Battery monomer, battery device and electric device

Abstract

The utility model provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a shell and an electrode assembly, the electrode assembly is accommodated in the shell, the electrode assembly comprises a pole piece and a separator which are overlapped with each other, the pole piece comprises a current collector and active material layers arranged on the two sides of the current collector in the thickness direction, the current collector comprises a base body and a reinforcing bulge, and the reinforcing bulge is arranged on the base body. The reinforcing protrusions are arranged on at least one side of the base body in the thickness direction, so that the strength and rigidity of the current collector are improved, the non-deformability of the pole piece is enhanced, the problem of wrinkles of the pole piece is solved, and the performance of the battery monomer is improved.

Description

Technical Field

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

[0002] Batteries are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools, etc.

[0003] During the operation of a battery cell, its electrodes are prone to wrinkling, which leads to a decrease in the performance of the battery cell. Utility Model Content

[0004] In view of the above problems, this application provides a battery cell, a battery device, and an electrical device that can improve the problem of electrode wrinkles and enhance the performance of the battery cell.

[0005] In a first aspect, this application provides a battery cell, comprising: a housing; an electrode assembly housed within the housing, the electrode assembly comprising stacked electrodes and separators, the electrodes comprising current collectors and active material layers, the active material layers being disposed on both sides of the current collectors in their thickness direction, wherein the current collector comprises a substrate and reinforcing protrusions, the reinforcing protrusions being disposed on at least one side of the substrates in their thickness direction.

[0006] In the embodiments of this application, the battery cell includes a housing and an electrode assembly. The electrode assembly is housed within the housing and includes stacked electrode sheets and separators. The electrode sheet includes a current collector and active material layers disposed on both sides of the current collector in its thickness direction. The current collector includes a substrate and reinforcing protrusions. By providing reinforcing protrusions on at least one side of the substrate in the thickness direction, the strength and stiffness of the current collector are improved, the deformation resistance of the electrode sheet is enhanced, the problem of electrode sheet wrinkling is improved, and the performance of the battery cell is improved.

[0007] In some embodiments, the current collector includes a tab and an active material segment connected along a first direction, the active material layer is disposed on the active material segment, and the reinforcing protrusion is disposed on the active material segment.

[0008] In the embodiments of this application, by setting reinforcing protrusions on the active material segment, the problem of electrode wrinkling caused by the active material layer can be effectively resisted, thereby reducing the processing difficulty of the electrode.

[0009] In some embodiments, the minimum spacing X1 between the edge of the tab away from the active material segment and the reinforcing protrusion along the first direction, and the size X2 of the current collector in the first direction, satisfy 0.2*X2≤X1≤0.6*X2.

[0010] In the scheme of the embodiment of the application, when the minimum distance X1 of the tab side edge away from the active material section and the reinforcing protrusion along the first direction and the size X2 of the current collector in the first direction satisfy the above condition, the current collector reserves sufficient space for the tab, so that the reinforcing protrusion and the tab are arranged at intervals, and the processing difficulty of the pole piece is reduced.

[0011] In some embodiments, the reinforcing protrusion extends in the second direction, and the first direction and the second direction intersect.

[0012] In the scheme of the embodiment of the application, the reinforcing protrusion extending in the second direction is arranged to enhance the anti-deformation ability of the pole piece in the second direction, to improve the problem of pole piece creasing and to improve the performance of the battery monomer.

[0013] In some embodiments, the reinforcing protrusion extends in the second direction.

[0014] In the scheme of the embodiment of the application, at least two reinforcing protrusions are arranged at intervals along the first direction to enhance the anti-deformation ability of the pole piece and to improve the problem of pole piece creasing.

[0015] In some embodiments, n reinforcing protrusions are arranged on one side of the current collector, the distance X3 of adjacent reinforcing protrusions in the first direction, the size X2 of the current collector in the first direction, and n≥2 satisfy (0.4*X2) / (n-1)≤X3≤(0.8*X2) / (n-1).

[0016] In the scheme of the embodiment of the application, when the distance X3 of adjacent reinforcing protrusions in the first direction satisfies the above condition, the n reinforcing protrusions are arranged at intervals, so that the structural strength of the pole piece in the first direction is uniform, the problem of pole piece creasing is improved, and the performance of the battery monomer is improved.

[0017] In some embodiments, the substrate includes a first surface and a second surface arranged opposite in the thickness direction thereof, and the first surface and the second surface are both provided with reinforcing protrusions, and the reinforcing protrusions arranged on the first surface and the reinforcing protrusions arranged on the second surface are arranged opposite each other.

[0018] In the scheme of the embodiment of the application, the first surface and the second surface of the substrate are both provided with reinforcing protrusions, and the reinforcing protrusions arranged on the first surface and the reinforcing protrusions arranged on the second surface are arranged opposite each other, which reduces the processing difficulty of the pole piece while enhancing the anti-deformation ability of the pole piece.

[0019] In some embodiments, the substrate includes a first surface and a second surface arranged opposite in the thickness direction thereof, and the first surface and the second surface are both provided with reinforcing protrusions, and the reinforcing protrusions arranged on the first surface and the reinforcing protrusions arranged on the second surface are arranged opposite each other.

[0020] In the scheme of the embodiment of the application, the first surface and the second surface of the base are both provided with reinforcing protrusions, the reinforcing protrusions provided on the first surface and the reinforcing protrusions provided on the second surface are staggered in the first direction, so as to increase the density of the reinforcing protrusions in the reinforcing protrusion spacing direction, and enhance the anti-deformation capability of the pole piece.

[0021] In some embodiments, the reinforcing protrusion and the base are connected through a first circular arc surface.

[0022] In the scheme of the embodiment of the application, the reinforcing protrusion and the base are connected through a first circular arc surface, so as to release the stress between the reinforcing protrusion and the base, and improve the reliability of the current collector.

[0023] In some embodiments, the end of the reinforcing protrusion away from the base is provided with a second circular arc surface, and the second circular arc surface is arranged away from the base.

[0024] In the scheme of the embodiment of the application, the end of the reinforcing protrusion away from the base is provided with a second circular arc surface, and the second circular arc surface is arranged away from the base, so as to reduce the risk of the reinforcing protrusion losing the isolation member or the adjacent pole piece.

[0025] In some embodiments, the extension size L1 of the reinforcing protrusion in the thickness direction of the base, and the thickness Y1 of the base satisfy 0.1Y1≤L1≤0.3Y1.

[0026] In the scheme of the embodiment of the application, when the extension size L1 of the reinforcing protrusion in the thickness direction of the base satisfies the above condition, the problem that the anti-deformation capability of the pole piece is insufficient due to the reinforcing protrusion being too short is improved, and the problem that the energy density of the battery cell is too low due to the reinforcing protrusion being too long is also improved.

[0027] In some embodiments, the size L2 of the reinforcing protrusion in the first direction, and the thickness Y1 of the base satisfy 0.1Y1≤L2≤0.5Y1.

[0028] In the scheme of the embodiment of the application, when the size L2 of the reinforcing protrusion in the first direction satisfies the above condition, the problem that the anti-deformation capability of the pole piece is insufficient due to the reinforcing protrusion being too thin is improved, and the problem that the energy density of the battery cell is too low due to the reinforcing protrusion being too thick is also improved.

[0029] In a second aspect, the application provides a battery device, which comprises the battery cell of the above-mentioned first aspect embodiment.

[0030] In a third aspect, the application provides a power consumption device, which comprises the battery device of the above-mentioned third aspect embodiment. BRIEF DESCRIPTION OF DRAWINGS

[0031] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0032] Figure 1 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application;

[0033] Figure 2 This is a schematic diagram of the structure of a battery provided in one embodiment of this application;

[0034] Figure 3 This is a schematic diagram of the structure of a battery module provided in one embodiment of the application;

[0035] Figure 4 This is an exploded view of a single battery cell provided in an embodiment of this application;

[0036] Figure 5 This is a schematic diagram of the electrode assembly of a battery cell provided in an embodiment of this application;

[0037] Figure 6 This is a schematic diagram of the current collector structure of a battery cell provided in an embodiment of this application;

[0038] Figure 7 yes Figure 6 Front view of the central flow meter;

[0039] Figure 8 This is a schematic diagram of the current collector structure of a battery cell provided in an embodiment of this application;

[0040] Figure 9 yes Figure 8 Front view of the central flow meter;

[0041] Figure 10 This is a schematic diagram of the current collector structure of a battery cell provided in an embodiment of this application;

[0042] Figure 11 yes Figure 10 A front view of the central collector fluid.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Vehicle; 101. Motor; 102. Controller;

[0045] 2. Battery assembly; 201. Battery module; 202. Housing; 2021. First housing; 2022. Second housing;

[0046] 3. Battery cells;

[0047] 4, housing;

[0048] 5, electrode assembly; 51, tab; 52, electrode body; 53, tab piece; 54, spacer;

[0049] 6, top cover assembly;

[0050] 71, current collector; 72, active material layer; 711, base body; 712, reinforcing protrusion; 713, active material segment; 714, first surface; 715, second surface;

[0051] X, first direction; Y, second direction. DETAILED DESCRIPTION

[0052] 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.

[0053] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should be understood as the usual meaning understood by the skilled person in the field to which the embodiments of the present application belong.

[0054] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the purpose of facilitating the description of the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0055] In addition, the technical terms "first", "second" and the like are only for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0056] In the description of the embodiments of the present application, unless explicitly defined and limited otherwise, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be direct connection, can also be indirect connection through an intermediate medium, or 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.

[0057] In the description of the embodiments of the present application, unless explicitly defined and limited otherwise, the first feature is "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0058] At present, from the development of market situation, the application of power battery is more and more extensive. The power battery 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 power battery, the demand of its market is also increasing.

[0059] During the working process of the battery monomer, the electrode sheet is prone to wrinkle, which leads to the performance decline of the battery monomer.

[0060] In the related art, during the charging process of the battery monomer, lithium ions will be embedded in the anode graphite or silicon. Because of the existence of lattice expansion, a large expansion in the thickness direction of the negative electrode sheet is caused, so that the negative electrode sheet is deformed, and the problem of electrode sheet wrinkle occurs.

[0061] Based on the above problems, the embodiments of the present application provide a battery monomer. The battery monomer comprises a shell and an electrode assembly. The electrode assembly is accommodated in the shell. The electrode assembly comprises an electrode sheet and a separator which are stacked with each other. The electrode sheet comprises a current collector and active material layers arranged on both sides of the current collector in the thickness direction thereof. The current collector comprises a base body and a reinforcing protrusion. The reinforcing protrusion is arranged on at least one side of the base body in the thickness direction thereof, so as to improve the strength and rigidity of the current collector and enhance the anti-deformation capability of the electrode sheet, thereby improving the problem of electrode sheet wrinkle and improving the performance of the battery monomer.

[0062] The technical solutions described in the embodiments of the present application are applicable to a battery device and a power consumption device using the battery device.

[0063] The power consumption device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle 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 electric automobile, or a range extended automobile, and the like. The spacecraft includes an airplane, a rocket, a space shuttle, a spacecraft, and the like. The electric toy includes a fixed or mobile electric toy, for example, a game machine, an electric automobile toy, an electric ship toy, an electric airplane toy, and the like. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool, and a railway electric tool, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not specially limit the power consumption device.

[0064] In the embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0065] The battery cell 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 storage battery, and the like. The embodiments of the present application are not limited thereto. The battery cell can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, and the like. The embodiments of the present application are not limited thereto.

[0066] The battery device mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery device mentioned in the present application can include a battery module or a battery pack, and the like. The battery pack generally includes a box for packaging one or more battery cells. The box can avoid the influence of liquid or other foreign matters on the charging or discharging of the battery cell.

[0067] The battery cell includes an electrode assembly and an electrolyte, and the electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer coated on the surface of the positive electrode current collector; the positive electrode current collector includes a positive electrode current collecting part and a positive electrode tab connected to the positive electrode current collecting part, the positive electrode current collecting part is coated with the positive electrode active material layer, and the positive electrode tab is not coated with the positive electrode active material layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material layer includes a positive electrode active material, which can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer coated on the surface of the negative electrode current collector; the negative electrode current collector includes a negative electrode current collecting part and a negative electrode tab connected to the negative electrode current collecting part, the negative electrode current collecting part is coated with the negative electrode active material layer, and the negative electrode tab is not coated with the negative electrode active material layer. The material of the negative electrode current collector can be copper, and the negative electrode active material layer includes a negative electrode active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0068] It should be understood that the technical solutions described in the embodiments of the present application are not only limited to the above-described battery device and electric equipment, but can also be applied to all battery devices including a box body and electric equipment using the battery device, but for the sake of brevity, the following embodiments are described taking an electric vehicle as an example.

[0069] Please refer to Figure 1 , Figure 1 A structural schematic diagram of a vehicle 1 is provided for some embodiments of the present application. 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 vehicle, a hybrid vehicle or a range extended vehicle, etc. The vehicle 1 is internally provided with a battery device 2, which can be arranged at the bottom, head or 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 102 and a motor 101, and the controller 102 is used to control the battery to supply power to the motor 101, for example, to meet the power demand of the vehicle 1 during starting, navigation and driving.

[0070] 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, instead of or partially instead of fuel or natural gas to provide driving power for the vehicle 1.

[0071] Figure 2 A structural schematic diagram of a battery device according to an embodiment of the present application is shown.

[0072] The battery device 2 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 can include a plurality of battery cells 3 connected in series, in parallel, or in a mixed connection through a busbar component.

[0073] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells 3.

[0074] As an example, the battery cell assembly can be a battery module 201 formed by arranging and fixing a plurality of battery cells 3 into one independent module. As an example, the battery module 201 can be formed by bundling a plurality of battery cells 3 with a cable tie.

[0075] In some embodiments, the battery device can be a battery pack including a box 202 and one or more battery cell assemblies accommodated in the box 202.

[0076] As an example, the battery cell assembly can be a battery module 201, which can be accommodated in the box by fixing the battery module 201 in the box.

[0077] As an example, the battery cell assembly can also be accommodated in the box 202 by directly fixing a plurality of battery cells 3 to the box 202.

[0078] As an example, the box 202 can include a first box 2021 and a second box 2022. The first box 2021 and the second box 2022 are coupled so that an enclosed space is formed inside the box 202 to accommodate the battery cell assembly. Here, the enclosed means covered or closed, which can be sealed or unsealed. The first box 2021 can be a top cover or a bottom plate.

[0079] As an example, the box 202 can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame so that an enclosed space is formed inside the box 202 to accommodate the battery cell assembly.

[0080] In some embodiments, the box 202 can be part of the chassis structure of a vehicle. For example, part of the box 202 can be at least part of the floor of the vehicle, or part of the box 202 can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0081] Figure 3 A structural diagram of the battery module 201 according to an embodiment of the present application is shown.

[0082] In some embodiments, as Figure 2 and Figure 3As shown, the battery monomer 3 is multiple, and the multiple battery monomers 3 are connected in series or in parallel or in mixed connection to form a battery module 201. Multiple battery modules 201 are connected in series or in parallel or in mixed connection to form a whole and are contained in the box 202.

[0083] The multiple battery monomers 3 in the battery module 201 can be electrically connected through the busbar component to realize the parallel or series or mixed connection of the multiple battery monomers 3 in the battery module 201.

[0084] Figure 4 It is an embodiment provided by the present application that the battery monomer is an exploded view. The battery monomer 3 refers to the smallest unit of the battery. As shown, Figure 4 The battery monomer 3 includes a top cover assembly 6, a shell 4 and an electrode assembly 5.

[0085] The electrode assembly 5 is a component in which an electrochemical reaction occurs in the battery monomer 3. The shell 4 can contain one or more electrode assemblies 5. The electrode assembly 5 is mainly formed by winding or stacking the electrode sheet. The electrode sheet is divided into positive electrode sheet and negative electrode sheet, and an insulating member is usually arranged between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have a part of active material constituting an electrode body 52, and each of the positive electrode sheet and the negative electrode sheet has a part not having active material constituting a tab 51. The positive electrode tab and the negative electrode tab can be located at one end of the electrode body 52 or at both ends of the electrode body 52. In the charging and discharging process of the battery monomer 3, the positive active material and the negative active material react with the electrolyte, and the tab 51 connects the electrode terminal to form a current loop.

[0086] The electrode assembly 5 can be a winding structure, a laminated structure, or a hybrid structure of winding and laminating.

[0087] In some embodiments, the electrode assembly 5 is a winding structure. The positive electrode sheet and the negative electrode sheet are wound into a winding structure.

[0088] In some embodiments, the electrode assembly 5 is a laminated structure. As an example, multiple positive electrode sheets and multiple negative electrode sheets are alternately and laminatedly arranged, and multiple insulating members are arranged between any adjacent positive electrode sheets or negative electrode sheets, or the insulating members are continuously arranged and arranged between any adjacent positive electrode sheets or negative electrode sheets by folding.

[0089] In some embodiments, the shape of the electrode assembly 5 can be cylindrical, flat or polygonal, etc.

[0090] In some embodiments, the electrode assembly 5 is provided with a tab, and the tab can guide the current out of the electrode assembly. The tab includes a positive tab and a negative tab.

[0091] The battery cell 3 can include a shell. The shell 4 is a component for cooperating with the top cover assembly 6 to form an internal environment of the battery cell 3, wherein the formed internal environment can be used to accommodate the electrode assembly 5, electrolyte (not shown in the figure), and other components. The shell 4 can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film, etc. In some embodiments, the shell 4 can be a sealed structure, or can be a non-sealed structure. As an example, when the shell 4 is a non-sealed structure, the shell 4 plays a role of protecting the electrode assembly 5, and a sealing bag is further included between the shell 4 and the electrode assembly 5, which is used to package the electrode assembly and the electrolyte. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film. When the shell 4 is a sealed structure, it is used to package the electrode assembly 5, the electrolyte, and other components.

[0092] As an example, the battery cell 3 can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or a battery cell of other shapes, and the prismatic battery cell includes a square battery cell, a blade-shaped battery cell, a multi-prismatic battery cell (for example, a hexagonal battery cell, etc.), without specific limitation in the present application.

[0093] The shell 4 and the top cover assembly 6 can be independent components, one or more openings can be provided on the shell 4, and the one or more top cover assemblies 6 are used to cover the openings to form the internal environment of the battery cell 3. Alternatively, the top cover assembly 6 and the shell 4 can be integrated. Alternatively, the top cover assembly 6 and the shell 4 can form a common connecting surface before other components enter the shell, and the top cover assembly 6 is used to cover the shell 4 when it is necessary to seal the internal environment of the shell 4.

[0094] In some embodiments, the electrode terminal can be provided on the top cover assembly 6, or can be provided on the shell 4, and the electrode terminal is electrically connected with the tab 51. The electrode terminal can be directly connected with the tab 51, or can be indirectly connected with the tab 51 through an adapter mechanism.

[0095] Please refer to Figure 5 and Figure 6 , Figure 5 is a structural schematic diagram of an electrode assembly of a battery cell provided by an embodiment of the present application; Figure 6 is a structural schematic diagram of a current collector of a battery cell provided by an embodiment of the present application.

[0096] In a first aspect, as Figure 4 to Figure 6As shown, the battery cell 3 provided by the present application comprises a shell 4 and an electrode assembly 5; the electrode assembly 5 is accommodated in the shell 4, and the electrode assembly 5 comprises mutually superposed pole pieces 53 and separators 54, the pole piece 53 comprises a current collector 71 and active material layers 72 arranged on both sides of the current collector 71 in the thickness direction thereof, wherein the current collector 71 comprises a base body 711 and reinforcing protrusions 712 arranged on at least one side of the base body 711 in the thickness direction thereof.

[0097] In the scheme of the embodiment of the present application, the battery cell 3 comprises a shell 4 and an electrode assembly 5, the electrode assembly 5 is accommodated in the shell 4, and the electrode assembly 5 comprises mutually superposed pole pieces 53 and separators 54, the pole piece 53 comprises a current collector 71 and active material layers 72 arranged on both sides of the current collector 71 in the thickness direction thereof, and the current collector 71 comprises a base body 711 and reinforcing protrusions 712, the strength and rigidity of the current collector 71 are improved by arranging the reinforcing protrusions 712 on at least one side of the base body 711 in the thickness direction thereof, the deformation resistance of the pole piece 53 is enhanced, the problem of the pole piece 53 being wrinkled is improved, and the performance of the battery cell 3 is improved.

[0098] The pole piece 53 comprises positive pole pieces 53 and negative pole pieces 53, and the negative pole pieces 53 are more prone to being wrinkled than the positive pole pieces 53 in the related art, so the reinforcing protrusions 712 can be arranged on the negative pole pieces 53 to enhance the deformation resistance of the negative pole pieces 53.

[0099] Optionally, the electrode assembly 5 is wound by the pole pieces 53, or the electrode assembly 5 is stacked by a plurality of pole pieces 53.

[0100] The electrode assembly 5 comprises the pole pieces 53 and the separators 54, and the separators 54 are arranged between adjacent pole pieces 53 to insulate the adjacent pole pieces 53.

[0101] The pole piece 53 comprises the current collector 71 and the active material layers 72, and the active material layers 72 cover the base body 711 and the reinforcing protrusions 712, specifically, the positive pole piece 53 comprises a positive current collector 71 and a positive active material layer 72; and the negative pole piece 53 comprises a negative current collector 71 and a negative active material layer 72.

[0102] Illustratively, the current collector 71 can be a copper foil or an aluminum foil, etc.

[0103] The current collector 71 comprises the base body 711 and the reinforcing protrusions 712, the reinforcing protrusions 712 are arranged on one side of the base body 711 in the thickness direction thereof to reduce the processing difficulty and reduce the size of the current collector 71 in the thickness direction thereof, or the reinforcing protrusions 712 are arranged on both sides of the base body 711 in the thickness direction thereof to arrange more reinforcing protrusions 712 and enhance the deformation resistance of the pole piece 53.

[0104] Optionally, the base body 711 and the reinforcing protrusion 712 are integrally formed to improve the structural strength of the current collector 71. For example, the base body 711 and the reinforcing protrusion 712 are rolled from the same base material.

[0105] Optionally, one or more reinforcing protrusions 712 are arranged on at least one side of the base body 711 in the thickness direction. For example, one, two or five reinforcing protrusions 712 are arranged on the base body 711.

[0106] Optionally, the size and shape of the reinforcing protrusion 712 can be designed as desired. For example, the reinforcing protrusion 712 is in the shape of a hemisphere or a cube.

[0107] In some embodiments, as shown in Figure 5 and Figure 6 , the current collector 71 includes the tab 51 and an active material section 713 connected along the first direction X, the active material layer 72 is arranged on the active material section 713, and the reinforcing protrusion 712 is arranged on the active material section 713.

[0108] In these embodiments, by arranging the reinforcing protrusion 712 on the active material section 713, the problem of the tab 53 being wrinkled due to the active material layer 72 is effectively resisted, and the processing difficulty of the tab 53 is reduced.

[0109] In the prior art, the tab 53 may be wrinkled due to the expansion of the active material layer 72. Therefore, in the embodiments of the present application, the reinforcing protrusion 712 is arranged on the active material section 713 to resist the expansion and deformation of the active material layer 72, thereby improving the problem of the tab 53 being wrinkled.

[0110] Because the bonding force between the active material layer 72 and the current collector 71 is strong, in the case where the reinforcing protrusion 712 is arranged on the current collector 71, the strength and rigidity of the reinforcing protrusion 712 are enhanced, so that even if the active material layer 72 has a tendency to deform, the tab 53 is not prone to being wrinkled.

[0111] Optionally, the specific size of the tab 51 and the active material section 713 can be designed as desired.

[0112] Please refer to Figure 7 , Figure 7 , which is a front view of the current collector in Figure 6 .

[0113] In some embodiments, as shown in Figure 5 to Figure 7 , the minimum distance X1 between the side edge of the tab 51 away from the active material section 713 and the reinforcing protrusion 712 along the first direction X, and the size X2 of the current collector 71 in the first direction X satisfy 0.2*X2≤X1≤0.6*X2.

[0114] In these embodiments, when the minimum distance X1 between the side edge of the tab 51 away from the active material section 713 and the reinforcing protrusion 712 along the first direction X, and the size X2 of the current collector 71 along the first direction X satisfy the above condition, the current collector 71 reserves sufficient space for the tab 51, so that the reinforcing protrusion 712 is arranged apart from the tab 51, and the processing difficulty of the tab 53 is reduced.

[0115] In these embodiments, when the minimum distance X1 between the side edge of the tab 51 away from the active material section 713 and the reinforcing protrusion 712 along the first direction X, and the size X2 of the current collector 71 along the first direction X satisfy the above condition, the current collector 71 reserves sufficient space for the tab 51, so that the reinforcing protrusion 712 is arranged apart from the tab 51, and the processing difficulty of the tab 53 is reduced.

[0116] In these embodiments, the minimum distance X1 between the side edge of the tab 51 away from the active material section 713 and the reinforcing protrusion 712 along the first direction X is 0.2*X2, 0.4*X2, 0.6*X2, etc.

[0117] In these embodiments, the size X2 of the current collector 71 along the first direction X satisfies 80mm≤X2≤120mm, and the minimum distance X1 between the side edge of the tab 51 away from the active material section 713 and the reinforcing protrusion 712 along the first direction X satisfies 16mm≤X1≤72mm. In these embodiments, the size of the current collector 71 along the first direction X is 80mm, 100mm, 120mm, etc.

[0118] In some embodiments, as shown in FIG. 6, the reinforcing protrusion 712 extends along the second direction Y, and the first direction X and the second direction Y intersect. Figure 5 to Figure 7

[0119] In these embodiments, by arranging the reinforcing protrusion 712 extending along the second direction Y, the anti-deformation ability of the tab 53 along the second direction Y is enhanced, the problem of the tab 53 being wrinkled is improved, and the performance of the battery monomer 3 is improved.

[0120] When the tab 53 is wrinkled, the tab 53 will shrink and deform along multiple directions. When the extending direction of the reinforcing protrusion 712 is parallel to the deforming direction of the tab 53, the anti-wrinkling and anti-deformation ability of the reinforcing protrusion 712 is stronger.

[0121] In the related art, when the tab 53 is wrinkled, the deformation of the tab 53 along the second direction Y is more obvious than the deformation along the first direction X. Therefore, in the embodiments of the present application, the reinforcing protrusion 712 extends along the second direction Y to enhance the anti-deformation ability of the tab 53.

[0122] Optionally, the reinforcing protrusion 712 extends to both ends of the tab 53 along the second direction Y, and the size of the reinforcing protrusion 712 is lengthened to enhance the anti-deformation ability of the tab 53.

[0123] In some embodiments, as shown in FIG. 6, the reinforcing protrusion 712 extends along the second direction Y, and the first direction X and the second direction Y intersect. Figure 5 to Figure 7 ​As shown, at least two reinforcing protrusions 712 are arranged at intervals along the first direction X.

[0124] In these embodiments, at least two reinforcing protrusions 712 are arranged at intervals along the first direction X to enhance the deformation resistance of the pole piece 53 and improve the creasing problem of the pole piece 53.

[0125] Optionally, 2 or 3 or 4 or 7 or 10 or the like reinforcing protrusions 712 are arranged at intervals along the first direction X.

[0126] In some embodiments, as shown, n reinforcing protrusions 712 are arranged on one side of the current collector 71, and the interval X3 of adjacent reinforcing protrusions 712 in the first direction X, and the size X2 of the current collector 71 in the first direction X satisfy (0.4*X2) / (n-1)≤X3≤(0.8*X2) / (n-1), and n≥2. Figure 5 to Figure 7 In these embodiments, when the interval X3 of adjacent reinforcing protrusions 712 in the first direction X satisfies the above condition, the n reinforcing protrusions 712 are arranged at intervals, so that the structural strength of the pole piece 53 in the first direction X is uniform, thereby improving the creasing problem of the pole piece 53 and improving the performance of the battery monomer 3.

[0127] On one side of the current collector 71, n reinforcing protrusions 712 are arranged, and X3≤(X2-X1) / (n-1). Optionally, X3=(X2-X1) / (n-1) to increase the distribution range of the reinforcing protrusions 712 and improve the uniformity of the strength and rigidity of the current collector 71.

[0128] Optionally, on one side of the current collector 71, n reinforcing protrusions 712 are arranged, and n can be 2 or 3 or 4 or 7 or 10 or the like.

[0129] In some embodiments, as shown, the reinforcing protrusion 712 and the base body 711 are connected through a first circular arc surface.

[0130] Figure 5 to Figure 7 In these embodiments, the reinforcing protrusion 712 and the base body 711 are connected through a first circular arc surface to release the stress between the reinforcing protrusion 712 and the base body 711 and improve the reliability of the current collector 71.

[0131] The reinforcing protrusion 712 and the base body 711 are connected through a first circular arc surface, or in other words, an R angle is arranged between the outer surface of the reinforcing protrusion 712 and the outer surface of the base body 711, and the stress between the two is released through the R angle, and the risk of burrs at the connection between the reinforcing protrusion 712 and the base body 711 piercing the pole piece 53 or the separator 54 is reduced.

[0132] The reinforcing protrusion 712 and the base body 711 are connected through a first circular arc surface, or in other words, an R angle is arranged between the outer surface of the reinforcing protrusion 712 and the outer surface of the base body 711, and the stress between the two is released through the R angle, and the risk of burrs at the connection between the reinforcing protrusion 712 and the base body 711 piercing the pole piece 53 or the separator 54 is reduced.

[0133] ​Optionally, the radius R1 of the first arc surface and the dimension L2 of the reinforcing protrusion 712 in the first direction X satisfy 0.1*L2≤R1≤0.3*L2. This reduces the difficulty of setting the first arc surface and also allows for sufficient stress release between the base 711 and the reinforcing protrusion 712 through the first arc surface. For example, R1 can be 0.1*L2, 0.2*L2, 0.3*L2, etc.

[0134] In some embodiments, such as Figure 5 to Figure 7 As shown, the reinforcing protrusion 712 has a second arc surface at one end facing away from the substrate 711, and the second arc surface is protruding away from the substrate 711.

[0135] In these embodiments, the reinforcing protrusion 712 is provided with a second arc surface at one end away from the substrate 711. The second arc surface is provided with a protrusion away from the substrate 711, which reduces the risk of the reinforcing protrusion 712 damaging the separator 54 or the adjacent electrode 53.

[0136] The reinforcing protrusion 712 has a second arc surface at one end away from the substrate 711, that is, the reinforcing protrusion 712 has an R-angle at one end away from the substrate 711. The R-angle reduces the risk of the reinforcing protrusion 712 puncturing the separator 54 or the electrode 53.

[0137] Optionally, the radius R2 of the second arc surface satisfies R1≤R2≤2*R1. For example, R2 can be R1, 1.5*R1, 2*R1, etc.

[0138] In some embodiments, such as Figure 5 to Figure 7 As shown, the extension dimension L1 of the reinforcing protrusion 712 in the thickness direction of the substrate 711 and the thickness Y1 of the substrate 711 satisfy 0.1Y1≤L1≤0.3Y1.

[0139] In these embodiments, when the extension dimension L1 of the reinforcing protrusion 712 in the thickness direction of the substrate 711 satisfies the above conditions, it improves the problem that the electrode 53 has insufficient resistance to deformation due to the reinforcing protrusion 712 being too short, and also improves the problem that the energy density of the battery cell 3 is too low due to the reinforcing protrusion 712 being too long.

[0140] The extension dimension of the reinforcing protrusion 712 in the thickness direction of the substrate 711 is also the length of the reinforcing protrusion 712.

[0141] Optionally, the reinforcing protrusions 712 disposed on the same side of the thickness direction of the substrate 711 have the same length, so that the current collector 71 has uniform dimensions in the thickness direction.

[0142] For example, the extension dimension L1 of the reinforcing protrusion 712 in the thickness direction of the substrate 711 can be 0.1Y1, 0.2Y1, 0.3Y1, etc.

[0143] Exemplarily, the thickness Y1 of the base body 711 satisfies 4 μm≤Y1≤6 μm, and the thickness of the base body 711 is exemplarily 4 μm, 5 μm, 6 μm, etc.

[0144] In some embodiments, as shown in Figure 5 to Figure 7 Exemplarily, the size L2 of the reinforcing protrusion 712 in the first direction X satisfies 0.1Y1≤L2≤0.5Y1.

[0145] In these embodiments, when the size L2 of the reinforcing protrusion 712 in the first direction X satisfies the above condition, the problem that the reinforcing protrusion 712 is too thin to improve the anti-deformation ability of the pole piece 53 is solved, and the problem that the reinforcing protrusion 712 is too thick to reduce the energy density of the battery cell 3 is also solved.

[0146] The size of the reinforcing protrusion 712 in the first direction X is the thickness of the reinforcing protrusion 712.

[0147] Optionally, the thicknesses of the reinforcing protrusions 712 arranged on the same side of the thickness direction of the base body 711 are the same, so that the thickness direction size of the current collector 71 is uniform.

[0148] Exemplarily, the extension size L2 of the reinforcing protrusion 712 in the thickness direction of the base body 711 can be 0.1Y1, 0.25Y1, 0.5Y1, etc.

[0149] Please refer to Figure 8 and Figure 9 , Figure 8 is a structural schematic diagram of a current collector of a battery cell provided in an embodiment of the present application; Figure 9 is Figure 8 a front view of the current collector in

[0150] In some embodiments, as shown in Figure 8 and Figure 9 Exemplarily, the base body 711 includes a first surface 714 and a second surface 715 arranged oppositely in the thickness direction thereof, and the first surface 714 and the second surface 715 are both provided with the reinforcing protrusion 712, and the reinforcing protrusion 712 arranged on the first surface 714 and the reinforcing protrusion 712 arranged on the second surface 715 are arranged oppositely.

[0151] In these embodiments, the first surface 714 and the second surface 715 of the base body 711 are both provided with the reinforcing protrusion 712, and the reinforcing protrusion 712 arranged on the first surface 714 and the reinforcing protrusion 712 arranged on the second surface 715 are arranged oppositely, so that the anti-deformation ability of the pole piece 53 is enhanced, and the processing difficulty of the pole piece 53 is reduced.

[0152] The reinforcing protrusions 712 arranged on the first surface 714 and the reinforcing protrusions 712 arranged on the second surface 715 are arranged opposite to each other, and the orthographic projection of the reinforcing protrusions 712 arranged on the first surface 714 on the base body 711 coincides with the orthographic projection of the reinforcing protrusions 712 arranged on the second surface 715 on the base body 711.

[0153] Optionally, the two reinforcing protrusions 712 arranged opposite on the first surface 714 and the second surface 715 are of the same shape and size, so that the anti-deformation ability of the pole piece 53 on both sides in the thickness direction is similar.

[0154] Please refer to Figure 10 and Figure 11 , Figure 10 is a structural schematic diagram of a current collector of a battery monomer provided in an embodiment of the present application; Figure 11 is Figure 10 a front view of the current collector in

[0155] In some embodiments, as shown in Figure 10 and Figure 11 , the base body 711 includes a first surface 714 and a second surface 715 arranged opposite in the thickness direction, and the first surface 714 and the second surface 715 are both provided with reinforcing protrusions 712, and the reinforcing protrusions 712 arranged on the first surface 714 and the reinforcing protrusions 712 arranged on the second surface 715 are arranged staggered in the first direction X.

[0156] In these embodiments, the first surface 714 and the second surface 715 of the base body 711 are both provided with reinforcing protrusions 712, and the reinforcing protrusions 712 arranged on the first surface 714 and the reinforcing protrusions 712 arranged on the second surface 715 are arranged staggered in the first direction X, so as to increase the density of the reinforcing protrusions 712 in the spacing direction of the reinforcing protrusions 712, and enhance the anti-deformation ability of the pole piece 53.

[0157] Optionally, along the first direction X, at least one reinforcing protrusion 712 is arranged on the second surface 715 between the two reinforcing protrusions 712 on the first surface 714, and exemplarily, the second surface 715 is provided with 1, 2, 3, or 5 reinforcing protrusions 712; or along the first direction X, at least one reinforcing protrusion 712 is arranged on the first surface 714 between the two reinforcing protrusions 712 on the second surface 715, and exemplarily, the first surface 714 is provided with 1, 2, 3, or 5 reinforcing protrusions 712.

[0158] Optionally, along the first direction X, between the two reinforcing protrusions 712 of the first surface 714, one reinforcing protrusion 712 is arranged on the second surface 715, and the reinforcing protrusion 712 of the second surface 715 is arranged centrally between the two reinforcing protrusions 712 of the first surface 714, so as to enhance the uniformity of the strength and rigidity of the pole piece 53 in the first direction X.

[0159] Optionally, the reinforcing protrusions 712 arranged on the first surface 714 and the second surface 715 are of the same shape and size or different shape and size.

[0160] In the second aspect, the application provides a battery device 2 comprising the battery cell 3 of the first aspect.

[0161] In the third aspect, the application provides a power consumption device comprising the battery device 2 of the third aspect.

[0162] In some embodiments, as Figure 1 to Figure 11As shown, the battery cell 3 comprises a shell 4 and an electrode assembly 5; the electrode assembly 5 is accommodated in the shell 4, the electrode assembly 5 comprises mutually superposed pole pieces 53 and separators 54, the pole piece 53 comprises a current collector 71 and active material layers 72, the active material layers 72 are arranged on both sides of the current collector 71 in the thickness direction thereof, wherein the current collector 71 comprises a base body 711 and reinforcing protrusions 712 arranged on at least one side of the base body 711 in the thickness direction thereof, the current collector 71 comprises a tab 51 and an active material segment 713 connected along a first direction X, the active material layers 72 are arranged on the active material segment 713, the reinforcing protrusions 712 are arranged on the active material segment 713, the minimum distance X1 between the side edge of the tab 51 away from the active material segment 713 and the reinforcing protrusions 712 along the first direction X, the size X2 of the current collector 71 in the first direction X, satisfying 0.2*X2≤X1≤0.6*X2, the reinforcing protrusions 712 extend in a second direction Y, the reinforcing protrusions 712 extend in the second direction Y, n reinforcing protrusions 712 are arranged on one side of the current collector 71, the distance X3 between adjacent reinforcing protrusions 712 in the first direction X, the size X2 of the current collector 71 in the first direction X, satisfying (0.7*X2) / (n-1)≤X3≤(0.9*X2) / (n-1), n≥2, the base body 711 comprises a first surface 714 and a second surface 715 arranged oppositely in the thickness direction thereof, the first surface 714 and the second surface 715 are both provided with the reinforcing protrusions 712, the reinforcing protrusions 712 arranged on the first surface 714 and the reinforcing protrusions 712 arranged on the second surface 715 are arranged opposite to each other, or the base body 711 comprises a first surface 714 and a second surface 715 arranged oppositely in the thickness direction thereof, the first surface 714 and the second surface 715 are both provided with the reinforcing protrusions 712, the reinforcing protrusions 712 arranged on the first surface 714 and the reinforcing protrusions 712 arranged on the second surface 715 are arranged staggered in the first direction X, the reinforcing protrusions 712 and the base body 711 are connected through a first arc surface transition, one end of the reinforcing protrusion 712 away from the base body 711 is provided with a second arc surface, the second arc surface is arranged protruding away from the base body 711, the extension size L1 of the reinforcing protrusion 712 in the thickness direction of the base body 711, the thickness Y1 of the base body 711, satisfying 0.1Y1≤L1≤0.3Y1, the size L2 of the reinforcing protrusion 712 in the first direction X, the thickness Y1 of the base body 711, satisfying 0.1Y1≤L2≤0.5Y1.

[0163] In the embodiments, the battery cell 3 comprises a casing 4 and an electrode assembly 5 accommodated in the casing 4, the electrode assembly 5 comprising mutually superposed pole pieces 53 and separators 54, the pole piece 53 comprising a current collector 71 and active material layers 72 provided on both sides of the current collector 71 in the thickness direction of the current collector 71, the current collector 71 comprising a base body 711 and a reinforcing protrusion 712, the reinforcing protrusion 712 being provided on at least one side of the base body 711 in the thickness direction of the base body 711 to improve the strength and rigidity of the current collector 71, to enhance the deformation resistance of the pole piece 53, to improve the problem of creases of the pole piece 53, and to improve the performance of the battery cell 3.

[0164] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. 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 in that, include: case; An electrode assembly is housed within the housing. The electrode assembly includes stacked electrode sheets and spacers. Each electrode sheet includes a current collector and an active material layer, the active material layer being disposed on both sides of the current collector in its thickness direction. The current collector includes a substrate and a reinforcing protrusion, wherein the reinforcing protrusion is disposed on at least one side of the substrate in its thickness direction.

2. The battery cell according to claim 1, characterized in that, The current collector includes a tab and an active material segment connected along a first direction, the active material layer is disposed on the active material segment, and the reinforcing protrusion is disposed on the active material segment.

3. The battery cell according to claim 2, characterized in that, The minimum distance X1 between the edge of the tab away from the active material segment and the reinforcing protrusion along the first direction, and the dimension X2 of the current collector in the first direction, satisfy 0.2*X2≤X1≤0.6*X2.

4. The battery cell according to claim 2, characterized in that, The reinforcing protrusion extends in a second direction, where the first and second directions intersect.

5. The battery cell according to claim 4, characterized in that, At least two of the reinforcing protrusions are spaced apart along the first direction.

6. The battery cell according to claim 5, characterized in that, n reinforcing protrusions are provided on one side of the current collector, the spacing between adjacent reinforcing protrusions in the first direction is X3, and the size of the current collector in the first direction is X2, satisfying (0.4*X2) / (n-1)≤X3≤(0.8*X2) / (n-1), n≥2.

7. The battery cell according to any one of claims 2-6, characterized in that, The substrate includes a first surface and a second surface disposed opposite to each other in its thickness direction, and both the first surface and the second surface are provided with the reinforcing protrusions. The reinforcing protrusions on the first surface and the reinforcing protrusions on the second surface are arranged facing each other.

8. The battery cell according to any one of claims 2-6, characterized in that, The substrate includes a first surface and a second surface disposed opposite to each other in its thickness direction, and both the first surface and the second surface are provided with the reinforcing protrusions. The reinforcing protrusions disposed on the first surface and the reinforcing protrusions disposed on the second surface are staggered in the first direction.

9. The battery cell according to any one of claims 1-8, characterized in that, The reinforcing protrusion and the substrate are connected by a first arc surface.

10. The battery cell according to any one of claims 1-9, characterized in that, The reinforcing protrusion has a second arc surface at one end facing away from the substrate, and the second arc surface is provided facing away from the substrate protrusion.

11. The battery cell according to any one of claims 1-10, characterized in that, The reinforcing protrusion extends by dimension L1 in the thickness direction of the substrate, and the thickness Y1 of the substrate satisfies 0.1Y1≤L1≤0.3Y1.

12. The battery cell according to any one of claims 1-11, characterized in that, The dimension L2 of the reinforcing protrusion in the first direction and the thickness Y1 of the substrate satisfy 0.1Y1≤L2≤0.5Y1.

13. A battery device, characterized in that, Includes the battery cell described in any one of claims 1-12 above.

14. An electrical appliance, characterized in that, Includes the battery device described in claim 13 above.

Images