other). Specifically, for the connection of a first current collector 40 and an electrode assembly 20, each sub-tab 2201 of the first tab 221 is flattened toward the second end of the first connecting section 41. A portion of the sub-tab 2201 can also form a second tab 222. The second tab 222 is located at the second end of the first connecting section 41. The second tab 222 can be connected to the first connecting section 41. The second tab 222 and the bending section 42 of the electrode assembly 20 are located at both ends of the first connecting section 41 in the first direction F1.

[0090] In the above technical solution, the first tab 22 of each electrode assembly 20 can be connected to the first connecting segment 41, which not only facilitates the assembly and connection of the two, but also improves the reliability of the connection between the first tab 22 and the first connecting segment 41.

[0091] like Figure 12 As shown, in some embodiments, the first tab 221 connected to each first current collector 40 is bent toward the side away from the other first current collector 40.

[0092] like Figures 12-14 As shown, the bending section 42 is connected to the first end of the first connecting section 41. The sub-tabs 2201 of each electrode assembly 20 are bent toward the first end of the first connecting section 41. The two electrode assemblies 20 are flattened outward (away from each other). Specifically, for the connection of a first current collector 40 and an electrode assembly 20, each sub-tab 2201 of the first tab 221 is flattened toward the first end of the first connecting section 41. A portion of the sub-tab 2201 can also form a second tab 222. The second tab 222 is located at the first end of the first connecting section 41. The second tab 222 can be connected to the bending section 42 and the second connecting section 43. The second tab 222 and the bending section 42 of the electrode assembly 20 are located at the same end of the first connecting section 41 in the first direction F1.

[0093] In the above technical solution, the first tab 221 of the two electrode assemblies 20 can be bent and flattened in a direction away from the other electrode assembly 20, which can reduce the probability of interference between the tabs inside the battery cell 100.

[0094] like Figure 4 and Figure 15As shown, in some embodiments, the first current collector 40 connects to a plurality of first tabs 22 of a plurality of electrode assemblies 20, the sub-tabs 2201 of the plurality of first tabs 22 are bent in the same direction, and portions of the first tabs 22 of two adjacent electrode assemblies 20 are stacked along the thickness direction F2 of the end cap 12.

[0095] like Figure 4 As shown, the first electrode terminal 30 is connected to a first current collector 40, and the first current collector 40 is connected to four electrode assemblies 20, thereby allowing the first electrode terminal 30 to be electrically connected to the four electrode assemblies 20; as Figure 15 As shown, each first current collector 40 is connected to two electrode assemblies 20, and a first electrode terminal 30 is simultaneously connected to two first current collectors 40, thereby the first electrode terminal 30 can be electrically connected to four electrode assemblies 20.

[0096] Among them, the sub-tabs 2201 of the multiple first electrode tabs 22 can be smoothed by a smoothing device, so that the multiple sub-tabs 2201 bend in the same direction, reducing the probability of interference between the sub-tabs 2201 of two adjacent electrode assemblies 20, and also facilitating the connection between the multiple electrode assemblies 20 and the first current collector 40; some sub-tabs 2201 of one electrode assembly 20 can be bent and overlapped on the sub-tabs 2201 of the adjacent electrode assembly 20, thereby eliminating the need to increase the height of the sub-tabs 2201 of any electrode assembly 20 and reducing the risk of tab flipping.

[0097] In the above technical solution, each first electrode terminal 30 can be connected to multiple electrode assemblies 20. The sub-tabs 2201 of adjacent electrode assemblies 20 are bent in the same direction and overlapped. This facilitates the connection between the tabs and the first current collector 40, and eliminates the need to increase the height of the sub-tabs 2201 of any electrode assembly 20, thus reducing the risk of tab folding.

[0098] like Figure 8 , Figure 11 and Figure 14 As shown, in some embodiments, the first current collector 40 and the first electrode terminal 30 are welded together, and the first current collector 40 and the first electrode terminal 30 are welded together to form a fifth solder mark 55. Exemplarily, the fifth solder mark 55 is a solder mark structure formed by laser welding of the first current collector 40 and the first electrode terminal 30, such as... Figure 8 As shown, the connection between the first current collector 40 and the first electrode terminal 30 can be made from the side of the first current collector 40 away from the first electrode terminal 30. Thus, after subsequent assembly, the fifth solder part 55 can be built into the housing 10 of the battery cell 100, thereby reducing the risk of rusting of the fifth solder part 55 during use and the risk of leakage of the battery cell 100 at the location of the fifth solder part 55.

[0099] It should be noted that, Figure 8 , Figure 11 and Figure 14 In order to clearly see the fifth solder mark 55, the first solder mark 51 and other solder marks from the previous step are not shown, not because these solder marks do not exist.

[0100] like Figure 6 , Figure 10 and Figure 13 As shown, in some embodiments, the first electrode tab 221 is welded to the first connecting section 41 to form at least one first solder mark 51, and adjacent sub-electrode tabs 2201 in the first electrode tab 221 are fixedly connected only through the first solder mark 51.

[0101] like Figure 6 , Figure 10 and Figure 13 As shown, the first electrode tab 221 and the first connecting segment 41 are stacked on each other in the second direction F2. Each first solder mark 51 can pass through the first connecting segment 41. The first electrode tab 221 and the first connecting segment 41 can be connected by the first solder mark 51. Correspondingly, the first solder mark 51 is the area where the first electrode tab 221 and the first connecting segment 41 are welded together to form a fused area or a solder mark area.

[0102] For example, the first solder mark 51 is a solder mark structure formed by laser welding of the first connecting section 41 and the first electrode tab 221.

[0103] Welding can be performed on the side of the first connecting section 41 away from the first electrode ear 221, so that welding can be performed on the outside of the first electrode ear 221 (the side away from the main body 21), which effectively reduces the welding difficulty between the first current collector 40 and the first electrode ear 221 and improves manufacturing efficiency.

[0104] In the projection plane perpendicular to the thickness direction F2 of the end cap 12, the orthographic projection of the first solder mark 51 can be strip-shaped. That is, the orthographic projection of the first solder mark 51 in the projection plane perpendicular to the thickness direction F2 of the end cap 12 is a long strip-shaped structure extending along a straight line or an arc trajectory. This enables the first solder mark 51 to be interconnected with more sub-tabs 2201 to improve the current flow effect between the first tab 221 and the first connecting section 41.

[0105] In the first electrode tab 221, two adjacent sub-electrode tabs 2201 are fixedly connected only through the first solder mark 51. That is, after the portions of multiple sub-electrode tabs 2201 are stacked along the second direction F2, two adjacent sub-electrode tabs 2201 are fixedly connected only through the first solder mark 51, without any other fixing structure. This makes it possible that before the first connecting section 41 and the first electrode tab 221 are welded to form the first solder mark 51, the stacked and adjacent sub-electrode tabs 2201 are a structure that is not fixed to each other and can move and separate relative to each other.

[0106] In the above technical solution, after the sub-electrode 2201 is bent towards the first direction F1 to form the first electrode ear portion 221, and before the first electrode ear portion 221 is stacked and welded with the first connecting section 41, the multiple sub-electrode ears 2201 of the first electrode ear portion 221 are not fixedly connected or pre-welded. This is to facilitate the smoothing and bending of the multiple sub-electrode ears 2201 of the first electrode ear 22 before welding and assembling the first electrode ear portion 221 and the first connecting section 41. This allows the multiple sub-electrode ears 2201 to have relative movement and lateral movement capabilities during the smoothing and bending process, enabling each... The individual tab 2201 can adapt to the length change caused by bending during the smoothing and bending process, so as to reduce the phenomenon of local stress concentration or local bulging of the individual tab 2201 during the smoothing and bending process. This can effectively improve the welding quality between the first tab 221 and the first connecting section 41, and effectively alleviate the phenomenon of cracking or breakage of the individual tab 2201 during assembly or use. This reduces the risk of unstable connection and connection failure between the first tab 22 and the first connecting section 41 during use, which is conducive to improving the stability and reliability of the battery cell 100.

[0107] In addition, the multiple sub-tabs 2201 of the first tab 221 do not need to be fixedly connected or pre-welded, which can avoid the cracking problem caused by direct welding of the first tab 221, reduce the probability of cracks appearing in the first tab 22, reduce the probability of increased current transmission resistance caused by tab cracking, and ensure the performance of the battery cell 100 to a certain extent.

[0108] like Figures 4-14 As shown, in some embodiments, a plurality of sub-taperes 2201 extend to the side of the first connecting section 41 away from the main body 21 to form a second taper 222, and the second taper 222 is located on one side of the first taper 221 in the first direction F1 and is connected to the first current collector 40.

[0109] like Figures 4-14As shown, in the first electrode tab 22, a portion of the sub-electrode tab 2201 is bent toward the same side along the first direction F1 to form a first electrode tab portion 221. The first electrode tab portion 221 is connected to the first connecting section 41 of the first current collector 40. Another portion of the sub-electrode tab 2201 that is not connected to the first connecting section 41 forms a second electrode tab portion 222. In the first direction F1, the second electrode tab portion 222 is located on one side of the first electrode tab portion 221. In the second direction F2, the second electrode tab portion 222 extends to the side of the first connecting section 41 away from the main body portion 21.

[0110] The second electrode ear 222 is connected to the first current collector 40, such as Figure 7 and Figure 10 As shown, the second pole ear 222 can be connected to the first connecting segment 41, as... Figure 13 and Figure 14 As shown, the second tab 222 can be connected to the bent section 42 and the second connecting section 43, thereby connecting all the sub-tabs 2201 of the first tab 22 to the first current collector 40, and further connecting all the sub-tabs 2201 of the first tab 22 to the first electrode terminal 30, maximizing the output or input of electrical energy from the battery cell 100. It should be noted that... Figure 14 To clearly show the bent section 42 and the fifth solder mark 55, which are not shown. Figure 13 The first solder mark 51 and the fourth solder mark 54 are present, not that the first solder mark 51 and the fourth solder mark 54 do not exist.

[0111] In the above technical solution, by setting the second electrode ear 222, a part of the first electrode ear 22 can be extended to the side of the first connecting section 41 away from the first electrode ear 221 for connection, which is beneficial to reduce the size of the first current collector 40 in the first direction F1, reduce the space occupied by the first current collector 40, and at the same time improve the reliability of the connection between the first electrode ear 22 and the first current collector 40.

[0112] like Figures 4-11 As shown, in some embodiments, the second electrode ear 222 and the bent section 42 are located at both ends of the first connecting section 41 in the first direction F1, wherein a first slot 223 is formed between the second electrode ear 222 and the first electrode ear 221, and the end of the first connecting section 41 away from the bent section 42 is inserted into the first slot 223.

[0113] like Figures 4-11As shown, in the first direction F1, the first end of the first connecting segment 41 is connected to the second connecting segment 43 through the bending segment 42. The second end of the first connecting segment 41 is a free end. Each sub-pole tab 2201 of the first pole tab 221 is smoothed towards the second end of the first connecting segment 41. The second pole tab 222 is located at the second end of the first connecting segment 41 and can be connected to the first connecting segment 41.

[0114] Understandably, by connecting the second tab 222 to the first connecting segment 41, the reliability of the connection between the first tab 22 and the first connecting segment 41 is improved. At the same time, the first tab 22 only needs to be connected to the first connecting segment 41, and the first tab 22 will not be affected by the bending of the first current collector 40, reducing the probability of the outer sub-tab 2201 of the first tab 22 being torn. In addition, the second tab 222 will not be sandwiched between the first current collector 40 and the first electrode terminal 30, which can avoid the gap between the first electrode terminal 30 and the first current collector 40 affecting the connection between the two.

[0115] The sub-tab 2201 of the second tab 222 is bent in the opposite direction to the sub-tab 2201 of the first tab 221, thereby forming a first slot 223 between the second tab 222 and the first tab 221. After the first tab 22 and the first current collector 40 are assembled and connected, one end of the first connecting section 41 is in a plug-in state with the first slot 223. This improves the reliability of the connection between the first current collector 40 and the first tab 22 during the use of the battery cell 100 and reduces the probability of power output or input being blocked due to relative movement or separation.

[0116] It should be noted that when assembling the first electrode tab 22 and the first connecting section 41, the first connecting section 41 of the first current collector 40 can be first attached to the first electrode tab 221, and then the second electrode tab 222 can be bent to the upper surface of the first connecting section 41, forming a first slot 223 between the second electrode tab 222 and the first electrode tab 221, thereby forming a state in which the first connecting section 41 and the first slot 223 are inserted and engaged; in other examples, after the sub-electrode tab 2201 is smoothed by the smoothing device, it can be... After the flattened end of the sub-electrode 2201 is extended outward (away from the main body 21), a second electrode 222 is formed. The second electrode 222 is then bent in the opposite direction, and the other part of the flattened sub-electrode 2201 forms a first electrode 221. At the same time, a first slot 223 is formed between the second electrode 222 and the first electrode 221. Then, one end of the first connecting section 41 of the first current collector 40 is inserted into the first slot 223, and the first connecting section 41 is made to fit against the first electrode 221.

[0117] In the above technical solution, by forming a first slot 223 between the second electrode ear 222 and the first electrode ear 221, the first connecting segment 41 can be inserted and engaged with the first slot 223, thereby improving the reliability of the connection between the first electrode ear 22 and the first connecting segment 41.

[0118] like Figure 5 As shown, in some embodiments, a plurality of sub-tabs 2201 of the second tab portion 222 are welded together to form at least one second solder mark portion 52.

[0119] like Figure 5 As shown, the multiple sub-taps 2201 of the second electrode tab 222 are pre-welded to form a second weld mark 52. Adjacent sub-taps 2201 in the second electrode tab 222 are fixedly connected through the second weld mark 52. Correspondingly, the second weld mark 52 is the area where the multiple sub-taps 2201 of the second electrode tab 222 are welded together to form a fused area or a weld mark area. For example, the second weld mark 52 is a weld mark structure formed by ultrasonic welding of multiple sub-taps 2201.

[0120] It should be noted that, Figure 6 In order to clearly see the first solder mark 51, Figure 7 To clearly show the third solder mark 53, it is not marked. Figure 5 The second solder mark 52 is present, not that the second solder mark 52 does not exist.

[0121] In the above technical solution, by welding the multiple sub-tabs 2201 of the second electrode ear 222, the multiple sub-tabs 2201 are not easy to separate, which makes it easier for the second electrode ear 222 to be bent and connected to the first current collector 40, and at the same time improves the reliability of the connection between the second electrode ear 222 and the first current collector 40.

[0122] like Figure 7 and Figure 10 As shown, in some embodiments, the second electrode ear 222 is welded to the first connecting section 41 to form at least one third solder mark 53.

[0123] like Figure 7 and Figure 10 As shown, the second electrode lug 222 and the first connecting segment 41 are stacked on each other in the second direction F2. Each third solder mark 53 can pass through the second electrode lug 222. The second electrode lug 222 and the first connecting segment 41 can be connected by the third solder mark 53. Correspondingly, the third solder mark 53 is the area where the second electrode lug 222 and the first connecting segment 41 are welded together to form a fused area or a solder mark area.

[0124] For example, the third solder mark 53 is a solder mark structure formed by laser welding of the second electrode tab 222 and the first connecting section 41.

[0125] For example, the plurality of third solder marks 53 can be dot-shaped solder marks arranged at intervals, and the third solder marks 53 can be formed on the second solder marks 52, that is, the third solder marks 53 can overlap with the second solder marks 52.

[0126] It should be noted that the first solder mark 51 and the third solder mark 53 can be obtained by welding in stages, or they can be formed by welding simultaneously using the same equipment. For example, as shown... Figures 6-7 As shown, the first electrode lug 221 can be welded to the first connecting section 41 first to form the first solder mark 51. Then, the second electrode lug 222 is bent to the upper surface of the first connecting section 41, and then the second electrode lug 222 is welded to the first connecting section 41 to form the third solder mark 53. It should be noted that... Figure 7 To clearly show the third solder mark 53, it is not shown. Figure 6 The first solder mark 51 in the image, not that the first solder mark 51 is absent; for example, as shown in the image. Figure 10 As shown, the lower surface of the first connecting segment 41 can be attached to the first electrode lug 221, and the second electrode lug 222 can be bent to the upper side of the first electrode lug 221, so that the second electrode lug 222 is attached to the upper surface of the first connecting segment 41. At this time, the second electrode lug 222, the first connecting segment 41, and the first electrode lug 221 are simultaneously welded to form the first solder mark 51 and the third solder mark 53. The first electrode lug 221 and the first connecting segment 41 are connected through the first solder mark 51, and the second electrode lug 222 and the first connecting segment 41 are connected through the third solder mark 53. It should be noted that during the... Figure 10 During the welding process shown, the second electrode lug 222 can be welded first. Figure 5 The welding shown.

[0127] In the above technical solution, by welding the second tab 222 to the first connecting section 41, the reliability of the connection between the first tab 22 and the first connecting section 41 is improved, and the performance of the battery cell 100 is improved.

[0128] like Figures 12-15 As shown, in some embodiments, the second electrode lug 222 and the bent section 42 are located at the same end of the first connecting section 41 in the first direction F1, wherein the second electrode lug 222 is welded to the bent section 42 and / or the second connecting section 43 to form at least one fourth solder mark 54, and adjacent sub-electrode lugs 2201 in the second electrode lug 222 are fixedly connected only through the fourth solder mark 54.

[0129] like Figures 12-15As shown, in the first direction F1, the first end of the first connecting segment 41 is connected to the second connecting segment 43 through the bending segment 42. The second end of the first connecting segment 41 is a free end. Each sub-pole tab 2201 of the first pole tab 221 is smoothed towards the first end of the first connecting segment 41. The second pole tab 222 is located at the first end of the first connecting segment 41. The second pole tab 222 can be connected to the bending segment 42, or to the second connecting segment 43, or simultaneously to both the bending segment 42 and the second connecting segment 43.

[0130] The second electrode lug 222 is welded to the bent section 42 and / or the second connecting section 43 to form at least one second solder mark 52, and adjacent sub-electrode lugs 2201 in the second electrode lug 222 are fixedly connected only by the fourth solder mark 54.

[0131] like Figure 13 and Figure 14 As shown, the bent section 42 and the second connecting section 43 are attached to the outside of the second electrode lug 222, so that the second electrode lug 222 and the first current collector 40 are stacked on each other. Each fourth solder mark 54 can pass through the first current collector 40, and the fourth solder mark 54 and the first current collector 40 can be connected through the fourth solder mark 54. Correspondingly, the fourth solder mark 54 is the area where the second electrode lug 222 and the first current collector 40 are welded together to form a fused area or a solder mark area.

[0132] For example, the fourth solder mark 54 is a solder mark structure formed by laser welding of the second electrode ear 222 and the first current collector 40.

[0133] For example, the fourth solder mark 54 can be an elongated structure extending along a straight line or an arc, thereby enabling the fourth solder mark 54 to be interconnected with more sub-tabs 2201 to improve the flow effect between the second tab 222 and the first current collector 40.

[0134] It should be noted that the first solder mark 51 and the fourth solder mark 54 can be obtained by welding in stages, or they can be formed by welding simultaneously using the same equipment, such as... Figure 13 As shown, along the extension direction of the first current collector 40, the welding equipment welds the first connecting section 41 to the first pole lug 221 from the second end to the first end. At the first end, the bending section 42 is directly welded to the second pole lug 222, and then the second connecting section 43 is welded to the second pole lug 222. This simplifies the assembly steps and effectively improves the welding efficiency.

[0135] In the second electrode ear portion 222, two adjacent sub-electrode ears 2201 are fixedly connected only through the fourth solder mark portion 54. That is, two adjacent sub-electrode ears 2201 are fixedly connected only through the fourth solder mark portion 54, without any other fixing structure. This makes it possible for the two adjacent sub-electrode ears 2201 to be stacked and not fixed to each other and to move and separate relative to each other before the first current collector 40 and the second electrode ear portion 222 are welded together to form the fourth solder mark portion 54. This facilitates the second electrode ear portion 222 to be fitted and welded to the bent section 42.

[0136] In the above technical solution, by connecting the second electrode lug 222 with the bent section 42 and / or the second connecting section 43, the reliability of the connection between the first electrode lug 22 and the first current collector 40 can be improved; at the same time, the assembly steps can be simplified and the welding efficiency can be effectively improved.

[0137] In some embodiments, the first collector 40 is adapted to be pre-bent at the bend 42.

[0138] Before connecting the first current collector 40 to the first electrode terminal 30 and the first tab 22, the middle part of the first current collector 40 is pre-bent at a small angle. For example, Figures 6-8 The bending section 42 shown is not bent directly to the final size. One side of the pre-bent section is then connected to the first tab 22, and the other side is connected to the first electrode terminal 30. After the first current collector 40 is connected to the first electrode terminal 30 and the first tab 22, the first current collector 40 is then bent to the final size, forming... Figure 4 The bent segment 42 is shown.

[0139] In the above technical solution, by pre-bending at the bending section 42, the deformation resistance of the bending section 42 can be reduced, and the difficulty of bending the bending section 42 of the first current collector 40 can be reduced, so that the first current collector 40 can be bent to form the bending section 42 after the first current collector 40 is welded to the first tab 22 and the first electrode terminal 30.

[0140] like Figure 19 As shown, in some embodiments, the first current collector 40 is a flexible conductive connecting piece.

[0141] Flexible conductive connectors are conductive connection components that are bendable, deformable, and flexible. Compared to traditional rigid copper or aluminum busbars, flexible conductive connectors are easier to bend and can deform with vibrations and other factors during assembly. Figure 19 As shown, the first current collector 40 can be a multi-layer foil 401 stacked structure. The multi-layer foil 401 can be welded together to form an integral first current collector 40. The foil 401 can be metal foil such as copper foil or aluminum foil. The first current collector 40 can also be a braided metal wire, etc.

[0142] In the above technical solution, it is beneficial to bend and form the first current collector 40, and at the same time, it can alleviate the phenomenon of breakage or cracking during bending or use, thereby improving the stability and service life of the first current collector 40, and reducing the risk of unstable connection or connection failure of the electrode assembly 20 and the first electrode terminal 30 during use. The battery device 1000 according to the second aspect of the present application includes the battery cell 100 according to the first aspect of the present application. Therefore, by using the battery cell 100, it is beneficial to improve the performance of the battery device 1000 and increase the energy density of the battery device 1000.

[0143] The power supply device 2000 according to a third aspect embodiment of this application includes a battery device 1000 according to the first aspect embodiment of this application, the battery device 1000 being used to provide power to the power supply device 2000. Therefore, by employing the battery device 1000, the reliability and battery life of the power supply device 2000 are improved.

[0144] The following description, in conjunction with the accompanying drawings, describes a specific embodiment of a battery device 1000 and a vehicle having therein according to the present application.

[0145] like Figure 1 As shown, the battery unit 1000 is located at the bottom of the vehicle, and as... Figure 3 and Figure 9 As shown, the battery device 1000 includes a housing 200 and a battery cell 100, the battery cell 100 being housed within the housing 200.

[0146] The battery cell 100 includes a housing 10, a first electrode terminal 30, two electrode assemblies 20 and two first current collectors 40. The housing 10 includes a shell 11 and an end cap 12. The first electrode terminal 30 is disposed on the end cap 12. The two first current collectors 40 correspond one-to-one with the two electrode assemblies 20. Each first current collector 40 includes a first connecting section 41, a bending section 42 and a second connecting section 43 connected in sequence.

[0147] like Figure 9 As shown, each electrode assembly 20 includes a main body 21 and a first electrode tab 22. The main body 21 includes a plurality of first electrode segments 2101 stacked along the first direction F1 and having the same polarity. The first electrode tab 22 includes a plurality of sub-electrode tabs 2201. Each sub-electrode tab 2201 of each first electrode tab 22 is connected to one end of a first electrode segment 2101 near the end cap 12.

[0148] By using a smoothing device, a portion of the sub-electrode tabs 2201 are bent towards the same side along the first direction F1 to form a first electrode tab portion 221. Adjacent portions of the sub-electrode tabs 2201 in the first electrode tab portion 221 are stacked along the thickness direction F2 of the end cap 12. Multiple sub-electrode tabs 2201 extend away from the main body portion 21 to form a second electrode tab portion 222. For example... Figure 5 As shown, the multiple sub-tabs 2201 of the second electrode tab 222 are pre-welded, and after welding, the second solder mark 52 is formed.

[0149] like Figure 6 As shown, the first connecting segment 41 is attached to the first electrode lug 221. The first connecting segment 41 and the first electrode lug 221 are stacked along the second direction F2. The first electrode lug 221 and the first connecting segment 41 are welded together to form at least one first solder mark 51. The adjacent sub-electrode lugs 2201 in the first electrode lug 221 are fixedly connected only through the first solder mark 51. It can be understood that before the first solder mark 51 is formed, the second electrode lug 222 may not be folded onto the surface of the first connecting segment 41.

[0150] like Figure 6 and Figure 7 As shown, after the first solder mark 51 is formed, the second electrode ear 222 is bent to the surface of the first connecting section 41, and a first slot 223 is formed between the second electrode ear 222 and the first electrode ear 221. At this time, the first connecting section 41 and the first slot 223 are inserted and engaged. Then, the second electrode ear 222 and the first connecting section 41 are soldered together to form the third solder mark 53.

[0151] Subsequently, the welded electrode assembly 20 and the first current collector 40 are placed on the first electrode terminal 30 of an end cap 12, and the second connecting section 43 and the first electrode terminal 30 are welded together to form the fifth solder mark 55; Figure 11 As shown, the two first current collectors 40 are connected in the same way, and the two first current collectors 40 are arranged opposite to each other.

[0152] Finally, fold the end cap 12 or the two electrode assemblies 20 to bend the first current collector 40, forming a shape as shown. Figure 9 The battery cell 100 shown here has a first current collector 40 located between the first tab 221 and the first electrode terminal 30, and a second connecting section 43 located on the side of the first connecting section 41 facing the first electrode terminal 30.

[0153] In the above technical solution, the height of each sub-tab 2201 can be shortened. At the same time, the first tab 22 and the first electrode terminal 30 are connected through the first current collector 40, further shortening the height of the sub-tab 2201. By reducing the height of the sub-tab 2201, the risk of the first tab 22 being flipped is reduced, the probability of the first tab 22 cracking leading to an increase in current transmission resistance is reduced, and the performance of the battery cell 100 is improved. In addition, by shortening the height of the sub-tab 2201, it is also beneficial to increase the height of the main body 21, thereby increasing the energy density of the battery cell 100.

[0154] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell (100), characterized in that, include: End cap (12); The first electrode terminal (30) is disposed on the end cap (12); Multiple electrode assemblies (20), each electrode assembly (20) includes a main body (21) and a first electrode tab (22). The main body (21) includes multiple first electrode segments (2101) stacked along a first direction and having the same polarity. The first electrode tab (22) includes multiple sub-electrode tabs (2201). Each sub-electrode tab (2201) of each first electrode tab (22) is connected to one end of a first electrode segment (2101) near the end cap (12). At least a portion of the sub-electrode tabs (2201) are bent toward the same side along the first direction to form a first electrode tab portion (221). The portions of adjacent sub-electrode tabs (2201) in the first electrode tab portion (221) are stacked along the thickness direction of the end cap (12). The first direction is perpendicular to the thickness direction of the end cap (12). The first current collector (40) includes a first connecting segment (41), a bent segment (42), and a second connecting segment (43) connected in sequence. The first connecting segment (41) and the first electrode lug (221) are stacked and connected along the thickness direction of the end cap (12). The second connecting segment (43) is located on the side of the first connecting segment (41) closer to the end cap (12) and is connected to the first electrode terminal (30). The first connecting segment (41) and the second connecting segment (43) are located on the same side of the bent segment (42) in the first direction. Wherein, the first electrode terminal (30) is connected to one first current collector (40) and the first current collector (40) is connected to a plurality of the electrode assemblies (20), or the first electrode terminal (30) is connected to two first current collectors (40) and each first current collector (40) is connected to at least one of the electrode assemblies (20).

2. The battery cell (100) according to claim 1, characterized in that, The first electrode terminal (30) is connected to two first current collectors (40), and the bent sections (42) of the two first current collectors (40) are arranged opposite to each other.

3. The battery cell (100) according to claim 2, characterized in that, The first tab (221) connected to each of the first current collectors (40) bends toward the side closer to the other first current collector (40).

4. The battery cell (100) according to claim 2, characterized in that, The first tab (221) connected to each of the first current collectors (40) bends toward the side away from the other first current collector (40).

5. The battery cell (100) according to claim 1, characterized in that, The first current collector (40) connects to a plurality of first tabs (22) of a plurality of electrode assemblies (20), the sub-tabs (2201) of the plurality of first tabs (22) are bent in the same direction, and portions of the first tabs (22) of two adjacent electrode assemblies are stacked along the thickness direction of the end cap (12).

6. The battery cell (100) according to claim 1, characterized in that, The first electrode lug (221) is welded to the first connecting section (41) to form at least one first solder mark (51), and the adjacent sub-electrodes (2201) in the first electrode lug (221) are fixedly connected only through the first solder mark (51).

7. The battery cell (100) according to claim 1, characterized in that, The plurality of said sub-taperes (2201) extend to the side of the first connecting section (41) opposite to the main body (21) to form a second taper (222), and the second taper (222) is located on the side of the first taper (221) in the first direction and is connected to the first current collector (40).

8. The battery cell (100) according to claim 7, characterized in that, The second pole lug (222) and the bent segment (42) are located at both ends of the first connecting segment (41) in the first direction. A first slot (223) is formed between the second pole ear (222) and the first pole ear (221), and one end of the first connecting segment (41) away from the bent segment (42) is inserted into the first slot (223).

9. The battery cell (100) according to claim 8, characterized in that, The plurality of said sub-tabs (2201) of the second electrode tab (222) are welded together to form at least one second solder mark (52).

10. The battery cell (100) according to claim 9, characterized in that, The second electrode ear (222) is welded to the first connecting section (41) to form at least one third solder mark (53).

11. The battery cell (100) according to claim 7, characterized in that, The second pole lug (222) and the bent segment (42) are located at the same end of the first connecting segment (41) in the first direction. The second electrode lug (222) is welded to the bent section (42) and / or the second connecting section (43) to form at least one fourth solder mark (54), and the adjacent sub-electrodes (2201) in the second electrode lug (222) are fixedly connected only through the fourth solder mark (54).

12. The battery cell (100) according to any one of claims 1-11, characterized in that, The first current collector (40) is a flexible conductive connecting piece.

13. A battery device (1000), characterized in that, Includes the battery cell (100) according to any one of claims 1-12.

14. An electrical appliance (2000), characterized in that, Includes the battery device (1000) according to claim 13, the battery device (1000) being used to provide electrical energy.

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