Aerogel product with heat dissipation function, preparation method and application

Abstract

The present invention discloses an aerogel product with heat dissipation function, a preparation method and an application thereof, and relates to the technical field of thermal insulation materials. The aerogel product with heat dissipation function comprises a reinforcing substrate and an aerogel filled in the reinforcing substrate; the reinforcing substrate is composed of an inorganic fiber material and a heat-conducting mesh respectively compounded on the upper and lower surfaces of the inorganic fiber material. The preparation method of the aerogel product with heat dissipation function comprises the following steps: compounding a heat-conducting mesh on the upper and lower surfaces of the inorganic fiber material to obtain a reinforcing substrate; impregnating the reinforcing substrate with a sol treatment, and after gelation and drying, obtaining an aerogel product with heat dissipation function. The aerogel product of the present invention has both heat insulation function and a certain heat dissipation function. When the product is used between battery cells of a new energy battery pack, it can promote the heat between the battery cells to be dissipated through the heat-conducting mesh of the product, thereby avoiding the entire battery pack being in a heat concentration state due to excessive temperature on one side, which affects the safety performance.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal insulation materials, and in particular to an aerogel product with heat dissipation function, a preparation method and applications thereof. Background Art

[0002] Because new energy vehicles meet the environmental protection requirements strongly advocated by the government, their sales have increased annually and their application has expanded. Currently, the majority of new energy vehicles sold in the Chinese market are hybrid and pure electric vehicles, powered by lithium-ion batteries, nickel-metal hydride batteries, fuel cells, lead-acid batteries, and supercapacitors. Because vehicles require significant power to operate, electrically powered new energy vehicles require the battery compartment to provide a high current for extended periods of time to ensure proper operation. When the onboard battery outputs power for extended periods, the chemical reactions within the battery can cause significant heating, posing a risk of thermal runaway, such as combustion or explosion. Thermal runaway is the most serious safety issue for power batteries and poses a direct threat to user safety. Thermal protection technologies are primarily used to address the propagation of thermal runaway.

[0003] Current research on thermal runaway in power battery systems primarily focuses on safety issues related to thermal runaway, which is triggered by thermal runaway in a single cell and then propagates throughout the entire battery pack. This is because when a single cell triggers thermal runaway, heat generation surges, but the amount of heat dissipated is far less than the generated heat. This heat transfers to surrounding cells, rapidly triggering large-scale thermal runaway in surrounding batteries, leading to a series of chain reactions. In other words, thermal runaway in a single cell is the source of thermal runaway in the entire battery pack. Therefore, it is essential to equip electric vehicle power battery packs with a set of targeted battery insulation and heat dissipation materials. Good insulation and heat dissipation can improve the efficiency and service life of the entire power battery pack. Summary of the Invention

[0004] To solve the above problems, the present invention provides an aerogel product with heat dissipation function, a preparation method and an application. A thermal conductive mesh is compounded on the outside of the inorganic fiber material, and then the entire aerogel is impregnated with a sol treatment, so that the prepared aerogel product has both heat insulation function and a certain heat dissipation function. When the product is used between the battery cells of a new energy battery pack, the heat between the battery cells can be dissipated through the thermal conductive mesh of the product, avoiding the entire battery pack being in a heat concentration state due to excessive temperature on one side, which affects the safety performance.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] An aerogel product with heat dissipation function comprises a reinforcing substrate and an aerogel filled in the reinforcing substrate; the reinforcing substrate is composed of an inorganic fiber material and a heat-conducting mesh composited on the upper and lower surfaces of the inorganic fiber material.

[0007] A method for preparing an aerogel product with heat dissipation function comprises the following steps:

[0008] (1) Compounding a thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material to obtain a reinforced substrate;

[0009] (2) The reinforced substrate is impregnated with the sol, and after gelation and drying, an aerogel product with heat dissipation function is obtained.

[0010] Among them, in step (1), the specific operation of respectively compounding the thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material is: laying the thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material respectively, and then performing Z-direction needle punching with flexible fibers to compound the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforced substrate, wherein the upper and lower surfaces of the inorganic fiber material are the two surfaces with the largest surface area of ​​the inorganic fiber material.

[0011] Among them, the thermal conductive mesh is a metal fiber mesh or a graphene mesh; the metal fiber mesh includes an aluminum fiber mesh or a copper fiber mesh; the flexible fiber is one of glass fiber, polyester fiber, polyethylene fiber, polypropylene fiber, carbon fiber, aramid fiber, nylon fiber and biomass fiber.

[0012] The inorganic fiber material is inorganic fiber felt or inorganic fiber mesh; the inorganic fiber is glass fiber, pre-oxidized silk fiber, aluminum silicate fiber, basalt fiber or carbon fiber. In order to meet the thickness requirement, the inorganic fiber mesh can be stacked in multiple layers.

[0013] Wherein, in step (1), the thickness of the inorganic fiber material is 0.2-5 mm, and the thickness of the thermal conductive mesh is 0.2-2 mm.

[0014] Wherein, in step (2), a hydrophobic treatment is performed after the reinforcing substrate is impregnated with the sol and gelled, before drying, or after drying. The hydrophobic treatment is performed by immersing the material to be hydrophobized in a hydrophobizing agent or by introducing a gaseous hydrophobizing agent into the material to be hydrophobized;

[0015] Wherein, in step (2), the impregnation treatment can be performed by pouring, spraying, brushing, soaking or any combination thereof to apply the sol to the reinforcing substrate.

[0016] Wherein, in step (2), the sol includes silica sol, alumina sol or silica-alumina composite sol which can be prepared into aerogel.

[0017] Wherein, in step (2), the preparation step of the silica sol comprises: taking a silicon source, ethanol and water and mixing them evenly, then adding a catalyst and stirring them evenly to obtain the silica sol; wherein, the silica sol is obtained by mixing the silicon source: ethanol: water = 1: (2-60): (0.05-30) in a molar ratio; the silicon source is one or more of ethyl orthosilicate, methyl orthosilicate, butyl orthosilicate, isopropyl orthosilicate, and alkyl alkoxysilane; the alkyl alkoxysilane includes methyltrimethoxysilane, dimethyldimethoxysilane, The catalyst comprises one or more of triethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, vinyltriethoxysilane, propyltrimethoxysilane and propyltriethoxysilane; the catalyst comprises an alkaline catalyst, and the alkaline catalyst is one or a combination of two of sodium hydroxide, potassium hydroxide, ammonia water, ammonium fluoride, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, ethanolamine, diethanolamine, methylamine, dimethylamine, ethylamine, diethylamine, propylamine, dipropylamine, isopropanolamine, aniline, o-phenylenediamine, m-phenylenediamine and p-phenylenediamine.

[0018] The preparation step of the alumina sol includes: preparing an aluminum source, a chelating agent, a solvent for the alumina sol, water, and a catalyst for the alumina sol to obtain the alumina sol, wherein the molar ratio of the aluminum source, the chelating agent, the solvent for the alumina sol, the water, and the catalyst for the alumina sol is 1:(0.001-0.06):(4-32):(0.6-4):(0.0001-1); the aluminum source is one or a combination of two or more selected from aluminum isopropoxide, aluminum sec-butoxide, and aluminum nitrate; the chelating agent is one or a combination of two or more selected from the group consisting of acetylacetone and ethyl acetoacetate; the solvent for the alumina sol is one or a combination of two or more selected from the group consisting of ethanol, isopropanol, and n-butanol; and the catalyst for the alumina sol is one or a combination of two or more selected from the group consisting of sodium hydroxide, potassium hydroxide, aqueous ammonia, and ammonium fluoride;

[0019] The silica-alumina composite sol is prepared by uniformly mixing silica sol and alumina sol, or by directly and uniformly mixing precursor solutions used for the silica-alumina composite sol.

[0020] In step (2), the drying treatment adopts one of ethanol supercritical drying, CO2 supercritical drying, atmospheric pressure drying and freeze drying.

[0021] An aerogel product with heat dissipation function is applied in the field of new energy. The prepared aerogel product with heat dissipation function is cut into corresponding sizes and placed between the cells of a new energy battery pack for heat insulation and heat dissipation between the cells of the battery pack.

[0022] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0023] (1) In the present invention, a thermal conductive mesh is composited on the upper and lower surfaces of the inorganic fiber material to obtain a reinforced substrate, and then the material is impregnated with sol. During the impregnation process, since the selected thermal conductive mesh material itself is smooth, the impregnated sol will not combine with the thermal conductive mesh, and the impregnated sol will enter the interior of the fiber felt through the pores of the thermal conductive mesh material. Therefore, after the sol is gelled, the thermal conductive mesh on the outer surface will play a certain blocking role, so that the gel is fixed inside the fiber felt, thereby making the product have a certain anti-powdering effect; in addition, the thermal conductive mesh can be made of metal fiber mesh and graphene mesh film, among which the metal fiber mesh itself has the advantages of high tensile modulus and high tensile strength, which is beneficial to improving the tensile performance of aerogel products.

[0024] (2) In the present invention, the thermal conductive mesh material selected is a metal fiber mesh or a graphene mesh film, both of which have certain thermal conductivity and heat dissipation functions. The thermal conductive mesh is compounded on the outside of the inorganic fiber material so that the prepared aerogel material has both thermal insulation function and certain heat dissipation function. When this product is used between the battery cells of the new energy battery pack, the heat between the battery cells can be dissipated through the thermal conductive mesh of the product, thereby avoiding the entire battery pack being in a heat concentration state due to excessive temperature on one side, which affects the safety performance.

[0025] (3) Most of the thermal insulation and heat dissipation materials currently used in the new energy field are made by pasting a heat-conducting layer or a heat-dissipating layer on the outside of an aerogel felt with an adhesive. However, the present invention prepares an enhanced substrate by compounding a layer of heat-conducting mesh on the upper and lower surfaces of an inorganic fiber material, and then impregnating the inorganic fiber material and the heat-conducting mesh into a sol. This can avoid the use of adhesives and ensure the stability of the overall structure, thereby avoiding the phenomenon of powder loss in aerogel products, which may cause the heat-conducting layer to fall off. DETAILED DESCRIPTION

[0026] The following will be combined with specific embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1

[0028] This embodiment provides an aerogel product with heat dissipation function, including a reinforced substrate and an aerogel filled inside the reinforced substrate; a thermal conductive mesh is placed on the upper and lower surfaces of an inorganic fiber material, respectively, and then Z-direction needle punching is performed using flexible fibers to composite the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforced substrate.

[0029] The method for preparing an aerogel product with heat dissipation function in this embodiment includes the following steps:

[0030] (1) The thermal conductive mesh is laid on the upper and lower surfaces of the inorganic fiber material, and then the flexible fiber is needled in the Z direction to composite the thermal conductive mesh, the inorganic fiber material, and the thermal conductive mesh to obtain a reinforced substrate; the thickness of the inorganic fiber material in the reinforced substrate is 5 mm, and the thickness of the thermal conductive mesh is 0.5 mm;

[0031] (2) The reinforced substrate is impregnated with silica sol, and after gelation, hydrophobic treatment and CO2 supercritical drying, an aerogel product with heat dissipation function is obtained.

[0032] Wherein, in step (1), the thermal conductive mesh is a metal copper fiber mesh, the inorganic fiber material is a glass fiber mat, and the flexible fiber is a glass fiber. The metal copper fiber mesh is laid on the upper and lower surfaces of the glass fiber mat respectively, and is connected by Z-direction needle punching through the glass fiber. The Z-direction glass fiber is only needle-punched on the surface of the glass fiber mat and the metal copper fiber mesh, and does not completely penetrate the glass fiber mat, that is, 2.5D needle punching, so that the thermal conductive mesh-inorganic fiber material-thermal conductive mesh are composited to obtain a reinforced substrate.

[0033] In step (2), the impregnation treatment can be performed by pouring the silica sol onto the reinforced substrate. The silica sol is prepared by mixing a silicon source, ethanol, and water in a molar ratio of 1:30:12, and then adding an alkaline catalyst and stirring to obtain the silica sol. The silicon source is methyltrimethoxysilane, and the alkaline catalyst is a mixed solution of ammonia water and ammonium fluoride.

[0034] In step (2), the hydrophobic treatment is to soak the wet gel material obtained by impregnating the reinforced substrate with silica sol and then gelling it in a hydrophobic agent, and the hydrophobic agent selected is methyltrimethoxysilane solution.

[0035] Example 2

[0036] This embodiment provides an aerogel product with heat dissipation function, including a reinforced substrate and an aerogel filled inside the reinforced substrate; a thermal conductive mesh is placed on the upper and lower surfaces of an inorganic fiber material, respectively, and then Z-direction needle punching is performed using flexible fibers to composite the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforced substrate.

[0037] The method for preparing an aerogel product with heat dissipation function in this embodiment includes the following steps:

[0038] (1) The thermal conductive mesh is laid on the upper and lower surfaces of the inorganic fiber material, and then the flexible fiber is needled in the Z direction to composite the thermal conductive mesh, the inorganic fiber material, and the thermal conductive mesh to obtain a reinforced substrate; the thickness of the inorganic fiber material in the reinforced substrate is 0.5 mm, and the thickness of the thermal conductive mesh is 0.5 mm;

[0039] (2) The reinforced substrate is impregnated with alumina sol, and after gelation, hydrophobic treatment and normal pressure drying, an aerogel product with heat dissipation function is obtained.

[0040] Wherein, in step (1), the thermal conductive mesh is a metal aluminum fiber mesh, the inorganic fiber material is a pre-oxidized silk fiber felt, and the flexible fiber is an aramid fiber. The metal aluminum fiber mesh is laid on the upper and lower surfaces of the pre-oxidized silk fiber felt, respectively, and the reinforced substrate is connected by Z-direction needle punching through the aramid fiber. When the Z-direction aramid fiber is needle punched, the Z-direction aramid fiber directly penetrates the pre-oxidized silk fiber felt, that is, 3D needle punching, so that the thermal conductive mesh-inorganic fiber material-thermal conductive mesh are composited to obtain a reinforced substrate.

[0041] In step (2), the impregnation treatment can be performed by spraying to apply the alumina sol to the reinforced substrate, and the preparation steps of the alumina sol include: preparing an aluminum source, a chelating agent, a solvent for alumina sol, water and a catalyst for alumina sol to obtain the alumina sol, and the molar ratio of the aluminum source, the chelating agent, the solvent for alumina sol, water and the catalyst for alumina sol is 1:0.001:4:0.6:0.0001; and the specific preparation steps are: firstly mixing the aluminum source aluminum sec-butoxide and the chelating agent ethyl acetoacetate evenly, then adding the solvent ethanol for alumina sol and mixing evenly, and then adding water and the catalyst acetic acid for alumina sol and mixing evenly to obtain the alumina sol.

[0042] In step (2), the hydrophobic treatment is to soak the wet gel material obtained by impregnating the reinforced substrate with alumina sol and then treating it with gel in a hydrophobic agent. The hydrophobic agent selected is a mixed solution of three hydrophobic agents: methyltrimethoxysilane, dimethyldimethoxysilane and trimethylmethoxysilane.

[0043] Example 3

[0044] This embodiment provides an aerogel product with heat dissipation function, including a reinforced substrate and an aerogel filled inside the reinforced substrate; a thermal conductive mesh is placed on the upper and lower surfaces of an inorganic fiber material, respectively, and then Z-direction needle punching is performed using flexible fibers to composite the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforced substrate.

[0045] The method for preparing an aerogel product with heat dissipation function in this embodiment includes the following steps:

[0046] (1) The thermal conductive mesh is laid on the upper and lower surfaces of the inorganic fiber material, and then the flexible fiber is needled in the Z direction to make the thermal conductive mesh-inorganic fiber material-thermal conductive mesh composite to obtain a reinforced substrate; the thickness of the inorganic fiber material in the reinforced substrate is 2 mm, and the thickness of the thermal conductive mesh is 1 mm;

[0047] (2) The reinforced substrate is impregnated with silica sol, and after gelation, CO2 supercritical drying and hydrophobic treatment, an aerogel product with heat dissipation function is obtained.

[0048] Wherein, in step (1), the thermal conductive mesh is a metal copper fiber mesh, the inorganic fiber material is a glass fiber mesh, and the flexible fiber is a nylon fiber; the metal copper fiber mesh, multiple layers of glass fiber mesh and the metal copper fiber mesh are stacked and laid in sequence, and the reinforcing substrate is connected by Z-direction needle punching through the nylon fiber. When the Z-direction nylon fiber is needle punched, the Z-direction nylon fiber directly penetrates the entire reinforcing substrate, that is, 3D needle punching, so that the thermal conductive mesh-inorganic fiber material-thermal conductive mesh are compounded to obtain a reinforced substrate.

[0049] In step (2), the impregnation treatment can be performed by applying the silica sol to the reinforced substrate by brushing; the preparation steps of the silica sol include: mixing the silicon source: ethanol: water in a molar ratio of 1:60:30, and then adding an alkali catalyst and stirring evenly to obtain the silica sol, wherein the silicon source is a mixed solution of ethyl orthosilicate and methyl orthosilicate, and the alkali catalyst is a mixed solution of ammonia water and ammonium fluoride.

[0050] In step (2), the hydrophobic treatment is to introduce a gaseous hydrophobicizing agent into the aerogel material obtained by impregnating the reinforcing substrate with silica sol, gelling, and drying. The gaseous hydrophobicizing agent is obtained by heating and gasifying a liquid hydrophobicizing agent.

[0051] Example 4

[0052] This embodiment provides an aerogel product with heat dissipation function, including a reinforced substrate and an aerogel filled inside the reinforced substrate; a thermal conductive mesh is placed on the upper and lower surfaces of an inorganic fiber material, respectively, and then Z-direction needle punching is performed using flexible fibers to composite the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforced substrate.

[0053] The method for preparing an aerogel product with heat dissipation function in this embodiment includes the following steps:

[0054] (1) The thermal conductive mesh is placed on the upper and lower surfaces of the inorganic fiber material, and then the flexible fiber is needled in the Z direction to compound the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforced substrate; the thickness of the inorganic fiber material in the reinforced substrate is 0.2 mm, and the thickness of the thermal conductive mesh is 0.2 mm;

[0055] (2) The reinforced substrate is impregnated with a silicon-aluminum composite sol, and after gelation, hydrophobic treatment and ethanol supercritical drying, an aerogel product with heat dissipation function is obtained.

[0056] Wherein, in step (1), the thermal conductive mesh is a graphene mesh, the inorganic fiber material is an aluminum silicate fiber felt, and the flexible fiber is a polyester fiber; the graphene mesh, the multi-layer aluminum silicate fiber felt and the graphene mesh are stacked and laid in sequence, and the reinforced substrate is connected by Z-direction needle punching through the polyester fiber. The Z-direction polyester fiber is only needle-punched on the surface of the aluminum silicate fiber felt and the graphene mesh, and does not completely penetrate the aluminum silicate fiber felt, that is, 2.5D needle punching, so that the thermal conductive mesh-inorganic fiber material-thermal conductive mesh are compounded to obtain a reinforced substrate.

[0057] In step (2), the impregnation treatment can be performed by immersing the silica-aluminum composite sol onto the reinforced substrate. The steps of configuring the silica-aluminum composite sol include: (1) mixing the silicon source, ethanol, and water in a molar ratio of 1:40:15, and then adding an ammonium fluoride aqueous solution and stirring to obtain silica sol. The silicon source is a mixed silicon source of methyltrimethoxysilane, dimethyldimethoxysilane, and methyltriethoxysilane, and the base catalyst is an ammonium fluoride aqueous solution; (2) preparing an aluminum sol by mixing an aluminum source, a chelating agent, a solvent for aluminum sol, water, and a catalyst for aluminum sol. The molar ratio of the aluminum source, the chelating agent, the solvent for aluminum sol, water, and the catalyst for aluminum sol is 1:0.06:32:4:1; and (3) uniformly mixing the silica sol obtained in step (1) and the aluminum sol obtained in step (2) to obtain a silica-aluminum composite sol.

[0058] In step (2), the hydrophobic treatment is to introduce a gaseous hydrophobicizing agent into the wet gel material obtained by impregnating the reinforcing substrate with silica-alumina sol and then gelling it. The gaseous hydrophobicizing agent is obtained by heating and gasifying a liquid hydrophobicizing agent.

[0059] Example 5

[0060] The difference between this embodiment and the above-mentioned embodiment 1 is only that:

[0061] In step (1), the thickness of the inorganic fiber material in the base material is 2 mm, the thickness of the thermal conductive mesh is 2 mm, the inorganic fiber material is carbon fiber felt, the thermal conductive mesh is metal aluminum fiber mesh, and the flexible fiber is biomass bamboo fiber. The metal aluminum fiber mesh is laid on the upper and lower surfaces of the carbon fiber felt, and the reinforced substrate is connected by Z-direction needle punching through the biomass bamboo fiber. When the Z-direction biomass bamboo fiber is needle punched, the Z-direction biomass bamboo fiber directly penetrates the carbon fiber felt, that is, 3D needle punching, so that the thermal conductive mesh-inorganic fiber material-thermal conductive mesh are compounded to obtain a reinforced substrate.

[0062] In step (2), the impregnation treatment can be performed by spraying the silica sol onto the reinforced substrate. The silica sol preparation step includes: mixing the silicon source, ethanol, and water in a molar ratio of 1:2:0.05, and then adding an alkali catalyst and stirring to obtain the silica sol. The silicon source is a mixture of methyltrimethoxysilane, dimethyldimethoxysilane, and trimethylmethoxysilane in a molar ratio of 1:1:1, and the alkali catalyst is a mixed solution of methylamine and dimethylamine.

[0063] Example 6

[0064] The difference between this embodiment and the above-mentioned embodiment 1 is only that:

[0065] (1) Laying the thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material respectively, and then performing Z-direction needle punching with flexible fibers to composite the thermal conductive mesh, the inorganic fiber material, and the thermal conductive mesh to obtain a reinforced substrate;

[0066] (2) The reinforced substrate is impregnated with silica sol, and after gelation, CO2 supercritical drying and hydrophobic treatment, an aerogel product with heat dissipation function is obtained.

[0067] In step (1), the thickness of the inorganic fiber material in the base material is 3 mm, the thickness of the thermal conductive mesh is 1.5 mm, the thermal conductive mesh is a metal copper fiber mesh, the inorganic fiber material is a basalt fiber mesh, and the flexible fiber is a polyethylene fiber. The metal copper fiber mesh, multiple layers of basalt mesh and the metal copper fiber mesh are stacked and laid in sequence, and the reinforced substrate is connected by Z-direction needle punching through polypropylene fiber. When the Z-direction polypropylene fiber is needle punched, the Z-direction polypropylene fiber directly penetrates the entire reinforced substrate, that is, 3D needle punching, so that the thermal conductive mesh-inorganic fiber material-thermal conductive mesh are compounded to obtain a reinforced substrate.

[0068] In step (2), the hydrophobic treatment is to soak the aerogel material obtained by impregnating the reinforced substrate with silica sol, treating it with gel, and drying it in a hydrophobic agent. The hydrophobic agent selected is methyltrimethoxysilane solution. After the hydrophobic treatment, it is dried again to obtain an aerogel product.

[0069] Example 7

[0070] The only difference between this embodiment and the above-mentioned embodiment 1 is that: in step (1), the thickness of the inorganic fiber material is 1 mm, the thickness of the heat-conducting mesh is 1 mm; and the flexible fiber is polypropylene fiber.

[0071] In step (2), the impregnation treatment can be performed by applying the alumina sol to the reinforced substrate by immersion. The preparation step of the alumina sol includes: preparing an aluminum source, a chelating agent, a solvent for alumina sol, water, and a catalyst for alumina sol to obtain the alumina sol, wherein the molar ratio of the aluminum source, the chelating agent, the solvent for alumina sol, water, and the catalyst for alumina sol is 1:0.006:32:4:1; and the specific preparation steps are: firstly mixing the aluminum source aluminum isopropoxide and the chelating agent acetylacetone evenly, then adding the alumina sol solvent n-butanol and mixing evenly, and then adding water and the alumina sol catalyst ammonium fluoride and mixing evenly to obtain the alumina sol.

[0072] Application Examples

[0073] 1. When no insulation material is placed between the cells of a new energy battery pack, the surface temperature of the cells rises sharply at the beginning of discharge and reaches a maximum temperature of 250°C in 750s, which can easily cause thermal runaway of the battery.

[0074] 2. When placing an aerogel insulation layer between the cells of the new energy battery pack, the heat released by the cells is restricted by the insulation material, and the heat conduction rate is reduced. After 30 minutes, the temperature range of the cells on the side of the aerogel insulation layer is set to 125-180°C.

[0075] 3. The aerogel product with heat dissipation function prepared in the above embodiment was cut into corresponding sizes and placed between the battery cells of the new energy battery pack. After 30 minutes, the thermal insulation effect was further improved because the aerogel insulation material in the product reduced the heat conduction rate and the thermal conductive network on the surface increased the heat dissipation rate of the battery surface.

[0076] The temperature of the battery cell on one side of the product of Example 1 was set to be reduced to 90°C;

[0077] The temperature of the battery cell on one side of the product in Example 2 was set to 100°C;

[0078] The temperature of the battery cell on one side of the product of Example 3 was set to drop to 95°C;

[0079] The temperature of the battery cell on one side of the product of Example 4 was set to drop to 105°C;

[0080] The temperature of the battery cell on one side of the product of Example 5 was set to drop to 98°C;

[0081] The temperature of the battery cell on one side of the product of Example 6 was set to drop to 93°C;

[0082] The temperature of the battery cell on one side of the product of Example 7 was set to drop to 96°C. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. An aerogel product with heat dissipation function, characterized in that The invention comprises a reinforcing substrate and an aerogel filled in the reinforcing substrate; the reinforcing substrate is composed of an inorganic fiber material and a thermal conductive mesh composited on the upper and lower surfaces of the inorganic fiber material; the preparation method of an aerogel product with heat dissipation function comprises the following steps: (1) composite the thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material to obtain a reinforcing substrate; (2) impregnate the reinforcing substrate with a sol treatment, and after gelation and drying, obtain an aerogel product with heat dissipation function; the specific operation of composite the thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material is: laying the thermal conductive mesh on the upper and lower surfaces of the inorganic fiber material respectively, and then performing Z-direction needle punching with flexible fibers to composite the thermal conductive mesh-inorganic fiber material-thermal conductive mesh to obtain a reinforcing substrate, wherein the upper and lower surfaces of the inorganic fiber material are the two surfaces with the largest surface area of ​​the inorganic fiber material; the thermal conductive mesh is a metal fiber mesh or a graphene mesh film.

2. The aerogel product with heat dissipation function according to claim 1, characterized in that: The metal fiber mesh includes an aluminum fiber mesh or a copper fiber mesh; the flexible fiber is one of glass fiber, polyester fiber, polyethylene fiber, polypropylene fiber, carbon fiber, aramid fiber, nylon fiber and biomass fiber.

3. The aerogel product with heat dissipation function according to claim 1, characterized in that: The inorganic fiber material is inorganic fiber felt or inorganic fiber mesh; the inorganic fiber is glass fiber, pre-oxidized silk fiber, aluminum silicate fiber, basalt fiber or carbon fiber.

4. The aerogel product with heat dissipation function according to claim 1, characterized in that: In step (1), the thickness of the inorganic fiber material is 0.2-5 mm, and the thickness of the heat-conducting mesh is 0.2-2 mm.

5. The aerogel product with heat dissipation function according to claim 1, characterized in that: In step (2), a hydrophobic treatment is performed after the reinforcing substrate is impregnated with the sol and gelled, before drying, or after drying. The hydrophobic treatment is performed by immersing the material to be hydrophobized in a hydrophobic agent or by introducing a gaseous hydrophobic agent into the material to be hydrophobized.

6. The aerogel product with heat dissipation function according to claim 1, characterized in that: In step (2), the impregnation treatment may be performed by pouring, spraying, brushing, soaking or any combination thereof to apply the sol to the reinforcing substrate.

7. The aerogel product with heat dissipation function according to claim 1, characterized in that: In step (2), the sol includes silica sol, alumina sol or silica-alumina composite sol that can be prepared into aerogel.

8. An application of the aerogel product with heat dissipation function according to any one of claims 1 to 7 in the field of new energy, characterized in that The aerogel product is placed between the cells of the new energy battery pack to be used for heat insulation and heat dissipation between the cells of the battery pack.