Battery monomer, battery device and power utilization device

Abstract

The utility model discloses a battery monomer, a battery device and a power utilization device. The single battery comprises an electrode assembly formed by winding or laminating a battery pole piece, the battery pole piece comprises a main body part and a tab part, the tab part is led out from the end part of the main body part, the tab part is provided with a first end and a second end, the first end is connected with the main body part, and the second end is positioned at one end, far away from the main body part, of the tab part; wherein the first end is provided with a first fillet, the second end is provided with a second fillet, and a first radius corresponding to the first fillet is smaller than a second radius corresponding to the second fillet. Therefore, the first end, connected with the main body part, of the tab part is provided with the first round corner, the second end, away from the main body part, of the tab part is provided with the second round corner, the first radius corresponding to the first round corner is smaller than the second radius corresponding to the second round corner, the situation that the tab part is greatly turned over relative to the main body part can be improved, and then the risk that the tab part is broken is relieved.

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] Energy saving and emission reduction is the key to sustainable development, which promotes the adjustment of energy structure and the development and application of battery technology. The key to the development of battery technology lies in electrochemical energy storage technology, which has been widely used in portable electronics, electric vehicles and energy storage systems due to its high energy density, good cycle ability, high working voltage, environmental protection and low self-discharge.

[0003] The electrode assembly is an important part of the battery, and the electrode assembly includes a battery pole piece. The battery pole piece needs to be die-cut during the manufacturing process to form a tab part. However, the existing design of the tab part has a high risk of tab part collapse, which can easily cause the tab part to tear. UTILITY MODEL CONTENT

[0004] The main purpose of the present application is to provide a battery monomer, a battery device and a power utilization device, which aims to solve the above technical problems existing in the prior art.

[0005] To solve the above problems, the present application provides a battery monomer, which comprises an electrode assembly formed by winding or stacking a battery pole piece, the battery pole piece comprising a main body part and a tab part, the tab part being led out from an end of the main body part, the tab part having a first end and a second end, the first end being connected to the main body part, and the second end being located at an end of the tab part away from the main body part; wherein the first end has a first fillet, and the second end has a second fillet, the first radius corresponding to the first fillet being smaller than the second radius corresponding to the second fillet. Thus, the first end of the tab part connected to the main body part has a first fillet, and the second end away from the main body part has a second fillet, the first radius corresponding to the first fillet being smaller than the second radius corresponding to the second fillet, which can improve the large amplitude folding of the tab part relative to the main body part, and further alleviate the risk of tab part fracture.

[0006] In some embodiments, the number of first fillets is two, and the two first fillets are located on both sides of the first end in a vertical direction, the vertical direction being perpendicular to the interval direction of the first end and the second end. Thus, by providing two first fillets and locating the two first fillets on both sides of the first end in a vertical direction, the large amplitude folding of the tab part relative to the main body part can be further improved, and the risk of tab part fracture can be further alleviated.

[0007] In some embodiments, the number of the second rounded corners is two, and the two second rounded corners are located on two sides of the second end in a vertical direction, the vertical direction being perpendicular to a direction of interval between the first end and the second end. In this way, by arranging two second rounded corners and locating the two second rounded corners on two sides of the second end in a vertical direction, the risk of the tab part being folded by a large amplitude relative to the main body part can be further improved, and the risk of the tab part being broken can be further relieved.

[0008] In some embodiments, the center of the first rounded corner corresponding circle is located outside the tab part, and the center of the second rounded corner corresponding circle is located inside the tab part. In this way, by locating the center of the first rounded corner corresponding circle outside the tab part and locating the center of the second rounded corner corresponding circle inside the tab part, the size of the tab part can be rationalized, the risk of the tab part being folded by a large amplitude relative to the main body part can be further improved, and the risk of the tab part being broken can be further relieved.

[0009] In some embodiments, the battery pole piece comprises an insulating layer, and the insulating layer is at least partially covered on the connection between the first end and the main body part. In this way, by arranging the insulating layer, the risk of the battery pole piece being short-circuited after being wound to form an electrode assembly can be relieved by the insulating layer.

[0010] In some embodiments, the ratio of the second radius to the first radius is greater than 1 and less than or equal to 7. In this way, by making the ratio of the second radius to the first radius greater than 1 and less than or equal to 7, the risk of the tab part being folded by a large amplitude relative to the main body part can be further improved, and the risk of the tab part being broken can be further relieved.

[0011] In some embodiments, the first radius is greater than or equal to 1 mm and less than or equal to 16 mm, and / or the second radius is greater than 1 mm and less than or equal to 24 mm. In this way, the risk of the tab part and the main body part being insufficiently supported due to the first radius being too large and / or the second radius being too small, so that the tab part is folded by a large amplitude relative to the main body part, and the risk of the tab part being broken due to the first radius being too small can be relieved.

[0012] In some embodiments, the first central angle corresponding to the first rounded corner and / or the second central angle corresponding to the second rounded corner is greater than or equal to 20° and less than or equal to 150°. In this way, by making the first central angle corresponding to the first rounded corner and / or the second central angle corresponding to the second rounded corner greater than or equal to 20° and less than or equal to 150°, the risk of the tab part being broken due to the first central angle and / or the second central angle being too large, and the risk of the tab part being folded by a large amplitude relative to the main body part due to the first central angle and / or the second central angle being too small can be relieved.

[0013] In some embodiments, the first radius is greater than or equal to 2mm to 4mm, the second radius is greater than or equal to 15mm and less than or equal to 16mm, the first fillet corresponds to a first central angle greater than or equal to 85° and less than or equal to 95°, and the second fillet corresponds to a second central angle greater than or equal to 55° and less than or equal to 60°. In this way, by precisely limiting the size of the first radius, the second radius, the first central angle, and the second central angle, the large amplitude folding of the tab portion relative to the main body portion can be further improved, thereby alleviating the risk of the tab portion being broken.

[0014] In some embodiments, the first radius is greater than or equal to 2mm to 4mm, the second radius is greater than or equal to 15mm and less than or equal to 16mm, the first fillet corresponds to a first central angle greater than or equal to 25° and less than or equal to 35°, and the second fillet corresponds to a second central angle greater than or equal to 55° and less than or equal to 60°. In this way, by precisely limiting the size of the first radius, the second radius, the first central angle, and the second central angle, the large amplitude folding of the tab portion relative to the main body portion can be further improved, thereby alleviating the risk of the tab portion being broken.

[0015] In some embodiments, the first radius is greater than or equal to 3mm to 5mm, the second radius is greater than 3mm and less than or equal to 5mm, the first fillet corresponds to a first central angle greater than or equal to 25° and less than or equal to 35°, and the second fillet corresponds to a second central angle greater than or equal to 55° and less than or equal to 60°. In this way, by precisely limiting the size of the first radius, the second radius, the first central angle, and the second central angle, the large amplitude folding of the tab portion relative to the main body portion can be further improved, thereby alleviating the risk of the tab portion being broken.

[0016] In some embodiments, the number of the tab portions is a plurality, each of the tab portions is connected to the main body portion, and the plurality of the tab portions are arranged in a vertical direction perpendicular to the interval direction between the first end and the second end. In this way, by arranging the plurality of the tab portions in the vertical direction, the tab portions can be conveniently wound to form an electrode assembly.

[0017] To solve the above problems, the application provides a battery device, which comprises the battery cell as described above.

[0018] To solve the above problems, the application provides a power consumption device, which comprises the battery device as described above. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative effort.

[0020] Figure 1 is a structural schematic diagram of a vehicle according to one or more embodiments of the present application;

[0021] Figure 2 is an exploded structural schematic diagram of a battery device according to one or more embodiments of the present application;

[0022] Figure 3 is an exploded structural schematic diagram of a battery cell according to one or more embodiments of the present application;

[0023] Figure 4 is a structural schematic diagram of a battery pole piece according to one or more embodiments of the present application;

[0024] Figure 5 is Figure 4 is an embodiment structural schematic diagram of a tab part of the battery pole piece shown.

[0025] Reference signs: 1, vehicle; 2, battery device; 3, controller; 4, motor; 20, box body; 21, first part; 22, second part; 10, battery cell; 100, electrode assembly; 200, end cover; 300, shell; 400, housing; 110, battery pole piece; 111, main body part; 112, tab part; 113, insulation layer; 114, first end; 115, second end; 1121, first round corner; 1122, second round corner; R1, first radius; R2, second radius; A1, first central angle; O, center; A2, second central angle; X, vertical direction; Y, spacing direction. DETAILED DESCRIPTION

[0026] The embodiments of the technical solutions of the present application will be described in detail below with reference to the 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.

[0027] 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.

[0028] In the description of the embodiments of the present application, the technical terms "first", "second" and the like 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 "multiple" is more than two, unless otherwise explicitly specified and limited.

[0029] In this paper, the term "embodiment" means that the specific features, structures or properties described in conjunction with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0030] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which means that there are 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 in an "or" relationship.

[0031] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0032] 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 indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0033] 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 mechanical connection, or it can be electrical connection; 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 meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0034] At present, from the development of market situation, the application of battery is more and more widely. The battery is not only applied to the energy storage power system of hydropower, thermal power, wind power and solar power station, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric vehicles, electric transportation tools, military equipment and aerospace and other fields. With the continuous expansion of the application field of battery, the demand of its market is also increasing.

[0035] The battery mentioned in the art can be divided into primary battery and rechargeable battery according to whether it can be charged. The primary battery is also called "disposable" battery and primary cell, because it cannot be charged for use after its power is consumed, and can only be discarded. The rechargeable battery is also called secondary battery or secondary cell, storage battery. The manufacturing materials and process of rechargeable battery are different from those of primary battery, and its advantage is that it can be used repeatedly after charging. The output current load of rechargeable battery is higher than that of most primary batteries. The common types of rechargeable batteries at present are: lead-acid battery, nickel-hydrogen battery and lithium-ion battery. Lithium-ion battery has the advantages of light weight, large capacity (the capacity is 1.5 times to 2 times of the same weight of nickel-hydrogen battery), no memory effect and very low self-discharge rate, so even if the price is relatively high, it is still widely used. Lithium-ion battery is also widely used in pure electric vehicles and hybrid electric vehicles. The capacity of lithium-ion battery used for such purpose is relatively low, but it has high output, charging current and long service life, but the cost is high.

[0036] The battery described in the embodiments of the present application refers to a rechargeable battery or a primary battery. Hereinafter, the embodiments of the present application will be mainly described taking lithium-ion battery as an example. It should be understood that the embodiments of the present application are applicable to any other appropriate type of rechargeable battery. The battery mentioned in the embodiments disclosed in the present application can be directly or indirectly applied to appropriate devices to power the devices.

[0037] The present application provides a power consuming device, which can include but is not limited to mobile phones, tablets, notebook computers, electric toys, power tools, electric vehicles, electric vehicles, ships, spacecraft and the like. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric plane toys, etc. Spacecraft can include airplanes, rockets, space shuttles and spacecraft, etc. Among them, the power consuming device can include a battery, and the power consuming device can provide electric energy through the battery to realize the corresponding function.

[0038] The present application also provides an electric vehicle, which can include a battery device.

[0039] Please refer toFigure 1 , Figure 1 is a structural schematic diagram of a vehicle according to one or more embodiments of the present application.

[0040] The vehicle 1 can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid automobile, or a range extended automobile, etc. The vehicle 1 is internally provided with a battery device 2, which can be arranged at the bottom, the head, or the tail of the vehicle 1. The battery device 2 can be used for power supply of the vehicle 1, for example, the battery device 2 can be used as an operating power source of the vehicle 1. The vehicle 1 can further include a controller 3 and a motor 4, and the controller 3 is used to control the battery device 2 to supply power to the motor 4, for example, to meet the power demand of the vehicle 1 during starting, navigation, and driving.

[0041] In some embodiments of the present application, the battery device 2 can not only be used as an operating power source of the vehicle 1, but also be used as a driving power source of the vehicle 1, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1.

[0042] In order to improve the performance of the power consuming device, the present application further provides a battery device, which is described with reference to Figure 2 , Figure 2 is an exploded structural schematic diagram of a battery device according to one or more embodiments of the present application.

[0043] The shape of the battery device 2 can include but is not limited to a square cylinder or any other shape.

[0044] In some embodiments, the battery device 2 can include a box body 20 and a battery cell 10, and the battery cell 10 is accommodated in the box body 20. The box body 20 is used to provide an accommodation space for the battery cell 10, and the box body 20 can adopt various structures. In some embodiments, the box body 20 can include a first part 21 and a second part 22, and the first part 21 and the second part 22 are mutually covered. The first part 21 and the second part 22 jointly define an accommodation space for accommodating the battery cell 10. The second part 22 can be a hollow structure with one end open, and the first part 21 can be a plate structure, which is covered on the open side of the second part 22 to jointly define the accommodation space with the second part 22. The first part 21 and the second part 22 can also be hollow structures with one side open, and the open side of the first part 21 is covered on the open side of the second part 22.

[0045] In the battery device 2, the battery cells 10 can be multiple, and the multiple battery cells 10 can be connected in series or in parallel or in a mixed manner. The mixed manner means that the multiple battery cells 10 are connected in series and in parallel. The multiple battery cells 10 can be directly connected in series or in parallel or in a mixed manner, and the whole of the multiple battery cells 10 is accommodated in the case 20. Of course, the battery device 2 can be that the multiple battery cells 10 are connected in series or in parallel or in a mixed manner to form a battery module, and the multiple battery modules are connected in series or in parallel or in a mixed manner to form a whole, and the whole is accommodated in the case 20. The battery device 2 can further include other structures, for example, the battery device 2 can further include a current collecting member for realizing the electrical connection between the multiple battery cells 10.

[0046] The manufacturing method of the battery cell 10 includes a laminated type and a winding type, that is, the battery cell 10 is divided into a laminated battery and a winding battery. The laminated battery has uniform current collecting effect, small internal resistance, and large specific power. However, in order to improve the precision, the mold precision is required to be very high, the equipment investment is high, and the process is relatively complex, and the production efficiency is low. The winding battery is simple to manufacture, and the manufacturing and assembling processes generally require equipment precision, has high production efficiency, and low cost. In terms of performance, the winding battery has excellent high and low temperature performance, very fast charging, super long life, stable high output voltage, and strong structure and shock resistance.

[0047] Referring to Figure 3 , Figure 3 is a schematic diagram of the exploded structure of the battery cell according to one or more embodiments of the present application.

[0048] The battery cell 10 refers to the smallest unit constituting the battery device 2. The battery cell 10 can include a housing 400, an electrode assembly 100, and other functional components, and the housing 400 includes an end cap 200 and a case 300.

[0049] The end cover 200 refers to a component that covers the opening of the housing 300 to isolate the internal environment of the battery cell 10 from the external environment. Without limitation, the shape of the end cover 200 can be adapted to the shape of the housing 300 to fit the housing 300. Optionally, the end cover 200 can be made of a material with certain hardness and strength, such as aluminum alloy, so that the end cover 200 is not easily deformed when subjected to extrusion collision, so that the battery cell 10 can have higher structural strength, and the safety performance can also be improved. The end cover 200 can be provided with functional components such as electrode terminals. The electrode terminals can be used to electrically connect with the electrode assembly 100 for outputting or inputting the electrical energy of the battery cell 10. In some embodiments, the electrode terminals can include poles. The poles can include positive poles and negative poles for output of current and connection with external circuits. In some embodiments, the end cover 200 can also be provided with a pressure relief device for relieving internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold value. The material of the end cover 200 can also be various, such as the material of the end cover 200 including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, an insulating member can also be provided on the inner side of the end cover 200, which can be used to isolate the electrical connection components in the housing 300 from the end cover 200 to reduce the risk of short circuit. For example, the insulating member can be plastic, rubber, etc.

[0050] The housing 300 is a component for fitting the end cover 200 to form the internal environment of the battery cell 10, wherein the formed internal environment can be used to accommodate the electrode assembly 100, the electrolyte and other components. The housing 300 and the end cover 200 can be independent components, and an opening can be provided on the housing 300, and the end cover 200 is covered on the opening to form the internal environment of the battery cell 10. Without limitation, the end cover 200 and the housing 300 can also be integrated, specifically, the end cover 200 and the housing 300 can form a common connecting surface before other components enter the housing, and when it is necessary to seal the inside of the housing 300, the end cover 200 is covered on the housing 300. The housing 300 can be various shapes and various sizes, such as rectangular, cylindrical, hexagonal, etc. Specifically, the shape of the housing 300 can be determined according to the specific shape and size of the electrode assembly 100. The material of the housing 300 can be various, such as the material of the housing 300 including but not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0051] The electrode assembly 100 is a component in which electrochemical reactions occur in the battery cell 10. One or more electrode assemblies 100 can be contained within the case 300. The electrode assembly 100 is mainly formed by winding or layering a positive electrode sheet and a negative electrode sheet, and an insulator is generally provided between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have portions with active materials that constitute a main body of the electrode assembly 100, and portions without active materials that each constitute a tab portion. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or at opposite ends of the main body. During charging and discharging of the battery, the positive electrode active material and the negative electrode active material react with an electrolyte, and the tab portions are connected to electrode terminals to form a current loop.

[0052] In some embodiments, the electrode assembly 100 includes a positive electrode, a negative electrode, and an insulator. During charging and discharging of the battery cell 10, active ions (e.g., lithium ions) are intercalated and deintercalated between the positive electrode and the negative electrode. The insulator is provided between the positive electrode and the negative electrode, and can function to prevent short-circuiting of the positive and negative electrodes while allowing the active ions to pass through.

[0053] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material provided on at least one surface of the positive electrode current collector.

[0054] As an example, the positive electrode current collector has two surfaces opposite in the thickness direction thereof, and the positive electrode active material is provided on either or both of the two opposite surfaces of the positive electrode current collector.

[0055] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, silver surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium, or the like can be used. The composite current collector can include a high molecular material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, or the like) on a high molecular material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, or the like).

[0056] As an example, the positive electrode active material can include at least one of lithium-containing phosphates, lithium transition metal oxides, and modified compounds thereof, and other conventional materials that can be used as a battery positive electrode active material can also be used. These positive electrode active materials can be used alone only one or two or more can be used in combination. Among them, examples of the lithium-containing phosphates can include, but are not limited to, at least one of lithium iron phosphate, a composite of lithium iron phosphate and carbon, lithium manganese phosphate, a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite of lithium manganese iron phosphate and carbon. Examples of the lithium transition metal oxides can include, but are not limited to, at least one of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and modified compounds thereof.

[0057] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0058] As an example, the negative electrode current collector can employ a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, silver surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, or the like can be employed. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0059] As an example, the negative electrode sheet can include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0060] As an example, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode active material is disposed on either one or both of the two opposite surfaces of the negative electrode current collector.

[0061] As an example, the negative electrode active material can employ a negative electrode active material for a battery cell 10 known in the art. As an example, the negative electrode active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy, and other conventional materials that can be used as a battery negative electrode active material can also be used. These negative electrode active materials can be used alone only one or two or more can be used in combination.

[0062] In some embodiments, the material of the positive current collector can be aluminum and the material of the negative current collector can be copper.

[0063] In some embodiments, the separator is a separator membrane. The separator membrane can be any porous structure separator membrane known to have good chemical stability and mechanical stability.

[0064] For example, the main material of the separator membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator membrane can be a single layer film or a multi-layer composite film. When the separator membrane is a multi-layer composite film, the materials of the layers can be the same or different. The separator can be a separate component between the positive and negative electrodes or can be attached to the surface of the positive and negative electrodes.

[0065] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive and negative electrodes and functions to transport ions and separate the positive and negative electrodes.

[0066] In some embodiments, the battery cell 10 further includes an electrolyte that functions to conduct ions between the positive and negative electrodes. The electrolyte can be in a liquid state, a gel state, or a solid state.

[0067] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0068] In some embodiments, the electrolyte salt can be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonylimide, lithium bis-trifluoromethanesulfonylimide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro oxalate borate, lithium bisoxalate borate, lithium difluoro bisoxalate phosphate, and lithium tetrafluoro oxalate phosphate.

[0069] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, butanedisulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be an ether solvent. The ether solvent can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ether.

[0070] In some embodiments, the gel-state electrolyte includes a polymer as a backbone network of the electrolyte, in combination with an ionic liquid-lithium salt.

[0071] In some embodiments, the solid-state electrolyte includes a polymer solid-state electrolyte, an inorganic solid-state electrolyte, or a composite solid-state electrolyte.

[0072] As an example, the polymer solid electrolyte can be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single-ion polymer, poly ionic liquid-lithium salt, cellulose, etc.

[0073] As an example, the inorganic solid electrolyte can be one or more of oxide solid electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON film), sulfide solid electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorus sulfur, sulfide silver germanite), amorphous sulfide), halide solid electrolyte, nitride solid electrolyte and hydride solid electrolyte.

[0074] As an example, the composite solid electrolyte is formed by adding inorganic solid electrolyte fillers to the polymer solid electrolyte.

[0075] However, the positive and / or negative electrode sheet needs to be subjected to die cutting treatment to form the tab portion during the manufacturing process, but the existing design of the tab portion has a high risk of tab portion falling off, which is easy to cause the tab portion to tear, etc.

[0076] Referring to Figure 4 and Figure 5 , Figure 4 is a structural schematic diagram of a battery electrode sheet according to one or more embodiments of the present application. Figure 5 is Figure 4 is an embodiment structure schematic diagram of the tab portion of the battery electrode sheet shown in

[0077] The battery electrode sheet 110 can be used for winding or stacking to form an electrode assembly 100, the battery electrode sheet 110 includes a main body portion 111 and a tab portion 112, the tab portion 112 is led out from an end of the main body portion 111, the tab portion 112 has a first end 114 and a second end 115, the first end 114 is connected with the main body portion 111, and the second end 115 is located at an end of the tab portion 112 away from the main body portion 111; wherein the first end 114 has a first round corner 1121, and the second end 115 has a second round corner 1122, a first radius R1 corresponding to the first round corner 1121 is smaller than a second radius R2 corresponding to the second round corner 1122.

[0078] The battery pole piece 110 can be a positive pole piece or a negative pole piece, and the main body 111 can be a negative current collector or a positive current collector, which can be used to coat an active material. The main body 111 can have a length direction and a width direction perpendicular to each other, the battery pole piece 110 can be wound along the length direction of the main body 111 to form an electrode assembly 100, and the tab portion 112 of the battery tab can be connected with the end portion of the main body 111 in the width direction of the main body 111. Specifically, the tab portion 112 has a first end 114 and a second end 115, which can be two ends of the tab portion 112 in the width direction of the main body 111, respectively, the first end 114 is fixed with the main body 111, and in an ideal state, the tab portion 112 and the main body 111 are smoothly connected, that is, there is no bending phenomenon at the connection between the first end 114 and the main body 111. In order to improve the bending phenomenon of the tab portion 112 relative to the main body 111, a first fillet 1121 is formed at the first end 114, and a second fillet 1122 is formed at the second end 115, the first end 114 can be connected with the main body 111 through the first fillet 1121, and the connection between the main body 111 and the first fillet 1121 can be smoothly connected, the first fillet 1121 and the second fillet 1122 can correspond to a circle, the first radius R1 of the first fillet 1121 corresponding to the circle is smaller than the second radius R2 of the second fillet 1122 corresponding to the circle, that is, when the central angles corresponding to the first fillet 1121 and the second fillet 1122 are substantially the same, the arc length of the first fillet 1121 is smaller than the arc length of the second fillet 1122, thereby increasing the support force of the first end 114 of the tab portion 112 and reducing the gravity of the edge of the second end 115, to improve the problem of the tab portion 112 falling off.

[0079] Through the above embodiment, the first end 114 of the tab portion 112 connected with the main body 111 has the first fillet 1121, and the second end 115 away from the main body 111 has the second fillet 1122, the first radius R1 corresponding to the first fillet 1121 is smaller than the second radius R2 corresponding to the second fillet 1122, which can improve the large amplitude folding of the tab portion 112 relative to the main body 111, and thereby relieve the risk of fracture of the tab portion 112.

[0080] In some embodiments, the center O of the first rounded corner 1121 corresponds to a circle located outside the tab portion 112, and the center O of the second rounded corner 1122 corresponds to a circle located inside the tab portion 112. The center O of the first rounded corner 1121 is located outside the tab portion 112, that is, the first rounded corner 1121 is a concave rounded corner, and the center O of the second rounded corner 1122 is located on the tab portion 112, that is, the second rounded corner 1122 is a convex rounded corner, so that the size of the tab portion 112 can be reasonably optimized, and the risk of the tab portion 112 being broken can be further reduced.

[0081] In some embodiments, the number of the first rounded corners 1121 is two, and the two first rounded corners 1121 are located on both sides of the first end 114 in the vertical direction X, which is perpendicular to the interval direction Y between the first end 114 and the second end 115. The interval direction Y between the first end 114 and the second end 115 can be the width direction of the main body portion 111, and the vertical direction X can be the length direction of the main body portion 111. The two first rounded corners 1121 can be symmetrically arranged along the center line of the tab portion 112, and the two first rounded corners 1121 are located on both sides of the first end 114 in the vertical direction X, so that the support of the first end 114 of the tab portion 112 can be further improved, and the risk of the tab portion 112 being broken can be further reduced.

[0082] In some embodiments, the number of the second rounded corners 1122 is two, and the two second rounded corners 1122 are located on both sides of the second end 115 in the vertical direction X, which is perpendicular to the interval direction Y between the first end 114 and the second end 115. The interval direction Y between the first end 114 and the second end 115 can be the width direction of the main body portion 111, and the vertical direction X can be the length direction of the main body portion 111. The two second rounded corners 1122 can be symmetrically arranged along the center line of the tab portion 112, and the two second rounded corners 1122 are located on both sides of the second end 115 in the vertical direction X, so that the gravity of the edge of the second end 115 can be further reduced, and the risk of the tab portion 112 being broken can be further reduced.

[0083] In some embodiments, the battery tab 110 includes an insulating layer 113 covering at least partially the junction of the first end 114 and the main body 111. The insulating layer 113 can be made of a polymer, inorganic oxide particles, or a mixture of both. Specifically, the insulating layer 113 is an insulating glue, such as at least one of an oil-based epoxy resin, a bismaleimide resin, a water-based polyvinylidene fluoride, a polyimide. Alternatively, the insulating layer 113 can also be an insulating paint or material, such as a metal oxide particle coating, which is made of a composition including metal oxide particles, polyvinylidene fluoride, and N-methyl pyrrolidone, and the metal oxide particles can be made of aluminum oxide, titanium dioxide, zinc oxide, magnesium oxide, or a combination thereof. The insulating layer 113 can cover the surface of the junction of the main body 111 and the tab portion 112, i.e., the insulating layer 113 covers at least partially the root of the main body 111, which can alleviate the risk of short circuit of the battery tab 110 after the battery tab 110 is wound to form the electrode assembly 100. Meanwhile, the design of the first and second rounded corners 1121 and 1122 can improve the risk of the insulating layer 113 reducing the support of the first end 114 of the tab portion 112.

[0084] In some embodiments, the ratio of the second radius R2 to the first radius R1 is greater than 1 and less than or equal to 7. The ratio of the second radius R2 to the first radius R1 can be greater than 1 and less than or equal to 5, or the ratio of the second radius R2 to the first radius R1 can be greater than 1 and less than or equal to 3, or the ratio of the second radius R2 to the first radius R1 can be greater than or equal to 2 and less than or equal to 5, or the ratio of the second radius R2 to the first radius R1 can be greater than or equal to 3 and less than or equal to 6, or the ratio of the second radius R2 to the first radius R1 can be equal to 2, 3, 4, 5, 6, or the like, which can further improve the folding of the tab portion 112 relative to the main body 111 to a larger extent, thereby alleviating the risk of the tab portion 112 being broken.

[0085] In some embodiments, the first radius R1 is greater than or equal to 1 mm and less than or equal to 16 mm. The first radius R1 can be greater than or equal to 1 mm and less than or equal to 10 mm, or the first radius R1 can be greater than or equal to 1 mm and less than or equal to 5 mm, or the first radius R1 can be greater than or equal to 5 mm and less than or equal to 16 mm, or the first radius R1 can be greater than or equal to 10 mm and less than or equal to 16 mm, or the first radius R1 can be 1 mm, 3 mm, 5 mm, 7 mm, 9 mm, 11 mm, 13 mm, 15 mm, or the like.

[0086] And / or, the second radius R2 is greater than 1 mm and less than or equal to 24 mm, the second radius R2 can be greater than 1 mm and less than or equal to 20 mm, or the second radius R2 is greater than 1 mm and less than or equal to 15 mm, or the second radius R2 is greater than or equal to 5 mm and less than or equal to 20 mm, or the first radius R1 is greater than or equal to 8 mm and less than or equal to 16 mm, in particular, the first radius R1 can be 3 mm, 5 mm, 7 mm, 9 mm, 11 mm, 13 mm, 15 mm, 20 mm, 23 mm or 23 mm, etc. In this way, the risk of the tab portion 112 being folded relative to the body portion 111 at a large amplitude due to the first radius R1 being too large and / or the second radius R2 being too small, and the risk of the tab portion 112 being broken due to the first radius R1 being too small, can be alleviated, and the support force between the tab portion 112 and the body portion 111 can be improved.

[0087] In some embodiments, the first circular angle A1 corresponding to the first rounded corner 1121 and / or the second circular angle A2 corresponding to the second rounded corner 1122 is greater than or equal to 20° and less than or equal to 150°. The first circular angle A1 corresponding to the first rounded corner 1121 can be greater than or equal to 30° and less than or equal to 120°, the first circular angle A1 corresponding to the first rounded corner 1121 can be greater than or equal to 60° and less than or equal to 120°, the first circular angle A1 corresponding to the first rounded corner 1121 can be greater than or equal to 60° and less than or equal to 90°, or the first circular angle A1 corresponding to the first rounded corner 1121 can be greater than or equal to 30° and less than or equal to 90°, in particular, the first circular angle A1 corresponding to the first rounded corner 1121 can be 30°, 45°, 60°, 90°, 120° or 150°.

[0088] And / or, the second circular angle A2 corresponding to the second rounded corner 1122 is greater than or equal to 20° and less than or equal to 150°. The second circular angle A2 corresponding to the second rounded corner 1122 can be greater than or equal to 30° and less than or equal to 120°, the second circular angle A2 corresponding to the second rounded corner 1122 can be greater than or equal to 60° and less than or equal to 120°, the second circular angle A2 corresponding to the second rounded corner 1122 can be greater than or equal to 60° and less than or equal to 90°, or the second circular angle A2 corresponding to the second rounded corner 1122 can be greater than or equal to 30° and less than or equal to 90°, in particular, the second circular angle A2 corresponding to the second rounded corner 1122 can be 30°, 45°, 60°, 90°, 120° or 150°. The risk of the tab portion 112 being broken due to the first circular angle A1 and / or the second circular angle A2 being too large, and the risk of the tab portion 112 being folded relative to the body portion 111 at a large amplitude due to the first circular angle A1 and / or the second circular angle A2 being too small, can be alleviated.

[0089] Specifically, the first radius R1 is greater than or equal to 2mm to 4mm, the second radius R2 is greater than or equal to 15mm and less than or equal to 16mm, the first circular corner 1121 corresponds to a first circular central angle A1 greater than or equal to 85° and less than or equal to 95°, and the second circular corner 1122 corresponds to a second circular central angle A2 greater than or equal to 55° and less than or equal to 60°. In this embodiment, the first radius R1 can be 2mm, 3mm or 4mm, etc., the second radius R2 can be 15mm, 15.5mm, 16mm, etc., the first circular corner 1121 corresponds to a first circular central angle A1 of 85°, 90°, or 95°, etc., and the second circular corner 1122 corresponds to a second circular central angle A2 greater than or equal to 55°, 57° or 60°, etc. In this way, by precisely limiting the sizes of the first radius R1, the second radius R2, the first circular central angle A1 and the second circular central angle A2, the risk of the tab portion 112 being folded relative to the main body portion 111 by a large amplitude can be further improved, and the risk of the tab portion 112 being broken can be further alleviated.

[0090] Specifically, the first radius R1 is greater than or equal to 2mm to 4mm, the second radius R2 is greater than or equal to 15mm and less than or equal to 16mm, the first circular corner 1121 corresponds to a first circular central angle A1 greater than or equal to 25° and less than or equal to 35°, and the second circular corner 1122 corresponds to a second circular central angle A2 greater than or equal to 55° and less than or equal to 60°. In this embodiment, the first radius R1 can be 2mm, 3mm or 4mm, etc., the second radius R2 can be 15mm, 15.5mm, 16mm, etc., the first circular corner 1121 corresponds to a first circular central angle A1 of 25°, 30°, or 35°, etc., and the second circular corner 1122 corresponds to a second circular central angle A2 greater than or equal to 55°, 57° or 60°, etc. In this way, by precisely limiting the sizes of the first radius R1, the second radius R2, the first circular central angle A1 and the second circular central angle A2, the risk of the tab portion 112 being folded relative to the main body portion 111 by a large amplitude can be further improved, and the risk of the tab portion 112 being broken can be further alleviated.

[0091] Specifically, the first radius R1 is greater than or equal to 3 mm to 5 mm, the second radius R2 is greater than 3 mm and less than or equal to 5 mm, the first fillet 1121 corresponds to a first central angle A1 greater than or equal to 25° and less than or equal to 35°, and the second fillet 1122 corresponds to a second central angle A2 greater than or equal to 55° and less than or equal to 60°. In the embodiment, the first radius R1 can be 2 mm, 3 mm, or 4 mm, etc., the second radius R2 can be 4 mm, 4.5 mm, 5 mm, etc., the first fillet 1121 corresponds to a first central angle A1 of 25°, 30°, or 35°, etc., and the second fillet 1122 corresponds to a second central angle A2 greater than or equal to 55°, 57°, or 60°, etc. In this way, by accurately limiting the sizes of the first radius R1, the second radius R2, the first central angle A1, and the second central angle A2, the risk of the tab portion 112 being broken can be further alleviated.

[0092] In some embodiments, the number of the tab portions 112 is a plurality, each of the tab portions 112 is connected with the body portion 111, and the plurality of tab portions 112 are arranged at intervals along the vertical direction X perpendicular to the interval direction Y of the first end 114 and the second end 115. The plurality of tab portions 112 arranged at intervals along the vertical direction X can be correspondingly and laminatedly arranged to jointly communicate the electrode tabs of the electrode assembly 100 when the battery tab 110 is wound to form the electrode assembly 100, so as to facilitate welding with the adapter tab through the electrode tabs.

[0093] In summary, the first end 114 of the tab portion 112 connected with the body portion 111 has the first fillet 1121, and the second end 115 away from the body portion 111 has the second fillet 1122, the first radius R1 corresponding to the first fillet 1121 is less than the second radius R2 corresponding to the second fillet 1122, which can improve the risk of the tab portion 112 being broken.

[0094] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced equivalently. Such modifications or replacements do not change the essence of the corresponding technical solutions, which should be covered in the scope of the present application. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present 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, characterized by, The battery cell comprises an electrode assembly formed by winding or stacking battery electrode sheets, the battery electrode sheets comprising: a body portion; a tab portion leading out from an end of the body portion, the tab portion having a first end connected to the body portion and a second end located at an end of the tab portion away from the body portion; wherein the first end has a first rounded corner and the second end has a second rounded corner, a first radius of a circle corresponding to the first rounded corner being smaller than a second radius of a circle corresponding to the second rounded corner.

2. The battery cell of claim 1, wherein, The number of the first rounded corners is two, the two first rounded corners being located on two sides of the first end in a vertical direction perpendicular to a direction of separation between the first end and the second end.

3. The battery cell of claim 1, wherein, The number of the second rounded corners is two, the two second rounded corners being located on two sides of the second end in a vertical direction perpendicular to the direction of separation between the first end and the second end.

4. The battery cell according to any one of claims 1 to 3, characterized in that, Centers of the circles corresponding to the first rounded corners are located outside the tab portion, and centers of the circles corresponding to the second rounded corners are located inside the tab portion.

5. The battery cell according to any one of claims 1 to 4, characterized in that, The battery electrode sheets comprise an insulating layer at least partially covering a connection between the first end and the body portion.

6. The battery cell according to any one of claims 1 to 5, characterized in that, The ratio of the second radius to the first radius is greater than 1 and less than or equal to 7.

7. The battery cell according to any one of claims 1 to 6, characterized in that The first radius is greater than or equal to 1 mm and less than or equal to 16 mm, and / or the second radius is greater than 1 mm and less than or equal to 24 mm.

8. The battery cell according to any one of claims 1 to 7, characterized in that A first central angle corresponding to the first rounded corner and / or a second central angle corresponding to the second rounded corner is greater than or equal to 20° and less than or equal to 150°.

9. The battery cell according to any one of claims 1 to 8, characterized in that The first radius is greater than or equal to 2 mm to 4 mm, the second radius is greater than or equal to 15 mm and less than or equal to 16 mm, the first central angle corresponding to the first rounded corner is greater than or equal to 85° and less than or equal to 95°, and the second central angle corresponding to the second rounded corner is greater than or equal to 55° and less than or equal to 60°.

10. The battery cell according to any one of claims 1 to 8, characterized in that The first radius is greater than or equal to 2 mm to 4 mm, the second radius is greater than or equal to 15 mm and less than or equal to 16 mm, the first central angle corresponding to the first rounded corner is greater than or equal to 25° and less than or equal to 35°, and the second central angle corresponding to the second rounded corner is greater than or equal to 55° and less than or equal to 60°.

11. The battery cell according to any one of claims 1 to 8, characterized in that The first radius is greater than or equal to 3 mm to 5 mm, the second radius is greater than 3 mm and less than or equal to 5 mm, the first central angle corresponding to the first rounded corner is greater than or equal to 25° and less than or equal to 35°, and the second central angle corresponding to the second rounded corner is greater than or equal to 55° and less than or equal to 60°.

12. The battery cell according to any one of claims 1 to 11, characterized in that The number of the tab portions is multiple, each of the tab portions being connected to the body portion, and the multiple tab portions being arranged in a vertical direction perpendicular to the direction of separation between the first end and the second end.

13. A battery device characterized by comprising: The battery device comprises the battery cell according to any one of claims 1 to 12.

14. An electrical device, comprising: The electric device comprises the battery device according to claim 13.

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