Aerogel composition for battery insulation sheets, method for producing the same, battery insulation sheet formed using the same, and method for producing the same

Abstract

To provide an aerogel composition for a battery insulation sheet, a manufacturing method therefor, a battery insulation sheet formed therewith, and a manufacturing method therefor.SOLUTION: An aerogel composition for a battery insulation sheet, a manufacturing method therefor, a battery insulation sheet formed therewith, and a manufacturing method therefor are provided herein. The aerogel composition includes a solvent, a fibrous support, an aerogel, an antifoaming agent, and a functional material including a binder, a dispersant, or a combination thereof, wherein the fibrous support is 5 wt.% to 70 wt.%, the aerogel is 10 wt.% to 90 wt.%, the antifoaming agent is 0.05 wt.% to 2 wt.%, and the functional material is 0.5 wt.% to 20 wt.%, with respect to a total solid amount of the aerogel composition.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This invention relates to an aerogel composition for battery insulation sheets, a method for producing the same, a battery insulation sheet formed using the same, and a method for producing the same. [Background technology]

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

[0003] Furthermore, in the case of a large number of high-capacity cells, such as lithium-ion secondary batteries, there is a risk that one cell may overheat and undergo thermal runaway for some reason, adversely affecting the other adjacent cells. Therefore, thermal insulation between adjacent cells is required.

[0004] Conventionally, plates or insulating resin sheets were placed between cells to provide insulation and heat retention between adjacent cells.

[0005] The information disclosed above in the technology underlying such inventions is solely for the purpose of improving understanding of the background of the present invention, and therefore may include information that does not constitute prior art. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] One example provides an aerogel composition for battery insulation sheets having excellent heat insulation properties, low dust characteristics, and sheet uniformity, a method for producing the same, a battery insulation sheet formed using the same, and a method for producing the same. [Means for solving the problem]

[0007] One example provides an aerogel composition comprising a solvent; a fibrous support; an aerogel; an antifoaming agent; and a functional substance including a binder, a dispersant, or a combination thereof, wherein the fibrous support accounts for 5% to 70% by weight, the aerogel for 10% to 90% by weight, the antifoaming agent for 0.05% to 2% by weight, and the functional substance for 0.5% to 20% by weight, based on the total solid content of the aerogel composition.

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

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

[0010] The fibrous support may include 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 m². 2 / g~1,000m 2 / g is also acceptable.

[0012] The aforementioned defoaming agent may include a silicone-based defoaming agent.

[0013] The binder comprises an aqueous polymer binder, and the aqueous polymer binder may contain one or more selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

[0014] The binder may be present in an amount of 0.5% to 20% by weight relative to the total solid content of the aerogel composition.

[0015] The binder comprises an aqueous polymer and a water-dispersible polymer, which may be present in a weight ratio of 1:1 to 1:5.

[0016] The dispersant may contain one or more selected from the group consisting of surfactants and phosphate salts.

[0017] The dispersant may be present in an amount of 0.1% to 6% by weight relative to the total solid content of the aerogel composition.

[0018] The binder and the dispersant may be present in a weight ratio of 1:0.001 to 1:0.67.

[0019] The aerogel composition may contain, with respect to the total solid content, 25% to 60% by weight of the fibrous support, 30% to 70% by weight of the aerogel, 0.1% to 1% by weight of the defoaming agent, and 2% to 15% by weight of the binder.

[0020] The aerogel composition may contain, with respect to the total solid content, 25% to 60% by weight of the fibrous support, 30% to 70% by weight of the aerogel, 0.1% to 1% by weight of the defoaming agent, 2% to 15% by weight of the binder, and 0.1% to 5% by weight of the dispersant.

[0021] Another embodiment provides a method for producing an aerogel composition, comprising the steps of: mixing a functional substance containing 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; mixing the aerogel mixture with a fibrous support to produce an aerogel composition; and mixing the aerogel composition with an antifoaming agent; wherein the fibrous support is present in an amount of 5% to 70% by weight, the aerogel in an amount of 10% to 90% by weight, the antifoaming agent in an amount of 0.05% to 2% by weight, and the functional substance in an amount of 0.5% to 20% by weight, relative to the total solid content of the aerogel composition.

[0022] In the method for producing the aerogel composition, at each stage, mixing can be carried out using a mixer, and the mixer may include a low-speed first blade and a high-speed second blade. The rotational speed of the second blade in the stage of mixing the aerogel composition and the antifoaming agent may be 30% to 75% of the rotational speed of the second blade in any one or more of the stages of mixing the solvent mixture and the aerogel to produce an aerogel mixture, and mixing the aerogel mixture and the fibrous support to produce the aerogel composition.

[0023] Another embodiment includes a base material and an aerogel layer formed on the base material, and the aerogel layer provides a battery heat insulation sheet formed using the aerogel composition.

[0024] Yet another embodiment provides a method for manufacturing a battery heat insulation sheet, including a stage of coating the aerogel composition on a base material and a stage of drying the aerogel composition coated on the base material.

Advantages of the Invention

[0025] A battery heat insulation sheet manufactured with an aerogel composition according to one embodiment is excellent in heat insulation and uniformity, has low manufacturing process costs, and can prevent the generation of aerogel dust during the manufacturing process and actual use.

Brief Description of the Drawings

[0026] [Figure 1] FIG. 1 is a schematic diagram showing a battery heat insulation sheet according to one embodiment formed between a plurality of cells. [Figure 2] FIG. 2 is a schematic diagram showing the structure of a battery heat insulation sheet according to one embodiment. [Figure 3] FIG. 3 is a schematic diagram showing the structure of a battery heat insulation sheet according to one embodiment. [Figure 4] FIG. 4 is a diagram showing the evaluation criteria for the uniformity of a battery heat insulation sheet according to one embodiment. [Modes for carrying out the invention]

[0027] The following detailed descriptions of the implementation examples are intended to be easily implemented by those with ordinary technical knowledge. However, the implementation examples can be implemented in a variety of different forms and are not limited to those described herein.

[0028] Insulation materials are materials used to prevent the flow of heat from areas of high temperature to areas of low temperature. They are used not only in the construction of refrigerators, cold storage warehouses, and buildings, but also in various industrial fields, including the aerospace, electronics, and automotive industries.

[0029] Such insulation materials must possess excellent thermal insulation properties through low thermal conductivity, and also require mechanical strength to sustainably maintain this insulation performance.

[0030] Furthermore, aerogel is a transparent or translucent advanced material with a nanoporous structure. Due to its extremely low density and low thermal conductivity, it not only has high potential as an insulating material but is also highly regarded as a very efficient super-insulating material that can be used in a variety of industrial fields.

[0031] Furthermore, the greatest advantages of aerogel are its lower thermal conductivity compared to conventional organic insulation materials such as polystyrene foam, and its ability to solve the critical weaknesses of organic insulation materials: fire vulnerability and the generation of harmful gases during a fire.

[0032] However, generally speaking, aerogels have very low strength due to their high brittleness, making them easily torn even by small impacts, and they are difficult to process into very thin thicknesses and shapes. Therefore, despite their excellent thermal insulation properties, it has been extremely difficult to manufacture thermal insulation materials using aerogels alone.

[0033] An aerogel composition according to one embodiment comprises a solvent; a fibrous support; an aerogel; an antifoaming agent; and a functional substance including a binder, a dispersant, or a combination thereof, wherein the fibrous support may be present in an amount of 5% to 70% by weight, the aerogel in an amount of 10% to 90% by weight, the antifoaming agent in an amount of 0.05% to 2% by weight, and the functional substance in an amount of 0.5% to 20% by weight, relative to the total solid content of the aerogel composition.

[0034] A battery insulation sheet manufactured using the aerogel composition comprising the aforementioned components offers excellent heat insulation and durability, low manufacturing costs, and simultaneously prevents the generation of aerogel dust during the manufacturing process and actual use.

[0035] In one embodiment, the solvent may include a polar solvent, a nonpolar solvent, or a combination thereof.

[0036] The polar solvent may include water, an alcohol-based solvent, or a combination thereof.

[0037] The water may include, for example, purified water, ultrapure water (deionized water), or a combination thereof.

[0038] 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.

[0039] The nonpolar solvent may include a hydrocarbon solvent. For example, the hydrocarbon solvent may include one or more selected from the group consisting of hexane, pentane, heptane, toluene, and benzene, or more preferably an alkane solvent such as hexane or a mixture including an alkane solvent, but is not limited to these.

[0040] The solvent may include water. When water is used as the solvent, raw material costs and post-processing costs can be effectively reduced. However, when water is used as the solvent, there is a problem in that mixing with hydrophobic aerogel is not easy. In one example, the aerogel was uniformly dispersed by controlling the design of the mixing stage, mixing conditions, and the addition and amount of binder and dispersant. When the aerogel is uniformly dispersed in the composition in this way, a battery insulation sheet with excellent heat insulation, durability, and low dust characteristics can be formed at a thin thickness without using a large amount of binder.

[0041] The solvent may be included in such a weight ratio of 1:1 to 1:90 with respect to the total solid content of the aerogel composition. 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 this range, viscosity can be controlled and the aerogel layer can be coated.

[0042] In one embodiment, the fibrous support, by being included in the aerogel composition, can improve the durability of the battery insulation sheet formed using it.

[0043] The fibrous support may include fibers commonly used in supports for thermal insulation materials. 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. Specifically, the fibrous support may include, but is not limited to, glass fibers.

[0044] The aforementioned natural fibers may include, for example, one or more selected from the group consisting of hemp, jute, flax, koir, kenaf, and cellulose.

[0045] The mineral fiber may be, for example, a mineral fiber containing one or more selected from the group consisting of basalt, wollastonite, alumina, silica, slag, and rock.

[0046] The polymer fiber may include, for example, one or more selected from the group consisting of nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamideimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyethylene (PE), and polypropylene (PP). Specifically, the polymer fiber may include, but is not limited to, one or more selected from the group consisting of polyimide, polyamide, and polybenzimidazole.

[0047] The fibrous support may be, for example, in the form of wool or chopped strands, but is not limited to these.

[0048] 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, an aerogel layer can be firmly formed and the durability can be improved.

[0049] 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 the above range, the structure of the aerogel layer can be made firm and the manufacturing cost can be reduced.

[0050] The content of the fibrous support may be 5% by weight to 70% by weight, 25% by weight to 60% by weight or 30% by weight to 50% by weight based on the total solid content of the aerogel composition. When manufacturing a battery heat insulation sheet using an aerogel composition containing a fibrous support within the above range, the durability of the battery heat insulation sheet can be improved.

[0051] In one embodiment, the aerogel has a BET specific surface area of 500 m 2 / g to 1,000 m 2 / g. For example, the aerogel may have a BET specific surface area of 500 m 2 / g to 950 m 2 / g, 550 m 2 / g to 950 m 2 / g or 600 m 2 / g to 900 m 2 / g. By including an aerogel having a BET specific surface area value within the above range, a heat insulation sheet that can effectively prevent heat transfer and heat propagation between a plurality of cells can be provided.

[0052] 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 an aerogel having a particle size within the above range, the heat insulation characteristics can be improved and heat transfer between a plurality of cells can be delayed.

[0053] The aerogel content may be 10% to 90% by weight, 30% to 70% by weight, or 40% to 60% by weight, relative to the total solid content of the aerogel composition. When a battery insulation sheet is manufactured using an aerogel composition containing aerogel within the above range, the thermal insulation properties of the battery insulation sheet can be improved.

[0054] In one embodiment, the defoaming agent may include a silicone-based defoaming agent. Specifically, the silicone-based defoaming agent may include a polysiloxane-based defoaming agent, and the polysiloxane-based defoaming agent may include, for example, one or more of BYK-019, BYK-021, and BYK-094, but is not particularly limited. When a polysiloxane-based defoaming agent is used in this way, the defoaming of the aerogel composition improves the uniformity of the aerogel layer after coating and drying, and further improves the heat insulation properties.

[0055] The amount of the defoaming agent may be 0.05% to 2% by weight, 0.1% to 1% by weight, or 0.1% to 0.5% by weight, relative to the total amount of solids in the aerogel composition. When a battery insulation sheet is manufactured using an aerogel composition containing a defoaming agent within the above range, the uniformity of the battery insulation sheet can be improved.

[0056] In one embodiment, the binder may include an aqueous polymer binder. For example, 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.

[0057] The aqueous polymer may, but is not limited to, include one or more selected from the group consisting of polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinylpyrrolidone.

[0058] The anionic water-soluble polymer may include one or more polymers selected from the group consisting of polymers having functional groups of carboxylic acids, sulfonic acids, sulfate esters, phosphate esters, and salts thereof. For example, the anionic water-soluble polymer may be a polymer having a carboxylic acid group, and a specific example may be polymaleic acid, but is not limited to this.

[0059] The cationic water-soluble polymer may include one or more polymers selected from the group consisting of polymers having functional groups of amines, ammonium, phosphonium, sulfonium, and salts thereof. For example, the cationic water-soluble polymer may be a polymer having an amine group, and as a specific example, it may include one or more polymers selected from the group consisting of polyethyleneamine and polyamine, but is not limited to these.

[0060] 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.

[0061] The binder may include an aqueous polymer and a water-dispersible polymer. For example, it may include an aqueous polymer having dispersion properties in addition to binder properties, and a water-dispersible polyurethane having fire-resistant properties. A specific example is the inclusion of polyvinyl alcohol and a water-dispersible polyurethane.

[0062] The weight ratio of the aqueous polymer and the water-dispersible polymer may be 1:1 to 1:5, 1:1 to 1:4, or 1:2 to 1:3. When the weight ratio of the aqueous polymer and the water-dispersible polymer is mixed within the above range, the heat insulation, dust resistance, and compression properties of the heat-insulating sheet, as well as its fire resistance and mechanical properties, can be further improved.

[0063] The binder content may be 0.5% to 20% by weight, 2% to 15% by weight, or 8% to 15% by weight, relative to the total solid content of the aerogel composition. When a battery insulation sheet is manufactured using an aerogel composition containing a binder within the above range, the dust characteristics of the battery insulation sheet can be improved.

[0064] In one embodiment, the dispersant may include one or more selected from the group consisting of surfactants and phosphate salts. Specifically, the dispersant may include, but is not limited to, one or more nonionic surfactants, anionic surfactants, amphoteric surfactants, natural surfactants such as lecithin, and phosphates.

[0065] If the composition further includes the aforementioned dispersant, the dispersion of the aerogel within the composition can be further improved, and the fibrous support and the aerogel can be uniformly dispersed.

[0066] The content of the dispersant may be 0.1% to 6% by weight, 0.1% to 5% by weight, or 0.1% to 3% by weight, relative to the total solid content of the aerogel composition. When the dispersant is included within the above range, the aerogel composition can be manufactured at low cost, and a battery insulation sheet with excellent heat insulation, uniformity, and dust characteristics can be manufactured using this composition.

[0067] In one embodiment, the binder and the dispersant may be present in weight ratios 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 dispersant are mixed in weight ratios within these ranges, the aerogel can be dispersed more uniformly in the aerogel layer.

[0068] In one embodiment, the aerogel composition may contain, with respect to the total solid content, 25% to 60% by weight of the fibrous support, 30% to 70% by weight of the aerogel, 0.1% to 1% by weight of the defoaming agent, and 2% to 15% by weight of the binder.

[0069] 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, 0.1% to 0.5% by weight of the defoaming agent, and 8% to 15% by weight of the binder, relative to the total solid content of the aerogel composition. When the aerogel composition is composed within this range, it is possible to achieve excellent heat insulation while simultaneously improving durability, enhancing the bonding strength between the fibrous support and the aerogel to prevent dust generation, and improving the uniformity of the heat insulation sheet.

[0070] In one embodiment, the aerogel composition may contain, with respect to the total solid content, 25% to 60% by weight of the fibrous support, 30% to 70% by weight of the aerogel, 0.1% to 1% by weight of the defoaming agent, 2% to 15% by weight of the binder, and 0.1% to 5% by weight of the dispersant.

[0071] 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, 0.1% to 0.5% by weight of the defoaming agent, 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 composed within this range, the dispersibility of the aerogel can be improved, excellent heat insulation properties can be achieved, durability can be improved, the bonding strength between the fibrous support and the aerogel can be improved to prevent dust generation, and the uniformity of the heat insulation sheet can be improved.

[0072] In one embodiment, the aerogel composition may further contain a silane compound. The silane compound may include, for example, one or more selected from the group consisting of 3-(trimethoxysilyl)propyl methacrylate, methyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octadecyltrimethoxysilane, ethyltriethoxysilane, and 3-glycidoxypropyltrimethoxysilane. When the silane compound is further included, the dispersibility can be further improved.

[0073] In one embodiment, additives such as wetting agents, emulsifiers, compatibilizers, viscosity modifiers, pH modifiers, stabilizers, antioxidants, acidic or basic scavengers, metal deactivators, defoamers, antistatic agents, thickeners, adhesion improvers, binders, flame retardants, impact modifiers, pigments, dyes, colorants, and deodorizers may be selectively further included.

[0074] A method for producing an aerogel composition according to one embodiment includes the steps of: mixing a functional substance containing 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; mixing the aerogel mixture with a fibrous support to produce an aerogel composition; and mixing the aerogel composition with an antifoaming agent, wherein the fibrous support may be present in an amount of 5% to 70% by weight, the aerogel in an amount of 10% to 90% by weight, the antifoaming agent in an amount of 0.05% to 2% by weight, and the functional substance in an amount of 0.5% to 20% by weight, relative to the total solid content of the aerogel composition.

[0075] In the step of mixing a functional substance with the aforementioned solvent to produce a solvent mixture, a binder may be mixed with the solvent, or the binder and dispersant may be mixed with the solvent. Here, a specific explanation of the solvent, binder, and dispersant is as described above.

[0076] In the step of mixing the solvent mixture with the aerogel to produce the aerogel mixture, the aerogel may be added in powder form, and a specific description of the aerogel is as described above.

[0077] In the step of mixing the aerogel mixture with the fibrous support to produce the aerogel composition, a specific description of the fibrous support is as described above.

[0078] In the step of mixing the aerogel composition with the defoaming agent, a specific explanation of the defoaming agent is as described above.

[0079] When an antifoaming agent is added to the aerogel composition and mixed, air bubbles in the aerogel composition are removed, and when this is used to manufacture a battery insulation sheet, the uniformity of the fibrous support and aerogel within the aerogel layer can be further improved.

[0080] In each of the following steps, the mixing can be performed using a mixer: mixing a functional substance containing a binder, a dispersant, or a combination thereof with the solvent to produce a solvent mixture; mixing the solvent mixture with an aerogel to produce an aerogel mixture; mixing the aerogel mixture with a fibrous support to produce an aerogel composition; and mixing the aerogel composition with an antifoaming agent. For example, the mixer may include, but is not limited to, a planetary mixer and a thinky mixer.

[0081] As a specific example, a planetary mixer can be used when mixing the solvent mixture with the aerogel. When mixing the solvent mixture with the aerogel using the planetary mixer, the aerogel can be uniformly dispersed in the solvent.

[0082] The planetary mixer may be equipment that can be used to mix or stir other substances in order to produce a homogeneous mixture. It may include a blade capable of planetary motion.

[0083] In one embodiment, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades. Specifically, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades.

[0084] The planetary blades and high-speed dispersion blades rotate continuously around their axes. The rotational speed can be expressed in units of rotations per minute (rpm).

[0085] In one embodiment, the planetary mixer may include a first blade and a second blade having different axes of rotation. 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 rotational speeds between the first blade and the second blade. In a specific example, the first blade may be an open blade and the second blade may be a despa blade.

[0086] The rotational 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. The rotational 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.

[0087] The rotation speed of the second blade in the step of mixing the aerogel composition with the defoaming agent may be lower than the rotation speed of the second blade in one or more of the steps of mixing the solvent mixture with the aerogel to produce an aerogel mixture and mixing the aerogel mixture with the fibrous support to produce an aerogel composition. For example, the rotation speed of the second blade in the step of mixing the aerogel composition with the defoaming agent can be controlled at a speed of 30% to 75%, 40% to 70%, or 40% to 60% of the rotation speed of the second blade in one or more of the steps of mixing the solvent mixture with the aerogel to produce an aerogel mixture and mixing the aerogel mixture with the fibrous support to produce an aerogel composition. In this case, the generation of further bubbles in the composition can be minimized and bubbles can be effectively removed.

[0088] When a functional substance is added to the solvent and mixed, 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, 600 rpm to 1000 rpm, or 700 rpm to 800 rpm. When the solvent and functional substance are mixed as described above, a solvent mixture in which the binder, dispersant, or a combination thereof is uniformly dispersed can be produced, making aerogel mixing easier in subsequent steps.

[0089] 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 a uniform dispersion.

[0090] 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 in the composition are removed, the viscosity is adjusted, and the dispersion of the fibrous support among the uniformly dispersed aerogel is facilitated, and the aerogel may exist in a form in which it surrounds the fibrous support within the composition. Here, a binder is present between the aerogel and the fibrous support, which can improve the binding strength between the aerogel and the fibrous support.

[0091] When mixing the aerogel composition with the defoaming agent, 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 100 rpm to 1000 rpm, 150 rpm to 800 rpm, or 300 rpm to 700 rpm. When mixing the aerogel composition with the defoaming agent under rotation speed conditions within the above ranges, air bubbles in the aerogel composition can be effectively removed.

[0092] The step of dispersing the defoaming agent can be performed for 10 minutes or less, 1 to 10 minutes, or 3 to 8 minutes. If the aerogel composition and the defoaming agent are mixed for more than 10 minutes, the generation of bubbles may actually be promoted, but by performing the step of dispersing the defoaming agent for 10 minutes or less, bubbles in the aerogel composition can be effectively removed.

[0093] Figure 1 is a schematic diagram showing one example of a battery insulation sheet formed between multiple cells.

[0094] Referring to Figure 1, the battery insulation sheet 100 according to one embodiment may be formed between each cell 200 in a battery module containing a plurality of cells 200. Here, the upper and lower surfaces of the battery insulation sheet may be positioned to face each adjacent cell. By forming the battery insulation sheet 100 according to one embodiment between each of the plurality of cells 200, it is possible to block flames within the cells in advance, minimize the spread of flames to other cells, and provide a battery module and a battery pack containing the same with enhanced safety.

[0095] Figure 2 is a schematic diagram showing the structure of a battery insulation sheet based on one actual example.

[0096] Referring to Figure 2, the battery insulation sheet 100 includes a base material 110 and an aerogel layer 120 formed on the base material 110, where the upper and lower surfaces of the battery insulation sheet may be positioned to face adjacent cells, respectively.

[0097] By forming an aerogel layer on the substrate using the aerogel composition according to this embodiment, the battery insulation sheet not only improves in insulation properties but also in uniformity, and prevents the aerogel from detaching and generating dust when the battery insulation sheet is manufactured or installed inside a device.

[0098] The specific description of the aerogel composition that forms the aerogel layer in the aforementioned battery insulation sheet is as described above.

[0099] The aforementioned substrate can be a variety of materials, such as resins, metals, non-metallic inorganic materials, or composites thereof, and its type is not limited. Furthermore, the form of the substrate is not particularly limited, such as films, thin films, or sheets.

[0100] The resin may include, for example, one or more selected from the group consisting of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0101] The aforementioned 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 the aforementioned metal material, the substrate may be subjected to corrosion prevention treatment, insulation treatment, etc., as necessary.

[0102] The inorganic material may include one or more selected from the group consisting of calcium carbonate (CaCO3), talc, and mica.

[0103] As a specific example, the base material may include inorganic materials, and as a more specific example, it may include mica. In this case, the thermal insulation properties and durability of the thermal insulation sheet can be improved.

[0104] In one embodiment, the aerogel layer may be formed as a single layer or a multi-layer structure. If 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.

[0105] Figure 3 is a schematic diagram showing the structure of a battery insulation sheet in another embodiment.

[0106] Referring to Figure 3, in one embodiment, the battery insulation sheet 100 may have a structure comprising 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 arranged to face adjacent cells, respectively. In this case, the first substrate and the second substrate may be formed of the same or different materials.

[0107] A method for manufacturing a battery insulation sheet according to one embodiment may include the steps of: coating the aerogel composition onto a substrate; and drying the aerogel composition coated on the substrate. Here, the substrate may mean the substrate shown in Figure 2 or one of the first and second substrates shown in Figure 3.

[0108] In the method for manufacturing the battery insulation sheet, the specific details regarding the base material and the aerogel composition are as described above.

[0109] The coating step can be carried out by applying an aerogel slurry onto a conventional substrate.

[0110] The coating step may be repeated once or two or more times.

[0111] The drying step can be carried out, for example, under temperature conditions of 25°C to 100°C, 45°C to 90°C, or 60°C to 85°C. By drying under these temperature conditions, a rigid aerogel layer may be formed on the substrate without the need for another adhesive or bonding agent, while preventing detachment between the substrate and the aerogel layer. A coating layer may also be formed in such a way that the aerogel coats the periphery of a plurality of dispersed fibrous supports.

[0112] In one embodiment, the method for manufacturing the battery insulation sheet may further include a step of laminating a substrate onto the coated aerogel composition before drying. In this case, the battery insulation sheet can be manufactured in 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.

[0113] A simple method of coating a substrate with an aerogel composition according to one embodiment and drying it allows for the manufacture of a battery insulation sheet without the use of a separate adhesive or the formation of an adhesive layer. The aerogel is uniformly dispersed, and even at a thin thickness, it exhibits excellent insulation, uniformity, and low dust properties.

[0114] The following describes specific embodiments of the present invention. However, the embodiments described below are merely for illustrative purposes and to explain the present invention, and the invention is not limited thereto. Furthermore, any matters not described herein can be sufficiently inferred by technical analogy by those skilled in the art, and therefore their explanations are omitted.

[0115] (Manufacturing of battery insulation sheets) Example 1 1. Manufacturing of aerogel composition A solvent mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder to ultrapure water, which was used as the solvent, and mixing it under conditions of open blade 30 rpm and despa blade 700 rpm. Subsequently, the solvent mixture was subjected to a BET value of 800 ml. 2Aerogel was added to the mixture at 70 rpm on the open blade and 1500 rpm on the desperation blade to produce an aerogel mixture. Glass wool was added to the aerogel mixture and mixed at 30 rpm on the open blade and 1200 rpm on the desperation blade to produce an aerogel composition. Next, a polysiloxane-based defoaming agent (BYK, BYK-094) was added to the aerogel composition and mixed for 8 minutes at 30 rpm on the open blade and 700 rpm on the desperation blade to remove air bubbles from the aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing. The solid content of the manufactured aerogel composition was confirmed to be 50% by weight of aerogel, 40% by weight of glass wool, 9.9% by weight of polyvinyl alcohol, and 0.1% by weight of an antifoaming agent.

[0116] 2. Manufacturing of battery insulation sheets The manufactured aerogel composition was slurry-coated onto a 0.1 mm thick mica sheet (Famica, Muscovite), and after laminating another 0.1 mm thick mica sheet in a sandwich-type configuration, it was coated using a roll-rolling method. Next, it was dried at 60°C for 24 hours to form an aerogel layer and manufacture a battery insulation sheet. The total thickness of the manufactured battery insulation sheet was confirmed to be 1.38 mm.

[0117] Example 2 The aerogel composition was produced in the same manner as in Example 1, except that the amount of raw materials added during the production of the aerogel composition was adjusted to produce an aerogel composition with a solid content of 50% by weight of aerogel, 40% by weight of glass wool, 9.5% by weight of polyvinyl alcohol, and 0.5% by weight of an antifoaming agent.

[0118] Example 3 The aerogel composition was produced in the same manner as in Example 1, except that the amount of raw materials added during the production of the aerogel composition was adjusted to produce an aerogel composition with a solid content of 50% by weight of aerogel, 40% by weight of glass wool, 8% by weight of polyvinyl alcohol, and 2% by weight of an antifoaming agent.

[0119] Example 4 The aerogel composition was produced in the same manner as in Example 1, except that the amount of raw materials added during the production of the aerogel composition was adjusted to produce an aerogel composition with a solid content of 50% by weight of aerogel, 40% by weight of glass wool, 9.95% by weight of polyvinyl alcohol, and 0.05% by weight of an antifoaming agent.

[0120] Example 5 The aerogel composition was manufactured in the same manner as in Example 1, except that a water-dispersible polyurethane was used as the binder instead of polyvinyl alcohol during the production of the aerogel composition.

[0121] Example 6 1. Manufacturing of aerogel composition A solvent mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder and a surfactant (Triton-X100, Sigma Aldrich) as a dispersant to ultrapure water, which was used as the solvent, and mixing under conditions of open blade 30 rpm and desperation blade 700 rpm. Next, the solvent mixture was subjected to a BET value of 800 m 2 Aerogel was added to the mixture at 70 rpm on the open blade and 1500 rpm on the desperation blade to produce an aerogel mixture. Glass wool was added to the aerogel mixture and mixed at 30 rpm on the open blade and 1200 rpm on the desperation blade to produce an aerogel composition. Next, a polysiloxane-based defoaming agent (BYK, BYK-094) was added to the aerogel composition and mixed for 8 minutes at 30 rpm on the open blade and 700 rpm on the desperation blade to remove air bubbles from the aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing. The solid content of the manufactured aerogel composition was confirmed to be 50% by weight of aerogel, 40% by weight of glass wool, 9.8% by weight of polyvinyl alcohol, 0.1% by weight of dispersant, and 0.1% by weight of antifoaming agent.

[0122] 2. Manufacturing of battery insulation sheets The manufactured aerogel composition was slurry-coated onto a 0.1 mm thick mica sheet (Famica, Muscovite), and after laminating another 0.1 mm thick mica sheet in a sandwich-type configuration, it was coated using a roll-rolling method. Next, it was dried at 60°C for 24 hours to form an aerogel layer and manufacture a battery insulation sheet. The total thickness of the manufactured battery insulation sheet was confirmed to be 1.38 mm.

[0123] Example 7 1. Manufacturing of aerogel composition A solvent mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder, water-dispersible polyurethane, and a surfactant (Triton-X100, Sigma Aldrich) as a dispersant to ultrapure water, which was used as the solvent, and mixing under conditions of open blade 30 rpm and despa blade 700 rpm. Next, the solvent mixture was subjected to a BET value of 800 m 2 Aerogel was added at a rate of 1 / g and mixed at an open blade speed of 70 rpm and a despa blade speed of 1500 rpm to produce an aerogel mixture. Glass wool was added to the aerogel mixture and mixed at an open blade speed of 30 rpm and a despa blade speed of 1200 rpm to produce an aerogel composition. Next, a polysiloxane-based defoaming agent (BYK, BYK-094) was added to the aerogel composition and mixed for 8 minutes at an open blade speed of 30 rpm and a despa blade speed of 700 rpm to remove air bubbles from the aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing. The solid content of the manufactured aerogel composition was confirmed to be 50% by weight of aerogel, 40% by weight of glass wool, 3% by weight of polyvinyl alcohol, 6.8% by weight of water-dispersible polyurethane, 0.1% by weight of dispersant, and 0.1% by weight of antifoaming agent.

[0124] 2. Manufacturing of battery insulation sheets The manufactured aerogel composition was slurry-coated onto a 0.1 mm thick mica sheet (Famica, Muscovite), and after laminating another 0.1 mm thick mica sheet in a sandwich-type configuration, it was coated using a roll-rolling method. Next, it was dried at 60°C for 24 hours to form an aerogel layer and manufacture a battery insulation sheet. The total thickness of the manufactured battery insulation sheet was confirmed to be 1.38 mm.

[0125] Comparative Example 1 The aerogel composition was produced in the same manner as in Example 1, except that the amount of raw materials added during the production of the aerogel composition was adjusted to produce an aerogel composition with a solid content of 50% by weight of aerogel, 40% by weight of glass wool, 9.99% by weight of polyvinyl alcohol, and 0.01% by weight of an antifoaming agent.

[0126] Comparative Example 2 The aerogel composition was produced in the same manner as in Example 1, except that the amount of raw materials added during the production of the aerogel composition was adjusted to produce an aerogel composition with a solid content of 50% by weight of aerogel, 40% by weight of glass wool, 7% by weight of polyvinyl alcohol, and 3% by weight of an antifoaming agent.

[0127] <Example of experiment> Experimental Example 1: Evaluation of Thermal Insulation The thermal insulation properties were evaluated using the thermal insulation sheets manufactured in Examples 1-7 and Comparative Examples 1-2. Specifically, a heat insulating sheet was placed between a pair of opposing 1mm thick aluminum plates and placed on a heat press. The upper plate of the heat press was heated to 350°C, while the lower plate was not heated and maintained at a starting temperature of 40°C. Next, a pressure of 20kN was applied to the lower plate of the heat press, and the temperature of the lower plate was measured after 11 minutes, as shown in Table 1 below.

[0128] Experimental Example 2: Evaluation of Dust Resistance The dust-free properties were evaluated using the heat-insulating sheets manufactured in Examples 1-7 and Comparative Examples 1-2. Specifically, the weight of each insulation sheet was measured before evaluation. Next, the insulation sheet was placed on a rubber plate, and five points on the sheet (the top and the exact center) were struck evenly with a rubber hammer to remove dust, after which the weight of the insulation sheet was measured again. Subsequently, the weight before and after the physical impact was compared to calculate the weight reduction rate, and the results are shown in Table 1 below.

[0129] Experimental Example 3: Evaluation of Uniformity The uniformity was evaluated using the heat insulating sheets manufactured in Examples 1-7 and Comparative Examples 1-2. Specifically, the sheets were placed on an LED lightbox with a maximum brightness of 1000 lm or more, and the presence, size, and number of pinholes were identified to check the uniformity of the sheets themselves. The results are shown in Table 1 below, and as shown in Figure 4, a sheet with no pinholes and a clean appearance is indicated by ◎, a sheet with pinholes but a small area is indicated by ○, a sheet with pinholes but a large area is indicated by △, and a sheet with almost no uniformity and unusable is indicated by X.

[0130] [Table 1]

[0131] Referring to Table 1 above, it was confirmed that in Examples 1 to 7, the thermal insulation, dust resistance, and uniformity were all excellent. Looking at Examples 1 to 4, it can be seen that the thermal insulation, dust resistance, and uniformity change depending on the component content of the aerogel composition. In Example 5, although the dust resistance decreased somewhat because the binder could not act as a dispersant, it was confirmed that the thermal insulation was improved. In Example 6, when the binder and dispersant were mixed, it was confirmed that the thermal insulation, dust resistance, and uniformity were improved. In Example 7, when polyvinyl alcohol and a water-dispersible polyurethane binder were mixed and a dispersant was included, it was confirmed that the thermal insulation, dust resistance, and uniformity were further improved. Here, it was confirmed that the coating of the thermal insulation sheet became more uniform and there were almost no empty spaces inside the thermal insulation sheet, thus further improving the thermal insulation.

[0132] On the other hand, in the case of Comparative Examples 1 and 2, it was confirmed that the thermal insulation, dust resistance, and uniformity were significantly reduced compared to the Examples.

[0133] Therefore, it was confirmed that the aerogel composition used in this example exhibits excellent thermal insulation, uniformity, and low dust characteristics.

[0134] Although preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, 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]

[0135] 100 Battery Insulation Sheets 110 Base material 120 Aerogel layer 130 First base material 140 Second base material 200 cells

Claims

1. solvent; Fibrous support; aerogel; Defoaming agents; and A functional substance comprising a binder, or a combination of a binder and a dispersant; The aforementioned binder is an aqueous polymer binder. The aforementioned defoaming agent includes a silicone-based defoaming agent. The aerogel composition contains, with respect to the total solid content, the fibrous support in an amount of 5% to 40% by weight, the aerogel in an amount of 50% to 90% by weight, the antifoaming agent in an amount of 0.05% to 2% by weight, and the functional substance in an amount of 0.5% to 20% by weight. An aerogel composition for a battery heat insulating sheet, wherein the aerogel content is greater than the fibrous support content.

2. The aerogel composition for battery heat insulation sheets according to claim 1, wherein the solvent comprises one or more selected from the group consisting of polar solvents and nonpolar solvents.

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

90.

4. The aerogel composition for battery insulation sheets according to claim 1, wherein the fibrous support comprises one or more selected from the group consisting of natural fibers, silica fibers, glass fibers, carbon fibers, basalt fibers, and polymer fibers.

5. The aerogel has a BET specific surface area of ​​500 m². ２ / g to 1,000m ２ The aerogel composition for battery heat insulation sheets according to claim 1, wherein the amount is / g.

6. The aerogel composition for battery heat insulation sheets according to claim 1, wherein the aqueous polymer binder comprises one or more selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

7. The aerogel composition for battery heat insulation sheets according to claim 1, wherein the binder is contained in an amount of 0.5% to 20% by weight relative to the total amount of solids in the aerogel composition.

8. The binder comprises an aqueous polymer and a water-dispersible polymer. The aerogel composition for battery heat insulation sheets according to claim 1, wherein the aqueous polymer and the water-dispersible polymer are contained in a weight ratio of 1:1 to 1:

5.

9. The aerogel composition for battery heat insulation sheets according to claim 1, wherein the dispersant comprises one or more selected from the group consisting of surfactants and phosphate salts.

10. The aerogel composition for battery heat insulation sheets according to claim 1, wherein the dispersant is contained in an amount of 0.1% to 6% by weight relative to the total amount of solids in the aerogel composition.

11. The aerogel composition for a battery heat insulating 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.

12. The aerogel composition for a battery heat insulating sheet according to claim 1, comprising 25% to 40% by weight of the fibrous support, 50% to 70% by weight of the aerogel, 0.1% to 1% by weight of the defoaming agent, and 2% to 15% by weight of the binder, based on the total amount of solids in the aerogel composition.

13. The aerogel composition for a battery heat insulating sheet according to claim 1, comprising, with respect to the total amount of solids in the aerogel composition, 25% to 40% by weight of the fibrous support, 50% to 70% by weight of the aerogel, 0.1% to 1% by weight of the defoaming agent, 2% to 15% by weight of the binder, and 0.1% to 3% by weight of the dispersant.

14. The process involves mixing a functional substance containing a binder, or a combination of a binder and a dispersant, with a solvent to produce a solvent mixture; The steps include: mixing the solvent mixture with the aerogel to produce an aerogel mixture; The steps include: mixing the aerogel mixture with a fibrous support to produce an aerogel composition; The steps include: mixing the aerogel composition with an antifoaming agent; The aforementioned binder is an aqueous polymer binder. The aforementioned defoaming agent includes a silicone-based defoaming agent. The aerogel composition contains, with respect to the total solid content, the fibrous support in an amount of 5% to 40% by weight, the aerogel in an amount of 50% to 90% by weight, the antifoaming agent in an amount of 0.05% to 2% by weight, and the functional substance in an amount of 0.5% to 20% by weight. A method for producing an aerogel composition, wherein the content of the aerogel is greater than the content of the fibrous support.

15. In the method for producing the aerogel composition, at each step, the mixture is mixed using a mixer. The mixer includes a low-speed first blade and a high-speed second blade. The method for producing an aerogel composition according to claim 14, wherein the rotation speed of the second blade in the step of mixing the aerogel composition with an antifoaming agent is 30% to 75% of the rotation speed of the second blade in any one or more of the steps of mixing the solvent mixture with the aerogel to produce an aerogel mixture and mixing the aerogel mixture with a fibrous support to produce an aerogel composition.

16. With the base material; The substrate includes; The aerogel layer is formed using the aerogel composition described in any one of claims 1 to 13, and is a battery heat insulating sheet.

17. The steps include: coating a substrate with the aerogel composition according to any one of claims 1 to 13; A method for producing a battery heat insulating sheet, comprising the step of drying an aerogel composition coated on the substrate;

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