Battery cell, battery device, and electric device

Abstract

The application provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a shell and an electrode assembly. The shell is enclosed to form a containing cavity. The shell comprises a first side wall and a second side wall connected by bending. The first side wall has a first surface facing away from the containing cavity. The second side wall has a second surface facing away from the containing cavity. The area of the first surface is larger than that of the second surface. The electrode assembly is contained in the shell. The first side wall further comprises a third surface facing the containing cavity. The water contact angle of the first surface is larger than that of the third surface. In the embodiment of the application, the outer surface of the first side wall is subjected to hydrophobic treatment, so that the first surface has a larger water contact angle, thereby having stronger hydrophobic performance. In this way, the condensed water is not easy to infiltrate on the first surface, and can form water droplets to quickly roll off.

Description

Technical Field

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

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

[0003] In the development of battery technology, improving the reliability of individual battery cells has become a research direction. Utility Model Content

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

[0005] On one hand, embodiments of this application provide a battery cell, which includes a housing and an electrode assembly. The housing encloses a receiving cavity and includes a first sidewall and a second sidewall that are bent and connected. The first sidewall has a first surface facing away from the receiving cavity, and the second sidewall has a second surface facing away from the receiving cavity. The area of ​​the first surface is larger than the area of ​​the second surface. The electrode assembly is housed within the housing. The first sidewall also includes a third surface facing the receiving cavity, and the water contact angle of the first surface is larger than the water contact angle of the third surface.

[0006] In the above solution, by hydrophobically treating the outer surface of the first sidewall, a larger water contact angle is achieved, resulting in stronger hydrophobic properties. This prevents condensate from easily wetting the first surface and allows it to form droplets that quickly roll off. Considering the large area of ​​the first surface, this design helps reduce the accumulation of condensate on the casing, thereby lowering the risk of corrosion and insulation failure on the first sidewall and improving the reliability of the battery cell.

[0007] Furthermore, in this embodiment, only the outer surface of the shell is hydrophobically treated, while the inner surface of the shell is not hydrophobically treated. This results in the water contact angle of the first surface being greater than that of the third surface. This design allows the shell to be hydrophobically treated after the shell is prepared, rather than performing an overall hydrophobic operation on the board before the shell is formed. This helps to simplify the hydrophobic treatment process and improve the preparation efficiency.

[0008] In some embodiments, the water contact angle of the first surface is a1, where a1 ≥ 150°.

[0009] In the above solution, by hydrophobically treating the outer surface of the first sidewall, the water contact angle α1 of the first surface can be no less than 150°. In this way, condensate will not wet the first surface and can form water droplets and roll off quickly, thereby reducing the degree of condensate accumulation on the outer shell surface, improving the risk of corrosion and insulation failure of the outer shell, and improving the reliability of the battery cell.

[0010] In some embodiments, the first sidewall includes a body portion and a hydrophobic coating located on the side of the body portion away from the electrode assembly, the hydrophobic coating including a first surface. The body portion includes a fourth surface facing the hydrophobic coating, the water contact angle of the first surface being greater than the water contact angle of the fourth surface.

[0011] In the above solution, a hydrophobic coating is formed on the body by means of spraying or other methods, so that the first sidewall can include a first surface with a large water contact angle, thereby reducing the degree of condensation accumulation on the first sidewall, improving the risk of corrosion and insulation failure of the first sidewall, and improving the reliability of the battery cell.

[0012] In some embodiments, the hydrophobic coating is made of a perfluoroalkyl compound, a fluorosilicone compound, trimethylchlorosilane, or methyltriethoxysilane; and / or, the body is made of aluminum or aluminum oxide.

[0013] In the above scheme, both perfluoroalkyl compounds and fluorosilicone compounds are fluorides, and trimethylchlorosilane and methyltriethoxysilane are silane compounds. Both fluorides and silanes have low surface energy and can act as hydrophobic agents. Based on this, by spraying a low-surface-energy hydrophobic agent onto the body, a hydrophobic coating can be formed, creating a first surface with a large water contact angle. This reduces the accumulation of condensate on the first sidewall, mitigates the risk of corrosion and insulation failure on the first sidewall, and improves the reliability of the battery cell.

[0014] Both aluminum and aluminum oxide have strong hydrophilicity, and when there is a large temperature difference between the outer casing and the surrounding environment, condensation easily forms on the outer surface of the casing due to heat exchange. Based on this, this embodiment adds a hydrophobic coating to separate the main body from the external environment. Thus, when condensation occurs, it resides on the hydrophobic surface of the coating, rather than on the main body, thereby accelerating the rate at which condensation leaves the casing, reducing the risk of corrosion and insulation failure, and improving the reliability of the battery cell.

[0015] In some embodiments, the roughness of the fourth surface is greater than that of the third surface.

[0016] In the above scheme, by processing the body, a secondary microstructure is formed on the fourth surface, making the roughness of the fourth surface greater than that of the third surface, thereby improving the hydrophobic performance. Specifically, the formation of the hydrophobic surface corresponding to the first surface requires first constructing a micro-nano composite rough structure (such as micron-level protrusions, nano-level trenches, etc.) on the fourth surface to form an "air cushion" effect, thereby significantly reducing the actual contact area between condensate and the first surface. This design can meet the requirement of a larger water contact angle on the first surface, reduce the risk of condensate accumulation on the first surface, and improve the reliability of the battery cell.

[0017] In some embodiments, the water roll-off angle of the first surface is b, where b satisfies: b≤10°.

[0018] In the above solution, by hydrophobically treating the first surface, the water roll-off angle b of the first surface can be no greater than 10°, thereby helping the condensate on the first surface to roll off quickly, reducing the risk of condensate accumulating on the first surface and corroding the casing, and improving the reliability of the battery cell.

[0019] In some embodiments, the water contact angle of the second surface is greater than that of the third surface.

[0020] In the above scheme, in addition to hydrophobic treatment of the first sidewall, hydrophobic treatment is also performed on the second sidewall so that the water contact angle of the first surface and the second surface is greater than that of the third surface. This helps to reduce the accumulation of condensate on both the first and second surfaces, thereby further improving the risk of corrosion and insulation failure of the casing and improving the reliability of the battery cell.

[0021] In some embodiments, the battery cell further includes electrode terminals, which are electrically connected to the electrode assembly. The housing also includes a wall portion, a first sidewall, and a second sidewall that intersect at an angle. The electrode terminals are disposed on the wall portion, which includes a fifth surface facing away from the electrode assembly. The water contact angle of the fifth surface is greater than that of the third surface.

[0022] In the above solution, considering that the electrode terminals are disposed on the wall, the fifth surface of the wall is hydrophobically treated so that the water contact angle of the fifth surface is greater than that of the third surface, thereby reducing the risk of condensation accumulating on the fifth surface, improving the adverse effects of condensation on the electrode terminals, and improving the reliability of the battery cell.

[0023] Secondly, embodiments of this application provide a battery device, which includes a single battery cell in any of the foregoing embodiments.

[0024] In some embodiments, the battery device further includes a heat dissipation assembly surrounding the battery cell, the heat dissipation assembly including a first heat dissipation portion covering a first surface, the first heat dissipation portion being recessed on one side facing the first surface to form an air supply channel.

[0025] In the above solution, the heat dissipation component can meet the air cooling heat dissipation of the battery cell. However, air cooling heat dissipation is prone to causing condensation to form on the battery cell. In view of this, the embodiment of this application performs hydrophobic treatment on the first surface, so that the first surface has a larger water contact angle. As a result, the first surface can have stronger hydrophobic properties, so that condensation will not wet and corrode the first sidewall on the first surface, thereby reducing the probability of insulation failure of the casing and improving the reliability of the battery cell.

[0026] Thirdly, embodiments of this application provide an electrical device, which includes the battery device in any of the foregoing embodiments.

[0027] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of a vehicle provided in some embodiments of this application;

[0030] Figure 2 This is a schematic diagram of the structure of a battery device provided in some embodiments of this application;

[0031] Figure 3 This is a schematic diagram of the structure of a battery module in a battery device provided in some embodiments of this application;

[0032] Figure 4 This is a schematic diagram of the exploded structure of a single battery cell provided in some embodiments of this application;

[0033] Figure 5 This is a partial structural diagram of the outer casing of a battery cell provided in some embodiments of this application;

[0034] Figure 6This is a cross-sectional structural diagram of the first sidewall in a battery cell provided by some embodiments of this application;

[0035] Figure 7 This application provides a partially enlarged schematic diagram of the body portion of a battery cell according to some embodiments;

[0036] Figure 8 This application provides a schematic diagram illustrating the positional relationship between a battery cell and a heat dissipation component in a battery device, based on some embodiments of the present application.

[0037] Tag name:

[0038] 1000, Vehicle; 100, Battery unit; 200, Controller; 300, Motor; 400, Housing; 401, First housing section; 402, Second housing section; 403, Receiving section; 500, Battery cell; 600, Battery module;

[0039] 10. Outer shell; 11. First sidewall; 111. First surface; 112. Third surface; 113. Body portion; 114. Hydrophobic coating; 115. Fourth surface; 12. Second sidewall; 121. Second surface; 13. Wall portion; 131. Fifth surface; 14. Shell; 15. End cap;

[0040] 20. Electrode assembly;

[0041] 30. Electrode terminals;

[0042] 40. Heat dissipation assembly; 41. First heat dissipation section; 42. Second heat dissipation section; 43. Air supply channel;

[0043] X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0044] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0046] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0047] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0048] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0049] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0050] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0051] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0052] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0053] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0054] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0055] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0056] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0057] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator, with the separator positioned between the positive and negative electrodes. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0058] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0059] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0060] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0061] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium manganese iron phosphate, and lithium manganese iron phosphate and carbon composites. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (such as LiCoO2), lithium nickel oxides (such as LiNiO2), lithium manganese oxides (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, lithium nickel cobalt manganese oxides (such as LiNi1 / 3Co1 / 3Mn1 / 3O2 (also abbreviated as NCM333), LiNi0.5Co0.2Mn0.3O2 (also abbreviated as NCM523), LiNi0.5Co The following are included: 0.25Mn0.25O2 (also known as NCM211), LiNi0.6Co0.2Mn0.2O2 (also known as NCM622), LiNi0.8Co0.1Mn0.1O2 (also known as NCM811), lithium nickel cobalt aluminum oxides (such as LiNi0.8Co0.15Al0.05O2), and their modified compounds. Modified compounds refer to substances obtained by doping or coating, etc., based on the above-mentioned materials.

[0062] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, a positive electrode active material is filled and / or deposited within the foamed metal.

[0063] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0064] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, titanium, or silver. The composite current collector may include a polymer material substrate and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0065] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0066] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0067] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0068] In some embodiments, the negative electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When foamed metal is used as the negative electrode sheet, the surface of the foamed metal may or may not have a negative electrode active material.

[0069] As an example, negative electrode active materials can be filled or / and deposited within the negative electrode current collector.

[0070] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0071] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not impose specific limitations on the type of electrolyte; it can be selected according to requirements. The electrolyte may include electrolyte salts and solvents.

[0072] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0073] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0074] In some embodiments, the electrolyte may optionally include additives. For example, additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain properties of the battery cell, such as additives that improve the overcharge / fast charge performance of the battery cell, additives that improve the high-temperature performance of the battery cell, and additives that improve the low-temperature performance of the battery cell.

[0075] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0076] In some embodiments, the electrode assembly is a wound structure. The positive electrode and the negative electrode are wound into a wound structure.

[0077] In some implementations, the electrode assembly is a stacked structure.

[0078] As an example, multiple positive and negative electrode plates can be set, and multiple positive and multiple negative electrode plates can be stacked alternately.

[0079] As an example, multiple positive electrode sheets can be set, and negative electrode sheets are folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0080] As an example, both the positive and negative electrode sheets are folded to form multiple stacked folded segments.

[0081] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0082] As an example, the separator can be continuously arranged between any adjacent positive or negative electrode plates by folding or rolling.

[0083] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0084] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0085] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), a membrane, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0086] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0087] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0088] In some embodiments, at least one electrode terminal is provided on the housing, and the electrode terminal is electrically connected to the tab. The electrode terminal can be directly connected to the tab, or it can be indirectly connected to the tab through a current collector. The electrode terminal can be provided on the end cap or on the housing.

[0089] In some embodiments, the battery cell further includes a lower plastic layer disposed on the side of the end cap facing inwards from the housing. The lower plastic layer can be pre-formed as a single piece of plastic or assembled from various plastic components. The material of the lower plastic layer may include insulating material to provide insulation performance and improve electrical insulation between the internal components and the end cap. Furthermore, the lower plastic layer can also abut against the electrode assembly to fix and protect the electrode assembly, reducing the risk of open circuits due to displacement of the electrode assembly and other components during battery cell transportation and use, especially in vibrating environments.

[0090] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.

[0091] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.

[0092] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0093] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.

[0094] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0095] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0096] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first enclosure may be a top cover or a bottom plate.

[0097] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0098] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0099] In some embodiments, the battery device may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0100] In some battery cells, an insulating film is wrapped around the outer casing, while in others, this film is not present. For cells without an insulating film, in certain applications, the battery cell is in direct contact with air. This can easily lead to condensation on the air-exposed areas of the casing. Alternatively, when the battery cell is used in a battery pack, condensation from the pack may flow onto the casing, causing insulation failure, corrosion, and leakage, thus compromising the reliability of the battery cell.

[0101] Therefore, embodiments of this application provide a battery cell, a battery device, and an electrical device. By hydrophobically treating the outer surface of the first sidewall, the first surface has a larger water contact angle, thereby exhibiting stronger hydrophobic properties. This prevents condensate from easily wetting the first surface and allows water droplets to quickly roll off. Considering the large area of ​​the first surface, this design helps to reduce the accumulation of condensate on the outer casing, thereby reducing the risk of corrosion and insulation failure of the first sidewall and improving the reliability of the battery cell.

[0102] The technical solutions described in this application are applicable to battery cells, battery devices, and electrical devices using battery devices. Electrical devices can take many forms, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0103] The battery devices described in this application are not limited to the electrical devices described above, but for the sake of brevity, the following embodiments are all illustrated using electric vehicles as an example.

[0104] Please see Figure 1 , Figure 1This is a simplified schematic diagram of a vehicle 1000 provided in an embodiment of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 can be installed inside the vehicle 1000; specifically, for example, the battery device 100 can be installed at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 100 may also include a controller 200 and a motor 300. The controller 200, for example, is used to control the battery to supply power to the motor 300. The battery device 100 can be used for starting, navigation, etc., of the vehicle 1000. Of course, the battery device 100 can also be used to drive the vehicle 1000, replacing or partially replacing gasoline or natural gas to provide propulsion for the vehicle 1000.

[0105] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device provided in some embodiments of this application. The battery device 100 includes a housing 400 and individual battery cells (not shown), with the individual battery cells housed within the housing 400. The housing 400 is used to house the individual battery cells, and the housing 400 can have various structures. In some embodiments, the housing 400 may include a first housing portion 401 and a second housing portion 402, which overlap each other, and the first housing portion 401 and the second housing portion 402 together define a receiving portion 403 for housing the individual battery cells. The second box portion 402 can be a hollow structure with one end open, and the first box portion 401 is a plate-like structure. The first box portion 401 covers the open side of the second box portion 402 to form a box with a receiving portion 403. Alternatively, both the first box portion 401 and the second box portion 402 can be hollow structures with one side open, and the open side of the first box portion 401 covers the open side of the second box portion 402 to form a box 400 with a receiving portion. Of course, the first box portion 401 and the second box portion 402 can be various shapes, such as cylinders, cuboids, etc.

[0106] In the battery device 100, there can be one or more battery cells. If there are multiple battery cells, they can be connected in series, in parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells are connected in both series and parallel configurations. Multiple battery cells can be directly connected in series, in parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells is housed within the housing 400. Alternatively, multiple battery cells can first be connected in series, in parallel, or in a mixed configuration to form a battery module 600, and then the multiple battery modules 600 can be connected in series, in parallel, or in a mixed configuration to form a whole, which is then housed within the housing 400.

[0107] Figure 3 for Figure 2The diagram shows an exploded view of the battery module 600. In some embodiments, such as... Figure 3 As shown, there are multiple battery cells 500. These multiple battery cells 500 are first connected in series, parallel, or in a mixed manner to form a battery module 600. The multiple battery modules 600 are then connected in series, parallel, or in a mixed manner to form a whole, which is housed in the casing.

[0108] The structure of the battery cell 500 will now be described with reference to the accompanying drawings. Figure 4 and Figure 5 The battery cell 500 includes a housing 10 and an electrode assembly 20. The housing 10 encloses a receiving cavity and includes a first sidewall 11 and a second sidewall 12 that are bent and connected. The first sidewall 11 has a first surface 111 facing away from the receiving cavity, and the second sidewall 12 has a second surface 121 facing away from the receiving cavity. The area of ​​the first surface 111 is larger than the area of ​​the second surface 121. The electrode assembly 20 is received within the housing 10. The first sidewall 11 also includes a third surface 112 facing the receiving cavity, and the water contact angle of the first surface 111 is larger than the water contact angle of the third surface 112.

[0109] The outer casing 10 is a component used to form the internal environment of the battery cell 500. This internal environment can accommodate the electrode assembly 20, the electrolyte, and other components. The electrode assembly 20 is the component in the battery cell 500 where electrochemical reactions occur. The electrode assembly 20 is mainly formed by winding or stacking positive and negative electrode sheets, and typically a separator is provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly 20, while the portions without active material each constitute a tab. The positive and negative tabs can be located together at one end of the main body or separately at both ends. During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs connect to the electrode terminals 30 to form a current loop.

[0110] The outer casing 10 can have various shapes. Optionally, the outer casing 10 can be square, meaning the battery cell 500 is a square-shell battery cell. Alternatively, the outer casing 10 can also be cylindrical, meaning the battery cell 500 is a cylindrical battery cell.

[0111] The first sidewall 11 and the second sidewall 12 are wall structures of the outer casing 10 at different peripheral positions. Specifically, the first sidewall 11 is located on one side of the electrode assembly 20 along the first direction X, and the second sidewall 12 is located on one side of the electrode assembly 20 along the second direction Y. The first direction X, the second direction Y, and the axial direction of the electrode assembly 20 intersect each other. Optionally, the outer casing 10 may also include a bottom wall, which is located on one side of the electrode assembly 20 along the axial direction. The first sidewall 11, the second sidewall 12, and the bottom wall are arranged at an angle. Further optionally, the first direction X, the second direction Y, and the axial direction are perpendicular to each other.

[0112] The first surface 111 is the surface on the first sidewall 11 that faces away from the electrode assembly 20, and the second surface 121 is the surface on the second sidewall 12 that faces away from the electrode assembly 20. The area of ​​the first surface 111 is larger than the area of ​​the second surface 121; that is, the first surface 111 is a large surface, and the second surface 121 is a narrow surface. Here, a large surface refers to the surface with a larger area in the circumferential direction of the outer shell 10, while a narrow surface refers to the surface with a smaller area in the circumferential direction of the outer shell 10. Optionally, the dimension of the first surface 111 in the second direction Y is larger than the dimension of the second surface 121 in the first direction X.

[0113] The third surface 112 is the surface on the first sidewall 11 facing the electrode assembly 20, and the third surface 112 is used to enclose and form a receiving cavity together with other surfaces. The third surface 112 may have the same area as the first surface 111, or the area of ​​the third surface 112 may be slightly smaller than the area of ​​the first surface 111.

[0114] In the actual application of the battery cell 500, if condensation is generated or dripped on the casing 10, the condensation is more likely to accumulate on the first surface 111 because the first surface 111 has a larger area. That is, more condensation is more likely to accumulate on the first sidewall 11, which makes the casing 10 more prone to insulation failure at the first sidewall 11, affecting the reliability of the battery cell 500.

[0115] Therefore, in this embodiment, the outer surface of the first sidewall 11 is hydrophobically treated, resulting in a larger water contact angle for the first surface 111. Specifically, the water contact angle, also known as the water wetting angle, refers to the angle between the solid-liquid interface, the liquid interior, and the gas-liquid interface at the solid-liquid-gas three-phase interface. It reflects the degree of wetting of the solid by the liquid and is a quantitative measure of surface wettability. For example, a drop of condensate will spread out on a clean glass surface, while a drop of condensate will remain as a droplet on a waxy surface, indicating non-wetting. Wetting and non-wetting are not polar opposites but a quantifiable quantity; the parameter that quantifies the degree of wetting is the water contact angle.

[0116] Typically, the water contact angle can be measured using a goniometer, such as a static contact angle meter, by dropping water droplets onto the first surface 111 and the third surface 112 and measuring them separately. Generally, the larger the water contact angle, the greater the degree of contraction of the liquid on the solid surface, and the stronger the hydrophobicity of the surface. Conversely, the smaller the water contact angle, the greater the degree of spread of the liquid on the solid surface, and the stronger the hydrophilicity of the surface.

[0117] Therefore, in this embodiment, by hydrophobically treating the outer surface of the first sidewall 11, the first surface 111 has a larger water contact angle, thereby exhibiting stronger hydrophobic properties. This prevents condensate from easily wetting the first surface 111 and allows water droplets to quickly roll off. Considering the large area of ​​the first surface 111, this design helps to reduce the accumulation of condensate on the outer casing 10, thereby reducing the risk of corrosion and insulation failure of the first sidewall 11 and improving the reliability of the battery cell 500.

[0118] Furthermore, in this embodiment, only the outer surface of the outer shell 10 is hydrophobically treated, while the inner surface of the outer shell 10 is not hydrophobically treated. This results in the water contact angle of the first surface 111 being greater than that of the third surface 112. This design allows the outer shell 10 to be hydrophobically treated after its fabrication is complete, rather than performing an overall hydrophobic operation on the substrate before the outer shell 10 is formed. This helps to simplify the hydrophobic treatment process and improve the fabrication efficiency.

[0119] It should be noted that, depending on the actual needs, only the outer surface of the first sidewall 11 may be hydrophobically treated, without hydrophobically treating the second sidewall 12. In this case, the water contact angle of the first surface 111 is greater than the water contact angle of the second surface 121. Alternatively, in some other embodiments, both the outer surfaces of the first sidewall 11 and the second sidewall 12 may be hydrophobically treated. In this case, the water contact angle of the first surface 111 may be greater than, less than, or equal to the water contact angle of the second surface 121.

[0120] Furthermore, the battery cell 500 can be manufactured in various ways. For example, the casing 10 can be hydrophobically treated first, and then the electrode assembly 20 can be assembled into the casing 10. Alternatively, the electrode assembly 20 can be assembled into the casing 10 first, and then the casing 10 can be hydrophobically treated. Optionally, in the manufacturing process of the battery cell 500, the casing 10 can be hydrophobically treated first, and then the electrode assembly 20 can be assembled into the casing 10. This helps to reduce the adverse effects of the hydrophobic treatment process on the structure and performance of the electrode assembly 20.

[0121] In some embodiments, the water contact angle of the first surface 111 is a1, where a1 ≥ 150°. Exemplarily, a1 is one of 150°, 160°, 170°, 80°, and 200°.

[0122] In this embodiment of the application, by hydrophobically treating the outer surface of the first sidewall 11, the water contact angle α1 of the first surface 111 is not less than 150°. In this way, condensate will not wet the first surface 111 and can form water droplets and roll off quickly, thereby reducing the degree of condensate accumulation on the surface of the outer casing 10, improving the risk of corrosion and insulation failure of the outer casing 10, and improving the reliability of the battery cell 500.

[0123] In some embodiments, please refer to Figure 6 The first sidewall 11 includes a body portion 113 and a hydrophobic coating 114 located on the side of the body portion 113 facing away from the electrode assembly 20. The hydrophobic coating 114 includes a first surface 111. The body portion 113 includes a fourth surface 115 facing the hydrophobic coating 114, and the water contact angle of the first surface 111 is greater than the water contact angle of the fourth surface 115.

[0124] The body portion 113 is the main part of the first sidewall 11 that protects the electrode assembly 20, and the third surface 112 is located on the body portion 113. The hydrophobic coating 114 is a coating structure with strong hydrophobic properties, disposed on the surface of the body portion 113 away from the electrode assembly 20. The fourth surface 115 is located on the side of the body portion 113 away from the electrode assembly 20, and the hydrophobic coating 114 is in contact with the fourth surface 115. The hydrophobic coating 114 can be formed in various ways; optionally, the hydrophobic coating 114 can be formed by spraying.

[0125] In this embodiment, by forming a hydrophobic coating 114 on the body 113 by means of spraying or the like, the first sidewall 11 can include a first surface 111 with a large water contact angle, thereby reducing the degree of condensation accumulation on the first sidewall 11, improving the risk of corrosion and insulation failure of the first sidewall 11, and improving the reliability of the battery cell 500.

[0126] In some embodiments, the hydrophobic coating 114 is made of a perfluoroalkyl compound, a fluorosilicone compound, trimethylchlorosilane, or methyltriethoxysilane.

[0127] In this embodiment, both the perfluoroalkyl compound and the fluorosilicone compound are fluorides, and both trimethylchlorosilane and methyltriethoxysilane are silane compounds. Both fluorides and silane compounds have low surface energy and can act as hydrophobic agents. Based on this, by spraying a low-surface-energy hydrophobic agent onto the body portion 113, a hydrophobic coating 114 can be formed, creating a first surface 111 with a large water contact angle. This reduces the accumulation of condensate on the first sidewall 11, mitigates the risk of corrosion and insulation failure on the first sidewall 11, and improves the reliability of the battery cell 500.

[0128] In some embodiments, the material of the body portion 113 includes aluminum or aluminum oxide.

[0129] In this embodiment, both aluminum and aluminum oxide have strong hydrophilicity. When there is a large temperature difference between the outer casing 10 and the surrounding environment, condensation easily forms on the outer surface of the outer casing 10 due to heat exchange between the outer casing 10 and the external environment. Based on this, this embodiment adds a hydrophobic coating 114 to separate the main body 113 from the external environment. Thus, when condensation occurs, it resides on the hydrophobic surface of the hydrophobic coating 114, rather than on the main body 113. This accelerates the rate at which condensation leaves the outer casing 10, reduces the risk of corrosion and insulation failure of the outer casing 10, and improves the reliability of the battery cell 500.

[0130] In some embodiments, please refer to Figure 6 and Figure 7 The roughness of the fourth surface 115 is greater than that of the third surface 112.

[0131] In this embodiment, by processing the body 113, a secondary microstructure is formed on the fourth surface 115, making the roughness of the fourth surface 115 greater than that of the third surface 112, thereby improving the hydrophobic performance. Specifically, the formation of the hydrophobic surface corresponding to the first surface 111 requires first constructing a micro-nano composite rough structure (such as micron-level protrusions, nano-level trenches, etc.) on the fourth surface 115 to form an "air cushion" effect, thereby significantly reducing the actual contact area between condensate and the first surface 111. This design can meet the requirement of a larger water contact angle of the first surface 111, reduce the risk of condensate accumulation on the first surface 111, and improve the reliability of the battery cell 500.

[0132] Next, this application embodiment will describe the operation process of hydrophobic treatment. Optionally, the fourth surface 115 of the body 113 is first cleaned alternately with alcohol and deionized water to ensure that the fourth surface 115 is free of dust and dirt. Then, a filler, such as a silicone structure, is inserted into the shell 10. The filler and the third surface 112 are fitted with a gap to reduce damage to the shell. Then, sandpaper wheels with a mesh size between 1000 and 5000 are used to alternately roll the fourth surface 115 in different directions under a certain pressure to form a micron-scale sieve structure. Then, argon gas or the like is used to perform plasma treatment on the fourth surface 115, thereby etching nano-scale microstructures on the micron-scale sieve surface to form a sieve-like micro-nano composite rough structure, giving the fourth surface 115 a large roughness. After that, a low surface energy hydrophobic agent is sprayed onto the fourth surface 115 through chemical modification to form a hydrophobic coating 114. Finally, the filler is removed, and the battery cell 500 is placed in a dry environment at 40℃ or 60℃ for 4 hours to complete the hydrophobic treatment.

[0133] In some embodiments, the water roll-off angle of the first surface 111 is b, where b ≤ 10°. Exemplarily, b is one of 2°, 4°, 5°, 8°, and 10°.

[0134] The water roll-off angle refers to the critical tilt angle at which a droplet begins to roll on an inclined solid surface, and is used to evaluate the surface's wettability and hydrophobicity. It reflects contact hysteresis; a smaller water roll-off angle indicates stronger surface hydrophobicity. Therefore, this embodiment of the application hydrophobizes the first surface 111, ensuring that the water roll-off angle b of the first surface 111 is no greater than 10°. This helps condensate on the first surface 111 to roll off quickly, reducing the risk of condensate accumulation on the first surface 111 and corroding the casing 10, thereby improving the reliability of the battery cell 500.

[0135] In some embodiments, the water contact angle of the second surface 121 is greater than the water contact angle of the third surface 112.

[0136] Regarding the outer surface of the outer casing 10, the first surface 111 is a large surface, and the second surface 121 is a narrow surface. The water contact angles of both the first surface 111 and the second surface 121 are greater than the water contact angle of the third surface 112, indicating that both the first sidewall 11 and the second sidewall 12 have undergone hydrophobic treatment. The water contact angle of the second surface 121 can be greater than, less than, or equal to the water contact angle of the first surface 111.

[0137] In some alternative embodiments, the water contact angle of the second surface 121 is a2, where a2 ≥ 150°. Exemplarily, a2 is one of 150°, 160°, 170°, 80°, and 200°.

[0138] In this embodiment, in addition to hydrophobic treatment of the first sidewall 11, the second sidewall 12 is also hydrophobic treated so that the water contact angles of the first surface 111 and the second surface 121 are both greater than the water contact angle of the third surface 112. This helps to reduce the accumulation of condensate on both the first surface 111 and the second surface 121, thereby further improving the risk of corrosion and insulation failure of the casing 10 and improving the reliability of the battery cell 500.

[0139] In some embodiments, such as Figure 4 and Figure 5 As shown, the battery cell 500 also includes an electrode terminal 30, which is electrically connected to the electrode assembly 20. The housing 10 also includes a wall portion 13, which, along with a first side wall 11 and a second side wall 12, intersects at an angle. The electrode terminal 30 is disposed on the wall portion 13. The wall portion 13 includes a fifth surface 131 that faces away from the electrode assembly 20. The water contact angle of the fifth surface 131 is greater than that of the third surface 112.

[0140] The electrode terminal 30 is a key component in the battery cell 500 used for connecting external devices, and it can be used to conduct electrical signals or current. Depending on the actual needs, the electrode terminal 30 can be directly connected to the electrode assembly 20, or the electrode terminal 30 can also be electrically connected to the electrode assembly 20 through a current collector.

[0141] The wall portion 13 is a wall structure of the housing 10. The electrode terminal 30 is disposed on the wall portion 13. The wall portion 13 is located on one side of the electrode assembly 20 along the third direction Z and intersects the first side wall 11 and the second side wall 12 at an angle. The housing 10 may include a housing 14 and an end cap 15, with the end cap 15 covering the housing 14. Optionally, the wall portion 13 can be the end cap 15, or the wall portion 13 can be a wall structure within the housing 14.

[0142] The fifth surface 131 is the surface of the wall 13 facing away from the electrode assembly 20. Similar to the first surface 111, the fifth surface 131 is also hydrophobically treated, such that the water contact angle of the fifth surface 131 is greater than that of the third surface 112. Optionally, the water contact angle of the fifth surface 131 is a3, where a3 ≥ 150°. Exemplarily, a3 is one of 150°, 160°, 170°, 80°, and 200°.

[0143] Considering that the electrode terminal 30 is disposed on the wall portion 13, the fifth surface 131 of the wall portion 13 in this embodiment of the application is hydrophobically treated so that the water contact angle of the fifth surface 131 is greater than that of the third surface 112, thereby reducing the risk of condensate accumulating on the fifth surface 131, improving the adverse effects of condensate on the electrode terminal 30, and improving the reliability of the battery cell 500.

[0144] Secondly, embodiments of this application provide a battery device 100, which includes a battery cell 500 in any of the foregoing embodiments.

[0145] It should be noted that the battery device 100 provided in this application embodiment has the beneficial effects of the battery cell 500 in any of the aforementioned embodiments. For details, please refer to the aforementioned description of the beneficial effects of the battery cell 500. This application embodiment will not repeat the description.

[0146] In some embodiments, please refer to Figure 8 The battery device 100 also includes a heat dissipation assembly 40 surrounding the battery cell 500. The heat dissipation assembly 40 includes a first heat dissipation part 41 covering the first surface 111. The first heat dissipation part 41 is recessed on the side facing the first surface 111 to form an air supply channel 43.

[0147] The heat dissipation component 40 is arranged around the battery cell 500. On the one hand, the heat dissipation component 40 can provide insulation protection for the battery cell 500, and on the other hand, it can help the battery cell 500 dissipate heat. Specifically, the first heat dissipation part 41 is the part of the heat dissipation component 40 that covers the first surface 111. The first heat dissipation part 41 is not a flat structure and is closely attached to the battery cell 500. The side of the first heat dissipation part 41 facing the second surface 121 is recessed to form an air supply channel 43. The air supply channel 43 is connected to the external environment at both ends in the third direction Z. Ambient air can pass through the air supply channel 43 in the third direction Z and carry away some of the heat on the battery cell 500, thereby realizing the air cooling function of the battery cell 500.

[0148] The air supply channel 43 can have various sizes and shapes. Optionally, the first heat dissipation part 41 includes multiple reinforcing rib structures, with adjacent reinforcing rib structures spaced apart to form the air supply channel 43. The setting of the reinforcing rib structure can not only meet the formation requirements of the air supply channel 43, but also improve the structural strength of the heat dissipation component 40 and enhance the protection effect of the heat dissipation component 40 on the battery cell 500.

[0149] It should be noted that the heat dissipation assembly 40 also includes a second heat dissipation part 42 covering the first side, and the second heat dissipation part 42 can take various forms. Optionally, the second heat dissipation part 42 does not have a recess to form an air supply channel 43, and the second heat dissipation part 42 includes two independent parts, thereby facilitating the installation and removal of the heat dissipation assembly 40 and the battery cell 500.

[0150] The heat dissipation component 40 can meet the air cooling requirements of the battery cell 500. However, air cooling can easily lead to condensation on the battery cell 500. Therefore, this embodiment of the application performs hydrophobic treatment on the first surface 111, so that the first surface 111 has a larger water contact angle. As a result, the first surface 111 has stronger hydrophobic properties, so that condensation will not wet and corrode the first sidewall 11 on the first surface 111, thereby reducing the probability of insulation failure of the casing 10 and improving the reliability of the battery cell 500.

[0151] Thirdly, embodiments of this application provide an electrical device, which includes the battery device 100 in any of the foregoing embodiments.

[0152] According to some embodiments of this application, please refer to Figures 4 to 7 The battery cell 500 includes a housing 10, an electrode assembly 20, and an electrode terminal 30. The housing 10 encloses and forms a receiving cavity. The housing 10 includes a wall portion 13, a first side wall 11, and a second side wall 12. The wall portion 13, the first side wall 11, and the second side wall 12 intersect at an angle. The electrode terminal 30 is disposed on the wall portion 13. The first side wall 11 has a first surface 111 facing away from the receiving cavity, and the second side wall 12 has a second surface 121 facing away from the receiving cavity. The area of ​​the first surface 111 is larger than the area of ​​the second surface 121. The electrode assembly 20 is received within the housing 10.

[0153] The wall portion 13 includes a third surface 112 facing the receiving cavity, and the water contact angles of the first surface 111 and the second surface 121 are both greater than the water contact angle of the third surface 112. The water contact angle of the first surface 111 is a1, where a1 ≥ 150°. The first sidewall 11 encloses the body portion 113 and a hydrophobic coating 114 located on the side of the body portion 113 facing away from the electrode assembly 20. The hydrophobic coating 114 includes the first surface 111, and the body portion 113 includes a fourth surface 115 facing the hydrophobic coating 114. The water contact angle of the first surface 111 is greater than the water contact angle of the fourth surface 115, and the roughness of the fourth surface 115 is greater than the roughness of the third surface 112.

[0154] The wall portion 13 includes a fifth surface 131 facing away from the electrode assembly 20, the water contact angle of the fifth surface 131 being greater than the water contact angle of the third surface 112.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: The outer shell encloses and forms a receiving cavity. The outer shell includes a first sidewall and a second sidewall that are bent and connected. The first sidewall has a first surface that is opposite to the receiving cavity, and the second sidewall has a second surface that is opposite to the receiving cavity. The area of ​​the first surface is larger than the area of ​​the second surface. Electrode assembly, housed within the housing; The first sidewall also includes a third surface facing the receiving cavity, wherein the water contact angle of the first surface is greater than the water contact angle of the third surface.

2. The battery cell according to claim 1, characterized in that, The water contact angle of the first surface is a1, where a1 ≥ 150°.

3. The battery cell according to claim 1, characterized in that, The first sidewall includes a body portion and a hydrophobic coating located on the side of the body portion opposite to the electrode assembly, the hydrophobic coating including the first surface; The body portion includes a fourth surface facing the hydrophobic coating, wherein the water contact angle of the first surface is greater than the water contact angle of the fourth surface.

4. The battery cell according to claim 3, characterized in that, The hydrophobic coating material is a perfluoroalkyl compound, a fluorosilicone compound, trimethylchlorosilane, or methyltriethoxysilane; and / or, The material of the body includes aluminum or aluminum oxide.

5. The battery cell according to claim 3, characterized in that, The roughness of the fourth surface is greater than that of the third surface.

6. The battery cell according to claim 1, characterized in that, The water roll-off angle of the first surface is b, and b satisfies: b≤10°.

7. The battery cell according to claim 1, characterized in that, The water contact angle of the second surface is greater than that of the third surface.

8. The battery cell according to claim 1, characterized in that, The battery cell also includes electrode terminals, which are electrically connected to the electrode assembly. The housing also includes a wall portion, the wall portion, the first sidewall, and the second sidewall intersect at an angle, the electrode terminal is disposed on the wall portion, and the wall portion includes a fifth surface facing away from the electrode assembly, the water contact angle of the fifth surface being greater than the water contact angle of the third surface.

9. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1-8.

10. The battery device according to claim 9, characterized in that, It also includes a heat dissipation assembly surrounding the battery cell, the heat dissipation assembly including a first heat dissipation part covering the first surface, the first heat dissipation part being recessed on one side facing the first surface to form an air supply channel.

11. An electrical appliance, characterized in that, Includes the battery device as described in claim 9 or 10.

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