Battery cell, battery and electric device

Abstract

The utility model 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

Technical Field

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

[0002] Battery cells are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, electric tools, and energy storage systems, etc. Battery cells can include nickel-cadmium battery cells, nickel-hydrogen battery cells, lithium-ion battery cells, sodium-ion battery cells, and secondary alkaline zinc-manganese battery cells, etc.

[0003] 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. Utility Model Content

[0004] 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.

[0005] In a first aspect, the present application provides a battery cell, comprising a housing, an electrode assembly, a current collecting assembly, and an anti-oxidation layer. The housing has a receiving cavity. The electrode assembly is disposed in the receiving cavity. The current collecting assembly is connected to the electrode assembly, and the current collecting assembly 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, and the orthographic projection of the anti-oxidation layer on the housing at least partially overlaps with the orthographic projection of the current collecting assembly on the housing.

[0006] In the technical solution of the embodiment of the present application, a current collecting assembly is provided in the housing to connect with the electrode assembly, and the electrode assembly is electrically connected to an external device to realize the transmission of electric energy. The anti-oxidation layer is provided at the connection between the current collecting assembly and the housing, which can reduce the risk of rusting at the connection between the current collecting assembly and the housing due to contact with moisture and oxygen in the air, thereby causing cracks and leakage, improve the overall structural strength of the housing, and improve the reliability of the operation of the battery cell.

[0007] In some embodiments, the current collecting assembly includes a current collecting plate and a first welding portion, the edge of the current collecting plate is connected to the side of the shell facing the accommodating cavity, and the surface of one side of the current collecting plate is connected to the pole ear of the electrode assembly. The first welding portion is arranged between the current collecting plate and the shell, and is used to connect the current collecting plate and the shell. Among them, 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 plate is provided for welding with the electrode assembly to improve the connection strength between the electrode assembly and the current collecting assembly, and the first welding portion connects the current collecting plate 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, which reduces the probability of the shell rusting when it contacts the moisture and oxygen in the air at the position of the first welding portion, reduces the risk of cracks and leakage in the shell, improves the overall structural strength of the shell, and improves the reliability of the operation of the battery cell.

[0008] In some embodiments, the housing includes a housing, an end cap, and a second weld. The housing has an opening. The end cap covers the opening, and the end cap and the housing together enclose a receiving cavity. The second weld is disposed between the housing and the end cap. The anti-oxidation layer includes a second protective layer, and the orthographic projection of the second protective layer on the housing completely covers the orthographic projection of the second weld on the housing.

[0009] In the above structure, the second weld connects the end cap to the shell, improving the connection strength between the end cap and the shell. The second protective layer covers the position where the second weld connects to the shell, reducing the probability of the shell corroding when it contacts moisture and oxygen in the air at the position of the second weld, 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.

[0010] In some embodiments, the first protective layer and the second protective layer are an integrated structure. In the above technical solution, the integrated structure improves the efficiency of anti-oxidation layer manufacturing and enhances the overall structural strength of the housing.

[0011] In some embodiments, the battery cell further includes an anti-corrosion layer disposed on a side of the shell away from the accommodating cavity, the anti-corrosion layer has a notch at a position corresponding to the first welding portion or the second welding portion, and the anti-oxidation layer covers at least part of the notch.

[0012] In the above structure, the anti-corrosion layer can improve the overall structural strength and anti-corrosion performance of the outer shell. Providing an anti-oxidation layer at the location where an opening defect appears in the anti-corrosion layer can reduce the probability of the outer 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 outer shell, improving the overall structural strength of the outer shell, and improving the reliability of the operation of the battery cell.

[0013] In some embodiments, the anti-corrosion layer includes a nickel layer, and the shell is a steel shell or a carbon steel shell. In the above structure, the shell is made of nickel-plated steel or nickel-plated carbon steel, which can improve the overall structural strength of the shell and have good electrical conductivity; the nickel plating layer is dense and has low porosity, which can improve the strength, hardness and corrosion resistance of steel or carbon steel.

[0014] In some embodiments, the anti-oxidation layer includes at least one of a polyacrylate layer, a polyurethane layer, and an epoxy resin layer. In the above structure, the connection strength with the shell is high, the anti-corrosion performance is strong, and it is suitable for various spraying processes, thereby improving the manufacturing efficiency.

[0015] In some embodiments, an insulating layer is further provided on the side of the shell facing away from the accommodating cavity, and the surface of the shell facing the insulating layer is concave to form an accommodating groove, and at least part of the anti-oxidation layer is provided in the accommodating groove. In the above structure, by providing the insulating layer, the insulation performance of the shell is improved, and the safety of the battery cell operation process is improved; and the accommodating groove is provided on the surface of the shell to accommodate the anti-oxidation layer, which can reduce the thickness of the anti-oxidation layer protruding from the surface of the shell, reduce the space occupied by the anti-oxidation layer, improve the surface flatness of the battery cell, and improve the energy density of the battery cell.

[0016] In a second aspect, the present application provides a battery, which includes the battery cell in the above embodiment.

[0017] 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.

[0018] 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

[0019] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0020] Figure 1 A schematic diagram of the structure of a vehicle according to an embodiment of the present application;

[0021] Figure 2 This is a schematic diagram of the exploded structure of a battery according to an embodiment of the present application;

[0022] Figure 3 A schematic diagram of the structure of a battery cell according to an embodiment of the present application;

[0023] Figure 4 A schematic diagram of the structure of a battery cell according to another embodiment of the present application;

[0024] Figure 5 for Figure 4 A schematic diagram of the enlarged structure of the middle circle A;

[0025] Figure 6 This is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0026] Figure 7 for Figure 6 A schematic diagram of the enlarged structure of the middle circle B;

[0027] Figure 8 This is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0028] Fig. 9 for Figure 8 A schematic diagram of the enlarged structure of the middle circle C;

[0029] Fig.10 This is a schematic structural diagram of a battery cell according to another embodiment of the present application;

[0030] Fig.11 for Fig.10 Schematic diagram of the enlarged structure of the middle circle D.

[0031] DETAILED DESCRIPTION OF REFERENCE NUMERALS

[0032] 1. Vehicle; 2. Battery; 10. Electrode assembly; 20. Shell; 22. Insulating layer; 23. Receiving groove; 24. Upper current collector; 25. Electrode terminal; 26. Lower current collector; 30. End cover; 40. Shell; 3. Controller; 4. Motor; 5. Box; 51. First part; 52. Second part; 53. Receiving 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

[0033] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field 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" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0035] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0036] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0037] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0038] 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).

[0039] 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. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which 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 referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0040] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0041] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, 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., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0042] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0043] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application. Vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may 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 may be provided at the bottom, the head or the tail of the vehicle 1. The battery 2 may be used to power the vehicle 1, for example, the battery 2 may be used as an operating power source for the vehicle 1. The vehicle 1 may also include a controller 3 and a motor 4, and the controller 3 is used to control the battery 2 to power the motor 4, for example, for the starting, navigation and working power requirements of the vehicle 1 during driving.

[0044] In some embodiments of the present application, the battery 2 can be used 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.

[0045] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0046] Please refer to Figure 2 , Figure 2 The exploded diagram of the battery provided in some embodiments of the present application. The battery 2 includes a box body 5 and a battery cell 7, and the battery cell 7 is accommodated in the box body 5. The box body 5 is used to provide a storage space for the battery cell 7, and the box body 5 can adopt a variety of structures.

[0047] In some optional embodiments, the box body 5 includes a first part 51 and a second part 52, the first part 51 and the second part 52 cover each other, and the first part 51 and the second part 52 jointly define a storage space 53 for accommodating the battery cell 7. The second part 52 can be a hollow structure with one end open, and the first part 51 can be a plate-like structure, and the first part 51 covers the open side of the second part 52, so that the first part 51 and the second part 52 jointly define the storage space 53; the first part 51 and the second part 52 can also be hollow structures with one side open, and the open side of the first part 51 covers the open side of the second part 52. Of course, the box body 5 formed by the first part 51 and the second part 52 can be a variety of shapes, such as a cylinder, a cuboid, etc.

[0048] In some embodiments, the box 5 can be used as part of the chassis structure of the vehicle 1. For example, part of the box 5 can become at least a part of the floor of the vehicle 1, or part of the box 5 can become at least a part of the cross beam and longitudinal beam of the vehicle 1.

[0049] In the battery 2, there can be multiple battery cells 7, and the multiple battery cells 7 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 7 are both connected in series and in parallel. The multiple battery cells 7 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 7 is accommodated in the box 5. Of course, the battery 2 can also be a battery module formed by connecting multiple battery cells 7 in series, in parallel, or in mixed connection, and then the multiple battery modules are connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 5. The battery 2 can also include other structures, for example, the battery 2 can also include a converging component for realizing the electrical connection between the multiple battery cells 7.

[0050] Each battery cell 7 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 7 may be cylindrical, flat, rectangular or in other shapes.

[0051] Please refer to Figure 3 , Figure 3 The schematic diagram of the structure of the battery cell 7 provided in some embodiments of the present application. The battery cell 7 refers to the smallest unit constituting the battery 2. Figure 3 The battery cell 7 includes a housing 40, an electrode assembly 10 and other functional components.

[0052] 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 may be adapted to the shape of the shell 20 to match the shell 20. Optionally, the end cap 30 may be made of a material with a certain hardness and strength (such as an 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 may be provided on the end cap 30. The electrode terminal 25 can be used to be electrically connected to the electrode assembly 10 for outputting or inputting electrical energy of the battery cell 7.

[0053] In some embodiments, the end cap 30 may also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 7 reaches a threshold value. The material of the end cap 30 may also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this. In some embodiments, an insulating component may also be provided on the inner side of the end cap 30, and the insulating component may be used to isolate the electrical connection components in the housing 20 from the end cap 30 to reduce the risk of short circuit. Exemplarily, the insulating component may be plastic, rubber, etc.

[0054] The shell 20 is a component used to cooperate with the end cap 30 to form the internal environment of the battery cell 7. Among them, the formed internal environment can be used to accommodate the electrode assembly 10, the electrolyte and other components. The shell 20 and the end cap 30 can be independent components, and an opening can be set on the shell 20, and the internal environment of the battery cell 7 is formed by covering the opening with the end cap 30 at the opening. Without limitation, the end cap 30 and the shell 20 can also be integrated. Specifically, the end cap 30 and the shell 20 can form a common connection surface before other components are put into the shell, and when the interior of the shell 20 needs to be encapsulated, the end cap 30 is covered with the shell 20. The shell 20 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 20 can be determined according to the specific shape and size of the electrode assembly 10. The material of the shell 20 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0055] The electrode assembly 10 is a component in the battery cell 7 where electrochemical reactions occur. One or more electrode assemblies 10 may be included in 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 and removed back and forth between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can prevent the positive and negative electrodes from short-circuiting, and at the same time allow active ions to pass through.

[0056] In some embodiments, the separator is a separator. The present application has no particular restrictions on the type of separator, and any known porous separator with good chemical stability and mechanical stability can be selected. As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic.

[0057] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0058] In some embodiments, the battery cell 7 further includes an electrolyte, which plays a role in conducting ions between the positive and negative electrodes. The present application has no specific restrictions on the type of electrolyte, which can be selected according to needs. The electrolyte can be liquid, gel or solid.

[0059] In some embodiments, the electrode assembly 10 is a wound structure. Optionally, the electrode assembly 10 is a laminated structure.

[0060] In some embodiments, the shape of the electrode assembly 10 can be cylindrical, flat, or polygonal.

[0061] 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.

[0062] In some embodiments, the battery cell 7 includes a current collecting assembly, which is used to connect the electrode assembly 10 and the shell 20. The current collecting assembly includes an upper current collecting member 24 and a lower current collecting member 26. One side of the upper current collecting member 24 is connected to a pole ear of the electrode assembly 10, and the other side is welded to the electrode terminal 25. One side of the lower current collecting member 26 is connected to the other pole ear of the electrode assembly 10, and the circumference of the lower current collecting member 26 is connected to the inner wall of the shell 20.

[0063] With the development of battery technology, the structural stability of the battery cell shell has attracted attention. Since the battery cell generates heat during operation, the metal shell is in contact with the air under high temperature conditions and is easily oxidized by the oxygen and moisture in the air, causing oxidation and rust of the shell. Therefore, when the shell leaves the factory, an anti-corrosion coating is usually applied to its surface. The anti-corrosion coating is applied as a whole using a spraying or electroplating process.

[0064] The lower current collector in the battery is usually connected to the outer shell by welding. For example, the position where the lower current collector is connected to the outer shell can be heated so that part of the lower current collector melts and connects to the shell. After cooling, a firm connection is formed between the lower current collector and the outer shell. However, the heating process will damage the anti-oxidation coating on the outside of the outer shell. As a result, a gap is formed in the anti-oxidation coating at the position where the lower current collector is connected to the outer shell, and the metal outer shell is exposed to the outside and undergoes an oxidation reaction with oxygen and moisture in the air, causing oxidation and rust of the outer shell. In the rusted part, the outer shell will crack and leak, reducing the safety of the battery cell during operation and shortening its service life.

[0065] Based on the above considerations, the present application provides a battery cell, including a housing, an electrode assembly, a current collecting assembly, and an anti-oxidation layer. The housing has a receiving cavity. The electrode assembly is disposed in the receiving cavity. The current collecting assembly is connected to the electrode assembly, and the current collecting assembly 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, and the orthographic projection of the anti-oxidation layer on the housing at least partially overlaps with the orthographic projection of the current collecting assembly on the housing.

[0066] In the technical solution of the embodiment of the present application, a current collecting assembly is provided in the housing to connect with the electrode assembly, and the electrode assembly is electrically connected with other components to realize the transmission of electric energy. The anti-oxidation layer is provided at the connection between the current collecting assembly and the housing, which can reduce the risk of rusting at the connection between the current collecting assembly and the housing due to contact with moisture and oxygen in the air, thereby causing cracks and leakage, improve the overall structural strength of the housing, and improve the reliability of the operation of the battery cell.

[0067] like Figure 4 as well as Figure 5 As shown, in some embodiments of the present application, the current collecting assembly 6 includes a current collecting disc 601 and a first welding portion 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 pole ear of the electrode assembly 10. The first welding portion 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. Among them, the anti-oxidation layer 8 includes a first protective layer 801, and the orthographic projection of the first protective layer 801 on the housing 40 completely covers the orthographic projection of the first welding portion 602 on the housing 40.

[0068] Exemplarily, the first welding part 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 part 602 may be formed by melting the solder at high temperature and cooling it. The shape of the current collecting plate 601 may match the shape of the end cover 30, and the edge of the current collecting plate 601 abuts or fits against the inner wall of the shell 40. The orthographic projection of the first protective layer 801 on the shell 40 completely covers the orthographic projection of the first welding part 602 on the shell 40, and the orthographic projection of the first protective layer 801 on the shell 40 may completely overlap with the orthographic projection of the first welding part 602 on the shell 40, or the orthographic projection area of ​​the first protective layer 801 on the shell 40 may be larger than the orthographic projection of the first welding part 602 on the shell 40.

[0069] In the above structure, the current collecting plate 601 is provided for welding with the electrode assembly 10, thereby improving the connection strength between the electrode assembly 10 and the current collecting assembly 6, and the first welding portion 602 connects the current collecting plate 601 with the housing 40, thereby improving the connection strength between the current collecting assembly 6 and the housing 40. The first protective layer 801 covers the position where the first welding portion 602 is connected with the housing 40, thereby reducing the probability of the housing 40 being corroded by contact with moisture and oxygen in the air at the position of the first welding portion 602, thereby reducing the risk of cracks and leakage in the housing 40, thereby improving the overall structural strength of the housing 40, and improving the reliability of the operation of the battery cell 7.

[0070] like Figure 6 as well as Figure 7 As shown, in some optional embodiments, the first welding portion 602 can penetrate the shell 40 and extend to the side of the shell 40 away from the accommodating cavity. In the above structure, the first welding portion 602 penetrates the shell 40, which can improve the strength of the connection between the collecting plate 601 and the shell 40.

[0071] like Figure 8 as well as Fig. 9 As shown, in some embodiments of the present application, the housing 40 includes a housing 20, an end cap 30, and a second fusion portion 603. The housing 20 has an opening. The end cap 30 covers the opening, and the end cap 30 and the housing 20 together enclose a receiving cavity. The second fusion portion 603 is disposed between the housing 20 and the end cap 30. Among them, the anti-oxidation layer 8 includes a second protective layer 802, and the orthographic projection of the second protective layer 802 on the housing 40 completely covers the orthographic projection of the second fusion portion 603 on the housing 40.

[0072] In the above structure, the second weld 603 connects the end cap 30 to the shell 20, thereby improving the connection strength between the end cap 30 and the shell 20. The second protective layer 802 covers the position where the second weld 603 is connected to the shell 40, thereby reducing the probability of the shell 40 being corroded by contact with moisture and oxygen in the air at the position of the second weld 603, 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.

[0073] 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.

[0074] In some embodiments of the present application, the battery cell 7 also includes an anti-corrosion layer arranged on the side of the shell 40 away from the accommodating cavity, the anti-corrosion layer has a notch corresponding to the position of the first welding part 602 or the second welding part 603, and the anti-oxidation layer 8 covers at least part of the notch.

[0075] 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 with the collecting plate 601 and the end cover 30. The anti-corrosion layer at the above position will be damaged by high temperature to form a gap. Therefore, an anti-oxidation layer 8 can be set at the above position. Optionally, during the manufacturing process of the shell 20, scratches and collisions may occur, causing the anti-corrosion layer to be damaged and form a gap, and an anti-oxidation layer 8 can also be set at the above 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 position can reduce the probability of rusting of the metal shell 20 at the gap and improve the overall structural strength of the shell 20.

[0076] In the above structure, the anti-corrosion layer can improve the overall structural strength and anti-corrosion performance of the outer shell 40. An anti-oxidation layer 8 is provided at the position where defects occur in the anti-corrosion layer, which can reduce the probability of rusting caused by contact between the outer shell 40 exposed at the position of the gap in the anti-corrosion layer and moisture and oxygen in the air, thereby reducing the risk of cracks and leakage in the outer shell 40, improving the overall structural strength of the outer shell 40, and improving the reliability of the operation of the battery cell 7.

[0077] Exemplarily, 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 and completely surrounds the notch. Exemplarily, the minimum distance between the edge of the anti-oxidation layer 8 and the edge of the notch is 0.1 mm.

[0078] 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. The above thickness range can reduce the overall thickness and mass of the housing 20 as much as possible while improving the anti-corrosion effect.

[0079] 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.

[0080] In some embodiments of the present application, the anti-oxidation layer 8 includes 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. The above thickness range can reduce the overall thickness and quality of the housing 20 while ensuring the anti-oxidation performance of the welding portion of the housing 20.

[0081] In the above structure, the anti-oxidation layer 8 is made of organic material with a viscosity in the range of 1 to 1000 cps, which has high connection strength with the metal shell 40 and strong corrosion resistance, and is suitable for various spraying processes and has high manufacturing efficiency.

[0082] like Fig.10 as well as Fig.11 As shown, in some embodiments of the present application, an insulating layer 22 is further provided on the side of the housing 40 away from the accommodating cavity, and the surface of the housing 40 facing the insulating layer 22 is concave to form an accommodating groove 23, and at least part of the anti-oxidation layer 8 is provided in the accommodating groove 23. In the above structure, by providing the insulating layer 22, the insulation performance of the housing 40 is improved, and the safety of the battery cell 7 during operation is improved. In addition, the accommodating groove 23 is provided on the surface of the housing 40 to accommodate the anti-oxidation layer 8, which 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 improve the energy density of the battery cell 7.

[0083] 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, improve the overall structural strength of the outer shell 40, and improve the reliability of the operation of the battery cell 7.

[0084] 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 replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should 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), characterized in that: include: 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, characterized in that: 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, characterized in that: 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). The anti-oxidation layer (8) comprises a second protective layer (802), and the orthographic projection of the second protective layer (802) 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, characterized in that: 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, characterized in that: 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, characterized in that: 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, characterized in that: 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, characterized in that: 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), characterized in that: The invention comprises a battery cell (7) as claimed in any one of claims 1 to 8.

10. An electrical device, characterized in that: The electrical device comprises the battery (2) as claimed in claim 9, and the battery (2) is used to provide electrical energy.

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