Aerogel composition for battery heat insulating sheet, manufacturing method thereof, battery heat insulating sheet formed using the same, and manufacturing method thereof

Abstract

To provide an aerogel composition for a battery insulation sheet, a method of preparing the same, a battery insulation sheet formed using the same, and a manufacturing method thereof.SOLUTION: The present invention relates to an aerogel composition for a battery insulation sheet, a method of preparing the same, a battery insulation sheet formed using the same, and a manufacturing method thereof. The aerogel composition for a battery insulation sheet includes a solvent, a fibrous support, an aerogel, and a functional material including a binder, a dispersant, or a combination thereof. With respect to a total solid content of the aerogel composition, the fibrous support is present in a content range of 5 wt.% to 70 wt.%, the aerogel is present in a content range of 10 wt.% to 90 wt.%, and the functional material is present in a content range of 0.5 wt.% to 20 wt.%.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an aerogel composition for a battery heat insulating sheet, a method for producing the same, a battery heat insulating sheet formed using the same, and a method for producing the same. [Background technology]

[0002] Secondary batteries are power storage systems that offer excellent energy density by converting electrical energy into chemical energy and storing it. Unlike primary batteries, which cannot be recharged, secondary batteries are rechargeable and are widely used in IT devices such as smartphones, cellular phones, laptops, and tablet PCs. Recently, interest in electric vehicles has increased to prevent environmental pollution, leading to the adoption of high-capacity secondary batteries for electric vehicles. These secondary batteries are required to have characteristics such as high density, high output, and stability.

[0003] Furthermore, when a battery contains a large number of high-capacity cells such as lithium-ion secondary batteries, there is a risk that one cell may overheat for some reason and go into thermal runaway, adversely affecting other adjacent cells, so it is necessary to thermally insulate adjacent cells from each other.

[0004] For this reason, conventionally, plates or insulating resin plates have been placed between the cells to insulate and heat the adjacent cells.

[0005] The above information disclosed in the Background of the Invention section is intended solely to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art. Summary of the Invention [Problem to be solved by the invention]

[0006] One embodiment provides an aerogel composition having excellent heat insulation properties, durability, and low dust properties, a manufacturing method thereof, a battery insulation sheet formed using the aerogel composition, and a manufacturing method thereof. [Means for solving the problem]

[0007] One embodiment provides an aerogel composition comprising: a solvent; a fibrous support; an aerogel; and a functional material including a binder, a dispersant, or a combination thereof; wherein the fibrous support is contained in an amount of 5 wt% to 70 wt%, the aerogel is contained in an amount of 10 wt% to 90 wt%, and the functional material is contained in an amount of 0.5 wt% to 20 wt%, based on the total solid content of the aerogel composition.

[0008] The solvent may include one or more selected from the group consisting of polar solvents and non-polar solvents.

[0009] The weight ratio of the solvent to the total solid content of the aerogel composition may be 1:1 to 1:90.

[0010] The fibrous support may contain one or more fibers selected from the group consisting of natural fibers, silica fibers, glass fibers, carbon fibers, basalt fibers, and polymer fibers.

[0011] The aerogel has a BET specific surface area of ​​500 m 2 / g~1,000m 2 / g.

[0012] The binder includes an aqueous polymer binder, and the aqueous polymer binder may include one or more selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

[0013] The binder may be contained in an amount of 0.5% by weight to 20% by weight based on the total solid content of the aerogel composition.

[0014] The binder may include a water-soluble polymer and a water-dispersible polymer, and the water-soluble polymer and the water-dispersible polymer may be included in a weight ratio of 1:1 to 1:5.

[0015] The dispersant may include one or more selected from the group consisting of surfactants and phosphate salts.

[0016] The dispersant may be contained in an amount of 0.1% by weight to 6% by weight based on the total solid content of the aerogel composition.

[0017] The binder and the dispersant may be contained in a weight ratio of 1:0.001 to 1:0.67.

[0018] The aerogel composition may contain 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, and 2% by weight to 15% by weight of the binder, based on the total solid content of the aerogel composition.

[0019] The aerogel composition may contain 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, 2% by weight to 15% by weight of the binder, and 0.1% by weight to 5% by weight of the dispersant, relative to the total solid content of the aerogel composition.

[0020] Another embodiment provides a method for producing an aerogel composition, the method comprising the steps of: mixing a functional material, including a binder, a dispersant, or a combination thereof, with a solvent to prepare a solvent mixture; mixing the solvent mixture with an aerogel to prepare an aerogel mixture; and mixing the aerogel mixture with a fibrous support to prepare an aerogel composition, wherein the aerogel composition contains 5 wt % to 70 wt % of the fibrous support, 10 wt % to 90 wt % of the aerogel, and 0.5 wt % to 20 wt % of the functional material, based on the total solid content of the aerogel composition.

[0021] Yet another embodiment provides a battery insulation sheet including a substrate and an aerogel layer formed on the substrate, the aerogel layer being formed using the aerogel composition.

[0022] In yet another embodiment, there is provided a method for manufacturing a battery insulation sheet, the method including: coating the aerogel composition on a substrate; and drying the aerogel composition coated on the substrate.

[0023] In the step of drying the aerogel composition coated on the substrate, the drying temperature may be 25°C to 100°C. [Effects of the Invention]

[0024] A battery insulation sheet made from an aerogel composition according to an embodiment has excellent insulation properties and durability, has low manufacturing costs, and can prevent aerogel dust generation during manufacturing and actual use. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic diagram showing a battery insulation sheet formed between a plurality of cells according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating the structure of a battery insulation sheet according to an embodiment. [Figure 3] FIG. 3 is a schematic diagram illustrating the structure of a battery insulation sheet according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0026] Although the present invention will be described in detail below so that those skilled in the art can easily implement the present invention, it should be understood that the present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

[0027] Insulation is a material used to prevent the movement of heat from high to low places, and is used not only in the construction of refrigerators, cold storage warehouses, and buildings, but also in various industrial fields including the aircraft, electronic parts, and automotive industries.

[0028] Such a heat insulating material must have excellent heat insulating properties through low thermal conductivity, and also must have sufficient mechanical strength to maintain such heat insulating properties.

[0029] Aerogel is a transparent or translucent cutting-edge material with a nanoporous structure. It has very low density and low thermal conductivity, so it has great potential as an insulating material and is considered to be a highly efficient super-insulating material that can be used in a variety of industrial fields.

[0030] The greatest advantage of aerogel is that it has lower thermal conductivity than conventional organic insulation materials such as styrofoam, and it solves the fatal weaknesses of organic insulation materials, such as vulnerability to fire and the generation of harmful gases during a fire.

[0031] However, aerogels are generally very weak, being easily broken even by a small impact due to their high brittleness, and are difficult to process into very thin thicknesses and shapes. Therefore, despite their excellent thermal insulation properties, it is very difficult to manufacture thermal insulation materials using aerogels alone.

[0032] According to one embodiment, the aerogel composition may include a solvent; a fibrous support; an aerogel; and a functional material including a binder, a dispersant, or a combination thereof. The fibrous support may be present in an amount of 5 wt % to 70 wt %, the aerogel in an amount of 10 wt % to 90 wt %, and the functional material in an amount of 0.5 wt % to 20 wt %, based on the total solid content of the aerogel composition.

[0033] The battery insulation sheet made from the aerogel composition comprising the above components has excellent insulation properties and durability, requires low manufacturing costs, and prevents the generation of aerogel dust during manufacturing and actual use.

[0034] In one embodiment, the solvent may include at least one selected from the group consisting of polar solvents and non-polar solvents.

[0035] The polar solvent may include water, an alcohol-based solvent, or a combination thereof.

[0036] The water may include, for example, purified water, deionized water, or a combination thereof.

[0037] The alcohol-based solvent may include, but is not limited to, one or more selected from the group consisting of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol, and glycerol.

[0038] The non-polar solvent may include a hydrocarbon solvent, for example, one or more selected from the group consisting of hexane, pentane, heptane, toluene, and benzene, and more preferably, an alkane solvent such as hexane or a mixture containing an alkane solvent, but is not limited thereto.

[0039] The solvent may include water. Using water as a solvent can effectively reduce raw material costs and post-processing costs. However, when water is used as a solvent, it can be difficult to mix with hydrophobic aerogel. In one embodiment, however, the aerogel is uniformly dispersed by controlling the design of the mixing step, mixing conditions, and the addition and amounts of binder and dispersant. When the aerogel is uniformly dispersed in the composition, a thin battery insulation sheet with excellent insulation properties, durability, and low dust can be formed without using a large amount of binder.

[0040] The solvent may be contained in such a way that the weight ratio of the solvent to the total solid content of the aerogel composition is 1:1 to 1:90. For example, the weight ratio of the solvent to the total solid content of the aerogel composition may be 1:50 to 1:70, 1:20 to 1:30, or 1:2 to 1:10. By controlling the weight ratio of the solvent to the total solid content within the above range, the viscosity can be controlled and the aerogel layer can be coated.

[0041] In one embodiment, the fibrous support may be included in the aerogel composition to improve the durability of a battery insulation sheet formed using the aerogel composition.

[0042] The fibrous support may include fibers used in typical insulating material supports. For example, the fibrous support may include one or more fibers selected from the group consisting of natural fibers, silica fibers, glass fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers. Specific examples of the fibrous support include, but are not limited to, glass fibers.

[0043] The natural fibers may include, for example, one or more selected from the group consisting of hemp, jute, flax, coir, kenaf, and cellulose.

[0044] The mineral fibers may be, for example, mineral fibers containing one or more selected from the group consisting of basalt, wollastonite, alumina, silica, slag, and rock.

[0045] The polymer fiber may include, for example, one or more selected from the group consisting of nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamideimide, polyethyleneterephtalate, polybutyleneterephtalate, polyester, polyethylene (PE), and polypropylene (PP). Specific examples of the polymer fiber include, but are not limited to, any one or more of polyimide, polyamide, and polybenzimidazole.

[0046] The fibrous support may be, for example, in the form of wool or chopped strands, but is not limited thereto.

[0047] The length of the fibrous support may be, for example, 50 μm to 1000 μm, 70 μm to 800 μm, or 100 μm to 600 μm. By including a fibrous support having a length within the above range, the aerogel layer can be formed firmly and durability can be improved.

[0048] The diameter of the fibrous support may be, for example, 0.1 μm to 20 μm, 0.1 μm to 15 μm, 0.1 μm to 5 μm, 1 μm to 15 μm, or 3 μm to 10 μm. By including a fibrous support having a diameter within this range, the structure of the aerogel layer can be made more robust and production costs can be reduced.

[0049] The content of the fibrous support may be 5 to 70% by weight, 25 to 60% by weight, or 30 to 50% by weight, based on the total solid content of the aerogel composition. When a battery insulation sheet is produced using an aerogel composition containing a fibrous support within the above range, the durability of the battery insulation sheet can be improved.

[0050] In one embodiment, the aerogel has a BET specific surface area of ​​500 m 2 / g~1,000m 2 For example, the aerogel may have a BET specific surface area of ​​500 m 2 / g~950m 2 / g, 550m 2 / g~950m 2 / g or 600m 2 / g~900m 2 By including an aerogel having a BET specific surface area within the above range, it is possible to provide a heat insulating sheet that can effectively prevent heat transfer and heat propagation between a plurality of cells.

[0051] The particle size of the aerogel may be 5 μm to 200 μm, 10 μm to 100 μm, or 20 μm to 50 μm. By including aerogel having a particle size within the above range, the heat insulating properties can be improved and heat transfer between multiple cells can be delayed.

[0052] The content of the aerogel may be 10 to 90 wt %, 30 to 70 wt %, or 40 to 60 wt % based on the total solid content of the aerogel composition. When a battery insulation sheet is produced using an aerogel composition containing aerogel in this range, the heat insulating properties of the battery insulation sheet can be improved.

[0053] In one embodiment, the binder may include a water-based polymer binder, for example, the water-based polymer binder may include at least one selected from the group consisting of a water-soluble polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

[0054] The aqueous polymer may include, but is not limited to, one or more selected from the group consisting of polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinylpyrrolidone.

[0055] The anionic water-soluble polymer may include one or more polymers having functional groups such as carboxylic acid, sulfonic acid, sulfate, phosphate, and salts thereof. For example, the anionic water-soluble polymer may be a polymer having a carboxylic acid group, and may include, but is not limited to, polymaleic acid.

[0056] The cationic water-soluble polymer may include one or more selected from the group consisting of polymers having functional groups such as amine, ammonium, phosphonium, sulfonium, and salts thereof. For example, the cationic water-soluble polymer may be a polymer having an amine group, and specific examples thereof may include, but are not limited to, one or more selected from the group consisting of polyethylene amine and polyamine.

[0057] The water-dispersible polymer may include, but is not limited to, one or more selected from the group consisting of water-dispersible polyurethane and water-dispersible polyester.

[0058] The binder may include a water-soluble polymer and a water-dispersible polymer. For example, the binder may include a water-soluble polymer having binder and dispersing properties and a water-dispersible polyurethane having fire-resistant properties, or specifically, a polyvinyl alcohol and a water-dispersible polyurethane.

[0059] The weight ratio of the aqueous polymer to the water-dispersible polymer may be 1:1 to 1:5, 1:1 to 1:4, or 1:2 to 1:3. When the aqueous polymer and the water-dispersible polymer are mixed and used in a weight ratio within this range, the heat insulation properties, dust resistance, and compressibility of the heat insulating sheet can be further improved, as well as the fire resistance and mechanical properties.

[0060] The content of the binder may be 0.5 to 20 wt %, 2 to 15 wt %, or 8 to 15 wt % based on the total solid content of the aerogel composition. When a battery insulation sheet is produced using an aerogel composition containing a binder within this range, the dust resistance of the battery insulation sheet can be improved.

[0061] In one embodiment, the dispersant may include at least one selected from the group consisting of surfactants and phosphate salts, including, but not limited to, nonionic surfactants, anionic surfactants, amphoteric surfactants, natural surfactants such as lecithin, and phosphate salts.

[0062] When the dispersant is further contained, the dispersion of the aerogel in the composition is further improved, and the fibrous support and the aerogel can be uniformly dispersed.

[0063] The content of the dispersant may be 0.1 to 6 wt %, 0.1 to 5 wt %, or 0.1 to 3 wt %, based on the total solid content of the aerogel composition. When the dispersant is contained within the above range, the aerogel composition can be produced inexpensively, and a battery insulation sheet having excellent heat insulation properties, durability, and dust resistance can be produced using the aerogel composition.

[0064] In one embodiment, the binder and the dispersant may be included in a weight ratio of 1:0.001 to 1:0.67, 1:0.001 to 1:0.5, or 1:0.001 to 1:0.3. When the binder and the dispersant are mixed in a weight ratio within this range, the aerogel may be more uniformly dispersed in the aerogel layer.

[0065] In one embodiment, the aerogel composition may contain 25 wt % to 60 wt % of the fibrous support, 30 wt % to 70 wt % of the aerogel, and 2 wt % to 15 wt % of the binder, based on the total solid content of the aerogel composition.

[0066] As a specific example, the aerogel composition may contain 30 to 50% by weight of the fibrous support, 40 to 60% by weight of the aerogel, and 8 to 15% by weight of the binder, based on the total solid content of the aerogel composition. When the aerogel composition is formed within these ranges, it is possible to realize excellent heat insulation properties and improve durability, and to improve the bonding strength between the fibrous support and the aerogel, thereby preventing dust generation.

[0067] In one embodiment, the aerogel composition may contain 25 wt % to 60 wt % of the fibrous support, 30 wt % to 70 wt % of the aerogel, 2 wt % to 15 wt % of the binder, and 0.1 wt % to 5 wt % of the dispersant, based on the total solid content of the aerogel composition.

[0068] As a specific example, the aerogel composition may contain 30% to 50% by weight of the fibrous support, 40% to 60% by weight of the aerogel, 5% to 10% by weight of the binder, and 0.1% to 3% by weight of the dispersant, relative to the total solid content of the aerogel composition. When the aerogel composition is formed within these ranges, the dispersibility of the aerogel can be improved, excellent heat insulation can be realized, and durability can be improved. The bonding strength between the fibrous support and the aerogel can be improved, preventing dust generation.

[0069] In one embodiment, the aerogel composition may further include a silane-based compound. The silane-based compound may include at least one selected from the group consisting of 3-(trimethoxysilyl)propylmethacrylate, methyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octadecyltrimethoxysilane, ethyltriethoxysilane, and 3-glycidoxypropyltrimethoxysilane. When the silane-based compound is further included, dispersibility can be further improved.

[0070] In one embodiment, additives such as wetting agents, emulsifiers, compatibilizers, viscosity modifiers, pH adjusters, stabilizers, antioxidants, acid or base scavengers, metal deactivators, antifoaming agents, antistatic agents, thickeners, adhesion improvers, binders, flame retardants, impact modifiers, pigments, dyes, colorants, and deodorizers may be optionally included.

[0071] According to one embodiment, a method for producing an aerogel composition includes the steps of: mixing a functional material, including a binder, a dispersant, or a combination thereof, with a solvent to produce a solvent mixture; mixing the solvent mixture with an aerogel to produce an aerogel mixture; and mixing the aerogel mixture with a fibrous support to produce an aerogel composition, wherein the aerogel composition may contain 5 wt % to 70 wt % of the fibrous support, 10 wt % to 90 wt % of the aerogel, and 0.5 wt % to 20 wt % of the functional material, based on a total solid content of the aerogel composition.

[0072] In the step of preparing the solvent mixture by mixing the functional material with the solvent, a binder may be mixed with the solvent, or a binder and a dispersant may be mixed with the solvent, as described above.

[0073] In the step of preparing the aerogel mixture by mixing the solvent mixture with the aerogel, the aerogel may be added in a powder form, and the specific description of the aerogel is as described above.

[0074] In the step of preparing an aerogel composition by mixing the aerogel mixture with the fibrous support, the specific description of the fibrous support is as described above.

[0075] In each of the steps of mixing the solvent with a functional material, such as a binder, a dispersant, or a combination thereof, to prepare a solvent mixture, mixing the solvent mixture with an aerogel to prepare an aerogel mixture, and mixing the aerogel mixture with a fibrous support to prepare an aerogel composition, a mixer may be used during mixing. For example, the mixer may include, but is not limited to, a planetary mixer or a thinky mixer.

[0076] For example, a planetary mixer can be used to mix the solvent mixture with the aerogel. When the planetary mixer is used to mix the solvent mixture with the aerogel, the aerogel can be uniformly dispersed in the solvent.

[0077] The planetary mixer may be a device that can be used to mix or agitate other materials to produce a homogeneous mixture. It may include blades capable of planetary motion.

[0078] In one embodiment, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades. For example, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades.

[0079] The planetary blades and high-speed dispersion blades rotate continuously about their axes, and the rotational speed can be expressed in units of rotations per minute (rpm).

[0080] In one embodiment, the planetary mixer may include a first blade and a second blade having different rotation axes. For example, the first blade may be a low-speed blade and the second blade may be a high-speed blade. Here, low speed and high speed refer to the relative rotation speeds between the first blade and the second blade. For example, the first blade may be an open blade and the second blade may be a Despa blade.

[0081] The rotation speed of the first blade may be, for example, 10 rpm to 100 rpm, 10 rpm to 60 rpm, or 30 rpm to 70 rpm, and the rotation speed of the second blade may be, for example, 100 rpm to 2000 rpm, 100 rpm to 1000 rpm, 300 rpm to 1700 rpm, or 500 rpm to 1700 rpm.

[0082] When the functional material is mixed with the solvent, the rotation speed of the first blade of the mixer may be 10 to 60 rpm, 20 to 50 rpm, or 30 to 40 rpm, and the rotation speed of the second blade may be 300 to 1700 rpm, 600 to 1000 rpm, or 700 to 800 rpm. When the solvent and functional material are mixed as described above, a solvent mixture in which the binder, dispersant, or a combination thereof is uniformly dispersed is prepared, which makes it easier to mix the aerogel in the subsequent step.

[0083] When mixing the solvent mixture with the aerogel, the rotation speed of the first blade of the mixer may be 30 rpm to 70 rpm, 40 rpm to 70 rpm, or 60 rpm to 70 rpm, and the rotation speed of the second blade may be 500 rpm to 1700 rpm, 600 rpm to 1600 rpm, or 800 rpm to 1500 rpm. When the aerogel is added to the solvent mixture and mixed as described above, it is possible to prevent the aerogel from agglomerating with each other and induce uniform dispersion.

[0084] When mixing the aerogel mixture with the fibrous support, the rotation speed of the first blade of the mixer may be 10 rpm to 60 rpm, 20 rpm to 50 rpm, or 30 rpm to 40 rpm, and the rotation speed of the second blade may be 300 rpm to 1700 rpm, 400 rpm to 1500 rpm, or 800 rpm to 1200 rpm. When mixing the aerogel mixture with the fibrous support as described above, air bubbles within the composition are removed, the viscosity is adjusted, and the fibrous support is easily dispersed among the uniformly dispersed aerogel. The aerogel may even be present in a form in which it surrounds the fibrous support within the composition. Here, a binder may be present between the aerogel and the fibrous support, which can improve the bonding strength between the aerogel and the fibrous support.

[0085] FIG. 1 is a schematic diagram showing a battery insulation sheet formed between a plurality of cells according to an embodiment.

[0086] 1, a battery insulation sheet 100 according to an embodiment may be formed between each of the cells 200 in a battery module including the plurality of cells 200. Here, the upper and lower surfaces of the battery insulation sheet may be disposed to face each of the adjacent cells. By forming the battery insulation sheet 100 according to an embodiment between each of the plurality of cells 200, a fire can be blocked in advance within the cell and the spread of the fire to other cells can be minimized, thereby providing a battery module and a battery pack including the same with improved safety.

[0087] FIG. 2 is a schematic diagram illustrating the structure of a battery insulation sheet according to an embodiment.

[0088] Referring to FIG. 2, the battery insulation sheet 100 includes a substrate 110 and an aerogel layer 120 formed on the substrate 110, where the upper and lower surfaces of the battery insulation sheet may be arranged to face the adjacent cells, respectively.

[0089] By forming an aerogel layer using the aerogel composition according to an embodiment on the substrate, the battery insulation sheet has improved heat insulation properties and durability, and can prevent the aerogel from detaching and generating dust when the battery insulation sheet is manufactured or installed inside a device.

[0090] The specific description of the aerogel composition forming the aerogel layer in the battery insulation sheet is as described above.

[0091] The substrate may be of any type, including, for example, a resin, a metal, an inorganic material other than a metal, or a composite thereof, and the substrate may be in any form, including, but not limited to, a film, a thin film, a sheet, or the like.

[0092] The resin may include, for example, one or more selected from the group consisting of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0093] The metal may include, for example, one or more selected from the group consisting of copper, nickel, cobalt, iron, chromium, vanadium, palladium, ruthenium, rhodium, molybdenum, tungsten, iridium, silver, gold, and platinum. When using a substrate made of a metal material, the substrate may be subjected to corrosion prevention treatment, insulation treatment, etc., as necessary.

[0094] The inorganic material may include one or more selected from the group consisting of calcium carbonate (CaCO3), talc, and mica.

[0095] As a specific example, the substrate may include an inorganic material, and as a further specific example, it may include mica, which can improve the heat insulating properties and durability of the heat insulating sheet.

[0096] In one embodiment, the aerogel layer may be formed as a single layer or a multi-layer structure. When the aerogel layer is formed as a multi-layer structure, the aerogel layer may be formed as 2 to 10 layers, 2 to 7 layers, or 2 to 5 layers.

[0097] FIG. 3 is a schematic diagram showing the structure of a battery insulation sheet according to another embodiment.

[0098] 3, in one embodiment, the battery insulation sheet 100 may have a structure including a first substrate 130, an aerogel layer 120 formed on the first substrate 130, and a second substrate 140 formed on the aerogel layer 120. Here, the first substrate and the second substrate may be disposed to face the adjacent cell, respectively. In this case, the first substrate and the second substrate may be formed of the same or different materials.

[0099] A method for manufacturing a battery insulation sheet according to an embodiment may include coating the aerogel composition on a substrate, and drying the aerogel composition coated on the substrate, where the substrate may refer to the substrate of FIG. 2 or one of the first and second substrates of FIG. 3.

[0100] In the method for manufacturing the battery insulation sheet, the specific description of the substrate and the aerogel composition is as described above.

[0101] The coating step may be performed by applying an aerogel slurry onto a conventional substrate.

[0102] The coating step may be repeated once or more than once.

[0103] The drying step may be performed at a temperature of, for example, 25° C. to 100° C., 45° C. to 90° C., or 60° C. to 85° C. Drying under these temperature conditions may prevent detachment between the substrate and the aerogel layer, and a robust aerogel layer may be formed on the substrate without the use of a separate adhesive or bonding material, and a coating layer may be formed in which the aerogel coats the peripheries of a plurality of dispersed fibrous supports.

[0104] In one embodiment, the method for manufacturing a battery insulation sheet may further include laminating a substrate on the coated aerogel composition before drying. In this case, a battery insulation sheet may be manufactured having a structure in which multiple substrates, for example, a first substrate and a second substrate, are formed on both sides of the aerogel layer without an adhesive layer.

[0105] According to an embodiment, a battery insulation sheet can be manufactured using a simple method of coating a substrate with an aerogel composition and drying it, without using a separate adhesive or forming an adhesive layer. The aerogel is uniformly dispersed, achieving excellent insulation properties, durability, and low dust even at a thin thickness.

[0106] Specific examples of the present invention will be presented below. However, the examples described below are merely for the purpose of specifically illustrating and explaining the present invention, and the present invention is not limited thereto. Furthermore, since the contents not described here can be sufficiently inferred by those skilled in the art, the description thereof will be omitted.

[0107] (Manufacture of battery insulation sheets) Example 1 1. Preparation of Aerogel Composition Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) was added as a binder to ultrapure water as a solvent, and mixed under conditions of an open blade of 30 rpm and a despa blade of 700 rpm to produce a solvent mixture. 2 An aerogel mixture was prepared by adding 1 / g of aerogel and mixing with an open blade at 70 rpm and a Despa blade at 1500 rpm. Glass wool was added to the aerogel mixture and mixing with an open blade at 30 rpm and a Despa blade at 1200 rpm to prepare an aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0108] The solid content of the prepared aerogel composition was confirmed to be 50 wt % aerogel, 40 wt % glass wool, and 10 wt % polyvinyl alcohol.

[0109] 2. Battery insulation sheet manufacturing The prepared aerogel composition was applied as a slurry onto a 0.1 mm thick mica sheet (Famica, Muscovite), and then another 0.1 mm thick mica sheet was sandwiched between them and rolled to form a coating. The aerogel layer was then formed by drying at 60°C for 24 hours, producing a battery insulation sheet. The total thickness of the battery insulation sheet was measured to be 1.38 mm.

[0110] Example 2 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added were adjusted to prepare an aerogel composition having a solid content of 60 wt % aerogel, 25 wt % glass wool, and 15 wt % polyvinyl alcohol.

[0111] Example 3 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added were adjusted to prepare an aerogel composition having a solid content of 65 wt % aerogel, 25 wt % glass wool, and 10 wt % polyvinyl alcohol.

[0112] Example 4 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added were adjusted to prepare an aerogel composition having a solid content of 45 wt % aerogel, 50 wt % glass wool, and 5 wt % polyvinyl alcohol.

[0113] Example 5 The aerogel composition was prepared in the same manner as in Example 1, except that water-dispersible polyurethane was used as the binder instead of polyvinyl alcohol.

[0114] Example 6 1. Preparation of Aerogel Composition Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder and surfactant (Triton-X100, Sigma Aldrich) as a dispersant were added to the ultrapure water solvent, and mixed at an open blade speed of 30 rpm and a desparate blade speed of 700 rpm to produce a solvent mixture. 2An aerogel mixture was prepared by adding 1 / g of aerogel and mixing with an open blade at 70 rpm and a Despa blade at 1500 rpm. Glass wool was added to the aerogel mixture and mixing with an open blade at 30 rpm and a Despa blade at 1200 rpm to prepare an aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0115] The solid content of the prepared aerogel composition was confirmed to be 50 wt % aerogel, 40 wt % glass wool, 9.9 wt % polyvinyl alcohol, and 0.1 wt % dispersant.

[0116] 2. Battery insulation sheet manufacturing The prepared aerogel composition was applied as a slurry onto a 0.1 mm thick mica sheet (Famica, Muscovite), and then another 0.1 mm thick mica sheet was sandwiched and rolled to form a coating. The aerogel layer was then formed by drying at 60°C for 24 hours, producing a battery insulation sheet. The total thickness of the battery insulation sheet was confirmed to be 1.38 mm.

[0117] Example 7 1. Preparation of Aerogel Composition Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder, water-dispersible polyurethane, and surfactant (Triton-X100, Sigma Aldrich) as a dispersant were added to ultrapure water as a solvent, and mixed with an open blade at 30 rpm and a despa blade at 700 rpm to prepare a solvent mixture. 2 An aerogel mixture was prepared by adding 1 / g of aerogel and mixing with an open blade at 70 rpm and a Despa blade at 1500 rpm. Glass wool was added to the aerogel mixture and mixing with an open blade at 30 rpm and a Despa blade at 1200 rpm to prepare an aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0118] The solid content of the prepared aerogel composition was confirmed to be 50 wt % aerogel, 40 wt % glass wool, 3 wt % polyvinyl alcohol, 6.9 wt % water-dispersible polyurethane, and 0.1 wt % dispersant.

[0119] 2. Battery insulation sheet manufacturing The prepared aerogel composition was applied as a slurry onto a 0.1 mm thick mica sheet (Famica, Muscovite), and then another 0.1 mm thick mica sheet was sandwiched and rolled to form a coating. The aerogel layer was then formed by drying at 60°C for 24 hours, producing a battery insulation sheet. The total thickness of the battery insulation sheet was confirmed to be 1.38 mm.

[0120] Comparative Example 1 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added were adjusted to prepare an aerogel composition with a solid content of 50 wt % aerogel, 49.7 wt % glass wool, and 0.3 wt % polyvinyl alcohol.

[0121] Comparative Example 2 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added were adjusted to prepare an aerogel composition having a solid content of 40 wt % aerogel, 35 wt % glass wool, and 25 wt % polyvinyl alcohol.

[0122] (Experimental example) Experimental example 1: Evaluation of thermal insulation The heat insulating properties were evaluated using the heat insulating sheets produced in Examples 1 to 7 and Comparative Examples 1 and 2.

[0123] Specifically, each heat insulating sheet was inserted between a pair of opposing 1 mm thick aluminum plates, which were then placed on a heat press. The upper plate of the heat press was heated to 350°C, while the lower plate of the heat press was not heated and maintained at an initial temperature of 40°C. A pressure of 20 kN was then applied to the lower plate of the heat press, and the temperature of the lower plate of the heat press was measured after 11 minutes. The results are shown in Table 1 below.

[0124] Experimental example 2: Dust evaluation The heat insulating sheets manufactured in Examples 1 to 7 and Comparative Examples 1 and 2 were used to evaluate dustiness.

[0125] Specifically, the weight of each insulation sheet was measured before the evaluation. Then, the insulation sheet was placed on a rubber plate and hit with a rubber hammer at five points (tops and center) to remove dust, and then the weight of the insulation sheet was measured. The weight before and after the physical impact was compared to calculate the weight loss rate, and the results are shown in Table 1 below.

[0126] [Table 1]

[0127] Referring to Table 1, it was confirmed that Examples 1 to 7 had excellent insulation properties and dust resistance. Looking at Examples 1 to 4, it was confirmed that the insulation properties and dust resistance varied depending on the component content of the aerogel composition. Furthermore, in Example 5, dust resistance was slightly reduced because the fire-resistant binder was unable to function as a dispersant, but insulation properties were improved. Looking at Example 6, it was confirmed that the insulation properties and dust resistance were further improved when a binder and a dispersant were mixed. Looking at Example 7, it was confirmed that the insulation properties and dust resistance were further improved when polyvinyl alcohol and a water-dispersible polyurethane binder were mixed.

[0128] In addition, it was confirmed that the compressibility and dust resistance were reduced by controlling the component contents of the aerogel composition in Comparative Example 1. In addition, it was confirmed that the heat insulating properties and compressibility were significantly reduced in Comparative Example 2 due to the low aerogel content and the high contents of the fibrous support and binder.

[0129] Therefore, it was confirmed that the aerogel composition according to an embodiment has excellent heat insulation properties, durability, and low dust generation properties.

[0130] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications are possible within the scope of the claims, the detailed description of the invention, and the accompanying drawings, and it goes without saying that these modifications also fall within the scope of the present invention. [Explanation of symbols]

[0131] 100 Battery Heat Insulation Sheet 110 Base material 120 aerogel layer 130 First base material 140 Second base material 200 cells

Claims

1. a solvent; A fibrous support; Aerogel and a functional material comprising a binder or a combination of a binder and a dispersant; the aerogel composition contains, relative to the total solid content, 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, 2% by weight to 20% by weight of the functional material, and 2% by weight to 15% by weight of the binder; the binder comprises a water-based polymer binder; the aqueous polymer binder comprises a water-based polymer and a water-dispersible polymer; The aerogel composition for a battery insulation sheet, wherein the aqueous polymer and the water-dispersible polymer are contained in a weight ratio of 1:1 to 1:

5.

2. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the solvent comprises at least one selected from the group consisting of polar solvents and non-polar solvents.

3. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein a weight ratio of the solvent to the total solid content of the aerogel composition is 1:1 to 1:

90.

4. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the fibrous support comprises at least one fiber selected from the group consisting of natural fiber, silica fiber, glass fiber, carbon fiber, basalt fiber, and polymer fiber.

5. The aerogel has a BET specific surface area of ​​500 m ２ / g to 1,000m ２ 2. The aerogel composition for a battery insulating sheet according to claim 1, wherein the aerogel composition has a viscosity of 1000 MPa or less.

6. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the binder is contained in an amount of 0.5 wt % to 20 wt % based on the total solid content of the aerogel composition.

7. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the dispersant comprises at least one selected from the group consisting of a surfactant and a phosphate salt.

8. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the dispersant is contained in an amount of 0.1 wt % to 6 wt % based on the total solid content of the aerogel composition.

9. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the binder and the dispersant are contained in a weight ratio of 1:0.001 to 1:0.

67.

10. 2. The aerogel composition for a battery insulation sheet according to claim 1, comprising, relative to a total solid content of the aerogel composition, 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, 2% by weight to 15% by weight of the binder, and 0.1% by weight to 5% by weight of the dispersant.

11. mixing a functional material including a binder or a combination of a binder and a dispersant with a solvent to prepare a solvent mixture; mixing the solvent mixture with an aerogel to prepare an aerogel mixture; mixing the aerogel mixture with a fibrous support to produce an aerogel composition; the aerogel composition contains, relative to the total solid content, 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, 2% by weight to 20% by weight of the functional material, and 2% by weight to 15% by weight of the binder; the binder comprises a water-based polymer binder; the aqueous polymer binder comprises a water-based polymer and a water-dispersible polymer; The method for producing an aerogel composition for a battery insulation sheet, wherein the aqueous polymer and the water-dispersible polymer are contained in a weight ratio of 1:1 to 1:

5.

12. A substrate; an aerogel layer formed on the substrate, The battery insulating sheet, wherein the aerogel layer is formed using the aerogel composition according to claim 1 .

13. Coating a substrate with the aerogel composition of any one of claims 1 to 10; and drying the aerogel composition coated on the substrate.

14. The method for manufacturing a heat insulating sheet according to claim 13, wherein the drying temperature in the step of drying the aerogel composition coated on the substrate is 25°C to 100°C.

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