Aerogel heat insulation pad with heat conduction layer and preparation method of aerogel heat insulation pad

Abstract

The invention discloses an aerogel heat insulation pad with a heat conduction layer and a preparation method of the aerogel heat insulation pad. The heat insulation pad is formed by clamping a heat conduction layer between two aerogel layers, and the heat conduction layer can disperse heat to the whole plane from a local concentration point and dissipate the heat to the air through the aerogel layers. By optimizing the material and structural design of the heat conduction layer, the heat dissipation and soaking capacity of the aerogel layer in the cross section direction is remarkably improved, and meanwhile the heat insulation performance of aerogel is reserved. The heat insulation pad has excellent heat management performance and is suitable for the fields of electronic equipment heat dissipation, aerospace heat management, building heat preservation and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite material preparation, in particular to an aerogel thermal insulation pad with a heat-conducting layer and a preparation method thereof. BACKGROUND

[0002] Due to its three-dimensional nano-porous structure, aerogel has the characteristics of low density, high specific surface area, high porosity and pore volume. Therefore, aerogel is currently the solid material with the lowest thermal conductivity and the best thermal insulation performance. Due to its excellent performance of maintaining high-efficiency thermal insulation under extreme environmental conditions, it is widely used in the fields of aerospace and military.

[0003] In recent years, aerogel composite materials have also been widely used in the field of new energy vehicle manufacturing, especially in the design of battery systems, as a key thermal insulation and fireproof barrier layer, thereby significantly improving the overall safety and reliability of the battery system of new energy vehicles.

[0004] Although aerogel has excellent longitudinal thermal insulation capacity, it is difficult to disperse local heat accumulation, and after reaching the limit, the failure of the aerogel thermal insulation pad will lead to thermal runaway. SUMMARY

[0005] The purpose of the present application is to overcome the poor heat dissipation capacity of the aerogel thermal insulation pad in the prior art, and to provide an aerogel thermal insulation pad with a heat-conducting layer, which can improve the heat dissipation of the aerogel thermal insulation pad and reduce the risk of thermal runaway. The gel thermal insulation pad prepared by the present application has good longitudinal thermal insulation capacity and transverse heat dissipation capacity, and is suitable for the field of high-temperature thermal insulation between battery cells and thermal runaway.

[0006] To solve the above technical problems, the present application provides an aerogel thermal insulation pad with a heat-conducting layer, comprising two aerogel layers and a heat-conducting layer sandwiched therebetween, the heat-conducting layer is combined with the aerogel layer by an adhesive, the heat-conducting layer is used to increase the heat dissipation in the transverse cross-sectional direction and the heat uniformity in the longitudinal cross-sectional direction, so as to disperse the heat from the local concentration point to the entire plane, thereby rapidly spreading the heat to the low thermal resistance area.

[0007] Preferably, the material of the heat-conducting layer is graphene, metal foil or silicon carbide.

[0008] Preferably, the aerogel layer is a silica aerogel or an alumina aerogel.

[0009] Preferably, the thickness of the aerogel layer is 0.5-2mm, and the thickness of the heat-conducting layer is 1-4mm.

[0010] Preferably, the shape of the heat-conducting layer is a continuous film, a grid or a dot matrix.

[0011] The application also provides a preparation method of the aerogel thermal insulation pad with the heat conduction layer, comprising the following steps: Step A: dipping the base material into the sol to obtain the aerogel layer after gelation, modification and drying; Step B: fixing the heat conduction layer between the two aerogel layers by the adhesive; Step C: obtaining the aerogel thermal insulation pad by film sealing treatment of the aerogel layer.

[0012] Preferably, in step A, the base material for preparing the aerogel layer is polyacrylonitrile fiber felt, glass fiber felt, aluminum silicate fiber felt or mullite fiber felt; and the sol for preparing the aerogel layer is silicon sol, aluminum sol, titanium sol, silicon-aluminum sol or silicon-titanium sol.

[0013] Preferably, in step A, the modification method for preparing the aerogel layer is placing the gel in a modification solution or doping a modifier in the sol; and the drying method for preparing the aerogel layer is freeze drying, normal pressure drying or supercritical drying.

[0014] Preferably, in step B, the film for preparing the aerogel thermal insulation pad is PI film, PET film, PP film, PE film or PVC film; and the adhesive is epoxy resin, acrylate or cyanoacrylate.

[0015] Preferably, in step C, the film sealing temperature is 70-200℃, the film sealing pressure is 0-10MPa, and the time is 0-100s.

[0016] Compared with the prior art, the application has the following beneficial effects: 1. The application increases the heat conduction layer to disperse the local heat to the whole surface, thereby improving the utilization rate of the aerogel thermal insulation pad, and disperses the heat to the low thermal resistance area through the cross section to reduce the local heat accumulation and the risk of thermal runaway. 2. The application optimizes the material and structure design of the heat conduction layer, significantly improves the heat dissipation and heat distribution capacity of the aerogel in the cross section direction, and retains the thermal insulation performance of the aerogel. The composite material has excellent thermal management performance and is suitable for electronic equipment heat dissipation, aerospace thermal management, building thermal insulation and other fields. DETAILED DESCRIPTION

[0017] The advantages and features of the application will be more apparent from the following description and claims. In addition, the features, operations and characteristics described in the description can be combined in any appropriate manner to form various embodiments. Similarly, the steps or actions described in the method can be sequentially adjusted in a manner easily seen by those skilled in the art. Therefore, the order in the description is only for the purpose of clear description of a certain embodiment, and is not necessarily the order, unless otherwise stated that a certain order must be followed.

[0018] Example 1 The present application provides a preparation method of aerogel thermal insulation pad with thermal conductive layer, which is composed of two layers of aerogel layers sandwiching a thermal conductive layer, and the preparation method is as follows: (1) Soak 1mm polyacrylonitrile fiber felt in silica sol, and after gelation, modification and CO2 supercritical drying, obtain polyacrylonitrile fiber felt composite silicon oxide aerogel.

[0019] (2) Use PI film on the polyacrylonitrile fiber felt composite silicon oxide aerogel, and package at 70℃ and 2MPa pressure for 10s to obtain silicon oxide aerogel thermal insulation pad.

[0020] (3) Bond 2mm sheet-shaped silicon carbide on both sides of the aerogel layer by epoxy resin to obtain aerogel thermal insulation pad with thermal conductive layer to enhance the cross-section heat dissipation performance. The longitudinal thermal conductivity is 0.03W / (m·K), and the transverse thermal conductivity is 20W / (m·K).

[0021] The longitudinal thermal conductivity without thermal conductive layer is 0.017 W / (m·K), and the transverse thermal conductivity is 0.018 W / (m·K).

[0022] In step (1), the modification is to soak the wet gel after gelation in a modification liquid, wherein the modification liquid is dimethyldiethoxysilane.

[0023] Example 2 The present application also provides a preparation method of aerogel thermal insulation pad with thermal conductive layer, which is composed of two layers of aerogel layers sandwiching a thermal conductive layer, and the preparation method is as follows: (1) Soak 0.5mm glass fiber felt in aluminum sol, and after gelation, modification and normal pressure drying, obtain glass fiber felt composite aluminum oxide aerogel.

[0024] (2) Use PET film on the glass fiber felt composite aluminum oxide aerogel, and package at 100℃ and 1MPa pressure for 50s to obtain silicon oxide aerogel thermal insulation pad.

[0025] (3) Bond 2mm sheet-shaped copper sheet on both sides of the aerogel layer by acrylate to obtain aerogel thermal insulation pad with thermal conductive layer to enhance the cross-section heat dissipation performance. The longitudinal thermal conductivity is 0.2W / (m·K), and the transverse thermal conductivity is 10W / (m·K).

[0026] The longitudinal thermal conductivity without thermal conductive layer is 0.017 W / (m·K), and the transverse thermal conductivity is 0.018 W / (m·K).

[0027] The modification in step (1) is to immerse the gelled wet gel into a modification liquid, wherein the modification liquid is trimethylchlorosilane.

[0028] Example Three The application also provides a preparation method of aerogel thermal insulation pad with a thermal conductive layer, which is composed of two aerogel layers sandwiching a thermal conductive layer, and the preparation method is as follows: (1) Soak the 2mm ceramic fiber felt into the titanium sol, and after gelation, modification and freeze-drying, obtain the titanium oxide aerogel composite with the ceramic fiber felt.

[0029] (2) Use PP film to package the titanium oxide aerogel composite with the ceramic fiber felt at 70℃ and 7MPa pressure for 5s to obtain the titanium oxide aerogel thermal insulation pad.

[0030] (3) Bond the 2mm mesh aluminum sheet on both sides of the aerogel layer by cyanoacrylic acid to obtain the aerogel thermal insulation pad with a thermal conductive layer to enhance the cross-section heat dissipation performance. The longitudinal thermal conductivity is 0.4W / (m·K), and the transverse thermal conductivity is 15W / (m·K).

[0031] The longitudinal thermal conductivity without the thermal conductive layer is 0.017W / (m·K), and the transverse thermal conductivity is 0.018W / (m·K).

[0032] The modification in step (1) is to immerse the gelled wet gel into a modification liquid, wherein the modification liquid is hexamethyldisilazane.

[0033] The above description is only a description of the preferred embodiments of the application, and does not limit the scope of the application in any way. Any modification or modification made by a person skilled in the art according to the above disclosure is within the protection scope of the claims.

Claims

1. An aerogel thermal insulation pad with a thermally conductive layer, characterized in that, It includes two aerogel layers and a thermally conductive layer sandwiched between them. The thermally conductive layer is bonded to the aerogel layers by an adhesive. The thermally conductive layer is used to increase heat dissipation in the transverse cross-section and heat homogenization in the longitudinal cross-section, and can disperse heat from local concentration points to the entire plane, thereby rapidly diffusing heat to low thermal resistance areas.

2. The aerogel thermal insulation pad with a thermally conductive layer as described in claim 1, characterized in that, The thermally conductive layer is made of graphene, metal sheets, or silicon carbide.

3. The aerogel heat insulation pad with a thermally conductive layer as described in claim 1, characterized in that, The aerogel layer is silica aerogel or alumina aerogel.

4. The aerogel heat insulation pad with a thermally conductive layer as described in claim 1, characterized in that, The aerogel layer has a thickness of 0.5-2 mm, and the thermally conductive layer has a thickness of 1-4 mm.

5. The aerogel thermal insulation pad with a thermally conductive layer as described in claim 1, characterized in that, The thermally conductive layer is in the form of a continuous thin film, a mesh, or a lattice.

6. A method for preparing an aerogel heat insulation pad with a thermally conductive layer, characterized in that, Includes the following steps: Step A: The substrate is impregnated with sol, gelled, modified, and dried to obtain an aerogel layer; Step B: Fix the thermally conductive layer between the two aerogel layers using an adhesive; Step C: Seal the aerogel layer to obtain the aerogel heat insulation pad.

7. The method for preparing an aerogel heat insulation pad with a thermally conductive layer as described in claim 6, characterized in that, In step A, the substrate for preparing the aerogel layer is polyacrylonitrile fiber mat, glass fiber mat, aluminum silicate fiber mat, or mullite fiber mat; the sol for preparing the aerogel layer is silica sol, aluminum sol, titanium sol, silica-alumina sol, or silica-titanium sol.

8. The method for preparing an aerogel heat insulation pad with a thermally conductive layer as described in claim 6, characterized in that, In step A, the modification method for preparing the aerogel layer is to place the gel in a modification solution or to dope the sol with a modifier; the drying method for preparing the aerogel layer is freeze drying, atmospheric pressure drying or supercritical drying.

9. The method for preparing an aerogel heat insulation pad with a thermally conductive layer as described in claim 6, characterized in that, In step B, the membrane used to prepare the aerogel insulation pad is a PI film, PET film, PP film, PE film, or PVC film; the adhesive is an epoxy resin, acrylate, or cyanoacrylate.

10. The method for preparing an aerogel heat insulation pad with a thermally conductive layer as described in claim 6, characterized in that, In step C, the sealing temperature is 70-200℃, the sealing pressure is 0-10MPa, and the time is 0-100s.