Battery cell, battery and electric device

Abstract

The invention discloses a battery monomer, a battery and a power utilization device. The battery monomer comprises a shell, an electrode assembly, a current collecting assembly and an anti-oxidation layer, the shell has an accommodating cavity. The electrode assembly is arranged in the containing cavity. And the current collecting assembly is connected with the electrode assembly and is connected to one side, facing the accommodating cavity, of the shell. The anti-oxidation layer is arranged on the side, away from the containing cavity, of the shell, and the orthographic projection of the anti-oxidation layer on the shell and the orthographic projection of the current collecting assembly on the shell are at least partially overlapped. The current collecting assembly is arranged in the shell and connected with the electrode assembly, the electrode assembly is electrically connected with external equipment, and transmission of electric energy is achieved. And the anti-oxidation layer is arranged at the joint of the current collecting assembly and the shell, so that the risks of cracks and liquid leakage caused by corrosion due to contact between the joint of the current collecting assembly and the shell and moisture and oxygen in air can be reduced, the overall structural strength of the shell is improved, and the operation reliability of the battery monomer is improved.

Description

Battery cells, batteries, and electrical devices

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202323248857.9, filed on November 29, 2023, entitled “Battery Cell, Battery, and Electrical Device,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of batteries, and in particular to a battery cell, a battery, and an electrical device. Background Art

[0004] Battery cells are widely used in electronic devices such as mobile phones, laptops, electric bicycles, electric cars, electric airplanes, electric boats, electric toy cars, electric toy boats, electric toy airplanes, power tools, and energy storage systems. Battery cells can include nickel-cadmium battery cells, nickel-metal hydride battery cells, lithium-ion battery cells, sodium-ion battery cells, and secondary alkaline zinc-manganese battery cells.

[0005] With the development of new energy technologies, how to improve the structural stability of battery cell shells, thereby improving the reliability of battery cells, is also one of the research focuses in this field.

[0006] Summary of the Invention

[0007] In view of the above problems, the present application provides a battery cell, a battery, and an electrical device, which can improve the structural stability of the battery cell housing, thereby improving the reliability of the battery cell.

[0008] In a first aspect, the present application provides a battery cell comprising a housing, an electrode assembly, a current collector assembly, and an anti-oxidation layer. The housing has a receiving cavity. The electrode assembly is disposed within the receiving cavity. The current collector assembly is connected to the electrode assembly and is connected to a side of the housing facing the receiving cavity. The anti-oxidation layer is disposed on a side of the housing facing away from the receiving cavity, with the orthographic projection of the anti-oxidation layer on the housing at least partially overlapping with the orthographic projection of the current collector assembly on the housing.

[0009] In the technical solution of the embodiments of this application, a current collector assembly is provided within the housing, connected to the electrode assembly, electrically connecting the electrode assembly to external devices to achieve electrical energy transmission. An anti-oxidation layer is provided at the junction between the current collector assembly and the housing. This layer reduces the risk of corrosion at the junction due to contact with moisture and oxygen in the air, which could lead to cracks and leakage. This layer improves the overall structural strength of the housing and enhances the reliability of the battery cell operation.

[0010] In some embodiments, the current collecting assembly includes a current collecting disc and a first welding portion. The edge of the current collecting disc is connected to the side of the shell facing the accommodating cavity, and one side surface of the current collecting disc is connected to the pole ear of the electrode assembly. The first welding portion is provided between the current collecting disc and the shell, and is used to connect the current collecting disc and the shell. The anti-oxidation layer includes a first protective layer, and the positive projection of the first protective layer on the shell completely covers the positive projection of the first welding portion on the shell. In the above structure, the current collecting disc is provided for welding with the electrode assembly to improve the connection strength between the electrode assembly and the current collecting assembly. The first welding portion connects the current collecting disc to the shell, thereby improving the connection strength between the current collecting assembly and the shell. The first protective layer covers the position where the first welding portion is connected to the shell, reducing the probability of the shell rusting due to contact with moisture and oxygen in the air at the position of the first welding portion, reducing the risk of cracks and leakage in the shell, improving the overall structural strength of the shell, and improving the reliability of the operation of the battery cell.

[0011] In some embodiments, the housing includes a shell, an end cap, and a second weld. The shell has an opening. The end cap covers the opening, and the end cap and the shell together enclose a receiving cavity. The second weld is disposed between the shell and the end cap. The anti-oxidation layer includes a second protective layer, the orthographic projection of the second protective layer on the shell completely covering the orthographic projection of the second weld on the shell.

[0012] In the above structure, the second weld connects the end cap to the housing, improving the connection strength between the two. The second protective layer covers the location where the second weld connects to the housing, reducing the probability of rusting the housing at the second weld due to contact with moisture and oxygen in the air. This reduces the risk of cracks and leakage in the housing, improves the overall structural strength of the housing, and enhances the reliability of the battery cell operation.

[0013] In some embodiments, the first protective layer and the second protective layer are integrally formed. In the above technical solution, the integral structure improves the efficiency of manufacturing the anti-oxidation layer and enhances the overall structural strength of the housing.

[0014] In some embodiments, the battery cell further includes an anti-corrosion layer disposed on a side of the shell facing away from the accommodating cavity. The anti-corrosion layer has a notch corresponding to the first weld portion or the second weld portion, and the anti-oxidation layer covers at least part of the notch.

[0015] In the above structure, the anti-corrosion layer can improve the overall structural strength and anti-corrosion performance of the shell. Providing an anti-oxidation layer at the location where the anti-corrosion layer has an opening defect can reduce the probability of the shell exposed at the gap in the anti-corrosion layer coming into contact with moisture and oxygen in the air and rusting, thereby reducing the risk of cracks and leakage in the shell, improving the overall structural strength of the shell, and improving the reliability of the battery cell operation.

[0016] In some embodiments, the anti-corrosion layer includes a nickel layer, and the outer shell is a steel or carbon steel shell. In the above structure, using nickel-plated steel or nickel-plated carbon steel to manufacture the outer shell can improve the overall structural strength of the outer shell and provide good electrical conductivity. The nickel plating layer is dense and has low porosity, which can improve the strength, hardness, and corrosion resistance of the steel or carbon steel.

[0017] In some embodiments, the anti-oxidation layer includes at least one of a polyacrylate layer, a polyurethane layer, and an epoxy resin layer. The above structure has a high connection strength with the housing, strong corrosion resistance, and is compatible with various spraying processes, thereby improving manufacturing efficiency.

[0018] In some embodiments, an insulating layer is further provided on the side of the housing facing away from the accommodating cavity. The surface of the housing facing the insulating layer is concave to form a accommodating groove, and at least a portion of the anti-oxidation layer is disposed within the accommodating groove. In this structure, the provision of the insulating layer improves the insulation performance of the housing and enhances the safety of the battery cell during operation. Furthermore, the provision of the accommodating groove on the surface of the housing to accommodate the anti-oxidation layer reduces the thickness of the anti-oxidation layer protruding from the housing surface, reduces the space occupied by the anti-oxidation layer, improves the surface flatness of the battery cell, and increases the energy density of the battery cell.

[0019] In a second aspect, the present application provides a battery comprising the battery cell in the above embodiment.

[0020] In a third aspect, the present application provides an electrical device, which includes the battery in the above embodiment, and the battery is used to provide electrical energy.

[0021] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0023] FIG1 is a schematic structural diagram of a vehicle according to an embodiment of the present application;

[0024] FIG2 is a schematic diagram of the exploded structure of a battery according to an embodiment of the present application;

[0025] FIG3 is a schematic structural diagram of a battery cell according to an embodiment of the present application;

[0026] FIG4 is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0027] FIG5 is an enlarged structural diagram of the circle A in FIG4 ;

[0028] FIG6 is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0029] FIG7 is an enlarged structural diagram of the circle B in FIG6 ;

[0030] FIG8 is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0031] FIG9 is an enlarged structural diagram of the circle C in FIG8 ;

[0032] FIG10 is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0033] FIG11 is an enlarged structural diagram of the circle D in FIG10 .

[0034] Detailed description of the accompanying drawings: 1. vehicle; 2. battery; 10. electrode assembly; 20. shell; 22. insulating layer; 23. accommodating groove; 24. upper current collecting part; 25. electrode terminal; 26. lower current collecting part; 30. end cover; 40. outer shell; 3. controller; 4. motor; 5. box; 51. first part; 52. second part; 53. accommodating space; 6. current collecting assembly; 601. current collecting plate; 602. first welding part; 603. second welding part; 7. battery cell; 8. anti-oxidation layer; 801. first protective layer; 802. second protective layer. DETAILED DESCRIPTION

[0035] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein 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 figure descriptions are intended to cover non-exclusive inclusions.

[0037] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0038] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor 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 herein may be combined with other embodiments.

[0039] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0040] In the description of the embodiments of the present application, the term "multiple" 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).

[0041] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0042] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0043] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, 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.

[0044] 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.

[0045] Please refer to Figure 1, which is a schematic diagram of the structure of the vehicle provided in some embodiments of the present application. 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 2 is provided inside the vehicle 1, and the battery 2 can be provided at the bottom, head or tail of the vehicle 1. The battery 2 can be used to power the vehicle 1. For example, the battery 2 can serve as an operating power source for the vehicle 1. The vehicle 1 can also include a controller 3 and a motor 4. The controller 3 is used to control the battery 2 to power the motor 4, for example, for starting, navigating and driving the vehicle 1.

[0046] In some embodiments of the present application, the battery 2 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 .

[0047] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0048] Please refer to Figure 2, which is an exploded view of a battery provided in some embodiments of the present application. Battery 2 includes a housing 5 and a battery cell 7, which is housed within housing 5. Housing 5 is used to accommodate battery cell 7 and can adopt a variety of structures.

[0049] In some optional embodiments, the housing 5 includes a first portion 51 and a second portion 52, which cover each other and together define a storage space 53 for accommodating the battery cells 7. The second portion 52 may be a hollow structure with one end open, and the first portion 51 may be a plate-like structure, with the first portion 51 covering the open side of the second portion 52, so that the first portion 51 and the second portion 52 together define the storage space 53. The first portion 51 and the second portion 52 may also be hollow structures with one end open, with the open side of the first portion 51 covering the open side of the second portion 52. Of course, the housing 5 formed by the first portion 51 and the second portion 52 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0050] In some embodiments, the box 5 can serve as part of the chassis structure of the vehicle 1. For example, part of the box 5 can become at least part of the floor of the vehicle 1, or part of the box 5 can become at least part of the crossbeam and longitudinal beam of the vehicle 1.

[0051] In battery 2, there may be multiple battery cells 7, which may be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections within the battery cells 7. Multiple battery cells 7 may be directly connected in series, in parallel, or in a hybrid configuration, and then the entire battery cell 7 is housed within the housing 5. Alternatively, battery 2 may be constructed by first connecting multiple battery cells 7 in series, in parallel, or in a hybrid configuration to form a battery module. The multiple battery modules are then connected in series, in parallel, or in a hybrid configuration to form a single unit, which is then housed within the housing 5. Battery 2 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 7.

[0052] Each battery cell 7 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 7 can be cylindrical, flat, rectangular, or in other shapes.

[0053] Please refer to Figure 3, which is a schematic diagram of the structure of a battery cell 7 provided in some embodiments of the present application. A battery cell 7 is the smallest unit that makes up a battery 2. As shown in Figure 3, a battery cell 7 includes a housing 40, an electrode assembly 10, and other functional components.

[0054] The outer shell 40 may include an end cap 30 and a shell 20. The end cap 30 refers to a component that covers the opening of the shell 20 to isolate the internal environment of the battery cell 7 from the external environment. Without limitation, the shape of the end cap 30 can be adapted to the shape of the shell 20 to match the shell 20. Optionally, the end cap 30 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 30 is not easily deformed when squeezed or collided, so that the battery cell 7 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 25 can be provided on the end cap 30. The electrode terminal 25 can be used to electrically connect to the electrode assembly 10 for outputting or inputting electrical energy of the battery cell 7.

[0055] In some embodiments, the end cap 30 may also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 7 reaches a threshold. The end cap 30 may also be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment of the present application does not impose any particular limitations on this. In some embodiments, an insulating component may also be provided on the inner side of the end cap 30. The insulating component may be used to isolate the electrical connection components within the housing 20 from the end cap 30 to reduce the risk of short circuits. Exemplary embodiments include plastic, rubber, etc.

[0056] The housing 20 is a component that cooperates with the end cap 30 to form the internal environment of the battery cell 7. This internal environment can be used to accommodate the electrode assembly 10, electrolyte, and other components. The housing 20 and end cap 30 can be separate components. An opening can be provided in the housing 20, and the end cap 30 can be placed over the opening to form the internal environment of the battery cell 7. Alternatively, the end cap 30 and housing 20 can be integrated. Specifically, the end cap 30 and housing 20 can form a common connection surface before other components are inserted into the housing. When the interior of the housing 20 needs to be enclosed, the end cap 30 can be placed over the housing 20. The housing 20 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the housing 20 can be determined based on the specific shape and size of the electrode assembly 10. The housing 20 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment of the present application does not impose any particular limitations on this.

[0057] The electrode assembly 10 is the component in the battery cell 7 where the electrochemical reaction occurs. One or more electrode assemblies 10 may be contained within the housing 20. The electrode assembly 10 includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell 7, active ions (such as lithium ions) are embedded in and released from the positive and negative electrodes. The separator is provided between the positive and negative electrodes to prevent short circuits between the positive and negative electrodes while allowing active ions to pass through.

[0058] In some embodiments, the separator is a separator. This application does not specifically limit the type of separator; any known porous separator with good chemical and mechanical stability can be used. For example, the separator can be made primarily of at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic.

[0059] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0060] In some embodiments, the battery cell 7 further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not specifically limit the type of electrolyte, and the electrolyte may be selected based on needs. The electrolyte may be liquid, gel, or solid.

[0061] In some embodiments, the electrode assembly 10 is a wound structure. Alternatively, the electrode assembly 10 is a laminated structure.

[0062] In some embodiments, the shape of the electrode assembly 10 can be cylindrical, flat, or polygonal.

[0063] In some embodiments, the electrode assembly 10 is provided with tabs, which can conduct current from the electrode assembly 10. The tabs include a positive tab and a negative tab.

[0064] In some embodiments, the battery cell 7 includes a current collector assembly, which is used to connect the electrode assembly 10 to the housing 20. The current collector assembly includes an upper current collector 24 and a lower current collector 26. One side of the upper current collector 24 is connected to one tab of the electrode assembly 10, and the other side is welded to the electrode terminal 25. One side of the lower current collector 26 is connected to the other tab of the electrode assembly 10, and the circumference of the lower current collector 26 is connected to the inner wall of the housing 20.

[0065] With the advancement of battery technology, the structural stability of battery cell casings has attracted attention. Because battery cell operation generates heat, metal casings exposed to air at high temperatures are susceptible to oxidation reactions with oxygen and moisture in the air, leading to oxidation and rust. Therefore, the casings are typically coated with an anti-corrosion coating before leaving the factory. This coating is applied entirely using a spray or electroplating process.

[0066] The lower current collector in a battery is typically connected to the outer shell by welding. For example, the connection between the lower current collector and the outer shell can be heated, causing a portion of the lower current collector to melt and connect to the shell. After cooling, a secure connection is formed between the lower current collector and the outer shell. However, the heating process damages the anti-oxidation coating on the outside of the outer shell. As a result, a gap forms in the anti-oxidation coating at the connection between the lower current collector and the outer shell, exposing the metal outer shell to the outside and reacting with oxygen and moisture in the air, causing oxidation and rusting of the outer shell. In the rusted area, the outer shell will crack and leak, reducing the safety of the battery cell during operation and shortening its service life.

[0067] Based on the above considerations, the present application provides a battery cell comprising a housing, an electrode assembly, a current collector assembly, and an anti-oxidation layer. The housing has a receiving cavity. The electrode assembly is disposed within the receiving cavity. The current collector assembly is connected to the electrode assembly and is connected to the side of the housing facing the receiving cavity. The anti-oxidation layer is disposed on the side of the housing facing away from the receiving cavity, with the orthographic projection of the anti-oxidation layer on the housing at least partially overlapping with the orthographic projection of the current collector assembly on the housing.

[0068] In the technical solution of the embodiments of this application, a current collector assembly is provided within the housing, connected to the electrode assembly, electrically connecting the electrode assembly to other components to achieve electrical energy transmission. An anti-oxidation layer is provided at the junction of the current collector assembly and the housing. This layer reduces the risk of corrosion at the junction due to contact with moisture and oxygen in the air, which can lead to cracks and leakage. This layer improves the overall structural strength of the housing and enhances the reliability of the battery cell operation.

[0069] As shown in Figures 4 and 5, in some embodiments of the present application, the current collecting assembly 6 includes a current collecting disc 601 and a first weld 602. The edge of the current collecting disc 601 is connected to the side of the housing 40 facing the accommodating cavity, and one side surface of the current collecting disc 601 is connected to the tab of the electrode assembly 10. The first weld 602 is provided between the current collecting disc 601 and the housing 40 and is used to connect the current collecting disc 601 and the housing 40. The anti-oxidation layer 8 includes a first protective layer 801, the orthographic projection of the first protective layer 801 on the housing 40 completely covering the orthographic projection of the first weld 602 on the housing 40.

[0070] Exemplarily, the first welding portion 602 may be formed by melting the metal at the edge of the current collecting assembly 6 at high temperature and cooling it, or the first welding portion 602 may be formed by melting the solder at high temperature and cooling it. The shape of the collecting plate 601 may match the shape of the end cover 30, and the edge of the collecting plate 601 may abut or fit against the inner wall of the outer shell 40. The orthographic projection of the first protective layer 801 on the outer shell 40 completely covers the orthographic projection of the first welding portion 602 on the outer shell 40. The orthographic projection of the first protective layer 801 on the outer shell 40 may completely overlap with the orthographic projection of the first welding portion 602 on the outer shell 40, or the orthographic projection area of ​​the first protective layer 801 on the outer shell 40 may be larger than the orthographic projection of the first welding portion 602 on the outer shell 40.

[0071] In the above structure, a current collecting plate 601 is provided for welding to the electrode assembly 10, thereby improving the connection strength between the electrode assembly 10 and the current collecting assembly 6. The first weld 602 connects the current collecting plate 601 to the outer shell 40, thereby improving the connection strength between the current collecting assembly 6 and the outer shell 40. The first protective layer 801 covers the location where the first weld 602 connects to the outer shell 40, reducing the probability of rusting of the outer shell 40 due to contact with moisture and oxygen in the air at the location of the first weld 602, reducing the risk of cracks and leakage in the outer shell 40, improving the overall structural strength of the outer shell 40, and enhancing the reliability of the operation of the battery cell 7.

[0072] As shown in Figures 6 and 7, in some optional embodiments, the first weld portion 602 can penetrate the housing 40 and extend to the side of the housing 40 facing away from the accommodating cavity. In the above structure, the first weld portion 602 penetrates the housing 40, which can improve the strength of the connection between the collecting plate 601 and the housing 40.

[0073] As shown in Figures 8 and 9, in some embodiments of the present application, the housing 40 includes a shell 20, an end cap 30, and a second weld 603. The shell 20 has an opening. The end cap 30 covers the opening, and the end cap 30 and the shell 20 together form a receiving cavity. The second weld 603 is disposed between the shell 20 and the end cap 30. The anti-oxidation layer 8 includes a second protective layer 802, the orthographic projection of the second protective layer 802 on the shell 40 completely covering the orthographic projection of the second weld 603 on the shell 40.

[0074] In the above structure, the second weld 603 connects the end cap 30 to the housing 20, improving the connection strength between the end cap 30 and the housing 20. The second protective layer 802 covers the location where the second weld 603 connects to the housing 40, reducing the probability of rusting of the housing 40 due to contact with moisture and oxygen in the air at the second weld 603, reducing the risk of cracks and leakage in the housing 40, improving the overall structural strength of the housing 40, and enhancing the operational reliability of the battery cell 7.

[0075] In some embodiments of the present application, the first protective layer 801 and the second protective layer 802 are integrally formed. In the above technical solution, the first protective layer 801 and the second protective layer 802 are connected as an integral structure, which improves the efficiency of manufacturing the anti-oxidation layer 8 and enhances the overall structural strength of the housing 40.

[0076] In some embodiments of the present application, the battery cell 7 further includes an anti-corrosion layer disposed on the side of the shell 40 facing away from the accommodating cavity. The anti-corrosion layer has a notch corresponding to the position of the first welding portion 602 or the second welding portion 603 , and the anti-oxidation layer 8 covers at least part of the notch.

[0077] Exemplarily, the anti-corrosion coating is directly sprayed or electroplated on the surface of the metal shell 40 when the shell 40 leaves the factory, which is used to protect the metal shell 40, prevent it from oxidation and improve its surface strength. However, during the manufacturing process of the battery cell 7, the positions of the first welding part 602 and the second welding part 603 need to be heated to connect the shell 20 to the collecting plate 601 and the end cover 30. The anti-corrosion layer at the above-mentioned position will be damaged by the high temperature to form a gap. Therefore, an anti-oxidation layer 8 can be set at the above-mentioned position. Optionally, during the manufacturing process of the shell 20, scratches or collisions may occur, causing the anti-corrosion layer to be damaged and form a gap. An anti-oxidation layer 8 can also be set at the above-mentioned position. It is understandable that the thickness of the anti-corrosion layer at the gap is less than the thickness of the anti-corrosion layer in other areas of the shell 20. Providing an anti-oxidation layer 8 at the above-mentioned position can reduce the probability of rust on the metal shell 20 at the gap and improve the overall structural strength of the shell 20.

[0078] In the above structure, the anti-corrosion layer can improve the overall structural strength and anti-corrosion performance of the shell 40. The anti-oxidation layer 8 is set at the position where the anti-corrosion layer has defects, which can reduce the probability of the shell 40 exposed at the gap position of the anti-corrosion layer coming into contact with moisture and oxygen in the air and rusting, thereby reducing the risk of cracks and leakage in the shell 40, improving the overall structural strength of the shell 40, and improving the reliability of the operation of the battery cell 7.

[0079] For example, the shape of the anti-oxidation layer 8 can completely match the shape of the notch. Optionally, the area of ​​the anti-oxidation layer 8 is larger than the area of ​​the notch, and the edge of the anti-oxidation layer 8 forms a closed curve that completely surrounds the notch. For example, the minimum distance between the edge of the anti-oxidation layer 8 and the edge of the notch is 0.1 mm.

[0080] In some embodiments of the present application, the anti-corrosion layer includes a nickel layer, and the housing 40 is a steel housing 40 or a carbon steel housing 40. Exemplarily, the thickness of the anti-corrosion layer is 0.1 μm to 5 μm. This thickness range minimizes the overall thickness and mass of the housing 20 while improving the anti-corrosion effect.

[0081] In the above structure, the nickel plating is dense and has low porosity, which can improve the strength, hardness, and corrosion resistance of steel or carbon steel. Using nickel-plated steel or nickel-plated carbon steel to manufacture the shell 40 can improve the overall structural strength of the shell 40 and have good electrical conductivity.

[0082] In some embodiments of the present application, the anti-oxidation layer 8 comprises at least one of a polyacrylate layer, a polyurethane layer, and an epoxy resin layer. Exemplarily, the thickness of the anti-oxidation layer 8 ranges from 10 μm to 50 μm. This thickness range ensures the anti-oxidation performance of the welds of the housing 20 while reducing the overall thickness and weight of the housing 20.

[0083] In the above structure, the anti-oxidation layer 8 is made of an organic material with a viscosity in the range of 1 to 1000 cps. It has a high connection strength with the metal shell 40 and is highly corrosion-resistant. It is also suitable for various spraying processes and has high manufacturing efficiency.

[0084] As shown in Figures 10 and 11, in some embodiments of the present application, an insulating layer 22 is further provided on the side of the housing 40 facing away from the accommodating cavity. The surface of the housing 40 facing the insulating layer 22 is concave to form an accommodating groove 23, and at least a portion of the anti-oxidation layer 8 is disposed in the accommodating groove 23. In the above structure, the provision of the insulating layer 22 improves the insulation performance of the housing 40 and the safety of the battery cell 7 during operation. In addition, the provision of the accommodating groove 23 on the surface of the housing 40 to accommodate the anti-oxidation layer 8 can reduce the thickness of the anti-oxidation layer 8 protruding from the surface of the housing 40, reduce the space occupied by the anti-oxidation layer 8, improve the surface flatness of the battery cell 7, and increase the energy density of the battery cell 7.

[0085] The embodiment of the present application provides a battery 2, which includes the battery cell 7 in the above embodiment. The embodiment of the present application also provides an electrical device, which includes the battery 2 in the above embodiment, and the battery 2 is used to provide electrical energy. The battery 2 and the electrical device in the embodiment of the present application both include the battery cell 7 in the above embodiment. In the battery cell 7, a current collecting assembly 6 is provided in the outer shell 40 to connect with the electrode assembly 10, and the electrode assembly 10 is electrically connected with other components to realize the transmission of electrical energy. The anti-oxidation layer 8 is provided at the connection between the current collecting assembly 6 and the outer shell 40, which can reduce the risk of rusting at the connection between the current collecting assembly 6 and the outer shell 40 due to contact with moisture and oxygen in the air, thereby causing cracks and leakage, thereby improving the overall structural strength of the outer shell 40 and improving the reliability of the operation of the battery cell 7.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell (7), comprising: A housing (40) having a receiving cavity; An electrode assembly (10) is disposed in the accommodating cavity; A current collecting assembly (6), the current collecting assembly (6) being connected to the electrode assembly (10), and the current collecting assembly (6) being connected to a side of the housing (40) facing the accommodating cavity; An anti-oxidation layer (8) is provided on a side of the housing (40) facing away from the accommodating cavity, and an orthographic projection of the anti-oxidation layer (8) on the housing (40) at least partially overlaps with an orthographic projection of the current collecting assembly (6) on the housing (40).

2. The battery cell (7) according to claim 1, wherein: The current collecting assembly (6) comprises: A current collecting plate (601), the edge of the current collecting plate (601) being connected to a side of the housing (40) facing the accommodating cavity, and a side surface of the current collecting plate (601) being connected to a pole ear of the electrode assembly (10); A first welding portion (602) is provided between the current collecting plate (601) and the housing (40) and is used to connect the current collecting plate (601) and the housing (40). The anti-oxidation layer (8) comprises a first protective layer (801), and the orthographic projection of the first protective layer (801) on the outer shell (40) completely covers the orthographic projection of the first welding portion (602) on the outer shell (40).

3. The battery cell (7) according to claim 2, wherein: The housing (40) comprises: A housing (20) having an opening; an end cover (30) covering the opening, and the end cover (30) and the housing (20) together enclose the accommodating cavity; The second welding portion (603) is provided between the housing (20) and the end cover (30). Wherein, the anti-oxidation layer (8) comprises a second protective layer (802), wherein the second protective layer (802) The orthographic projection on the outer shell (40) completely covers the orthographic projection of the second welding portion (603) on the outer shell (40).

4. The battery cell (7) according to claim 3, wherein: The first protective layer (801) and the second protective layer (802) are an integrally formed structure.

5. The battery cell (7) according to claim 3, wherein: The battery cell (7) further comprises an anti-corrosion layer disposed on a side of the housing (40) away from the accommodating cavity, the anti-corrosion layer having a notch at a position corresponding to the first welding portion (602) or the second welding portion (603), and the anti-oxidation layer (8) covers at least a portion of the notch.

6. The battery cell (7) according to claim 5, wherein: The anti-corrosion layer comprises a nickel layer, and the shell (40) is a steel shell (40) or a carbon steel shell (40).

7. The battery cell (7) according to any one of claims 1 to 6, wherein: The anti-oxidation layer (8) comprises at least one of a polyacrylate layer, a polyurethane layer and an epoxy resin layer.

8. The battery cell (7) according to any one of claims 1 to 6, wherein: An insulating layer (22) is also provided on the side of the outer shell (40) facing away from the accommodating cavity, and a surface of the outer shell (40) facing the insulating layer (22) is concave to form an accommodating groove (23), and at least a portion of the anti-oxidation layer (8) is provided in the accommodating groove (23).

9. A battery (2), wherein: The invention comprises a battery cell (7) as claimed in any one of claims 1 to 8.

10. An electrical device, comprising the battery (2) according to claim 9, wherein the battery (2) is used to provide electrical energy.

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