Battery cell, 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, an electrode assembly and at least one insulating part, the electrode assembly is accommodated in the shell, and a pole piece of the electrode assembly comprises a functional part coated with an active material layer and an empty foil part not coated with the active material layer; the function part comprises a base body area and a first thinned area, the thickness of the first thinned area is smaller than that of the base body area, and the first thinned area is located at the end, in the first direction, of the function part. The at least one insulating part is attached to the first thinning area and exceeds one end, back to the base body area, of the first thinning area in the first direction. According to the battery monomer provided by the invention, the stress of the insulating part on the functional part is reduced, so that the problem of lithium precipitation of the pole piece is reduced, and the reliability of the battery monomer is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery device, and an electrical device. Background Art

[0002] Battery devices are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric planes, electric ships, electric toy cars, electric toy ships, electric toy planes, and power tools, etc.

[0003] In the development of battery device technology, in addition to improving the performance of battery devices, the reliability of battery devices is also an issue that needs to be considered. Therefore, how to improve the reliability of battery devices is an issue that needs to be continuously improved in battery device technology. Utility Model Content

[0004] The present application provides a battery device and an electrical device to improve the reliability of the battery device.

[0005] This application is achieved through the following technical solutions:

[0006] In a first aspect, a battery cell provided by an embodiment of the present application includes a housing, an electrode assembly, and at least one insulating member. The electrode assembly is housed within the housing. The electrode sheet of the electrode assembly includes a functional portion coated with an active material layer and a hollow foil portion not coated with the active material layer. The functional portion includes a base region and a first skived region. The thickness of the first skived region is less than that of the base region, and the first skived region is located at an end of the functional portion along a first direction. At least one insulating member is attached to the first skived region and extends beyond an end of the first skived region facing away from the base region along the first direction.

[0007] The battery cell provided in the embodiment of the present application, by attaching the insulating part to the first thinned area, is beneficial to reducing the stress of the insulating part on the functional part while reducing the risk of burrs at the end of the functional part damaging the diaphragm through the insulating part, thereby helping to reduce the problem of lithium plating on the electrode, thereby helping to improve the reliability of the battery cell.

[0008] In some embodiments, the insulating member has a first end surface located at one end of the insulating member along the first direction, and along the thickness direction of the functional portion, at least a portion of an orthographic projection of the first end surface is located within the first thinned region.

[0009] In the above scheme, the orthographic projection of the first end face is at least partially located in the first thinning area, and the step formed by the first end face of the insulating part in the first thinning area is smaller, which has smaller stress on the first thinning area, which is beneficial to further reduce the stress of the end of the insulating part on the functional part, and further help reduce the risk of lithium plating in the electrode.

[0010] In some embodiments, at least one insulating member includes at least two insulating members, and the at least two insulating members include a first insulating member and a second insulating member. The first insulating member and the second insulating member are respectively arranged on both sides of the first thinning area along the thickness direction of the functional part, and the parts of the first insulating member and the second insulating member that exceed the functional part are fitted together.

[0011] In the above solution, the first insulating member and the second insulating member cover the ends of the first thinned area on both sides in the thickness direction to reduce the risk of burrs at the ends of the functional part piercing the diaphragm or the electrode sheet, thereby reducing the risk of internal short circuit in the electrode assembly.

[0012] In some embodiments, the insulating member has a first end surface, the first end surface being located at one end of the insulating member along the first direction, and an orthographic projection of the first end surface along the thickness direction of the functional portion being located within the functional portion. The first end surface of the first insulating member and the first end surface of the second insulating member are staggered along the thickness direction.

[0013] In the above solution, it is beneficial to reduce the size of the step generated by the first end face of the first insulating member and the first end face of the second insulating member in the functional part, further reduce the stress of the insulating member on the pole piece, and thus help reduce the risk of lithium plating in the pole piece.

[0014] In some embodiments, the insulating member includes a first sub-segment, a second sub-segment, and a connecting segment. The first sub-segment and the second sub-segment are respectively disposed on opposite sides of the functional portion along its thickness direction, and the connecting segment connects the first and second sub-segments. The first sub-segment has a first end face, which is located at an end of the first sub-segment facing away from the connecting segment. The second sub-segment has a second end face, which is located at an end of the second sub-segment facing away from the connecting segment. The first and second end faces are offset along the thickness direction.

[0015] In the above solution, the insulating member includes a first sub-segment, a second sub-segment, and a connecting segment, and the first end face and the second end face are staggered in the thickness direction. This is beneficial to reducing the risk of burrs at the end of the first thinned area puncturing the diaphragm. In addition, the insulating member can be folded and attached to both sides of the first thinned area, which is also beneficial to simplifying the structure of the electrode assembly and reducing the stress of the insulating member on the functional part of the electrode, further reducing the risk of lithium deposition on the electrode.

[0016] In some embodiments, at least a portion of an orthographic projection of the first end surface along the thickness direction is located inside the first thinned region; and / or at least a portion of an orthographic projection of the second end surface along the thickness direction is located inside the first thinned region.

[0017] In the above solution, it is beneficial to reduce the step size of the first end face and / or the second end face in the functional part, further beneficial to reduce the stress of the insulating part on the functional part, and thus reduce the risk of lithium plating of the electrode.

[0018] In some embodiments, the electrode assembly includes a positive electrode sheet, and the electrode sheet is a positive electrode sheet.

[0019] In the above scheme, the positive electrode sheet is provided with a first thinned area, which is beneficial to reducing the risk that lithium ions released from the positive electrode sheet cannot be taken up by the negative electrode sheet, and is beneficial to reducing the stress of the insulating component on the positive electrode sheet, and further beneficial to reducing the risk of lithium plating in the electrode assembly.

[0020] In some embodiments, a surface of the first thinned region facing the insulating member is straight, arc-shaped, or stepped.

[0021] In the above solution, the manufacturing of the thinned area is facilitated while reducing the stress of the insulating member on the pole piece in the first thinned area.

[0022] In some embodiments, the thickness of the first thinned region tends to decrease from an end of the first thinned region facing the base region to an end facing away from the base region.

[0023] In the above solution, the manufacturing of the thinned area is facilitated while reducing the stress of the insulating member on the pole piece in the first thinned area.

[0024] In some embodiments, the first thinned regions are provided at both ends of the base region along the first direction, and at least two insulating members are respectively provided at the first thinned regions at both ends of the functional portion along the first direction.

[0025] In the above scheme, the risk of burrs at both ends of the functional part of the pole piece along the first direction damaging the diaphragm can be reduced, and the stress of the insulating part on the first thinned area at both ends of the functional part along the first direction can be reduced, which is conducive to further reducing the risk of lithium plating of the pole piece.

[0026] In some embodiments, the hollow foil portion is provided at an end portion of the functional portion along the second direction, and the first direction intersects the second direction.

[0027] In the above solution, the empty foil portion can be the tab of the electrode assembly, which is led out in the second direction, and the first direction intersects with the second direction. This is beneficial to reducing the stress at the end of the electrode sheet along the direction intersecting with the tab leading direction.

[0028] In some embodiments, the pole piece is wound along the first direction, and the first thinned region is provided at the end of the innermost circle of the base region, and / or the first thinned region is provided at the end of the outermost circle of the base region.

[0029] In the above scheme, the first thinning area can be the starting end or the ending end of the winding of the pole piece, so as to protect the starting end and / or the ending end of the winding of the pole piece respectively, and reduce the risk of burrs at the ending end and / or the starting end of the pole piece damaging the pole piece.

[0030] In some embodiments, the pole piece includes arc segments and straight segments alternately arranged along the first direction, and the first thinned area is located in the arc segments.

[0031] In the above solution, the first thinning area is located in the arc segment. The gap between the pole pieces in the arc segment is larger, and there is more space to accommodate the insulating parts, which is beneficial to reducing the stress of the insulating parts on the functional parts and further beneficial to reducing the risk of lithium plating of the pole pieces.

[0032] In some embodiments, the functional parts are stacked along their thickness direction, and the first direction, the second direction, and the thickness direction are perpendicular to each other.

[0033] In the above scheme, the electrode assembly is arranged in a stacked form, which facilitates the preparation of the electrode assembly, and at least one end of the electrode along the first direction can be protected by an insulating member, reducing the risk of burrs on the end of the electrode along the first direction piercing the diaphragm.

[0034] In some embodiments, along the second direction, at least one end of the insulating member is disposed beyond the functional portion.

[0035] In the above solution, the risk of burrs on the ends of the functional part along the first direction and along the second direction piercing the diaphragm is further reduced, which is further helpful to reduce the risk of internal short circuit of the electrode assembly.

[0036] In some embodiments, along the second direction, the insulating member is disposed beyond the hollow foil portion.

[0037] In the above solution, the insulating member is arranged to extend beyond the hollow foil portion along the second direction, which facilitates detection of whether the insulating member is provided and is beneficial to improving product yield.

[0038] In some embodiments, the electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator, the separator is disposed between the positive electrode sheet and the negative electrode sheet, and the insulating member extends beyond at least one end of the separator along the second direction.

[0039] In the above solution, the insulating member extends beyond the diaphragm along the second direction, which facilitates detection of whether the insulating member is provided, and is beneficial to improving product yield.

[0040] In some embodiments, the functional portion further includes a second thinning area, which is located at the end of the base area along the second direction. At least one insulating member is attached to the second thinning area and extends beyond the end of the second thinning area facing away from the base area along the second direction.

[0041] In the above scheme, a first thinning zone is set at the end of the functional part along the first direction, and a second thinning zone is set at the end where the function is not along the second direction. This is beneficial to reducing the risk of burrs at the ends of the functional part along the first direction and the second direction damaging the diaphragm through the insulating part, and is beneficial to reducing the stress of the insulating part on the first thinning zone and the second thinning zone of the functional part, so as to reduce the stress of the insulating part on the functional part, thereby reducing the risk of lithium plating on the electrode.

[0042] In some embodiments, the hollow foil portion is provided at an end portion of the functional portion along the first direction.

[0043] In the above scheme, the electrode tab of the electrode assembly is led out from the first direction, and the insulating part is arranged on the side of the functional part close to the tab, which is beneficial to reducing the risk of burrs on the functional part piercing the tab and the diaphragm, and is beneficial to reducing the risk of lithium deposition at the end of the electrode along the first direction.

[0044] In some embodiments, the hollow foil portion includes spaced tabs, the first thinned area includes a tab lead-out sub-portion and a non-tab lead-out sub-portion, the tab is only led out from the tab lead-out sub-portion, and the insulating member is provided in at least a portion of the non-tab lead-out sub-portion.

[0045] In the above solution, the insulating member covers at least a portion of the non-tab lead-out sub-portion, which helps to reduce the risk of burrs on the non-tab lead-out sub-portion piercing the diaphragm and causing internal short circuits in the battery cell.

[0046] In a second aspect, the present application provides a battery device, which includes the battery device provided by any of the above embodiments.

[0047] The battery device provided in the embodiment of the present application has the same technical effects as any of the battery cells provided in any of the above embodiments, and thus will not be described in detail here.

[0048] In a third aspect, an embodiment of the present application provides an electrical device, which includes the battery device provided in the above embodiment, and the battery device is used to provide electrical energy.

[0049] The electrical device provided in the embodiment of the present application has the same technical effect as the battery device provided in the above embodiment.

[0050] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application;

[0053] Figure 2 A schematic diagram of the structure of a battery device provided in an embodiment of the present application;

[0054] Figure 3 A structural schematic diagram of a battery module in a battery device provided by an embodiment of the present application;

[0055] Figure 4 An explosion structural schematic diagram of a battery cell provided by an embodiment of the present application;

[0056] Figure 5 A partial structural schematic diagram of a battery cell provided by an embodiment of the present application;

[0057] Figure 6 A structural schematic diagram of a battery cell provided by an embodiment of the present application; Figure 5 A sectional structural schematic diagram along A-A

[0058] Figure 7 A structural schematic diagram of a battery cell provided by an embodiment of the present application; Figure 5 Another sectional structural schematic diagram along A-A

[0059] Figure 8 A structural schematic diagram of a battery cell provided by an embodiment of the present application; Figure 5 Still another sectional structural schematic diagram along A-A

[0060] Figure 9 A sectional structural schematic diagram of a partial structure in a battery cell provided by an embodiment of the present application;

[0061] Figure 10 Another sectional structural schematic diagram of a partial structure in a battery cell provided by an embodiment of the present application;

[0062] Figure 11 A top view of an electrode assembly in a battery cell provided by an embodiment of the present application;

[0063] Figure 12 A partial structural schematic diagram of a battery cell provided by an embodiment of the present application;

[0064] Figure 13 A partial structural schematic diagram of a battery cell provided by an embodiment of the present application;

[0065] Figure 14 A top view of another electrode assembly in a battery cell provided by an embodiment of the present application.

[0066] In the drawings, the drawings are not necessarily drawn according to scale.

[0067] Explanation of reference signs:

[0068] 1 - vehicle

[0069] 10 - battery device; 111 - first sub-box body; 112 - second sub-box body; 11 - box body; 1a - motor; 1b - controller

[0070] 20-battery module;

[0071] 30 - battery cell; 31 - housing; 311 - shell; 312 - end cap; 32 - electrode assembly; 321 - electrode body; 322 - tab; 33 - electrode terminal; 34 - pole piece; 34a - arc segment; 34b - straight segment; 341 - functional portion; 341a - base region; 341b - first skived region; 3411b - tab lead-out sub-portion; 3412b - non-tab lead-out sub-portion; 341c - second skived region; 342 - hollow foil portion;

[0072] 40-insulating member; 40a-first subsection; 40b-second subsection; 40c-connecting section; 41-first insulating member; 42-second insulating member; 41a-first end surface; 42a-second end surface;

[0073] X-first direction; Y-second direction; Z-thickness direction. DETAILED DESCRIPTION

[0074] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0075] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0076] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0077] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0078] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0079] The term "multiple" in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0080] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0081] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is a battery module formed by arranging and securing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells using cable ties.

[0082] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0083] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0084] As an example, the battery cell assembly may also be housed in the box by directly fixing the plurality of battery cells to the box.

[0085] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0086] In some embodiments, the battery device may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0087] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0088] The battery cells may be, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, and the like.

[0089] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, located between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0090] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0091] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction Z, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0092] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, stainless steel, stainless steel, copper, aluminum, carbon electrode, carbon, nickel or titanium with a silver-plated surface may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0093] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for battery cells may also be used.

[0094] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative electrode current collector.

[0095] As an example, the negative electrode current collector can employ a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver plating surface treatment, stainless steel with a silver plating surface treatment, stainless steel, copper, aluminum, a carbon electrode, carbon, nickel, or titanium, or the like can be employed.

[0096] In some embodiments, the negative electrode current collector has two surfaces opposite in a thickness direction Z 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.

[0097] As an example, the negative electrode active material can employ a negative electrode active material for a battery cell 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, or the like. 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. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative electrode active material for a battery cell can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0098] In some embodiments, the separator is a separation film. The present application does not particularly limit the type of the separation film, and any known porous structure separation film having good chemical stability and mechanical stability can be used.

[0099] As an example, the main material of the separation film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separation film can be a single layer film or a multi-layer composite film, and is not particularly limited. When the separation film is a multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separation film can be a separate member located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes.

[0100] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, and functions to transport ions and separate the positive and negative electrodes.

[0101] In some embodiments, the electrode assembly is a jelly-roll structure. The positive electrode sheet and the negative electrode sheet are wound to form the jelly-roll structure.

[0102] In some embodiments, the electrode assembly is a stack structure.

[0103] In some embodiments, the battery cell can include a shell. The shell is used to encapsulate components such as the electrode assembly and the electrolyte. The shell 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.

[0104] In some embodiments, the shell includes an end cap and a shell body, the shell body is provided with an opening, and the end cap closes the opening to form a sealed space for accommodating the electrode assembly and the electrolyte and the like. The shell body can be provided with one or more openings. The end cap can also be provided with one or more openings.

[0105] In some embodiments, at least one electrode terminal is provided on the shell, and the electrode terminal is electrically connected to the tab of the electrode assembly. The electrode terminal can be directly connected to the tab or indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the shell body.

[0106] In some embodiments, an explosion-proof valve is provided on the shell. The explosion-proof valve is used to release the internal pressure of the battery cell.

[0107] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell, or other shaped battery cells, the prismatic battery cell includes a square battery cell, a blade-shaped battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, etc., and the embodiments of the present application are not particularly limited.

[0108] In the battery cell, the electrode tab generally includes a functional part coated with an active material layer and a blank foil part not coated with the active material layer, and the end of the functional part generally has burrs. Therefore, in order to reduce the risk of burrs piercing the separator, an insulating piece is generally provided at the end of the functional part. However, the provision of the insulating piece is easy to generate a large stress on the electrode tab, thereby causing the risk of lithium precipitation of the electrode tab, and seriously affecting the reliability performance of the battery cell.

[0109] Therefore, the battery cell provided by the embodiments of the present application includes a shell, an electrode assembly, and at least one insulating piece, the electrode assembly is accommodated in the shell, the electrode tab of the electrode assembly includes a functional part coated with an active material layer and a blank foil part not coated with the active material layer, the functional part includes a base area and a first thinned area, the thickness of the first thinned area is less than the thickness of the base area, and the first thinned area is located at the end of the functional part along a first direction. The at least one insulating piece is attached to the first thinned area and beyond one end of the first thinned area away from the base area along the first direction.

[0110] The battery cell provided by the embodiments of the present application has the advantages that, by attaching the insulating piece to the first thinned area, the risk of burrs piercing the separator at the end of the functional part is reduced through the insulating piece, and the stress of the insulating piece on the functional part is also reduced, thereby reducing the problem of lithium precipitation of the electrode tab, and thus improving the reliability performance of the battery cell.

[0111] The technical solutions described in the embodiments of the present application are applicable to battery devices and electrical devices using battery devices.

[0112] The battery device disclosed in the embodiments of the present application can be used, but is not limited to, in electrical devices such as vehicles, ships, or aircraft. The battery device disclosed in the present application can be used to form a power supply system for the electrical device.

[0113] The embodiments of the present application provide an electrical device that uses a battery device as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, an electric bicycle, an electric motorcycle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0114] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0115] Please refer to Figure 1 , Figure 1 Schematic diagram of the structure of the vehicle 1 provided in an embodiment of the present application. The vehicle 1 can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, etc. A battery device 10 is provided inside the vehicle 1. The battery device 10 can be provided at the bottom, head, or tail of the vehicle 1. The battery device 10 can be used to power the vehicle 1. For example, the battery device 10 can serve as an operating power source for the vehicle 1 and can be used for the circuit system of the vehicle 1, such as for the working power requirements of the vehicle 1 during startup, navigation, and operation.

[0116] The vehicle 1 may further include a controller 1 b and a motor 1 a . The controller 1 b is used to control the battery device 10 to supply power to the motor 1 a , for example, to meet the power requirements of the vehicle 1 during startup, navigation, and driving.

[0117] In some embodiments of the present application, the battery device 10 can serve not only as an operating power source for the vehicle 1 , but also as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0118] Please refer to Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the structure of the battery device 10 provided in an embodiment of the present application. Figure 3This is a schematic diagram of the structure of the battery module 20 in the battery device 10 provided in an embodiment of the present application. The battery device 10 includes a housing 11 and a battery cell 30, with the battery cell 30 housed within the housing 11. The housing 11 is used to provide a storage space for the battery cell 30, and the housing 11 can adopt a variety of structures. In some embodiments, the housing 11 can include a first sub-housing 111 and a second sub-housing 112, which cover each other and together define a storage space for accommodating the battery cell 30. The second sub-box 112 can be a hollow structure with one end open, and the first sub-box 111 can be a plate-like structure. The first sub-box 111 covers the open side of the second sub-box 112, so that the first sub-box 111 and the second sub-box 112 jointly define a storage space; the first sub-box 111 and the second sub-box 112 can also be hollow structures with one side open, and the open side of the first sub-box 111 covers the open side of the second sub-box 112.

[0119] In the battery device 10, there may be multiple battery cells 30, which may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 30. The multiple battery cells 30 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery module 20 may be housed within the housing 11. Alternatively, the battery device 10 may comprise multiple battery cells 30 connected in series, in parallel, or in a hybrid connection to form a battery module 20, which is then connected in series, in parallel, or in a hybrid connection to form a single unit housed within the housing 11. The battery device 10 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 30.

[0120] The battery cell 30 may be a secondary battery or a primary battery; the battery cell 30 may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto.

[0121] Please refer to Figure 4 , Figure 4 Schematic diagram of the explosion structure of the battery cell 30 provided in the embodiment of the present application. Figure 4 As shown, the battery cell 30 includes a housing 31, an electrode assembly 32, and electrode terminals 33. The housing 31 includes a shell 311 and an end cap 312. The shell 311 has an opening, and the end cap 312 closes the opening to isolate the internal environment of the battery cell 30 from the external environment.

[0122] The shell 311 is a component for fitting the end cover 312 to form an internal environment of the battery cell 30, wherein the formed internal environment can be used to accommodate the electrode assembly 32, the electrolyte and other components. The shell 311 and the end cover 312 can be independent components. The shell 311 can be in various shapes and sizes. Specifically, the shape of the shell 311 can be determined according to the specific shape and size of the electrode assembly 32. The material of the shell 311 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0123] The end cover 312 refers to a component that covers the opening of the shell 311 to isolate the internal environment of the battery cell 30 from the external environment. Without limitation, the shape of the end cover 312 can be adapted to the shape of the shell 311 to fit the shell 311. Optionally, the end cover 312 can be made of a material with certain hardness and strength (such as aluminum alloy), so that the end cover 312 is not easily deformed when subjected to extrusion collision, so that the battery cell 30 can have higher structural strength, and the reliability can also be improved. The end cover 312 can be provided with functional components such as the electrode terminal 33. The electrode terminal 33 can be used to electrically connect with the electrode assembly 32 for outputting or inputting the electrical energy of the battery cell 30. The material of the end cover 312 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not specially limited in the embodiments. In some embodiments, an insulating structure can also be provided on the inner side of the end cover 312, which can be used to isolate the electrical connection components in the shell 311 from the end cover 312 to reduce the risk of short circuit. Exemplarily, the insulating structure can be plastic, rubber, etc.

[0124] The electrode assembly 32 is a component in which electrochemical reactions occur in the battery cell 30. One or more electrode assemblies 32 can be contained in the shell 311. The electrode assembly 32 is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and generally has a separator film between the positive electrode sheet and the negative electrode sheet, which is used to separate the positive electrode sheet and the negative electrode sheet to avoid internal short circuit of the positive electrode sheet and the negative electrode sheet. The positive electrode sheet and the negative electrode sheet have a part of the active material constituting the electrode body 321 of the electrode assembly 32, and each of the positive electrode sheet and the negative electrode sheet has a part without the active material constituting the tab 322. The positive electrode tab and the negative electrode tab can be located at one end of the electrode body 321 or at two ends of the electrode body 321, respectively. In the charging and discharging process of the battery cell 30, the positive active material and the negative active material react with the electrolyte, and the tab 322 is connected with the electrode terminal 33 to form a current loop.

[0125] In a first aspect, as Figure 4 、 Figure 5 and Figure 6As shown, the battery cell 30 provided in the embodiment of the present application includes a housing 31, an electrode assembly 32, and at least one insulating member 40. The electrode assembly 32 is accommodated in the housing 31. The electrode sheet 34 of the electrode assembly 32 includes a functional portion 341 coated with an active material layer and a hollow foil portion 342 not coated with an active material layer. The functional portion 341 includes a base region 341a and a first skived region 341b. The thickness of the first skived region 341b is less than that of the base region 341a. The first skived region 341b is located at the end of the functional portion 341 along the first direction X. The at least one insulating member 40 is attached to the first skived region 341b and extends beyond the end of the first skived region 341b facing away from the base region 341a along the first direction X.

[0126] The battery cell 30 includes an electrode assembly 32, which includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive and negative electrode sheets. The electrode sheet 34 can be a positive electrode sheet, or it can also be a negative electrode sheet, or it can be both a positive electrode sheet and a negative electrode sheet. In other words, only the positive electrode sheet can have the first thinned region 341b, or only the negative electrode sheet can have the first thinned region 341b, or both the positive electrode sheet and the negative electrode sheet can have the first thinned region 341b. Therefore, the insulating member 40 can be disposed only in the first thinned region 341b of the positive electrode sheet, or only in the first thinned region 341b of the negative electrode sheet, or the insulating member 40 can be disposed in the first thinned region 341b of both the positive electrode sheet and the negative electrode sheet.

[0127] The electrode piece 34 includes a functional portion 341 and a hollow foil portion 342. The electrode piece 34 may have one or two hollow foil portions 342, which are respectively provided at opposite ends of the functional portion 341. The hollow foil portions 342 may be formed into the tabs 322 of the electrode assembly 32 through a shaping process.

[0128] The functional portion 341 includes a base region 341a and a first thinned region 341b. The thickness of the first thinned region 341b is smaller than that of the base region 341a. The thickness of the active material layer coated on the first thinned region 341b can be smaller than that of the active material layer coated on the base region 341a.

[0129] Alternatively, the electrode assembly 32 may be in a wound shape, or in a laminated shape. Alternatively, the battery cell 30 may be in a cylindrical or polygonal shape.

[0130] In the embodiment in which the electrode assembly 32 is in a wound shape, the first direction X can be a winding direction of the electrode sheet 34, or the first direction X can be a direction of the empty foil portion 342 with respect to the functional portion 341. That is, the first thinned region 341b can be provided at an end of the functional portion 341 in the winding direction, or the first thinned region 341b can be provided at an end of the functional portion 341 close to or away from the empty foil portion 342.

[0131] In the embodiment in which the electrode assembly 32 is in a stacked shape, the electrode sheet 34 can be in a sheet shape, the first thinned region 341b can be provided at one side of the functional portion 341 toward or away from the empty foil portion 342, or the first thinned region 341b can be provided at an end of the functional portion 341 perpendicular to a thickness of the electrode sheet 34 and a direction of arrangement of the functional portion 341 and the empty foil portion 342.

[0132] Optionally, one electrode sheet 34 can have one, two, or more first thinned regions 341b.

[0133] Optionally, the battery cell 30 can include one insulating member 40, or the battery cell 30 can include two or more insulating members 40, one first thinned region 341b can be provided with one or more insulating members 40, and exemplarily, one insulating member 40 can be provided at each of two sides of the first thinned region 341b in the thickness direction Z.

[0134] The insulating member 40 is attached to the first thinned region 341b, and optionally, the insulating member 40 can be attached to either side of the first thinned region 341b in the thickness direction Z, or the insulating member 40 can be attached to both sides of the first thinned region 341b in the thickness direction Z. When the insulating member 40 extends beyond the first thinned region 341b on a side of the first thinned region 341b away from the base region 341a in the first direction X, the insulating member 40 can provide protection to the side of the first thinned region 341b away from the base region 341a, so as to reduce the risk of burrs on the side of the first thinned region 341b away from the base region 341a puncturing the separator, and thus reduce the risk of internal short circuit of the electrode assembly 32.

[0135] The insulating member 40 is attached to the first thinned region 341b, and optionally, the insulating member 40 can cover a part of the first thinned region 341b, or the insulating member 40 can cover the entire first thinned region 341b. The insulating member 40 can not cover any part of the base region 341a, or the insulating member 40 can cover a part of the base region 341a.

[0136] Optionally, the insulating member 40 can be attached to the first thinned region 341b by means of adhesion, or the insulating member 40 can be attached to the first thinned region 341b only by means of extrusion force, and the specific attachment method can be selected according to actual needs.

[0137] Since the thickness of the first thinned area 341b is smaller than the thickness of the base area 341a, after the electrode assembly 32 is formed, there is a larger space between the first thinned area 341b and the adjacent electrode piece 34. The insulating member 40 is attached to the first thinned area 341b, and the step at the end of the insulating member 40 is located in the larger space corresponding to the first thinned area 341b. This is beneficial to reducing the stress of the end of the insulating member 40 on the functional part 341, and further beneficial to reducing the risk of lithium deposition in the functional part 341.

[0138] The battery cell 30 provided in the embodiment of the present application, by attaching the insulating part 40 to the first thinned area 341b, is beneficial to reducing the stress of the insulating part 40 on the functional part 341 while reducing the risk of burrs at the end of the functional part 341 damaging the diaphragm through the insulating part 40, thereby helping to reduce the problem of lithium plating of the pole piece 34, thereby helping to improve the reliability performance of the battery cell 30.

[0139] In some embodiments, as Figure 5 and Figure 6 As shown, the insulating member 40 has a first end surface 41 a, which is located at one end of the insulating member 40 along the first direction X. Along the thickness direction Z of the functional portion 341, at least part of the orthographic projection of the first end surface 41 a is located in the first thinned area 341 b.

[0140] Optionally, an insulating member 40 may have a first end face 41a, and the other end face is arranged beyond the functional portion 341 along the first direction X; or, an insulating member 40 may have two first end faces 41a. In this case, the insulating member 40 can be folded, and the two first end faces 41a of the folded insulating member 40 are respectively located on both sides of the first thinning area 341b along the thickness direction Z.

[0141] At least part of the positive projection of the first end face 41a is located in the first thinning area 341b, then at least part of the first end face 41a of the insulating member 40 along the first direction X is located in the first thinning area 341b. Since the thickness of the first thinning area 341b is less than the thickness of the base area 341a, the step formed by the first end face 41a of the insulating member 40 in the first thinning area 341b is smaller, and the stress on the first thinning area 341b is smaller, which is beneficial to further reduce the stress of the end of the insulating member 40 on the functional part 341, and further beneficial to reduce the risk of lithium deposition on the pole piece 34.

[0142] In some embodiments, as Figure 5 and Figure 7As shown, at least one insulating member 40 includes at least two insulating members 40, and the at least two insulating members 40 include a first insulating member 41 and a second insulating member 42. The first insulating member 41 and the second insulating member 42 are respectively arranged on both sides of the first thinning area 341b along the thickness direction Z of the functional part 341, and the parts of the first insulating member 41 and the second insulating member 42 that exceed the functional part 341 are fitted to each other.

[0143] In this way, the two insulating parts 40 are respectively arranged on both sides of the same first thinned area 341b along the thickness direction Z, and the two sides of the first thinned area 341b protect the end of the functional part 341 along the first direction X, which is beneficial to further reduce the risk of burrs on the functional part 341 damaging the diaphragm.

[0144] Therefore, the first insulating member 41 and the second insulating member 42 cover the ends of the first thinned area 341b on both sides along the thickness direction Z to reduce the risk of burrs at the ends of the functional part 341 piercing the diaphragm or the electrode piece 34, thereby reducing the risk of internal short circuit in the electrode assembly 32.

[0145] In some embodiments, as Figure 5 and Figure 7 As shown, the insulating member 40 has a first end surface 41a. The first end surface 41a is located at one end of the insulating member 40 along the first direction X. The orthographic projection of the first end surface 41a along the thickness direction Z of the functional portion 341 is located within the functional portion 341. The first end surface 41a of the first insulating member 41 and the first end surface 41a of the second insulating member 42 are staggered along the thickness direction Z.

[0146] The orthographic projection of the first end surface 41a along the thickness direction Z is located in the functional portion 341 . Optionally, the orthographic projection of the first end surface 41a along the thickness direction Z may be located in the base region 341a or in the first thinned region 341b .

[0147] The first end surface 41 a of the first insulating member 41 and the first end surface 41 a of the second insulating member 42 are staggered along the thickness direction Z. The first end surface 41 a of the first insulating member 41 and the first end surface 41 a of the second insulating member 42 are respectively arranged at an orthographic projection interval of the functional portion 341 .

[0148] This helps reduce the size of the step generated by the first end face 41a of the first insulating member 41 and the first end face 41a of the second insulating member 42 in the functional portion 341, further reduces the stress of the insulating member 40 on the pole piece 34, and thus helps reduce the risk of lithium deposition in the pole piece 34.

[0149] In some embodiments, as Figure 5 and Figure 8As shown, the insulating member 40 includes a first subsegment 40a, a second subsegment 40b, and a connecting segment 40c. The first subsegment 40a and the second subsegment 40b are respectively disposed on opposite sides of the functional portion 341 along its thickness direction Z. The connecting segment 40c connects the first subsegment 40a and the second subsegment 40b. The first subsegment 40a has a first end surface 41a, which is located at the end of the first subsegment 40a facing away from the connecting segment 40c. The second subsegment 40b has a second end surface 42a, which is located at the end of the second subsegment 40b facing away from the connecting segment 40c. The first end surface 41a and the second end surface 42a are offset along the thickness direction Z.

[0150] The first sub-segment 40 a , the second sub-segment 40 b and the connecting segment 40 c may be integrally formed, which is beneficial for reducing the amount of the insulating member 40 used and simplifying the structure of the electrode assembly 32 .

[0151] Specifically, an insulating member 40 can be folded and attached to both sides of the first thinned area 341b. In this way, the insulating member 40 has a certain covering effect on the side of the first thinned area 341b facing away from the base area 341a, which can reduce the risk of burrs at the end of the first thinned area 341b piercing the diaphragm or the electrode 34, thereby reducing the risk of internal short circuit of the electrode assembly 32.

[0152] The first end face 41a of the first sub-segment 40a and the second end face 42a of the second sub-segment 40b are staggered along the thickness direction Z. Therefore, the orthographic projections of the first end face 41a and the second end face 42a on the functional portion 341 along the thickness direction Z are staggered. This helps to reduce the step size of the insulating member 40 on both sides of the functional portion 341, thereby reducing the stress of the insulating member 40 on the functional portion 341.

[0153] Therefore, the insulating part 40 is provided to include a first sub-segment 40a, a second sub-segment 40b and a connecting segment 40c, and the first end face 41a and the second end face 42a are provided to be staggered along the thickness direction Z. This is beneficial to reducing the risk of burrs at the end of the first thinning area 341b puncturing the diaphragm, and an insulating part 40 can be folded and respectively attached to both sides of the first thinning area 341b, which is also beneficial to simplifying the structure of the electrode assembly 32 and reducing the stress of the insulating part 40 on the functional part 341 of the electrode 34, thereby further reducing the risk of lithium deposition in the electrode 34.

[0154] In some embodiments, please refer to Figure 5 and Figure 8 , at least part of the orthographic projection of the first end face 41a along the thickness direction Z is located inside the first thinning zone 341b; and / or, at least part of the orthographic projection of the second end face 42a along the thickness direction Z is located inside the first thinning zone 341b.

[0155] At least part of the projection of the first end surface 41a along the thickness direction Z is located inside the first thinned region 341b. Optionally, the projection of the first end surface 41a along the thickness direction Z can be entirely located inside the first thinned region 341b. At least part of the first end surface 41a is arranged correspondingly to the first thinned region 341b. Since the thickness of the first thinned region 341b is small, the size of the step of the first end surface 41a at the functional portion 341 is reduced, the stress of the insulating member 40 on the functional portion 341 is further reduced, and the risk of lithium precipitation of the pole piece 34 is further reduced.

[0156] Similarly, at least part of the projection of the second end surface 42a along the thickness direction Z is located inside the first thinned region 341b. Optionally, the projection of the second end surface 42a along the thickness direction Z can be entirely located inside the first thinned region 341b. At least part of the second end surface 42a is arranged correspondingly to the first thinned region 341b, which is beneficial to reduce the size of the step of the second end surface 42a at the functional portion 341, further reduce the stress of the insulating member 40 on the functional portion 341, and further reduce the risk of lithium precipitation of the pole piece 34.

[0157] Therefore, the size of the step of the first end surface 41a and / or the second end surface 42a at the functional portion 341 is reduced, the stress of the insulating member 40 on the functional portion 341 is further reduced, and the risk of lithium precipitation of the pole piece 34 is further reduced.

[0158] In some embodiments, the electrode assembly 32 includes a positive pole piece, and the pole piece 34 is the positive pole piece.

[0159] Compared with the negative pole piece, the thickness of the positive pole piece is usually higher, and during charging, lithium ions are released from the positive pole piece and embedded in the negative pole piece. Therefore, more negative pole pieces are needed to receive the lithium ions released from the positive pole piece.

[0160] Therefore, the positive pole piece is provided with the first thinned region 341b, which is beneficial to reduce the risk that the lithium ions released from the positive pole piece cannot be received by the negative pole piece, and is beneficial to reduce the stress of the insulating member 40 on the positive pole piece, and further beneficial to reduce the risk of lithium precipitation of the electrode assembly 32.

[0161] In some embodiments, the surface of the first thinned region 341b towards the side of the insulating member 40 is flat, arc-shaped, or stepped.

[0162] In this way, the stress of the insulating member 40 on the pole piece 34 of the first thinned region 341b is reduced, and the manufacturing of the thinned region is facilitated.

[0163] In some embodiments, as Figure 5 , Figure 6 , Figure 7 and Figure 8As shown, the thickness of the first thinned region 341 b tends to decrease from one end of the first thinned region 341 b toward the base region 341 a to the other end facing away from the base region 341 a .

[0164] Optionally, the surface of the first thinned area 341 b may be straight, arc-shaped, or stepped.

[0165] In this way, the manufacturing of the first thinned area 341 b is facilitated while reducing the stress of the insulating member 40 on the pole piece 34 .

[0166] In some embodiments, as Figure 9 and Figure 14 As shown, the first thinned areas 341 b are provided at both ends of the base area 341 a along the first direction X, and at least two insulating members 40 are respectively provided at the first thinned areas 341 b at both ends of the functional portion 341 along the first direction X.

[0167] In this way, the risk of burrs at both ends of the functional part 341 of the pole piece 34 along the first direction X damaging the diaphragm can be reduced, and the stress of the insulating part 40 on the first thinned area 341b at both ends of the functional part 341 along the first direction X can be reduced, which is conducive to further reducing the risk of lithium deposition in the pole piece 34.

[0168] In some embodiments, as Figure 5 As shown, the hollow foil portion 342 is provided at the end of the functional portion 341 along the second direction Y, and the first direction X and the second direction Y intersect.

[0169] The first direction X and the second direction Y intersect. For example, the first direction X may be perpendicular to the second direction Y. For a wound electrode assembly 32 , the first direction X may be the winding direction of the electrode assembly 32 .

[0170] The hollow foil portion 342 may be the tab 322 of the electrode assembly 32 , which is extended in the second direction Y. This helps reduce stress at the end of the electrode piece 34 in a direction intersecting with the extension direction of the tab 322 .

[0171] In some embodiments, as Figure 10 As shown, the pole piece 34 is wound along the first direction X, and the first thinned area 341b is provided at the innermost end of the base area 341a, and / or the first thinned area 341b is provided at the outermost end of the base area 341a.

[0172] In this way, the first direction X is the winding direction of the electrode assembly 32. The first thinned region 341b can be provided at the innermost end of the base region 341a, or at the outermost end of the base region 341a. Of course, the first thinned region 341b can also be provided at both the innermost and outermost ends of the base region 341a along the winding direction. In this way, the insulating member 40 can be provided at the outermost end of the pole piece 34, or at the innermost end of the pole piece 34, or at both the innermost and outermost ends of the pole piece 34.

[0173] Therefore, with such a configuration, the first thinning area 341b can be the starting end or the ending end of the winding of the pole piece 34, so as to protect the starting end and / or the ending end of the winding of the pole piece 34, respectively, and reduce the risk of burrs at the ending end and / or the starting end of the pole piece 34 damaging the pole piece 34.

[0174] In some embodiments, as Figure 10 As shown, the pole piece 34 includes arc segments 34 a and straight segments 34 b alternately arranged along the first direction X, and the first thinned area 341 b is located in the arc segment 34 a.

[0175] The pole piece 34 is wound into a polygonal column shape, and there is a larger space between the arc segments 34a of the pole piece 34. A first thinned area 341b is set in the arc segment 34a. Since the insulating member 40 is attached to the arc segment 34a, the insulating member 40 is set between the arc segments 34a of the pole piece 34, which is beneficial to reducing the stress of the insulating member 40 on the first thinned area 341b.

[0176] Therefore, the first thinning area 341b is set in the arc segment 34a. The gap between the pole pieces 34 of the arc segment 34a is larger, and there is more space to accommodate the insulating part 40, which is beneficial to reducing the stress of the insulating part 40 on the functional part 341, and further beneficial to reducing the risk of lithium deposition of the pole piece 34.

[0177] In some embodiments, the functional portion 341 is stacked along its thickness direction Z, and the first direction X, the second direction Y, and the thickness direction Z are perpendicular to each other.

[0178] In this way, the electrode assembly 32 is in a stacked shape. Since the hollow foil portion 342 is located at the end of the functional portion 341 along the second direction Y, the pole tab 322 of the electrode assembly 32 is led out from the end of the functional portion 341 in the second direction Y. The first direction X, the second direction Y and the thickness direction Z are perpendicular to each other, and the first thinning area 341b is located in the direction where the functional portion 341 and the pole tab 322 are led out. In this way, the insulating part 40 is arranged in the direction where the functional portion 341 and the pole tab 322 are led out, which is beneficial to reducing the risk of burrs at the end of the functional portion 341 along the second direction Y damaging the diaphragm.

[0179] Therefore, with such a configuration, the electrode assembly 32 is arranged in a stacked form, which facilitates the preparation of the electrode assembly 32, and the insulating member 40 can be used to protect at least one end of the electrode piece 34 along the first direction X, thereby reducing the risk of burrs at the end of the electrode piece 34 along the first direction X piercing the diaphragm.

[0180] In some embodiments, as Figure 5 As shown, along the second direction Y, at least one end of the insulating member 40 is disposed beyond the functional portion 341 .

[0181] The end of the functional part 341 along the second direction Y may also have burrs. If the end of the insulating part 40 along the second direction Y is arranged to extend beyond the functional part 341, the same insulating part 40 can protect the end of the functional part 341 along the first direction X and the end along the second direction Y, so as to reduce the risk of the burrs at the end of the functional part 341 along the first direction X and the end along the second direction Y damaging the diaphragm.

[0182] Therefore, such a configuration is beneficial to further reduce the risk of burrs at the ends of the functional portion 341 along the first direction X and along the second direction Y piercing the diaphragm, and further beneficial to reduce the risk of internal short circuit of the electrode assembly 32.

[0183] In some embodiments, along the second direction Y, the insulating member 40 is disposed beyond the hollow foil portion 342 .

[0184] After the electrode assembly 32 is manufactured, it is necessary to inspect the electrode assembly 32 to confirm whether the insulating part 40 is missing from the electrode assembly 32. Therefore, the insulating part 40 is set beyond the empty foil portion 342 along the second direction Y, which is convenient for detecting whether the insulating part 40 is set or not, which is beneficial to improving product yield.

[0185] In some embodiments, the electrode assembly 32 includes a positive electrode sheet, a negative electrode sheet, and a separator. The separator is disposed between the positive electrode sheet and the negative electrode sheet, and the insulating member 40 extends beyond at least one end of the separator along the second direction Y.

[0186] The second direction Y is the lead-out direction of the tab 322 . The insulating member 40 is arranged to extend beyond the diaphragm along the second direction Y, which facilitates detection of whether the insulating member 40 is provided, thereby improving product yield.

[0187] In some embodiments, as Figure 12 As shown, the functional portion 341 also includes a second thinning area 341c, which is arranged at the end of the base area 341a along the second direction Y. At least one insulating member 40 is attached to the second thinning area 341c and extends along the second direction Y beyond the second thinning area 341c to one end facing away from the base area 341a.

[0188] The first thinning area 341b is arranged at the end of the functional part 341 along the first direction X, and the second thinning area 341c is arranged at the end of the functional part 341 along the second direction Y, and the insulating member 40 is arranged on both the first thinning area 341b and the second thinning area 341c, which is conducive to reducing the risk of burr of the functional part 341 along the first direction X and the second direction Y end of the diaphragm by the insulating member 40, and conducive to reducing the stress of the insulating member 40 on the first thinning area 341b and the second thinning area 341c of the functional part 341, so as to reduce the stress of the insulating member 40 on the functional part 341, and further reduce the risk of lithium precipitation of the pole piece 34. The insulating member 40 is arranged beyond at least one end of the diaphragm along the second direction Y,

[0189] In some embodiments, as shown in Figure 10 The empty foil part 342 is arranged at the end of the functional part 341 along the first direction X.

[0190] In this way, the tab 322 of the electrode assembly 32 is led out by the first direction X, and the insulating member 40 is arranged on the side of the functional part 341 close to the tab 322, which is conducive to reducing the risk of burr of the functional part 341 to the tab 322 and the diaphragm, and conducive to reducing the risk of lithium precipitation at the end of the pole piece 34 along the first direction X.

[0191] In some embodiments, as shown in Figure 13 The empty foil part 342 includes the tabs 322 arranged at intervals, the first thinning area 341b includes the tab leading-out sub-part 3411b and the non-tab leading-out sub-part 3412b, the tabs 322 are only led out by the tab leading-out sub-part 3411b, and the insulating member 40 is arranged on at least part of the non-tab leading-out sub-part 3412b.

[0192] In this way, the insulating member covers at least part of the non-tab leading-out sub-part 3412b, which is conducive to reducing the risk of burr of the non-tab leading-out sub-part 3412b to the diaphragm and causing internal short circuit of the battery monomer 30.

[0193] In a second aspect, the present application provides a battery device 10, which includes the battery device 10 provided by any of the above embodiments.

[0194] The battery device 10 provided by the embodiments of the present application has the same technical effects as the battery monomer 30 provided by any of the above embodiments.

[0195] In a third aspect, the present application provides a power consumption device, which includes the battery device 10 provided by the above embodiments, and the battery device 10 is used to provide electric energy.

[0196] The power consumption device provided by the embodiments of the present application has the same technical effects as the battery device 10 provided by the above embodiments.

[0197] In some embodiments, as shown in Figures 4 to 14 the battery cell 30 includes a housing 31, an electrode assembly 32 accommodated in the housing 31, and at least one insulating member 40. The positive electrode tab of the electrode assembly 32 includes a functional portion 341 coated with an active material layer and a blank foil portion 342 not coated with an active material layer. The functional portion 341 includes a base region 341a and a first thinned region 341b having a thickness smaller than that of the base region 341a. The first thinned region 341b is located at an end of the functional portion 341 along a first direction X. The blank foil portion 342 is provided at an end of the functional portion 341 along a second direction Y intersecting the first direction X. The electrode assembly 32 has a wound shape, and the first direction X is a winding direction of the electrode assembly 32. The at least two insulating members 40 include a first insulating member 41 and a second insulating member 42. The first insulating member 41 and the second insulating member 42 are respectively attached to both sides of the first thinned region 341b along a thickness direction Z and extend beyond the first thinned region 341b on a side opposite to the base region 341a along the first direction X. The portions of the first insulating member 41 and the second insulating member 42 extending beyond the functional portion 341 are attached to each other. The insulating member 40 has a first end surface 41a located at one end of the insulating member 40 along the first direction X. The first end surface 41a has a normal projection located within the first thinned region 341b along the thickness direction Z of the functional portion 341. The first end surface 41a of the first insulating member 41 and the first end surface 41a of the second insulating member 42 are arranged staggered along the thickness direction Z. The surface of the first thinned region 341b on the side facing the insulating member 40 has a flat shape, an arc shape, or a stepped shape. The thickness of the first thinned region 341b has a decreasing trend from the end of the first thinned region 341b facing the base region 341a to the end of the first thinned region 341b opposite to the base region 341a. The positive electrode tab includes arc-shaped segments 34a and flat segments 34b arranged alternately along the first direction X, and the first thinned region 341b is provided in the arc-shaped segments 34a.

[0198] Although the present application has been described with reference to the preferred embodiments, various modifications are possible in the light of the above teachings. Moreover, the metes and bounds of the present application are not to be understood as being limited to the particular embodiments disclosed in the specification, but determined by the appended claims.

Claims

1. A battery cell, characterized in that: include: shell; an electrode assembly housed in the housing, wherein the electrode assembly includes a functional portion coated with an active material layer and a hollow foil portion not coated with the active material layer, wherein the functional portion includes a base region and a first thinned region, wherein the thickness of the first thinned region is less than that of the base region, and the first thinned region is located at an end of the functional portion along a first direction; At least one insulating member is disposed on the first thinned area and extends beyond the first thinned area along the first direction to an end facing away from the base area.

2. The battery cell according to claim 1, wherein: The insulating member has a first end surface, which is located at one end of the insulating member along the first direction. Along the thickness direction of the functional portion, at least a portion of an orthographic projection of the first end surface is located within the first thinned region.

3. The battery cell according to claim 1, wherein: At least one of the insulating parts includes at least two insulating parts, and the at least two insulating parts include a first insulating part and a second insulating part. The first insulating part and the second insulating part are respectively arranged on both sides of the first thinning area along the thickness direction of the functional part, and the parts of the first insulating part and the second insulating part that exceed the functional part are in contact with each other.

4. The battery cell according to claim 3, characterized in that The insulating member has a first end surface, the first end surface is located at one end of the insulating member along the first direction, and an orthographic projection of the first end surface along the thickness direction of the functional portion is located inside the functional portion; The first end surface of the first insulating member and the first end surface of the second insulating member are staggered along the thickness direction.

5. The battery cell according to claim 1, characterized in that The insulating member includes a first sub-segment, a second sub-segment, and a connecting segment. The first sub-segment and the second sub-segment are respectively provided on both sides of the functional portion along its thickness direction. The connecting segment connects the first sub-segment and the second sub-segment. The first sub-segment has a first end face, which is located at an end of the first sub-segment facing away from the connecting segment; the second sub-segment has a second end face, which is located at an end of the second sub-segment facing away from the connecting segment, and the first end face and the second end face are staggered along the thickness direction.

6. The battery cell according to claim 5, characterized in that At least part of the orthographic projection of the first end surface along the thickness direction is located inside the first thinning zone; and / or at least part of the orthographic projection of the second end surface along the thickness direction is located inside the first thinning zone.

7. The battery cell according to claim 1, characterized in that The electrode assembly includes a positive electrode sheet, and the electrode sheet is the positive electrode sheet.

8. The battery cell according to claim 1, wherein: A surface of the first thinned area facing the insulating member is straight, arc-shaped or stepped.

9. The battery cell according to claim 8, characterized in that The thickness of the first thinned region tends to decrease from one end of the first thinned region facing the base region to the other end facing away from the base region.

10. The battery cell according to claim 1, characterized in that The first thinned regions are provided at two ends of the base region along the first direction, and at least two insulating members are respectively provided at the first thinned regions at two ends of the functional portion along the first direction.

11. The battery cell according to any one of claims 1 to 10, characterized in that: The hollow foil portion is provided at an end portion of the functional portion along a second direction, and the first direction intersects with the second direction.

12. The battery cell according to claim 11, characterized in that The pole piece is wound along the first direction, and the first thinning area is provided at the end of the innermost circle of the base area, and / or the first thinning area is provided at the end of the outermost circle of the base area.

13. The battery cell according to claim 12, characterized in that: The pole piece includes arc segments and straight segments alternately arranged along the first direction, and the first thinned area is located in the arc segments.

14. The battery cell according to claim 11, characterized in that The functional parts are stacked along their thickness direction, and the first direction, the second direction and the thickness direction are perpendicular to each other.

15. The battery cell according to claim 11, characterized in that Along the second direction, at least one end of the insulating member is disposed beyond the functional portion.

16. The battery cell according to claim 15, characterized in that Along the second direction, the insulating member is disposed beyond the hollow foil portion.

17. The battery cell according to claim 11, characterized in that The electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator. The separator is disposed between the positive electrode sheet and the negative electrode sheet. The insulating member extends beyond at least one end of the separator along the second direction.

18. The battery cell according to claim 11, characterized in that The functional portion further includes a second thinned area, which is arranged at the end of the base area along the second direction. At least one insulating member is attached to the second thinned area and extends beyond the second thinned area along the second direction toward one end of the base area.

19. The battery cell according to any one of claims 1 to 10, characterized in that: The hollow foil portion is provided at an end portion of the functional portion along the first direction.

20. The battery cell according to claim 19, characterized in that The hollow foil portion includes tabs arranged at intervals, the first thinned area includes a tab lead-out sub-portion and a non-tab lead-out sub-portion, the tab is only led out from the tab lead-out sub-portion, and the insulating member is provided on at least a portion of the non-tab lead-out sub-portion.

21. A battery device, characterized in that: Comprising the battery device according to any one of claims 1 to 20.

22. An electrical device, characterized in that: The battery device of claim 21 is provided for providing electrical energy.

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