Battery monomer, battery device and electric device

Abstract

The utility model relates to the technical field of batteries, and provides a battery monomer, a battery device and a power utilization device. The battery cell comprises: a housing having an accommodating cavity, the accommodating cavity having an opening; the end cover covers the opening; the electrode assembly is contained in the containing cavity, multiple layers of tabs are formed on the side, facing the end cover, of the electrode assembly, the multiple layers of tabs are provided with at least two tab welding areas, the at least two tab welding areas are arranged at intervals in the direction from the tabs to the end cover, and the tab welding areas are arranged at intervals in the direction from the tabs to the end cover. The number of layers of the tabs welded in at least two tab welding areas is gradually reduced, and the tabs in one tab welding area adjacent to the end cover are connected with the end cover in a welding manner. According to the technical scheme, the risk of short circuit caused by sudden increase of current can be reduced, the use stability of the single battery is improved, the structure of a product can be simplified, and the production cost of the product is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery monomer, a battery device and a power utilization device. BACKGROUND

[0002] The part provided in this section is merely background information related to the present disclosure, which does not necessarily have to be prior art.

[0003] At present, in the traditional battery monomer, the battery monomer is usually welded and connected with the lug and the adapter piece, and then the adapter piece is welded and connected with the electrode terminal of the battery monomer, wherein a fuse device is usually arranged on the adapter piece, and when the circuit of the battery monomer is short-circuited, the fuse device can be fused to realize short-circuit protection. However, this setting mode also leads to the complex structure of the end cover of the battery monomer, and after the fuse device is fused, a new fuse device needs to be replaced or the battery monomer needs to be directly scrapped, which is high in cost. Content of the utility model

[0004] The purpose of the present application is to provide a battery monomer, a battery device and a power utilization device, so as to simplify the structure of the battery monomer and reduce the use cost. The purpose is realized by the following technical scheme:

[0005] In a first aspect, the present application provides a battery monomer, comprising: a shell having a containing cavity, the containing cavity having an opening; an end cover covering the opening; an electrode assembly accommodated in the containing cavity, and a plurality of layers of lugs are formed on the side of the electrode assembly facing the end cover, wherein the plurality of layers of lugs have at least two lug welding areas, the at least two lug welding areas are arranged at intervals along the direction from the lug to the end cover, the number of layers of the lug welded by the at least two lug welding areas gradually decreases along the direction from the lug to the end cover, and the lug of the lug welding area adjacent to the end cover is welded and connected with the end cover.

[0006] According to the battery cell provided in the application, at least two tab welding areas are arranged on the multi-layer tab, the at least two tab welding areas are arranged at intervals along the direction from the tab to the end cover, and the number of layers of the tab welded by the at least two tab welding areas gradually decreases along the direction from the tab to the end cover, that is, the number of layers of the tab welded by the tab welding area closest to the end cover is the least, and the tab after welding in this part can play a role similar to a fuse. Therefore, when the tab welded by the tab welding area closest to the end cover is welded and connected with the end cover, if a short circuit occurs in the external circuit, the tab welded closest to the end cover can limit the current flow, reduce the current flow, and limit the maximum current, thereby reducing the risk of short circuit caused by sudden increase of current and improving the stability of the battery cell.

[0007] In addition, the battery cell provided in the application can also have the following additional technical features:

[0008] In some embodiments of the application, the at least two tab welding areas include a first tab welding area and a second tab welding area, the second tab welding area is arranged closer to the end cover than the first tab welding area, all the tabs are welded and connected through the first tab welding area, and the difference between the number of layers of the tab welded by the second tab welding area and the number of layers of the tab welded by the first tab welding area is not less than 2.

[0009] In the above technical solution, the first tab welding area is welded and connected with all the tabs, the number of layers of the tab welded by the second tab welding area is less than the number of layers of the tab welded by the first tab welding area, and the difference between them is not less than 2 layers, so that the number of layers of the tab welded by the second tab welding area is relatively small, and the tab welded by the second tab welding area is welded and connected with the end cover, thereby reducing the current flow to reduce the risk of short circuit caused by excessive current flow, and thereby improving the safety and stability of the battery cell.

[0010] In some embodiments of the application, the number of layers of the tab welded by the second tab welding area is arranged in the range of 5%-95% of the total number of layers of the tab.

[0011] In the above technical solution, the number of layers of the tab welded by the second tab welding area is arranged in the range of 5%-95% of the total number of layers of the tab, which can make the current flow through the conducting tab and the end cover on the one hand, and limit the maximum current flow on the other hand, thereby reducing the risk of short circuit caused by excessive current.

[0012] In some embodiments of the present application, the number of layers of the tab welded by the second tab welding area is arranged in the range of 20%-40% of the total number of layers of the tab.

[0013] In the above technical solution, the number of tabs welded by the second tab welding area determines the maximum current that can pass through, and by arranging the number of layers of the tab welded by the second tab welding area in the range of 20%-40% of the total number of layers of the tab, the number of layers of the tab welded by the second tab welding area is appropriately reduced, which not only improves the connection strength of the tab and the end cover welded and connected by the first tab welding area, but also reduces the risk of short circuit caused by excessive current flowing through the tab.

[0014] In some embodiments of the present application, the multi-layer tab is arranged in a stepped manner from one side to the other side along the thickness direction of the shell, and the height of the tab located in the first tab welding area is less than the height of the tab located in the second tab welding area along the direction of the tab to the end cover.

[0015] In the above technical solution, the height of the tab gradually increases from the first tab welding area to the second tab welding area along the direction of the tab to the end cover, and at this time, only the height of the tab in the second tab welding area needs to meet the welding height requirement with the end cover, and the height of the tab in the first tab welding area can be appropriately reduced, thereby reducing the risk of folding, bending or winding deformation of the tab.

[0016] In some embodiments of the present application, the at least two tab welding areas further include a third tab welding area, and the third tab welding area is arranged between the first tab welding area and the second tab welding area, wherein the number of layers of the tab welded by the third tab welding area is less than the number of layers of the tab welded by the first tab welding area, and greater than the number of layers of the tab welded by the second tab welding area.

[0017] In the above technical solution, by arranging the third tab welding area between the first tab welding area and the second tab welding area, and arranging the number of layers of the tab welded by the first tab welding area, the third tab welding area and the second tab welding area to gradually decrease, the flow of the current flowing from the end cover to the tab gradually increases, which plays a role in smoothing the current flow, thereby further improving the stability of the current flow, and further helping to improve the safety and stability of the battery monomer.

[0018] In some embodiments of the present application, the height of the tab located in the third tab welding area is less than the height of the tab located in the second tab welding area, and greater than the height of the tab located in the first tab welding area along the direction of the tab to the end cover.

[0019] In the technical solution, the height of the tab welded by the first tab welding area, the third tab welding area and the second tab welding area gradually increases, and the height of the tab of the first tab welding area and the third tab welding area can be set to be relatively low, so that the risk of bending deformation or winding of the tab can be reduced.

[0020] In some embodiments of the present application, the end cover is provided with an electrode terminal, and the tab of the first tab welding area is welded and connected with the electrode terminal.

[0021] In the technical solution, the tab of the first tab welding area can be welded and connected with the electrode terminal on the end cover by laser welding after the welding is completed, so that the conduction of the current can be realized, and the structure and principle are relatively simple and easy to realize.

[0022] In a second aspect, the present application provides a battery device comprising the battery monomer according to any one of the embodiments of the first aspect.

[0023] According to the battery device provided by the present application, since the battery monomer according to any one of the embodiments of the first aspect is included, the technical effects of any one of the embodiments are also possessed, which will not be repeated here.

[0024] In a third aspect, the present application provides a power consumption device comprising the battery device according to the above embodiments, and the battery device is used to supply power for the power consumption device.

[0025] According to the power consumption device provided by the present application, since the battery device according to any one of the embodiments of the first aspect is included, the technical effects of any one of the embodiments are also possessed, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0026] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not intended to limit the scope of the present application. Moreover, the same reference numerals are used throughout the same figures to designate similar or equivalent parts. In the drawings:

[0027] Figure 1 A structural schematic diagram of a vehicle is provided for some embodiments of the present application;

[0028] Figure 2 An exploded structural schematic diagram of a battery device is provided for some embodiments of the present application;

[0029] Figure 3 An exploded structural schematic diagram of a battery monomer is provided for some embodiments of the present application;

[0030] Figure 4 A structural diagram of an electrode assembly according to some embodiments of the present application;

[0031] Figure 5 A structural diagram of another electrode assembly according to some embodiments of the present application.

[0032] Reference signs are as follows:

[0033] 1000, vehicle;

[0034] 100, battery device; 200, control device; 300, motor;

[0035] 10, case; 11, first case; 12, second case; 20, battery cell; 21, end cap; 21a, electrode terminal; 22, housing; 23, electrode assembly; 23a, tab;

[0036] 231, first tab welding area; 232, second tab welding area; 233, third tab welding area. DETAILED DESCRIPTION

[0037] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0039] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0040] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0041] In the description of the embodiments of the present application, the term "and / or" is merely an association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are an "or" relationship.

[0042] In the description of the embodiments of the present application, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0043] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0044] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0045] At present, from the development of market situation, the application of battery device is more and more widely. The battery device is not only applied to the energy storage power supply system of hydropower, thermal power, wind power and solar power station, but also widely applied to electric bicycles, electric motorcycles, electric vehicles and other electric vehicles, military equipment, aerospace and other fields. With the continuous expansion of the application field of battery device, the demand of its market is also increasing.

[0046] In the related art, a battery device usually includes a plurality of battery monomers, the tab of the battery monomer is usually welded with a adapter piece, and then the adapter piece is welded with the electrode terminal of the battery monomer, wherein a fuse device is usually arranged on the adapter piece, and when the circuit of the battery monomer is short-circuited, the fuse device can be fused to realize short-circuit protection. However, this setting mode also causes the end cover structure of the battery monomer to be complex, and after the fuse device is fused, a new fuse device needs to be replaced or the battery monomer needs to be directly scrapped, which is high in cost.

[0047] In order to solve the problems of complex structure and high cost of the conventional battery monomer, the application designs a battery monomer, which includes a shell, an end cover and an electrode assembly, the shell has a containing cavity, the electrode assembly is accommodated in the containing cavity, and the end cover is arranged at the opening of the containing cavity, wherein the side of the electrode assembly facing the end cover is formed with a plurality of layers of tabs, the plurality of layers of tabs have at least two tab welding areas which are arranged at intervals in the direction from the tab to the end cover, the number of layers of the tabs welded by the at least two tab welding areas is gradually reduced in the direction from the tab to the end cover, and the tab welded by one tab welding area adjacent to the end cover is welded with the end cover, the number of layers of the tabs of the tab welding area is relatively small, which can limit the passage of large current, thereby reducing the problem of internal circuit short circuit of the battery monomer caused by sudden increase of current, and the mode that the tab is welded with the end cover through the adapter piece is cancelled, the structure of the battery monomer is simplified, and the production cost is reduced.

[0048] The battery monomer disclosed in the embodiments of the application can be used in, but is not limited to, an electric device such as a vehicle, a ship or an aircraft. The power supply system of the electric device can be composed of the battery monomer, the battery device and the like disclosed in the application, which helps to reduce the production cost of the battery device and improve the stability of the battery performance.

[0049] The embodiments of the application provide an electric device using a battery as a power supply. The electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft and the like. The electric toy can include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy and an electric plane toy and the like, and the spacecraft can include an airplane, a rocket, a space shuttle and a spacecraft and the like.

[0050] The following embodiments take a vehicle 1000 as an example for convenience of description.

[0051] Please refer to Figure 1 , Figure 1A structural schematic diagram of a vehicle 1000 is provided for some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle, or a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle, or a range extended vehicle, etc. The vehicle 1000 is internally provided with a battery apparatus 100, which can be arranged at the bottom, head, or tail of the vehicle 1000. The battery apparatus 100 can be used for power supply of the vehicle 1000, for example, the battery apparatus 100 can be used as an operating power source of the vehicle 1000. The vehicle 1000 can further include a control apparatus 200 and a motor 300, and the control apparatus 200 is used to control the battery apparatus 100 to supply power to the motor 300, for example, to meet the working power demand of the vehicle 1000 during starting, navigation, and driving.

[0052] In some embodiments of the present application, the battery apparatus 100 can not only be used as an operating power source of the vehicle 1000, but also be used as a driving power source of the vehicle 1000, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1000.

[0053] Please refer to Figure 2 , Figure 2 A disassembled structural schematic diagram of the battery apparatus 100 is provided for some embodiments of the present application. The battery apparatus 100 (Battery Apparatus) mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly (Battery Cell Assembly) can include a plurality of battery cells 20 connected in series, in parallel, or in a mixed connection mode through a busbar component.

[0054] In some embodiments, the battery cell assembly (Battery Cell Assembly) is usually formed by arranging a plurality of battery cells 20.

[0055] As an example, the battery cell assembly can be a battery module (Battery Module), which is formed by arranging and fixing a plurality of battery cells 20 into an independent module. As an example, the battery module can be formed by bundling a plurality of battery cells 20 with a cable tie.

[0056] In some embodiments, the battery apparatus 100 can be a battery pack (battery Pack), which includes a box body and one or more battery cell assemblies accommodated in the box body.

[0057] As an example, the battery cell assembly can be accommodated in the box body by fixing the battery module in the box body.

[0058] As an example, the battery cell assembly can also be accommodated in the box body by directly fixing a plurality of battery cells 20 in the box body.

[0059] As an example, the box 10 can include a first box 11 and a second box 12. The first box 11 and the second box 12 are buckled so that an enclosed space is formed inside the box 10 to accommodate the battery monomer assembly. The enclosed here means covered or closed, which can be sealed or unsealed. The first box 11 can be a cover plate or a bottom plate.

[0060] As an example, the box 10 can also include a frame. The first box 11 and the second box 12 are respectively connected with the frame, so that an enclosed space is formed inside the box 10 to accommodate the battery monomer assembly.

[0061] In some embodiments, the box 10 can be part of the chassis structure of the vehicle. For example, part of the box can be at least part of the bottom plate of the vehicle, or part of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0062] The technical solutions described in the embodiments of the present application are applicable to various electric devices using battery monomers 20, such as mobile phones, portable devices, notebook computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc. For example, the spacecraft includes airplanes, rockets, space shuttles and spaceships, etc.

[0063] In the battery device 100, the battery monomers 20 can be multiple, and the multiple battery monomers 20 can be connected in series, in parallel or in a mixed manner. The mixed manner means that the multiple battery monomers 20 are connected in series and in parallel. The multiple battery monomers 20 can be directly connected in series, in parallel or in a mixed manner, and then the whole of the multiple battery monomers 20 is accommodated in the box; of course, the battery device 100 can also be that the multiple battery monomers 20 are connected in series, in parallel or in a mixed manner to form a battery module, and then the multiple battery modules are connected in series, in parallel or in a mixed manner to form a whole, and the whole is accommodated in the box. The battery device 100 can also include other structures, for example, the battery device 100 can also include a current collecting component for realizing the electrical connection between the multiple battery monomers 20.

[0064] Please refer to Figure 3 and Figure 4 , Figure 4 the exploded structural schematic diagram of the battery monomer provided by some embodiments of the present application; Figure 4A structural schematic diagram of an electrode assembly is provided for some embodiments of the present application. Embodiments of the present application provide a battery monomer 20, which includes a shell 22, an end cover 21 and an electrode assembly 23. The shell 22 has a receiving cavity with an opening, the end cover 21 is arranged on the opening, and the electrode assembly 23 is accommodated in the receiving cavity. The side of the electrode assembly 23 facing the end cover 21 is formed with a plurality of layers of tabs 23a, and the plurality of layers of tabs 23a have at least two tab welding areas. The at least two tab welding areas are arranged at intervals along the direction of the tabs 23a to the end cover 21. In the direction of the tabs 23a to the end cover 21, the number of layers of tabs 23a welded by the at least two tab welding areas gradually decreases, and the tabs 23a of one tab welding area adjacent to the end cover 21 are welded and connected with the end cover 21.

[0065] In embodiments of the present application, the battery monomer 20 can be a secondary battery, which refers to a battery monomer 20 that can be activated by charging after discharging to continue to be used.

[0066] For example, the battery monomer 20 can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc. Embodiments of the present application are not limited thereto.

[0067] For example, the battery monomer 20 can be in the shape of a cylinder, a flat body, a cuboid or other shapes, etc.

[0068] The battery monomer 20 refers to the smallest unit that constitutes a battery. For example, Figure 3 The battery monomer 20 includes an end cover 21, a shell 22, an electrode assembly 23 and other functional components.

[0069] The end cover 21 refers to a component that covers the opening of the shell 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cover 21 can be adapted to the shape of the shell 22 to fit the shell 22. Optionally, the end cover 21 can be made of a material with certain hardness and strength, such as aluminum alloy, so that the end cover 21 is not easily deformed when subjected to extrusion collision, so that the battery cell 20 can have higher structural strength, and the safety performance can also be improved. The end cover 21 can be provided with functional components such as electrode terminals 21a. The electrode terminals 21a can be used to electrically connect with the electrode assembly 23 for outputting or inputting the electrical energy of the battery cell 20. In some embodiments, the end cover 21 can also be provided with a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The material of the end cover 21 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not make special limitations. In some embodiments, an insulating member can also be provided on the inner side of the end cover 21, which can be used to isolate the electrical connection components in the shell 22 from the end cover 21 to reduce the risk of short circuit. For example, the insulating member can be plastic, rubber, etc.

[0070] The shell 22 is a component for fitting the end cover 21 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 23, electrolyte and other components. The shell 22 and the end cover 21 can be independent components, and an opening can be provided on the shell 22, and the end cover 21 is covered on the opening to form the internal environment of the battery cell 20. Without limitation, the end cover 21 and the shell 22 can also be integrated, specifically, the end cover 21 and the shell 22 can form a common connecting surface before other components enter the shell, and when it is necessary to seal the inside of the shell 22, the end cover 21 is covered on the shell 22. The shell 22 can be various shapes and various sizes, such as rectangular, cylindrical, hexagonal, etc. Specifically, the shape of the shell 22 can be determined according to the specific shape and size of the electrode assembly 23. The material of the shell 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not make special limitations.

[0071] The electrode assembly 23 is a component in which electrochemical reactions occur in the battery cell 20. The electrode assembly 23 includes a positive electrode, a negative electrode, and a separator disposed between the negative electrode and the positive electrode. During the charging and discharging process of the battery cell 20, active ions (such as lithium ions) are embedded and extracted between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can prevent the positive and negative electrodes from short-circuiting, and at the same time allows the active ions to pass through.

[0072] The housing 22 can contain one or more electrode assemblies 23. The electrode assembly 23 can be a wound structure, a stacked structure, or a hybrid structure of a wound and a stacked structure.

[0073] In some embodiments, the electrode assembly 23 is a wound structure. The positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0074] In some embodiments, the electrode assembly 23 is a stacked structure.

[0075] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets can be provided, and the plurality of positive electrode sheets and the plurality of negative electrode sheets can be alternately stacked.

[0076] As an example, a plurality of positive electrode sheets can be provided, and the negative electrode sheet can be folded to form a plurality of folded segments that are stacked. One positive electrode sheet can be interposed between adjacent folded segments.

[0077] As an example, both the positive electrode sheet and the negative electrode sheet can be folded to form a plurality of folded segments that are stacked.

[0078] As an example, a plurality of separators can be provided, and each of the plurality of separators can be interposed between any adjacent positive electrode sheet or negative electrode sheet.

[0079] As an example, a separator can be continuously provided, and the separator can be interposed between any adjacent positive electrode sheet or negative electrode sheet by being folded or wound.

[0080] In some embodiments, the electrode assembly 23 can have a cylindrical shape, a flat shape, or a polygonal shape.

[0081] In some embodiments, the electrode assembly 23 can be provided with a tab 23a through which current can be discharged from the electrode assembly 23. The tab 23a can include a positive tab and a negative tab.

[0082] The first tab welding area 231 and the second welding area refer to an area for welding the tab 23a.

[0083] The battery monomer 20 provided by the embodiments of the present application is provided with at least two tab welding areas on the multilayer tab 23a, the at least two tab welding areas are arranged at intervals along the direction of the tab 23a to the end cover 21, and the number of layers of the tab 23a welded by the at least two tab welding areas gradually decreases in the direction of the tab 23a to the end cover 21, that is, the number of layers of the tab 23a welded by the tab welding area closest to the end cover 21 is the least, and the tab 23a after welding of this part can play a role similar to a fuse, so that when the tab 23a welded by the tab welding area closest to the end cover 21 is welded and connected with the end cover 21, if a short circuit occurs in the external circuit, the fewer tab 23a welded closest to the end cover 21 can play a role in limiting the current flow, reducing the current flow, and limiting the maximum current, thereby reducing the risk of short circuit caused by sudden increase of current, and improving the stability of the battery monomer 20. In addition, since the mode of electrically connecting the tab 23a with the end cover 21 through the adapter piece is cancelled, the tab 23a located in the first tab welding area 231 is directly welded and connected with the end cover 21, so that the structure of the product can be simplified, and the production cost of the product can be reduced.

[0084] Please refer to Figure 4 According to some embodiments of the present application, the at least two tab welding areas include a first tab welding area 231 and a second tab welding area 232, the second tab welding area 232 is arranged closer to the end cover 21 than the first tab welding area 231, all the tabs 23a are welded and connected through the first tab welding area 231, and the difference between the number of layers of the tab 23a welded by the second tab welding area 232 and the number of layers of the tab 23a welded by the first tab welding area 231 is not less than 2.

[0085] The first tab welding area 231 is welded and connected with all the tabs 23a, the number of layers of the tab 23a welded by the second tab welding area 232 is less than the number of layers of the tab 23a welded by the first tab welding area 231, and the difference between them is not less than a layer, so that the number of layers of the tab 23a of the second tab welding area 232 is relatively small, and the tab 23a of the second tab welding area 232 is welded and connected with the end cover 21, thereby playing a role in reducing the current flow, reducing the risk of short circuit caused by excessive current flow, and further improving the safety and stability of the battery monomer 20.

[0086] According to some embodiments of the present application, the number of layers of the tab 23a welded by the second tab welding area 232 is arranged in the range of 5%-95% of the total number of layers of the tab 23a.

[0087] The number of the tab 23a welded by the second tab welding area 232 is set in the range of 5%-95% of the total number of the tab 23a, on the one hand, so that the current can pass through and turn on the tab 23a and the end cover 21, and on the other hand, the maximum current passing through can be limited, thereby reducing the risk of short circuit caused by excessive current.

[0088] According to some embodiments of the present application, the number of the tab 23a welded by the second tab welding area 232 is set in the range of 20%-40% of the total number of the tab 23a.

[0089] The number of the tab 23a welded by the second tab welding area 232 determines the maximum current that can pass through, by setting the number of the tab 23a welded by the second tab welding area 232 in the range of 20%-40% of the total number of the tab 23a, the number of the tab 23a welded by the second tab welding area 232 is appropriately reduced, not only can improve the connection strength of the tab 23a and the end cover 21 welded by the first tab welding area 231, but also can reduce the risk of short circuit caused by excessive current passing through the tab 23a.

[0090] According to some embodiments of the present application, the multi-layer tab 23a is arranged in a stepped manner from one side to the other side along the thickness direction of the shell 22, wherein along the direction of the tab 23a to the end cover 21, the height of the tab 23a located in the first tab welding area 231 is less than the height of the tab 23a located in the second tab welding area 232.

[0091] The height of the tab 23a located in the first tab welding area 231 is less than the height of the tab 23a located in the second tab welding area 232, that is, the distance between the tab 23a of the first tab welding area 231 and the top cover is greater than the distance between the tab 23a of the second welding area and the top cover.

[0092] That is, along the direction of the tab 23a to the end cover 21, the height of the tab 23a gradually increases from the first tab welding area 231 to the second tab welding area 232, at this time, only the height of the tab 23a of the second tab welding area 232 needs to be adjusted to meet the welding height requirement with the end cover 21, and the height of the tab 23a located in the first tab welding area 231 can be appropriately reduced, thereby reducing the risk of folding, bending or winding deformation of the tab 23a.

[0093] Please refer to Figure 5 , Figure 5A structural schematic diagram of an electrode assembly is provided for some embodiments of the present application. According to some embodiments of the present application, the at least two tab welding areas further include a third tab welding area 233, which is arranged between the first tab welding area 231 and the second tab welding area 232, and the number of layers of the tab 23a welded by the third tab welding area 233 is less than the number of layers of the tab 23a welded by the first tab welding area 231 and greater than the number of layers of the tab 23a welded by the second tab welding area 232.

[0094] By arranging the third tab welding area 233 between the first tab welding area 231 and the second tab welding area 232, and gradually reducing the number of layers of the tab 23a welded by the first tab welding area 231, the third tab welding area 233 and the second tab welding area 232, the current flow to the tab 23a from the end cover 21 gradually increases, which plays a role in smoothing the current flow, thereby further improving the stability of the current flow, and further helping to further improve the safety and stability of the battery monomer 20.

[0095] According to some embodiments of the present application, in the direction from the tab 23a to the end cover 21, the height of the tab 23a located in the third tab welding area 233 is less than the height of the tab 23a located in the second tab welding area 232, and greater than the height of the tab 23a located in the first tab welding area 231.

[0096] That is, the height of the tab 23a welded by the first tab welding area 231, the third tab welding area 233 and the second tab welding area 232 gradually increases, and the height of the tab 23a welded by the first tab welding area 231 and the third tab welding area 233 can be relatively low, thereby reducing the risk of bending deformation or winding of the tab 23a.

[0097] According to some embodiments of the present application, the end cover 21 is provided with an electrode terminal 21a, and the tab 23a of the first tab welding area 231 is welded and connected with the electrode terminal 21a.

[0098] For example, the tab 23a welded by the first tab welding area 231 is laser welded and connected with the electrode terminal 21a.

[0099] After the welding of the tab 23a of the first tab welding area 231 is completed, the tab 23a can be welded and connected with the electrode terminal 21a on the end cover 21 by laser welding, thereby realizing the conduction of the current, and the structure and principle are relatively simple and easy to realize.

[0100] According to some embodiments of the present application, referring to Figures 3 to 4The application provides a battery monomer 20, which comprises a shell 22, an end cover 21 and an electrode assembly 23. The shell 22 has a containing cavity, and the containing cavity has an opening; the end cover 21 is arranged on the opening, and the end cover 21 is provided with an electrode terminal 21a; the electrode assembly 23 is arranged in the containing cavity, and a side of the electrode assembly 23 facing the end cover 21 is formed with a plurality of layers of tabs 23a; the plurality of layers of tabs 23a have at least two tab welding areas, the at least two tab welding areas comprise a first tab welding area 231 and a second tab welding area 232 which are arranged at intervals along the direction of the tabs 23a to the end cover 21, the second tab welding area 232 is located between the first tab welding area 231 and the top cover, the number of layers of the tabs 23a welded by the first tab welding area 231 and the second tab welding area 232 gradually decreases along the direction of the tabs 23a to the end cover 21, the height of the tabs 23a welded by the first tab welding area 231 is smaller than the height of the tabs 23a welded by the second tab welding area 232, and the tabs 23a welded by the first tab welding area 231 are welded and connected with the electrode terminal 21a of the end cover 21. By adopting the above technical scheme, the structure of the battery monomer 20 can be simplified, the production cost of the product can be reduced, the risk of internal circuit short circuit of the battery monomer 20 can be reduced, and the safety of the battery monomer 20 can be improved.

[0101] The above merely describes the preferred embodiments of the application, but the protection scope of the application is not limited thereto, and any changes or replacements within the technical scope disclosed by the application can be easily thought of by those skilled in the art, which should be covered in the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. A battery cell, characterized in that, include: A housing having a receiving cavity having an opening; An end cap is provided over the opening; An electrode assembly is housed within the receiving cavity, and the electrode assembly has multiple layers of tabs formed on the side facing the end cap. The multi-layer electrode has at least two electrode welding areas, and the at least two electrode welding areas are spaced apart along the direction from the electrode to the end cap. Along the direction from the electrode to the end cap, the number of electrode layers welded in the at least two electrode welding areas gradually decreases, and the electrode in one electrode welding area adjacent to the end cap is welded to the end cap.

2. The battery cell according to claim 1, characterized in that, The at least two electrode welding areas include a first electrode welding area and a second electrode welding area. The second electrode welding area is located close to the end cap relative to the first electrode welding area. All the electrodes are welded together through the first electrode welding area. The difference between the number of electrode layers welded in the second electrode welding area and the number of electrode layers welded in the first electrode welding area is not less than 2.

3. The battery cell according to claim 2, characterized in that, The number of layers of the electrode welded in the second electrode welding area is set within the range of 5%-95% of the total number of electrode layers.

4. The battery cell according to claim 3, characterized in that, The number of layers of the electrode welded in the second electrode welding area is set within the range of 20%-40% of the total number of electrode layers.

5. The battery cell according to any one of claims 2-4, characterized in that, The multi-layered tabs converge from one side to the other along the thickness direction of the shell and are arranged in a stepped manner. Wherein, along the direction from the electrode tab to the end cap, the height of the electrode tab located in the first electrode tab welding area is less than the height of the electrode tab located in the second electrode tab welding area.

6. The battery cell according to claim 5, characterized in that, The at least two electrode tab welding areas also include a third electrode tab welding area, which is spaced between the first electrode tab welding area and the second electrode tab welding area. The number of electrode layers welded in the third electrode welding area is less than the number of electrode layers welded in the first electrode welding area, but greater than the number of electrode layers welded in the second electrode welding area.

7. The battery cell according to claim 6, characterized in that, Along the direction from the tab to the end cap, the height of the tab located in the third tab welding area is less than the height of the tab located in the second tab welding area, but greater than the height of the tab located in the first tab welding area.

8. The battery cell according to any one of claims 2-4, characterized in that, The end cap is provided with electrode terminals, and the electrode in the first electrode welding area is welded to the electrode terminals.

9. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1-8.

10. An electrical appliance, characterized in that, Includes the battery device as described in claim 9, wherein the battery device is used to supply power to the electrical device.

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