The present application discloses a thermally insulating aerogel vacuum composite panel and a preparation method thereof. The preparation method includes the following steps: (1) mixing TEOS solution and a metal particle, adding a hydrophobic agent, mixing, adding ammonium trifluoroacetate solution dropwise until completely gelating to obtain a metal aerogel precursor; (2) adding the metal aerogel precursor into an acid replacement solution for replacement for 1-24 h to obtain a gel; (3) washing the gel with deionized water to obtain a neutral gel; (4) soaking the neutral gel obtained in step (3) in a first organic resin solvent; (5) pouring the neutral gel into a substrate with honeycomb structure, and aging for re-gelating to obtain a modified panel; (6) drying the modified panel to obtain a honeycomb panel; and (7) aging the honeycomb panel at room temperature for 1-24 h to obtain the vacuum composite panel.

A fiber sheet having first and second surfaces and spaces therein is prepared. The spaces of the fiber sheet are impregnated with silica sol containing water glass and ethylene carbonate. Silica gel is formed by causing the silica sol with which the spaces of the fiber sheet is impregnated to gel while a difference between respective temperatures at the first and surfaces of the fiber sheet is equal to or larger than 50° C. The silica gel is hydrophobized, thereby providing a thermal insulation sheet. In the thermal insulation sheet, compressibilities of the first and second surfaces for a predetermined pressure applied thereto are different from each other. The thermal insulation sheet may be disposed between two battery cells so as to prevent one sell from influencing the other even if the one expands.

A fiber sheet having first and second surfaces and spaces therein is prepared. The spaces of the fiber sheet are impregnated with silica sol containing water glass and ethylene carbonate. Silica gel is formed by causing the silica sol with which the spaces of the fiber sheet is impregnated to gel while a difference between respective temperatures at the first and surfaces of the fiber sheet is equal to or larger than 50° C. The silica gel is hydrophobized, thereby providing a thermal insulation sheet. In the thermal insulation sheet, compressibilities of the first and second surfaces for a predetermined pressure applied thereto are different from each other. The thermal insulation sheet may be disposed between two battery cells so as to prevent one sell from influencing the other even if the one expands.

A heat-insulating sheet includes a fiber sheet having spaces therein and silica xerogel held in the spaces. The heat-insulating sheet includes a high-compressive region and a low-compressive region. A compression rate of the high-compressive region of the heat-insulating sheet with respect to a pressure of 0.25 MPa applied to the high-compressive region is greater than or equal to 30% and less than or equal to 50%. A compression rate of the low-compressive region of the heat-insulating sheet with respect to a pressure of 0.25 MPa applied to the low-compressive region is greater than or equal to 1% and less than or equal to 5%. This heat-insulating sheet has large thermal insulation as a whole.

An aerogel and drying method, the aerogel having a larger size, good productivity, and high transparency. The aerogel has a silsesquioxane structure and exhibits two exothermic peaks observed in a temperature range of 300 to 600° C. as measured by TG-DTA (thermogravimetry-differential thermal analysis) under an inert gas atmosphere containing 80% by volume of an inert gas and 20% by volume of oxygen. A method for producing aerogel includes a drying step including a first step in which an aerogel which has undergone condensation of a hydrolysate is placed in a liquid phase system having a first liquid phase and a second liquid phase; a second step in which a first solvent constituting the first liquid phase is evaporated from the first liquid phase at a temperature greater than room temperature; and a third step in which heating is still continued after the first liquid phase is evaporated off.

A wet gel granule of aerogel is prepared by the following steps: mixing step: mixing with an organic mixed solvent to form a mixed solution; hydrolysis step: adding an acid catalyst to the mixed solution for carrying out a hydrolysis reaction, and adding a dispersion solvent during the condensation reaction, and agitating to gel the mixed solution during agitation and produce multiple hydrophilic or hydrophobic wet gel granules of aerogel. The overall preparation speed can be shortened quickly and at the same time the hydrophilic or hydrophobic wet gel granules of aerogel wet glue particles are prepared to increase the production efficiency of the wet gel granules of aerogel.

A preparation method of SiO.sub.2 aerogels is for solvent replacement process during preparation of SiO.sub.2 aerogels and adopts “a manner of continuously circulation filtration” for an operation of adding solvent so that wet gel is continuously circulated and replaced (rinsing) by mass alcohol solvent and organic solvent to greatly accelerate (reducing) the time for replacement operation of wet gel solvent. At the same time, the alcohol solvent or the organic solvent passing through the reaction container separates wet gel from water content or the alcohol solution through filtration procedure. Afterward the alcohol solution and the organic solution enter the reaction container to perform solvent replacement such that fast continuously circulation filtration is performed to greatly improve the effect of replacing wet gel solvent.

A system and method for producing an aerogel composite material includes a reaction vessel having a movable carrier basket for receiving a plurality of fiber mats, and a plurality of plates to space the fiber mats apart from one another. Once the plates have been removed, there are gaps between the aerogel insulating boards, through which hot drying air can be blown during a drying process. The method has the advantage that the quantities of solvents and reagents to be disposed of are minimal, and in addition thereto, no complex work-up processes are necessary.

A thermal insulation sheet is used that includes a fiber, a silica aerogel contained in the fiber, and a fibrous cavity. A method for manufacturing a thermal insulation sheet is used that includes: an impregnation step of impregnating a silica aerosol in a nonwoven fabric substrate containing a fiber that is insoluble in an acidic solution, and a fiber that is soluble in the acidic solution; a gelling step of gelling the silica aerosol; a hydrophobizing step of hydrophobizing the gel; and a drying step of drying the gel. The fiber that is soluble in the acidic solution is dissolved in the hydrophobizing step.

A thermal insulation sheet is used that includes a fiber, a silica aerogel contained in the fiber, and a fibrous cavity. A method for manufacturing a thermal insulation sheet is used that includes: an impregnation step of impregnating a silica aerosol in a nonwoven fabric substrate containing a fiber that is insoluble in an acidic solution, and a fiber that is soluble in the acidic solution; a gelling step of gelling the silica aerosol; a hydrophobizing step of hydrophobizing the gel; and a drying step of drying the gel. The fiber that is soluble in the acidic solution is dissolved in the hydrophobizing step.