Battery, preparation method thereof and power utilization device

Abstract

The invention discloses a battery, a preparation method thereof and a power utilization device, and can provide a super-hydrophobic anti-icing battery box body, so that the operation of replacing the battery in a low-temperature environment is facilitated, and the operation simplicity and replacement efficiency of replacing the battery in the power utilization device are improved. The battery includes: a battery cell; the box body is used for accommodating the battery monomers; wherein the box body comprises a plurality of walls, the box body is defined by the walls, at least one of the walls comprises a base material and a coating arranged on at least one side surface of the base material, the water contact angle theta of the coating is larger than or equal to 150 degrees, and the water rolling angle alpha of the coating is smaller than or equal to 10 degrees.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a battery and its preparation method and an electrical device. Background Technology

[0002] With increasing environmental pollution, the new energy industry is attracting more and more attention. Within the new energy industry, battery technology is a crucial factor in its development.

[0003] The battery installation methods of existing electrical devices are generally divided into fixed and replaceable types. Replaceable batteries are widely used because of their advantages such as easy replacement and high flexibility. As a result, the ease of replacement and the efficiency of replacement have become the focus of attention. Summary of the Invention

[0004] This application is made in view of the above-mentioned problems, and its purpose is to provide a battery housing with superhydrophobic and anti-icing properties, which facilitates the operation of replacing batteries in electrical devices in low-temperature environments and improves the ease of operation and efficiency of battery replacement.

[0005] To achieve the above objectives, this application provides a battery, a method for preparing the same, and an electrical device thereof.

[0006] In a first aspect, a battery is provided, comprising: a battery cell; a housing for accommodating the battery cell; wherein the housing includes a plurality of walls that enclose the housing, at least one of the plurality of walls including a substrate and a coating disposed on at least one surface of the substrate, wherein the water contact angle θ of the coating satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°.

[0007] In this embodiment, the water contact angle θ of the coating on the battery casing wall satisfies: θ ≥ 150°, and the water roll-off angle α of the coating satisfies: α ≤ 10°. Since both the water contact angle and water roll-off angle are within the aforementioned ranges, the coating exhibits excellent hydrophobicity, reducing the likelihood of liquid water adhering to the battery casing wall, thereby reducing the risk of the coating surface freezing at low temperatures due to adhering liquid water. Thus, when the battery is installed in the electrical device, the battery and the device's chassis will not be connected due to ice formation on the battery casing wall. When replacing the battery, it is not necessary to first remove the ice between the battery and the device's chassis to separate them before replacing the battery. This facilitates battery replacement in low-temperature environments, improving the ease and efficiency of battery replacement.

[0008] In one possible implementation, the impact strength K of the coating satisfies: 100 kJ / m 2≤K≤200kJ / m 2 .

[0009] In this embodiment, the impact strength of the coating on the wall of the battery box is within the above-mentioned range. The coating has good impact resistance, reducing the risk of the coating being damaged under external impact and reducing the risk of the substrate of the box wall being exposed and corroded.

[0010] In one possible implementation, the coating comprises polyamide and hydrophobic silica, wherein the polyamide has a volume average particle size Dv50. 1 Satisfies: 30μm≤Dv50 1 ≤100μm; the volume average particle size Dv50 of the hydrophobic silica. 2 Satisfies: 100nm≤Dv50 2 ≤200nm.

[0011] In this embodiment, the coating on the battery case wall uses polyamide with a specific particle size range, which improves the surface roughness of the coating, giving it good mechanical properties, enhancing its impact resistance, and reducing the risk of damage under external impact. The wall coating also uses hydrophobic silica with a specific particle size range to improve its hydrophobicity and reduce the risk of icing at low temperatures. This technical solution, through the combined use of polyamide and hydrophobic silica with specific particle size ranges, constructs a micro-nano structure for the coating on the case wall, giving the coating both good mechanical and hydrophobic properties. This improves the battery case wall's anti-icing properties in low-temperature environments, facilitating battery replacement in low-temperature conditions.

[0012] In one possible implementation, the weight percentage P1 of the hydrophobic silica, based on the total weight of the coating, satisfies: 8% ≤ P1 ≤ 24%.

[0013] By setting the weight percentage of hydrophobic silica in the coating within the above range, it is beneficial to improve the hydrophobicity of the coating, thereby improving the coating's anti-icing performance at low temperatures.

[0014] In one possible implementation, the polyamide includes at least one of polycaprolactam, polydodecanolactam, and polyhexamethylene adipamide.

[0015] In one possible implementation, the hydrophobic silica comprises fluorine-modified silica.

[0016] Fluorine-modified silica has good hydrophobic and anti-icing properties, as well as good corrosion resistance. The coating of the box wall includes fluorine-modified silica, which helps to improve the hydrophobicity and anti-icing properties of the coating.

[0017] In one possible implementation, based on the total weight of the fluorine-modified silica, the weight percentage of fluorine, P2, satisfies: 0.8% ≤ P2 ≤ 8%.

[0018] By setting the weight percentage of fluorine in fluorinated silica within the above-mentioned range, it is beneficial to provide fluorinated silica with good hydrophobicity, anti-icing properties and corrosion resistance, which is beneficial to improving the hydrophobicity, anti-icing properties and corrosion resistance of the coating.

[0019] In one possible implementation, the coating further includes an adhesive, which includes polytetrafluoroethylene resin and polyurethane.

[0020] The coating incorporates both low surface energy polytetrafluoroethylene resin and polyurethane with good adhesion. By combining the two polymers, the coating's adhesion and mechanical strength are improved while ensuring its hydrophobic properties.

[0021] In one possible implementation, the polytetrafluoroethylene resin comprises acrylate-modified polytetrafluoroethylene.

[0022] Acrylic-modified polytetrafluoroethylene has a certain degree of hydrophobicity, which can improve the adhesion of the coating and reduce the risk of liquid adhesion, thus improving the hydrophobicity of the coating.

[0023] In one possible implementation, the coating further includes an interface modifier comprising an amino-containing silane coupling agent.

[0024] In amino-containing silane coupling agents, the amino functional groups have high reactivity and can react with specific groups in the polymer or form hydrogen bonds, thereby enhancing the adhesion between polymers. Adding amino-containing silane coupling agents to the coating can improve the compatibility between polyurethane, polyamide and hydrophobic silica, improve the adhesion between polyurethane and the substrate, and thus improve the adhesion and mechanical strength of the coating.

[0025] In one possible implementation, the amino-containing silane coupling agent includes at least one of aminopropyltriethoxysilane, aminobutyltriethoxysilane, aminopropyltrimethoxysilane, and aminobutyltrimethoxysilane.

[0026] In one possible implementation, the coating further includes a thickener, which includes at least one of polypropylene, polyethylene, and polyvinyl chloride.

[0027] Adding a thickener during the coating preparation process adjusts the viscosity of the coating slurry, which is beneficial for the mixing of various substances in the coating slurry and for the coating slurry to be applied.

[0028] In one possible implementation, the thickness L of the coating satisfies: 60μm≤L≤100μm.

[0029] When the coating thickness L≥60μm, the coating has good mechanical properties and good impact resistance, which can improve the structural strength of the housing; when the coating thickness L≤100μm, it is beneficial to reduce the space occupied by the battery, which can save the space reserved for the battery in the power device, thereby reducing the size of the power device.

[0030] In one possible implementation, the substrate comprises an aluminum alloy.

[0031] Aluminum alloys have a low density, which can reduce the weight of the battery case and provide lightweight batteries; at the same time, aluminum alloys have high strength, which can improve the impact resistance of the battery case, and aluminum alloys also have good corrosion resistance, which can extend the service life of the case.

[0032] In one possible implementation, the battery is disposed above the chassis of the power device, the housing includes a bottom wall disposed opposite to the chassis, the bottom wall including the substrate and the coating disposed on the surface of the substrate near the chassis.

[0033] In a second aspect, a method for manufacturing a battery is provided, comprising: providing a housing to manufacture the battery, wherein the housing is used to accommodate a single battery cell; wherein providing the housing comprises: providing a plurality of walls, at least one of the plurality of walls comprising a substrate and a coating disposed on at least one surface of the substrate, wherein the water contact angle θ of the coating satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°; and enclosing the plurality of walls to form the housing.

[0034] In the battery manufacturing method of this application embodiment, the water contact angle of the coating on the wall of the battery casing satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°. Therefore, the coating has good hydrophobicity, which allows the battery casing to have good hydrophobicity, reducing the possibility of liquid water adhering to the wall of the battery casing, thereby reducing the risk of the coating surface freezing at low temperatures due to adhering liquid water. When the manufactured battery is applied to an electrical device, it can improve the ease of operation and efficiency of battery replacement.

[0035] In one possible implementation, providing multiple walls includes: mixing polyamide and hydrophobic silica to obtain a slurry of the coating, wherein the polyamide has a volume average particle size Dv50. 1 Satisfies: 30μm≤Dv50 1 The volume average particle size Dv50 of the hydrophobic silica is ≤100μm. 2Satisfies: 100nm≤Dv50 2 ≤200nm; The slurry of the coating is applied to the surface of at least one side of the substrate to form the wall.

[0036] The above-mentioned battery preparation method is relatively simple and has low complexity. Furthermore, the prepared battery has good impact resistance, superhydrophobicity, and anti-icing properties. When applied to electrical devices, this battery facilitates battery replacement in low-temperature environments.

[0037] Thirdly, an electrical device is provided, comprising a battery as described in the first aspect and any possible implementation thereof, and / or a battery obtained by the preparation method of the second aspect.

[0038] In one possible implementation, the electrical device includes a heavy-duty truck.

[0039] Heavy-duty trucks operate in complex and challenging environments, making their battery housings more susceptible to impacts from gravel, which can damage the coating and cause the housing to lose its hydrophobic and anti-icing properties. Heavy-duty trucks have high requirements for the impact resistance of their battery housings, as well as their hydrophobicity and anti-icing properties in low-temperature environments. Applying batteries to electrical devices like heavy-duty trucks facilitates battery replacement in low-temperature environments, improving the ease and efficiency of battery replacement in heavy-duty trucks. Attached Figure Description

[0040] 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 the drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the structure of a battery according to an embodiment of this application;

[0042] Figure 2 This is a schematic diagram of the battery casing according to an embodiment of this application;

[0043] Figure 3 This is a schematic diagram of the wall structure of a box according to an embodiment of this application;

[0044] Figure 4 This is a schematic flowchart illustrating a method for preparing a battery according to an embodiment of this application;

[0045] Figure 5 This is a schematic diagram of a battery cell according to an embodiment of this application;

[0046] Figure 6This is a schematic diagram of a heavy-duty truck according to an embodiment of this application;

[0047] Figure 7 This is a Fourier transform infrared spectrum of a coating material according to an embodiment of this application. Detailed Implementation

[0048] The battery and its manufacturing method, as well as embodiments of the electrical device described in this application, have been explained in detail with reference to the accompanying drawings. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0049] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0050] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0051] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0052] Unless otherwise specified, all steps in 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.

[0053] In this application embodiment, the battery cell may include lithium-ion batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and this application embodiment is not limited to these. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and this application embodiment is not limited to these. Battery cells are generally divided into three types according to their packaging method: cylindrical battery cells, cuboid / square battery cells, and pouch battery cells, and this application embodiment is not limited to these.

[0054] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. A battery generally includes a housing for encapsulating one or more battery cells. The housing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0055] To meet diverse power demands, a battery can comprise multiple individual battery cells, which can be connected in series, parallel, or a combination of both. Optionally, multiple battery cells can first be connected in series, parallel, or a combination of both to form a battery module, and then these battery modules can be connected in series, parallel, or a combination of both to form a battery. In other words, multiple battery cells can directly form a battery, or they can first be assembled into battery modules, and then the battery modules can be assembled into a battery. The battery is then further installed in an electrical device to provide power to that device.

[0056] With increasing environmental pollution, the new energy industry is attracting more and more attention. Within the new energy industry, battery technology is a crucial factor in its development.

[0057] The battery installation methods of existing electrical devices are generally divided into fixed and replaceable types. Replaceable batteries are widely used because they have the advantages of being replaceable at any time and being highly flexible. As a result, the ease of replacement and the efficiency of replacement have become the focus of attention.

[0058] Especially in low-temperature environments, liquid water adhering to the outer surface of the battery pack can freeze. For example, in heavy-duty trucks, the battery is mounted on top of the vehicle's chassis without any other protective components such as underbody protection plates. The battery and chassis are directly opposite each other with a certain gap between them. In low-temperature environments, the liquid water adhering to the bottom wall of the battery can freeze and fill the gap between the battery and the chassis. It can even cause the bottom wall of the battery and the chassis of the vehicle to stick together with the ice, thereby increasing the complexity of battery replacement and making battery swapping difficult.

[0059] In view of this, this application provides a battery, including a battery cell; a housing for accommodating the battery cell; wherein the housing includes multiple walls, the multiple walls forming the housing, at least one of the multiple walls including a substrate and a coating disposed on at least one side surface of the substrate, the water contact angle θ of the coating satisfying: θ≥150°, and the water roll-off angle α of the coating satisfying: α≤10°. In the embodiments of this application, the water contact angle and water roll-off angle of the coating on the wall of the battery housing are respectively within the above-mentioned ranges, the coating has good hydrophobicity, which can reduce the possibility of liquid water adhering to the wall of the battery housing, thereby reducing the risk of the coating surface freezing at low temperatures due to the adhering liquid water. In this way, when the battery is installed in the electrical device, the battery and the chassis of the electrical device will not be connected due to the ice on the wall of the battery housing, and when the electrical device replaces the battery, it is not necessary to remove the ice between the battery and the chassis of the electrical device to separate them before the battery replacement operation, thereby facilitating the operation of replacing the battery in low-temperature environments and improving the ease and efficiency of battery replacement.

[0060] The following describes several embodiments of this application in detail.

[0061] [Battery]

[0062] This application provides a battery, including a battery cell and a housing, the housing being used to house the battery cell.

[0063] To meet different power demands, battery 10 may include multiple individual battery cells. For example, such as Figure 1 The diagram shown is a structural schematic of a battery 10 according to an embodiment of this application. The battery 10 may include multiple battery cells 3. The battery 10 may also include a housing 11, which has a hollow interior, and the multiple battery cells 3 are housed within the housing 11. For example, the multiple battery cells 3 may be connected in parallel, series, or a combination thereof and then placed inside the housing 11.

[0064] The enclosure 11 includes multiple walls, which enclose the enclosure 11 to form it. For example, as shown... Figure 1As shown, the housing 11 may include two parts, referred to herein as a first housing part 111 and a second housing part 112. The first housing part 111 and the second housing part 112 may each include multiple walls, and the first housing part 111 and the second housing part 112 are fastened together. The shapes of the first housing part 111 and the second housing part 112 can be determined according to the shape of the components housed inside, for example, according to the shape of a combination of multiple battery cells 3 housed inside. At least one of the first housing part 111 and the second housing part 112 has an opening. For example, as... Figure 1 As shown, the first housing portion 111 and the second housing portion 112 can both be hollow cuboids with one open side each. The openings of the first housing portion 111 and the second housing portion 112 are opposite to each other, and the first housing portion 111 and the second housing portion 112 are interlocked to form a housing 11 with a closed chamber, which can be used to accommodate multiple battery cells 3. The multiple battery cells 3 are connected in parallel, series, or mixed and placed inside the housing 11 formed by the interlocking of the first housing portion 111 and the second housing portion 112.

[0065] For example, unlike Figure 1 As shown, either the first housing portion 111 or the second housing portion 112 can have only one being a hollow cuboid with an opening, while the other is plate-shaped, or a wall, to cover the opening. Taking the second housing portion 112 as a hollow cuboid with an opening, and the first housing portion 111 as a plate-shaped example, then the first housing portion 111 covers the opening of the second housing portion 112 to form a housing 11 with a closed chamber, which can be used to accommodate multiple battery cells 3.

[0066] Among the multiple walls of the housing 11, at least one wall includes a substrate and a coating disposed on at least one side of the substrate.

[0067] For example, such as Figure 2 As shown, the box 11 is a cuboid, and the box 11 includes six walls 101. At least one wall 101 includes a substrate 1011 and a coating 1012 disposed on at least one side surface of the substrate 1011 (e.g., Figure 3 (As shown).

[0068] The substrate 1011 has two opposing surfaces along its thickness direction. The coating 1012 can be disposed on one surface of the substrate 1011 or on both surfaces of the substrate 1011. As an example, such as... Figure 3 As shown, coating 1012 is disposed on both sides of substrate 1011.

[0069] For example, the coating 1012 may be disposed on one side surface of the substrate 1011. When multiple walls 101 enclose a box 11 with a closed cavity, the coating 1012 is disposed on the side surface of the substrate 1011 away from the cavity of the box 11 in the thickness direction (not shown in the figure).

[0070] For example, the battery 10 can be applied to a heavy-duty truck. The battery 10 is disposed above the chassis of the heavy-duty truck. The wall of the housing 11 disposed opposite to the chassis of the heavy-duty truck is the bottom wall. In this case, the bottom wall of the housing 11 is configured to include a substrate 1011 and a coating 1012 disposed on the surface of the substrate 1011 near the chassis. That is, the coating 1012 of the bottom wall is disposed on the side that is in contact with the external environment, so that water, oil and dust in the external environment come into contact with the coating 1012 without directly contacting the substrate 1011 of the bottom wall, thereby reducing the risk of damage to the substrate 1011.

[0071] For example, the battery 10 can be applied to a heavy truck. The battery 10 is disposed in the gap between the front and the body of the heavy truck. In this case, the housing 11 has at least four walls exposed to the external environment. The structure of the multiple walls of the housing 11 exposed to the external environment includes a substrate 1011 and a coating 1012 disposed on the surface of the substrate 1011 on the side away from the chamber of the housing 11.

[0072] Specifically, the water contact angle θ of coating 1012 satisfies: θ≥150°, and the water roll-off angle α of coating 1012 satisfies: α≤10°.

[0073] The water contact angle is the angle formed at the point of contact between the gas, liquid, and solid phases when a water droplet lands on a solid surface. It is formed by two lines tangent to the surface profile of the water droplet and the solid surface (representing the solid-liquid interface and the liquid-gas interface, respectively). The water contact angle is less than 180°. Generally, a water contact angle < 90° is defined as hydrophilic, and a water contact angle ≥ 90° is defined as hydrophobic.

[0074] For example, θ can be 150°, 155°, 160°, 165°, 170°, 175°, or a value within the range obtained by any combination of the above two values.

[0075] The water roll-off angle is mainly used to characterize the wettability of a specific surface. It refers to the critical angle formed between the inclined surface and the horizontal plane when a water droplet just begins to roll on the inclined surface. The smaller the water roll-off angle, the easier it is for the water droplet to roll on the inclined surface, indicating better hydrophobicity of the surface.

[0076] For example, α can be 4°, 5°, 6°, 7°, 8°, 9°, 10°, or its value can be within the range obtained by any combination of the above two values.

[0077] In this embodiment, the water contact angle θ of the coating 1012 on the wall of the battery housing 11 satisfies: θ ≥ 150°, and the water roll-off angle α of the coating 1012 satisfies: α ≤ 10°. Since the water contact angle and water roll-off angle of the coating 1012 are within the above ranges, the coating 1012 exhibits excellent hydrophobicity, which reduces the possibility of liquid water adhering to the wall of the battery housing 11, thereby reducing the risk of the coating 1012 surface freezing at low temperatures due to adhering liquid water. Thus, when the battery is installed in the electrical device, the battery and the chassis of the electrical device will not be connected due to ice formation on the wall of the battery housing 11. When replacing the battery in the electrical device, it is not necessary to first remove the ice between the battery and the chassis of the electrical device to separate them before replacing the battery. This facilitates battery replacement in low-temperature environments, improving the ease and efficiency of battery replacement.

[0078] In some embodiments, the impact strength K of the coating 1012 satisfies: 100 kJ / m 2 ≤K≤200kJ / m 2 .

[0079] For example, K can be 100 kJ / m 2 120kJ / m 2 150kJ / m 2 160kJ / m 2 170kJ / m 2 180kJ / m 2 200kJ / m 2 , or its value is within the range obtained by combining any two of the above values.

[0080] In this embodiment of the application, the impact strength of the coating 1012 on the wall of the battery box 11 is within the above-mentioned range. The coating 1012 has good impact resistance, reducing the risk of the coating 1012 being damaged under external impact and reducing the risk of the substrate 1011 of the box wall being exposed and corroded.

[0081] In some embodiments, coating 1012 may comprise polyamide and hydrophobic silica, wherein the volume average particle size of the polyamide is Dv50. 1 Satisfies: 30μm≤Dv50 1 ≤100μm; Volume average particle size Dv50 of hydrophobic silica 2 Satisfies: 100nm≤Dv50 2 ≤200nm.

[0082] Hydrophobic silica can be silica that has undergone surface treatment to acquire hydrophobic properties (e.g., silica treated with silane). Exemplarily, surface-treated hydrophobic silica can be formed using a vapor phase method or a precipitation method.

[0083] For example, hydrophobic silica may include fluorine-modified silica.

[0084] For example, fluorosilanes can be used to surface-treat silica materials to obtain fluorinated silica.

[0085] Fluorine-modified silica has good hydrophobic and anti-icing properties, as well as good corrosion resistance. The coating 1012 on the wall of the housing 11 includes fluorine-modified silica, which helps to improve the hydrophobicity and anti-icing properties of the coating 1012.

[0086] For example, the volume average particle size Dv50 of polyamide 1 The value can be 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 95μm, 100μm, or a value within the range obtained by any combination of the above two values.

[0087] For example, the volume average particle size Dv50 of hydrophobic silica 2 It can be 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm, 200nm, or a value within the range obtained by any combination of the above two values.

[0088] In this embodiment, the coating 1012 of the battery housing 11 wall uses polyamide with a specific particle size range, which can improve the surface roughness of the coating 1012, giving it good mechanical properties, improving its impact resistance, and reducing the risk of damage under external impact. The wall coating 1012 also uses hydrophobic silica with a specific particle size range, enhancing its hydrophobicity and reducing the risk of icing at low temperatures. The technical solution of this application, through the combined use of polyamide and hydrophobic silica with specific particle size ranges, constructs a micro-nano structure for the coating 1012 of the housing 11 wall, giving it both good mechanical and hydrophobic properties, thereby improving the anti-icing properties of the battery housing 11 wall in low-temperature environments and facilitating battery replacement in low-temperature conditions.

[0089] In some embodiments, based on the total weight of coating 1012, the weight percentage P1 of hydrophobic silica satisfies: 8% ≤ P1 ≤ 24%.

[0090] For example, P1 can be 8%, 9%, 10%, 12%, 15%, 16%, 17%, 18%, 20%, 22%, 24%, or a value within the range obtained by any combination of the above two values.

[0091] By setting the weight percentage of hydrophobic silica in coating 1012 within the above range, it is beneficial to improve the hydrophobicity of coating 1012, thereby improving the anti-icing performance of coating 1012 at low temperatures.

[0092] In some embodiments, the polyamide includes at least one of polycaprolactam, polydodecanolactam, and polyhexamethylene adipamide.

[0093] In some embodiments, based on the total weight of fluorine-modified silica, the weight percentage of fluorine, P2, satisfies: 0.8% ≤ P2 ≤ 8%.

[0094] For example, P2 can be 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 4%, 4.5%, 5%, 6%, 7%, 7.5%, 8%, or a value within the range obtained by any combination of the above two values.

[0095] By setting the weight percentage of fluorine in the fluorinated silica within the above range, it is beneficial to provide fluorinated silica with good hydrophobicity, anti-icing properties and corrosion resistance, which is beneficial to improving the hydrophobicity, anti-icing properties and corrosion resistance of coating 1012.

[0096] In some embodiments, coating 1012 further includes an adhesive, which includes polytetrafluoroethylene resin and polyurethane.

[0097] The coating 1012 incorporates both low surface energy polytetrafluoroethylene resin and polyurethane with good adhesion. By combining the two polymers, the adhesion and mechanical strength of the coating 1012 are improved while ensuring its hydrophobic properties.

[0098] In some embodiments, the polytetrafluoroethylene resin includes acrylate-modified polytetrafluoroethylene.

[0099] Acrylic-modified polytetrafluoroethylene has a certain degree of hydrophobicity, which can improve the adhesion of coating 1012 while reducing the risk of liquid adhesion, thus improving the hydrophobicity of coating 1012.

[0100] In some embodiments, polyurethane can be formed by crosslinking the first component and the second component.

[0101] Specifically, in the preparation process of the slurry for coating 1012, the first component is added first, and then the second component is added. The first and second components are mixed and reacted in the slurry to form polyurethane.

[0102] For example, the first component may include at least one of polyether polyol and polyester polyol.

[0103] For example, the second component may include at least one of toluene diisocyanate (TDI), isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), and hexamethylene diisocyanate (HDI).

[0104] In some embodiments, coating 1012 further includes an interface modifier, which includes an amino-containing silane coupling agent.

[0105] In amino-containing silane coupling agents, the amino functional groups have high reactivity and can react with specific groups in the polymer or form hydrogen bonds, thereby enhancing the adhesion between polymers. Adding an amino-containing silane coupling agent to the coating 1012 can improve the compatibility between polyurethane, polyamide and hydrophobic silica, improve the adhesion between polyurethane and substrate 1011, thereby improving the adhesion and mechanical strength of the coating 1012.

[0106] In some embodiments, the amino-containing silane coupling agent includes at least one of aminopropyltriethoxysilane, aminobutyltriethoxysilane, aminopropyltrimethoxysilane, and aminobutyltrimethoxysilane.

[0107] In some embodiments, coating 1012 further includes a thickener, which includes polypropylene.

[0108] Adding a thickener during the preparation of coating 1012 adjusts the viscosity of the coating 1012 slurry, which is beneficial for the mixing of various substances in the coating 1012 slurry and for the coating of the coating 1012 slurry.

[0109] In some embodiments, such as Figure 3 As shown, the thickness of coating 1012 is L, and L satisfies: 60μm≤L≤100μm.

[0110] For example, the thickness L of the coating 1012 can be 60μm, 70μm, 75μm, 80μm, 90μm, 95μm, 100μm, or a value within the range obtained by any combination of the above two values.

[0111] When the thickness L of coating 1012 is ≥ 60 μm, coating 1012 has good mechanical properties and good impact resistance, which can improve the structural strength of the housing 11. When the thickness L of coating 1012 is ≤ 100 μm, it is beneficial to reduce the space occupied by the battery, which can save the space reserved for the battery in the power supply device, thereby reducing the volume of the power supply device.

[0112] In some embodiments, the substrate 1011 comprises an aluminum alloy. Exemplarily, the substrate 1011 may comprise an aluminum-magnesium alloy.

[0113] Aluminum alloy has a low density, which can reduce the weight of the casing 11 and provide a lightweight battery; at the same time, aluminum alloy has high strength, which can improve the impact resistance of the battery casing 11, and aluminum alloy also has good corrosion resistance, which can extend the service life of the casing 11.

[0114] The above text combined Figures 1 to 3 An embodiment of the battery is described below, in conjunction with... Figure 4 Examples of methods for preparing a battery are described below. Similar descriptions in the examples of methods for preparing a battery can be found in the descriptions of the examples of batteries, and will not be repeated below.

[0115] [Battery manufacturing methods]

[0116] Figure 4 This is a schematic flowchart illustrating a battery fabrication method according to an embodiment of this application. (In conjunction with...) Figure 4 As shown, the battery preparation method 200 may include the following steps.

[0117] Step 210: Provide a housing to prepare the battery.

[0118] The casing is used to house individual battery cells.

[0119] The enclosure includes: providing multiple walls, at least one of the multiple walls including a substrate and a coating disposed on at least one side of the substrate, wherein the water contact angle θ of the coating satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°; and enclosing the multiple walls to form the enclosure.

[0120] In the battery manufacturing method of this application embodiment, the water contact angle of the coating on the wall of the battery casing satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°. Therefore, it has good hydrophobicity, allowing the battery casing to have good hydrophobicity, reducing the possibility of water droplets adhering to the wall of the battery casing, thereby reducing the risk of the coating surface freezing at low temperatures due to adhering water droplets. When the battery is applied to an electrical device, it can improve the ease of operation and efficiency of battery replacement.

[0121] In some embodiments, providing a plurality of walls includes: mixing polyamide and hydrophobic silica to obtain a coating slurry, wherein the polyamide has a volume average particle size Dv50. 1 Satisfies: 30μm≤Dv50 1 ≤100μm, volume average particle size Dv50 of hydrophobic silica 2 Satisfies: 100nm≤Dv50 2 ≤200nm; The coating slurry is applied to at least one side of the surface of the substrate to form a wall.

[0122] In the battery preparation method of this application embodiment, the housing prepared by mixing polyamide and hydrophobic silica has good impact resistance, superhydrophobicity and anti-icing properties. The battery with this housing is used in electrical devices, which is beneficial for the battery swapping operation of electrical devices in low temperature environments.

[0123] As an example, a coating paste is applied to both sides of the substrate to form the walls of the housing.

[0124] The following describes embodiments of the battery cells of this application.

[0125] [Battery cell]

[0126] Typically, a battery cell includes a positive electrode, a negative electrode, an electrolyte, and a separator. During the charging and discharging process, active ions move back and forth between the positive and negative electrodes, inserting and extracting. The electrolyte acts as a conductor between the positive and negative electrodes. The separator, located between the positive and negative electrodes, primarily prevents short circuits while allowing active ions to pass through. In some embodiments, this battery cell is also referred to as a secondary battery, and the battery cell can be the smallest possible battery unit.

[0127] During the charging process of a lithium-ion battery, lithium ions are released from the positive electrode active material, move and embed into the negative electrode material; while during the discharging process, lithium ions are released from the negative electrode material, move and embed into the positive electrode active material.

[0128] It should be understood that the “intercalation” process described in this application refers to the process in which lithium ions are intercalated into the positive electrode active material and the negative electrode material due to an electrochemical reaction, and the “deintercalation” and “deintercalation” processes described in this application refer to the process in which lithium ions are deintercalated into the positive electrode active material and the negative electrode material due to an electrochemical reaction.

[0129] [Positive electrode plate]

[0130] The positive electrode includes a positive current collector and a positive electrode film layer disposed on at least one surface of the positive current collector, the positive electrode film layer including the positive electrode active material of the first aspect of this application.

[0131] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive electrode film layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0132] In some embodiments, the positive current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. The composite current collector may include a polymer substrate and a metal layer formed on at least one surface of the polymer substrate. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0133] In some embodiments, the positive electrode active material may be a known battery positive electrode active material. As an example, the positive electrode active material may include at least one of the following materials: lithium phosphates with an olivine structure, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium transition metal oxides 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, and lithium nickel cobalt manganese oxides (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al0.05 At least one of O2 and its modified compounds. Examples of lithium phosphates with an olivine structure include, but are not limited to, 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.

[0134] In some embodiments, the positive electrode film layer may optionally include a binder. As an example, the binder may include at least one selected from polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), PVDF-tetrafluoroethylene-propylene terpolymer, PVDF-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resin.

[0135] In some embodiments, the positive electrode film may optionally include a conductive agent. As an example, the conductive agent may include at least one selected from superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0136] In some embodiments, the positive electrode sheet can be prepared by dispersing the above-mentioned components for preparing the positive electrode sheet, such as positive active material, conductive agent, binder and any other components, in a solvent (e.g., N-methylpyrrolidone) to form a positive electrode slurry; coating the positive electrode slurry onto the positive electrode current collector, and then obtaining the positive electrode sheet after drying, cold pressing and other processes.

[0137] During the charging and discharging process of a battery, Li undergoes insertion / extraction and consumption, resulting in varying molar Li content at different discharge states. In the examples of cathode materials in this application, the molar Li content refers to the initial state of the material, i.e., the state before feeding. When the cathode material is applied to the battery system, the molar Li content changes after charge-discharge cycles.

[0138] In the examples of cathode materials in this application, the molar content of O is only a theoretical value. Oxygen release from the crystal lattice will cause changes in the molar content of oxygen, and the actual molar content of O will fluctuate.

[0139] [Negative electrode plate]

[0140] The negative electrode sheet includes a negative current collector and a negative electrode film layer disposed on at least one surface of the negative current collector, the negative electrode film layer including a negative electrode active material.

[0141] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode film layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0142] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. The composite current collector may include a polymer substrate and a metal layer formed on at least one surface of the polymer substrate. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0143] In some embodiments, the negative electrode active material may be a negative electrode active material known in the art for use in batteries. 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. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material 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 batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0144] In some embodiments, the negative electrode film layer may optionally include a binder. The binder may be selected from at least one of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0145] In some embodiments, the negative electrode film may optionally include a conductive agent. The conductive agent may be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0146] In some embodiments, the negative electrode film may optionally include other additives, such as thickeners (e.g., sodium carboxymethyl cellulose (CMC-Na)).

[0147] In some embodiments, the negative electrode sheet can be prepared by dispersing the components used to prepare the negative electrode sheet, such as the negative electrode active material, conductive agent, binder and any other components, in a solvent (e.g., deionized water) to form a negative electrode slurry; coating the negative electrode slurry onto the negative electrode current collector, and then obtaining the negative electrode sheet after drying, cold pressing and other processes.

[0148] [Electrolytes]

[0149] The electrolyte 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. For example, the electrolyte can be liquid, gel-like, or entirely solid.

[0150] In some embodiments, the electrolyte is an electrolyte solution. The electrolyte solution includes an electrolyte salt and a solvent.

[0151] Electrolyte salts may include one or more 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.

[0152] Solvents may include one or more of the following: 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.

[0153] The electrolyte may also optionally include negative electrode film-forming additives, positive electrode film-forming additives, and performance additives that can improve certain battery performance, such as performance additives that improve battery overcharge performance, battery high temperature or low temperature performance, etc.

[0154] [Isolation Component]

[0155] The separator is used to isolate the positive electrode and the negative electrode. This application does not impose any particular limitation on the type of separator; any known porous separator with good chemical and mechanical stability can be selected.

[0156] The material of the separator can be selected from one or more of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film; there are no particular restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different; there are no particular restrictions.

[0157] Positive electrode, negative electrode and separator can be made into electrode assembly by winding process or stacking process.

[0158] This application does not impose any particular limitation on the shape of the battery cell; it can be cylindrical, square, or any other arbitrary shape. The battery cell can be a lithium-ion battery, a lithium-sulfur battery, a sodium-ion battery, a magnesium-ion battery, etc.

[0159] Figure 5This is a schematic diagram of a battery cell according to an embodiment of this application. For example, as shown... Figure 5 As shown, the battery cell 3 is a square battery cell. The battery cell 3 includes a housing 31, an end cap assembly 32, and an electrode assembly 33 disposed in the housing 31.

[0160] The electrode assembly 33 can be made from a positive electrode, a negative electrode, and a separator through a winding process or a stacking process.

[0161] End cap assembly 32 includes electrode terminals 322, such as Figure 5 As shown, the end cap assembly 32 includes two electrode terminals 322, one of which is a positive electrode terminal and the other is a negative electrode terminal.

[0162] The battery cell 3 also includes a current collector 34, which is used to connect the tab 332 and the electrode terminal 322 of the electrode assembly 33. For example, in the case of a positive electrode in this embodiment, one current collector 34 is used to connect the tab and the positive electrode terminal of the positive electrode, and another current collector 34 is used to connect the tab and the negative electrode terminal of the negative electrode.

[0163] In some embodiments, the battery cell 3 includes an electrode assembly 33, which includes an electrode assembly body 331 and a tab 332 extending from the electrode assembly body 331.

[0164] In some embodiments, individual battery cells can be assembled into a battery module. The number of individual battery cells contained in a battery module can be one or more, and the specific number can be selected by those skilled in the art based on the application and capacity of the battery module.

[0165] [Electrical appliances]

[0166] This application provides an electrical device, including the battery described in the above embodiments. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0167] In some embodiments, the electrical device includes a heavy-duty truck. Heavy-duty trucks operate in complex and harsh environments, and their battery housings are more susceptible to impacts from gravel, which can even damage the coating and cause the housing to lose its hydrophobic and anti-icing properties. Heavy-duty trucks have high requirements for the impact resistance of the battery housings, as well as their hydrophobicity and anti-icing properties in low-temperature environments. Applying batteries to electrical devices such as heavy-duty trucks is beneficial for battery swapping operations in low-temperature environments.

[0168] Figure 6 This is a schematic diagram of an electrical device according to an embodiment of this application. Figure 6 As shown, this application provides an electrical device, which is a heavy-duty truck 6. The battery in the heavy-duty truck 6 can be replaced by a battery swapping device to replace the battery with insufficient power with a fully charged battery.

[0169] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0170] [Examples and Comparative Examples]

[0171] Example 1:

[0172] In a 250ml flask, add 20ml of the main solvent (butyl acetate) and 15ml of the auxiliary solvent (propylene glycol dimethyl ether acetate) sequentially, and stir until homogeneous. While stirring, add 24g of acrylate-modified polytetrafluoroethylene and 8g of the first component of the polyurethane adhesive (3000 molecular weight polyether polyol), and stir until homogeneous. While stirring, add 21g of polycaprolactam and 4.75g of fluorine-modified silica, and stir until homogeneous. While stirring, add 0.25g of deionized water and 0.25g of aminosilane coupling agent (aminopropyltriethoxysilane), and stir until homogeneous. Add 1g of thickener polypropylene to adjust the slurry viscosity to 300mPa·s. Then add 1.5g of the second component of the polyurethane adhesive (isophorone diisocyanate (IPDI)), and stir until homogeneous to form the coating slurry. The volume average particle size of the polycaprolactam is Dv50. 1 The volume average particle size (Dv50) of fluorine-modified silica is 40 μm. 2 The wavelength is 170 nm; based on the total weight of fluorine-modified silica, the weight percentage of fluorine, P2, is 8%.

[0173] The coating slurry prepared above was scraped onto an aluminum substrate and baked at 80°C for 2 hours to obtain wall 1, which is Example 1. In this example, the water contact angle θ of the coating on wall 1 is 151°, the water roll-off angle α is 10°, and the impact strength K is 150 kJ / m. 2 Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 8%.

[0174] Example 2: The preparation of Example 2 is similar to that of Example 1, except that the volume average particle size Dv50 of polycaprolactam is different. 1 The volume average particle size (Dv50) of fluorine-modified silica is 100 μm. 2The wavelength is 200 nm. In Example 2, the water contact angle θ of the coating on wall 2 is 165°, the water roll-off angle α is 5°, and the impact strength K is 100 kJ / m. 2 Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 24%.

[0175] Example 3: The preparation of Example 3 is similar to that of Example 1, except that the volume average particle size Dv50 of polycaprolactam is... 1 The volume average particle size (Dv50) of fluorine-modified silica is 30 μm. 2 The thickness is 100 nm. In Example 3, the water contact angle θ of the coating on wall 3 is 154°, the water roll-off angle α is 9°, and the impact strength K is 150 kJ / m. 2 Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 16%.

[0176] Example 4: The preparation of Example 4 is similar to that of Example 1, except that the volume average particle size Dv50 of polycaprolactam is... 1 The volume average particle size (Dv50) of fluorine-modified silica is 100 μm. 2 The wavelength is 200 nm. In Example 4, the water contact angle θ of the coating on wall 4 is 159°, the water roll-off angle α is 7°, and the impact strength K is 120 kJ / m. 2 Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 16%.

[0177] Example 5: The preparation of Example 5 is similar to that of Example 1, except that the volume average particle size Dv50 of polycaprolactam is... 1 The volume average particle size (Dv50) of fluorine-modified silica is 60 μm. 2 The thickness is 150 nm. In Example 5, the water contact angle θ of the coating on wall 5 is 155°, the water roll-off angle α is 8°, and the impact strength K is 140 kJ / m. 2 Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 16%.

[0178] Example 6: The preparation of Example 6 is similar to that of Example 5, except that the water contact angle θ of the coating on wall 6 in Example 6 is 151°, the water roll-off angle α is 9°, and the impact strength K is 170 kJ / m. 2 Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 8%.

[0179] Example 7: The preparation of Example 7 is similar to that of Example 5, except that the water contact angle θ of the coating on wall 7 in Example 7 is 160°, the water roll-off angle α is 6°, and the impact strength K is 110 kJ / m. 2Based on the total weight of the coating, the weight percentage of fluorine-modified silica, P1, is 24%.

[0180] Example 8: The preparation of Example 8 is similar to that of Example 5, except that polydodecylamide is used in the preparation of the coating slurry. In Example 8, the water contact angle θ of the coating on wall 8 is 156°, the water roll-off angle α is 8°, and the impact strength K is 130 kJ / m. 2 .

[0181] Comparative Example 1: The preparation of Comparative Example 1 was similar to that of Example 1, except that the volume average particle size Dv50 of the polycaprolactam was [not specified]. 1 The volume average particle size (Dv50) of fluorine-modified silica is 5 μm. 2 The coating thickness is 500 nm. In Comparative Example 1, the water contact angle θ of the coating on wall 9 is 132°, the water roll-off angle α is 27°, and the impact strength K is 70 kJ / m. 2 Based on the total weight of the coating, the weight percentage P1 of fluorine-modified silica is 3.5%.

[0182] The product parameters and performance parameters of Examples 1-8 and Comparative Example 1 are detailed in Table 1 below.

[0183] Table 1. Product parameters and performance parameters of Examples 1-8 and Comparative Example 1

[0184]

[0185]

[0186] In Table 1, θ represents the water contact angle of the coating, α represents the water roll-off angle of the coating, K represents the impact strength of the coating, and Dv50 1 Dv50 represents the volume average particle size of polyamide. 2 P1 represents the volume average particle size of the fluorinated silica. P1 represents the weight percentage of the fluorinated silica based on the total mass of the coating.

[0187] A comparison of the results from Examples 1-8 with Comparative Example 1 shows that the volume average particle size Dv50 of the polyamide in the coating is... 1 Satisfies: 30μm≤Dv50 1 ≤100μm, and the volume average particle size Dv50 of hydrophobic silica. 2 Satisfies: 100nm≤Dv50 2 When the thickness is ≤200nm, the water contact angle θ of the coating satisfies: θ≥150°, the water roll-off angle α of the coating satisfies: α≤10°, the coating has superhydrophobicity, and the coating has greater impact strength and better impact resistance.

[0188] The results of Examples 5-7 show that as the content of hydrophobic silica in the coating increases, the hydrophobicity of the coating is better (the water contact angle is larger and the water roll-off angle is smaller), but its impact strength decreases, that is, its impact resistance is reduced. Therefore, setting the content of hydrophobic silica in the coating within a suitable range can balance the hydrophobicity and impact resistance of the coating.

[0189] The following is a brief description of the testing methods for the physicochemical and performance parameters involved in the embodiments of this application. It should be understood that the following testing methods are only examples, and other testing methods known in the art can also be used for testing.

[0190] 1. Water contact angle test

[0191] In this embodiment of the application, the water contact angle of the coating on the wall is tested. The specific test method can be referred to the national standard GB / T 30693-2014 "Measurement of the contact angle between plastic film and water".

[0192] 2. Water roll-off angle test

[0193] In this embodiment of the application, the water roll-off angle of the coating on the wall is tested. The specific test method can be referred to the national standard GB / T 42694-2023 "Detection and evaluation of the anti-wetting properties of textile surfaces".

[0194] 3. Impact strength test

[0195] In this embodiment, the impact strength test of the coating on the wall is performed according to the national standard GB / T 1732-2020 "Test Method for Impact Resistance of Coating Film". The kinetic energy is calculated using the formula E. 动 = m * g * h, where m is the mass of the falling hammer, g is the acceleration due to gravity, and h is the impact height. The formula for calculating impact strength K is K = E. 动 / S, where S is the impact contact area.

[0196] 4. Adhesion rating test

[0197] The adhesion grade was tested using the cross-cut adhesion test (referencing national standard GB / T 9286-2021). Specifically, a substrate sample larger than 10cm x 10cm was selected, and a cross-cut adhesion tester was used to cut a cross pattern on the coating, with the cuts extending to the bottom layer of the coating. Then, a brush was used to brush five or six times along each diagonal direction to remove small debris. Next, adhesive tape was applied to the cuts and then removed. Finally, the condition of the cross-cut area was observed using a magnifying glass to evaluate the coating's adhesion. Adhesion grade classifications are shown in Table 2 below.

[0198] Table 2 Adhesion Level Table

[0199]

[0200] 5. Identification of substances in the coating

[0201] Fourier transform infrared spectroscopy was used to confirm the presence of polyamide, silica, and polyurethane in the coating. Specifically, a coating sample was taken, dried to remove moisture, and Fourier transform infrared spectroscopy was performed in reflectance mode at 25°C, 525–4000 cm⁻¹. -1 Infrared spectra were obtained under the test conditions, and the wavelength absorption characteristic peaks of the infrared spectra were analyzed.

[0202] (1) Approximately 1099cm -1 When a distinct Si-O stretching vibration peak appears, it is speculated that the coating contains silicon dioxide.

[0203] (2) Approximately 1730cm -1 The presence of a C=O stretching vibration peak at 1730 cm⁻¹ suggests the presence of polyamide and polyurethane in the coating; -1 The C=O stretching vibration peak at this point is a typical absorption peak for urethane and amino groups in polyamides and polyurethanes.

[0204] (3) Approximately 1600cm -1 The presence of NH bending vibration peaks can help prove that the coating may contain polyamide and polyurethane.

[0205] (4) 3300cm -1 The presence of a distinct single peak in the stretching vibration of a secondary amine can help prove that the coating may contain polyamide and polyurethane.

[0206] (5) At 1200-1350cm -1 The presence of a CN stretching vibration peak at this location is another typical absorption peak for polyamides and polyurethanes, further confirming that the coating contains polyamides and polyurethanes.

[0207] (6) Approximately 1500cm -1 When a CC stretching vibration peak appears, it is speculated that the coating contains alkane.

[0208] (7) In the range of 2950-3020cm -1 When a CH stretching vibration peak appears, it is speculated that the coating contains alkane.

[0209] For example, such as Figure 7 The image shown is a Fourier transform infrared spectrum of the substance in the coating in Example 1 of this application.

[0210] 6. Methods for determining the content of polyurethane and silica in coatings

[0211] Infrared spectroscopy and thermogravimetric analysis (TGA) can be used to determine the content of a material. Taking TGA as an example, since the residual TGA content of different materials (polyurethane, silica) is different and fixed, the content of the corresponding material is determined by comparing the residual TGA obtained from the test sample with the residual TGA content of a reference material, given the known TGA data for the corresponding material. The specific testing process is as follows: First, the weight percentage of silica in the coating is set to 10% (denoted as I), and different weight percentages of polyurethane in the coating (5%, 6%, 7%, 8%, and 9%, denoted as II) are tested for TGA. The test parameters are: heating rate 10℃ / min, temperature range 50-600℃. Then, a graph is plotted with the proportion of component II as the x-axis and the residual TGA a as the y-axis, and linear fitting is performed to obtain the fitting formula. Since the silica content I is a fixed value of 10%, this formula represents the relationship between different polyurethane content proportions and the infrared spectrum. Based on the calculated fit, the fitted formula obtained in this application is a = -2.21x + 43.31. The sample containing the content to be measured is subjected to the same thermogravimetric test, and the measured value of a is substituted into the formula to calculate the result x. The resulting value is the polyurethane content. Similarly, the silica content can be obtained.

[0212] 7. Test of volume average particle size

[0213] The volume average particle size Dv50 can be determined by measuring the raw materials used to prepare the coating. For example, it can be determined by laser particle size analyzer according to GB / T 19077-2016 Particle Size Distribution Laser Diffraction Method.

[0214] In addition, the coating of the substrate can be observed using a scanning electron microscope. A specific area can be selected, and the volume average particle size can be calculated based on the size and number of particles observed in that area.

[0215] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A battery, characterized in that, include: Battery cell; A housing for housing the individual battery cells; The box body includes multiple walls that enclose the box body. At least one of the multiple walls includes a substrate and a coating disposed on at least one side of the substrate. The water contact angle θ of the coating satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°.

2. The battery according to claim 1, characterized in that, The impact strength K of the coating satisfies: 100 kJ / m 2 ≤K≤200kJ / m 2 .

3. The battery according to claim 1 or 2, characterized in that, The coating comprises polyamide and hydrophobic silica, wherein the polyamide has a volume average particle size Dv50. 1 Satisfies: 30μm≤Dv50 1 The volume average particle size Dv50 of the hydrophobic silica is ≤100μm. 2 Satisfies: 100nm≤Dv50 2 ≤200nm.

4. The battery according to claim 3, characterized in that, Based on the total weight of the coating, the weight percentage P1 of the hydrophobic silica satisfies: 8% ≤ P1 ≤ 24%.

5. The battery according to claim 3 or 4, characterized in that, The polyamide includes at least one of polycaprolactam, polydodecanolactam, and polyhexamethylene adipamide.

6. The battery according to any one of claims 3 to 5, characterized in that, The hydrophobic silica includes fluorine-modified silica.

7. The battery according to claim 6, characterized in that, Based on the total weight of the fluorine-modified silica, the weight percentage of fluorine, P2, satisfies: 0.8% ≤ P2 ≤ 8%.

8. The battery according to any one of claims 1 to 7, characterized in that, The coating also includes an adhesive, which includes polytetrafluoroethylene resin and polyurethane.

9. The battery according to claim 8, characterized in that, The polytetrafluoroethylene resin includes acrylate-modified polytetrafluoroethylene.

10. The battery according to any one of claims 1 to 9, characterized in that, The coating also includes an interface modifier, which includes an amino-containing silane coupling agent.

11. The battery according to claim 10, characterized in that, The amino-containing silane coupling agent includes at least one of aminopropyltriethoxysilane, aminobutyltriethoxysilane, aminopropyltrimethoxysilane, and aminobutyltrimethoxysilane.

12. The battery according to any one of claims 1 to 11, characterized in that, The coating also includes a thickener, which includes at least one of polypropylene, polyethylene, and polyvinyl chloride.

13. The battery according to any one of claims 1 to 12, characterized in that, The thickness L of the coating satisfies: 60μm≤L≤100μm.

14. The battery according to any one of claims 1 to 13, characterized in that, The substrate includes aluminum alloy.

15. The battery according to any one of claims 1 to 14, characterized in that, The battery is disposed above the chassis of the power device. The housing includes a bottom wall, which is disposed opposite to the chassis. The bottom wall includes the substrate and the coating disposed on the surface of the substrate near the chassis.

16. A method for preparing a battery, characterized in that, include: A housing is provided for manufacturing the battery, wherein the housing is used to house individual battery cells; The provided housing includes: A plurality of walls are provided, at least one of the plurality of walls comprising a substrate and a coating disposed on at least one surface of the substrate, wherein the water contact angle θ of the coating satisfies: θ≥150°, and the water roll-off angle α of the coating satisfies: α≤10°. The plurality of walls are enclosed to form the box.

17. The preparation method according to claim 16, characterized in that, The provision includes multiple walls, including: Polyamide and hydrophobic silica are mixed to obtain a slurry for the coating, wherein the polyamide has a volume average particle size Dv50. 1 Satisfies: 30μm≤Dv50 1 The volume average particle size Dv50 of the hydrophobic silica is ≤100μm. 2 Satisfies: 100nm≤Dv50 2 ≤200nm; The coating slurry is applied to at least one side of the surface of the substrate to form the wall.

18. An electrical appliance, characterized in that, include: The battery according to any one of claims 1-15, and / or the battery obtained by the preparation method according to claim 16 or 17.

19. The electrical appliance according to claim 18, characterized in that, The electrical equipment includes heavy-duty trucks.

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