Heat insulating composition for battery device, manufacturing method thereof, sheet manufactured using the same, and battery module including the same

Abstract

To provide an aerogel composition having improved thermal insulation, fire resistance, mechanical properties, and / or dustiness, a method for preparing the aerogel composition, a battery insulation sheet formed using the aerogel composition, and a method for preparing the battery insulation sheet.SOLUTION: The present invention relates to an aerogel composition for battery insulation sheets, the aerogel composition including a reinforcement material including a first fibrous support and a second fibrous support, an aerogel, a functional material including a binder, a dispersant, or a combination thereof, and a solvent, wherein the first fibrous support and the second fibrous support have different ingredients. The present invention also relates to a method for preparing the aerogel composition, a battery insulation sheet formed using the aerogel composition, and a method for preparing the battery insulation sheet.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an aerogel composition for a battery insulating sheet, a method for producing the same, a battery 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. In recent years, interest in electric vehicles has grown to prevent environmental pollution, and high-capacity secondary batteries are being adopted for electric vehicles. Such secondary batteries are required to have characteristics such as high density, high output, and stability.

[0003] On the other hand, when a battery contains a large number of high-capacity cells such as lithium secondary batteries, one cell may overheat for some reason and experience thermal runaway, adversely affecting other adjacent cells, so it is required that adjacent cells are thermally insulated from each other.

[0004] Therefore, conventionally, plates or insulating resin plates are placed between the cells to insulate and heat the adjacent cells.

[0005] The above-mentioned information disclosed in the background of the invention is merely intended to enhance understanding of the background of the invention, and therefore may 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, fire resistance, mechanical properties, and low dust properties, a method for manufacturing the same, a battery insulation sheet formed using the same, and a method for manufacturing the same. [Means for solving the problem]

[0007] One embodiment provides an aerogel composition for a battery insulation sheet, comprising: a reinforcing material including a first fibrous support and a second fibrous support; an aerogel; a functional material including a binder, a dispersant, or a combination thereof; and a solvent, wherein the first fibrous support and the second fibrous support have different constituents.

[0008] The material of each of the first fibrous support and the second fibrous support may be one or more selected from the group consisting of glass, silica, basalt, alumina, silicon carbide, boron, ceramic, and quartz, and the form of each of the first fibrous support and the second fibrous support may be one or more selected from the group consisting of powder, fiber, wool, chop, felt, batting, and lofty batting.

[0009] The first fibrous support may be silica fiber, and the second fibrous support may be glass wool or silica wool.

[0010] The first fibrous support and the second fibrous support may be contained in a weight ratio of 1:5 to 5:1.

[0011] The first fibrous support and the second fibrous support may each have an average length of 50 μm to 20,000 μm and an average diameter of 0.1 μm to 30 μm.

[0012] The aerogel has a BET specific surface area of ​​500 m 2 / g~1,000m 2 / g.

[0013] The average particle size of the aerogel (D 50 ) may be 5 μm to 200 μm.

[0014] The binder includes a water-based polymer binder, and the water-based polymer binder may be one or more selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

[0015] 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.

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

[0017] 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.

[0018] The solvent may be one or more selected from the group consisting of polar solvents and non-polar solvents.

[0019] The weight ratio of the solvent to the total amount of solids in the aerogel composition may be 1:1 to 1:90.

[0020] The aerogel composition may contain 5 to 70% by weight of the reinforcing material, 10 to 90% by weight of the aerogel, and 0.5 to 20% by weight of the functional material, based on the total solid content of the aerogel composition.

[0021] Another embodiment provides a method for producing an aerogel composition for a battery insulation sheet, the method including: 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 reinforcing material to produce an aerogel composition, wherein the reinforcing material includes a first fibrous support and a second fibrous support, and the first fibrous support and the second fibrous support have different constituent components.

[0022] Yet another embodiment provides a battery insulation sheet including a first substrate, a second substrate, and an aerogel layer formed between the first substrate and the second substrate, the aerogel layer being formed using the aerogel composition.

[0023] Each of the first substrate and the second substrate may include a resin, a metal, an inorganic material other than a metal, or a composite of any of these.

[0024] Within the aerogel layer, each of the first and second fibrous supports may have a vertical orientation, a horizontal orientation, or a combination thereof.

[0025] Yet another embodiment provides a method for producing a battery insulation sheet, the method including: applying the aerogel composition onto a first substrate; and laminating a second substrate onto the applied aerogel composition to produce a laminate.

[0026] The method may further comprise the step of pressing and drying the laminate after the step of producing the laminate. [Effects of the Invention]

[0027] A battery insulation sheet manufactured using an aerogel composition according to an embodiment has excellent thermal insulation properties and fire resistance, as well as excellent mechanical properties such as durability and compressibility, and can be manufactured at low cost. Furthermore, the generation of aerogel dust during manufacturing and use can be prevented. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a schematic diagram illustrating the structure of a battery insulation sheet according to an embodiment. [Figure 2] 1 is a schematic diagram illustrating a battery insulation sheet formed between a plurality of cells according to an embodiment. FIG. [Figure 3] 1 is an SEM image of an aerogel layer of a battery heat insulating sheet according to Example 1. [Figure 4]10 is an SEM image of the aerogel layer of the battery heat insulating sheet according to Example 4. [Figure 5] 10 is an SEM image of the aerogel layer of the battery heat insulating sheet according to Example 7. [Figure 6] 1 is an SEM image of the aerogel layer of the battery insulation sheet according to Comparative Example 1. [Figure 7] 4 is a photograph showing the results of a fire resistance evaluation of the battery insulation sheets of Examples 1 and 6. DETAILED DESCRIPTION OF THE INVENTION

[0029] 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 various different forms and is not limited to the embodiments set forth herein.

[0030] Insulation is a material that prevents heat from moving from a high temperature area to a low temperature area, and is used in a variety of industrial fields, including refrigerators, freezer warehouses, and buildings, as well as the aircraft, electronic parts, and automotive industries.

[0031] Such a heat insulating material must have excellent heat insulating properties due to low thermal conductivity, and must also have sufficient mechanical strength to maintain such heat insulating properties.

[0032] Meanwhile, aerogel is a transparent or translucent cutting-edge material with a nanoporous structure. It has very low density and low thermal conductivity, so it not only has great potential as an insulating material, but is also considered a highly efficient super-insulating material that can be used in various industrial fields.

[0033] Furthermore, the greatest advantage of aerogel is that it exhibits lower thermal conductivity than conventional organic insulation materials such as styrofoam, and that it can solve the fatal weaknesses of organic insulation materials, namely their vulnerability to fire and the generation of toxic gases during a fire.

[0034] However, aerogels generally have very low strength due to their high brittleness, making them susceptible to even small impacts, 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. An aerogel composition according to one embodiment includes a reinforcing material including a first fibrous support and a second fibrous support, an aerogel, a functional material including a binder, a dispersant, or a combination thereof, and a solvent, and the first fibrous support and the second fibrous support may have different components. The different components of the first fibrous support and the second fibrous support may mean that the materials and / or shapes of the fibrous supports are different from each other.

[0035] The battery insulation sheet manufactured from the aerogel composition comprising the above components has excellent heat insulation properties, fire resistance, and mechanical properties, has low manufacturing costs, and can prevent the generation of aerogel dust during the manufacturing process and use, thereby improving the safety of the battery.

[0036] In one embodiment, the reinforcing material includes a first fibrous support and a second fibrous support having different components, and the mechanical properties of the battery insulation sheet formed using this can be improved.

[0037] Each of the first fibrous support and the second fibrous support may include fibers used as supports for conventional thermal insulating materials. Hereinafter, the fibrous support can refer to each of the first fibrous support and the second fibrous support, even if the term "first" or "second" is not specified.

[0038] The fibrous support may be one or more fibers selected from the group consisting of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers.

[0039] The natural fiber may be, for example, one or more selected from the group consisting of hemp, jute, flax, coir, hemp, and cellulose.

[0040] The ceramic fibers may be one or more selected from the group consisting of silicon carbide, silicon nitride, boron nitride, and aluminum silicon carbide.

[0041] The mineral fibers may be, for example, mineral fibers containing one or more selected from the group consisting of basalt, wollastonite, alumina, boron, quartz, silica, and slag.

[0042] The polymer fiber may be, 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, one or more of polyimide, polyamide, and polybenzimidazole.

[0043] The form of the fibrous support may be, for example, one or more of powder, fiber, wool, chop, felt, batting, and lofty batting, but is not limited thereto. Fiber may refer to the general shape of a long, thin thread.

[0044] The material of each of the first fibrous support and the second fibrous support may be at least one selected from the group consisting of glass, silica, basalt, alumina, silicon carbide, boron, ceramic, and quartz. The form of each of the first fibrous support and the second fibrous support may be at least one selected from the group consisting of powder, fiber, wool, chopped glass, felt, batting, and lofty batting. As a specific example, the first fibrous support may be silica fiber or glass chopped strands, and the second fibrous support may be glass wool or silica wool. As a more specific example, the first fibrous support may be silica fiber, and the second fibrous support may be glass wool or silica wool. By including different types of first fibrous support and second fibrous support, the mechanical properties of the battery insulation sheet can be further improved.

[0045] The first fibrous support and the second fibrous support may be included in a weight ratio of 1:5 to 5:1, 1:4 to 4:1, or 1:3 to 3:1. By including the first fibrous support and the second fibrous support in a weight ratio within this range, the mechanical properties of the battery insulation sheet can be further improved.

[0046] The average length of the fibrous supports may be, for example, 50 μm to 20,000 μm, 100 μm to 12,000 μm, 100 μm to 5,000 μm, or 3,000 μm to 12,000 μm. Here, the average length of the fibrous supports refers to the average length of each of the first and second fibrous supports. When fibrous supports having an average length within this range are included, the aerogel layer can be formed firmly and mechanical properties can be improved.

[0047] The average diameter of the fibrous supports may be, for example, 0.1 μm to 30 μm, 8 μm to 20 μm, 8 μm to 12 μm, or 10 μm to 20 μm. Here, the average diameter of the fibrous supports refers to the average diameter of each of the first and second fibrous supports. By including fibrous supports having an average diameter within this range, the structure of the aerogel layer can be made more robust, and production costs can be reduced.

[0048] The first fibrous support may have an average diameter of 8 μm to 12 μm and an average length of 100 μm to 20,000 μm, and the second fibrous support may have an average diameter of 10 μm to 20 μm and an average length of 3 μm to 12 μm. By including a first fibrous support and a second fibrous support having average diameters and average lengths within these ranges, it is possible to improve porosity and orientation, and also to improve compression characteristics.

[0049] The content of the reinforcing material may be 5 to 70 wt %, 25 to 60 wt %, or 30 to 50 wt %, 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 this range, the mechanical properties 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 / g. By including an aerogel having a BET specific surface area value within this 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 average particle size of the aerogel (D 50) may be 5 μm to 200 μm, 10 μm to 100 μm, or 20 μm to 50 μm. By including an aerogel having an average particle size within this range, it is possible to improve the heat insulating properties and retard heat transfer between multiple cells.

[0052] Average particle size (D 50 ) can be measured, for example, using the laser diffraction method or scanning electron microscope (SEM) photographs, and the average particle size (D 50 ) can be defined as the particle size at 50% of the particle size distribution (the particle size corresponding to 50% of the cumulative volume of the particle size distribution).

[0053] The aerogel content 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 within this range, the heat insulating properties of the battery insulation sheet can be improved.

[0054] In one embodiment, the binder may include a water-based polymer binder, for example, the water-based polymer binder may be one or more selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

[0055] The water-soluble polymer may be, for example, one or more selected from the group consisting of polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinylpyrrolidone, but is not limited thereto.

[0056] 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 a specific example thereof may include, but is not limited to, polymaleic acid.

[0057] The cationic water-soluble polymer may include at least one 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 include, but are not limited to, at least one selected from the group consisting of polyethylene amine and polyamine.

[0058] The water-dispersible polymer may be at least one selected from the group consisting of water-dispersible polyurethane and water-dispersible polyester, but is not limited thereto.

[0059] The binder may include a water-based polymer and a water-dispersible polymer, for example, a water-based polymer having binder properties as well as dispersing properties, and a water-dispersible polyurethane having fire-resistant properties, and specific examples thereof include polyvinyl alcohol and water-dispersible polyurethane.

[0060] 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. By using the aqueous polymer and the water-dispersible polymer in combination at 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.

[0061] The binder content 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.

[0062] In one embodiment, the dispersant may be one or more selected from the group consisting of surfactants and phosphate salts. Specific examples of the dispersant include, but are not limited to, one or more of nonionic surfactants, anionic surfactants, amphoteric surfactants, natural surfactants such as lecithin, and phosphate salts.

[0063] When a 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.

[0064] 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 this range, the aerogel composition can be produced at low cost, and thereby a battery insulation sheet with excellent heat insulation properties, fire resistance, mechanical properties, and dust resistance can be produced.

[0065] In one embodiment, the binder and 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. Using the binder and dispersant in combination in a weight ratio within this range may allow the aerogel to be more uniformly dispersed in the aerogel layer.

[0066] In one embodiment, the aerogel composition may contain 25% to 60% by weight of the reinforcing material, 30% to 70% by weight of the aerogel, and 2% to 15% by weight of the binder, based on the total solid content of the aerogel composition.

[0067] As a specific example, the aerogel composition may contain 30 to 50% by weight of the reinforcing material, 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. By configuring the aerogel composition within these ranges, it is possible to achieve excellent thermal insulation and fire resistance, while also improving mechanical properties. It is also possible to improve the bonding strength between the reinforcing material and the aerogel, thereby preventing dust generation.

[0068] In one embodiment, the aerogel composition may contain 25% to 60% by weight of the reinforcing material, 30% to 70% by weight of the aerogel, 2% to 15% by weight of the binder, and 0.1% to 5% by weight of the dispersant, based on the total solid content.

[0069] As a specific example, the aerogel composition may contain 30 to 50% by weight of reinforcing material, 40 to 60% by weight of aerogel, 5 to 10% by weight of binder, and 0.1 to 3% by weight of dispersant, relative to the total solid content. By configuring the aerogel composition within these ranges, the dispersibility of the aerogel can be improved, achieving excellent thermal insulation and fire resistance, while further improving mechanical properties. The bonding strength between the reinforcing material and the aerogel can be improved, preventing dust generation.

[0070] In one embodiment, the solvent may be one or more selected from the group consisting of polar solvents and non-polar solvents.

[0071] The polar solvent may be water, an alcohol-based solvent, or a combination thereof.

[0072] The water may include, for example, purified water, ultra-pure water, or a combination thereof.

[0073] The alcohol-based solvent may be, for example, one or more selected from the group consisting of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol, and glycerol, but is not limited thereto.

[0074] 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.

[0075] 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 the hydrophobic aerogel. In one embodiment, however, the aerogel is uniformly dispersed by controlling the mixing process design, mixing conditions, and the amounts of binder and dispersant added. Uniformly dispersing the aerogel in the composition in this manner allows for the formation of a thin battery insulation sheet with excellent insulation properties, fire resistance, mechanical properties, and low dust, even without the need for a large amount of binder.

[0076] 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 this range, the viscosity can be controlled and the aerogel layer can be coated.

[0077] In one embodiment, the aerogel composition may further include a silane-based compound. The silane-based compound may be, for example, one or more selected from the group consisting of 3-(trimethoxysilyl)propylmethacrylate, methyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octadecyltrimethoxysilane, ethyltriethoxysilane, and 3-glycidoxypropyltrimethoxysilane. The inclusion of a silane-based compound may further improve dispersibility.

[0078] In one embodiment, the composition may further optionally contain additives such as wetting agents, emulsifiers, compatibilizers, viscosity adjusters, pH adjusters, stabilizers, antioxidants, acidic or basic scavengers, metal deactivators, antifoaming agents, antistatic agents, thickeners, adhesion improvers, binders, flame retardants, impact modifiers, pigments, dyes, colorants, and deodorizers.

[0079] 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 reinforcing material to produce an aerogel composition. The reinforcing material includes a first fibrous support and a second fibrous support, and the first fibrous support and the second fibrous support may have different constituent components.

[0080] In the process of preparing a solvent mixture by mixing a functional material with a solvent, a binder may be mixed with the solvent, or a binder and a dispersant may be mixed with the solvent. Here, the specific description of the solvent, binder, and dispersant may be as described above.

[0081] In the process 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 may be the same as that described above.

[0082] In the step of producing an aerogel composition by mixing an aerogel mixture with a reinforcing material, the specific explanations regarding the first fibrous support, the second fibrous support, and the reinforcing material may be as described above.

[0083] In each of the steps of preparing a solvent mixture by mixing a functional material, such as a binder, a dispersant, or a combination thereof, with a solvent, preparing an aerogel mixture by mixing the solvent mixture with an aerogel, and preparing an aerogel composition by mixing the aerogel mixture with a reinforcing material, 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.

[0084] As a specific example, a planetary mixer can be used to mix the solvent mixture and the aerogel. By using a planetary mixer to mix the solvent mixture and the aerogel, the aerogel can be uniformly dispersed in the solvent.

[0085] A planetary mixer may be a device that can be used to mix or stir different materials to produce a homogeneous mixture. It may include blades that can move in planetary motion.

[0086] In one embodiment, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades. As a specific example, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades.

[0087] The planetary blades and high-speed dispersion blades rotate continuously about their axes, and the rotational speed may be expressed in units of rotations per minute (rpm).

[0088] 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 of the first blade and the second blade. As a specific example, the first blade may be an open blade and the second blade may be a Despa blade.

[0089] 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.

[0090] 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. Mixing the solvent and functional material in this manner produces a solvent mixture in which the binder, dispersant, or a combination thereof is uniformly dispersed, making it easier to mix the aerogel in the subsequent process.

[0091] When mixing the solvent mixture and 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. By adding the aerogel to the solvent mixture and mixing it in this manner, it is possible to prevent the aerogel from agglomerating with each other and induce uniform dispersion.

[0092] When mixing the aerogel mixture and 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. Mixing the aerogel mixture and the fibrous support in this manner removes air bubbles from the composition, adjusts the viscosity, and facilitates dispersion of the fibrous support among the uniformly dispersed aerogel, allowing the aerogel to exist in a form in which it surrounds the fibrous support in the composition. The presence of a binder between the aerogel and the fibrous support can improve the bonding strength between the aerogel and the fibrous support.

[0093] In one embodiment, the battery insulation sheet includes a first substrate, a second substrate, and an aerogel layer formed between the first substrate and the second substrate, and the aerogel layer may be formed using the aerogel composition according to one embodiment described above.

[0094] FIG. 1 is a schematic diagram showing the structure of a battery insulation sheet according to one embodiment.

[0095] Referring to FIG. 1 , in one embodiment, a battery insulation sheet 100 may have a structure including a first substrate 110, an aerogel layer 120 formed on the first substrate 110, and a second substrate 130 formed on the aerogel layer 120. In the aerogel layer 120, the first fibrous support 121 is shown with a thick line, and the second fibrous support 122 is shown with a thin line. Here, other components are omitted to specifically illustrate the dispersion morphology of the first fibrous support 121 and the second fibrous support 122. Therefore, it should not be interpreted that the aerogel layer does not contain components other than the reinforcing material. In the aerogel layer 120, the first fibrous support 121 and the second fibrous support 122 may be oriented vertically and horizontally, respectively. In FIG. 1 , the first substrate 110 and the second substrate 130 may be formed of the same or different materials.

[0096] By forming an aerogel layer using the aerogel composition according to one embodiment between the first and second substrates, the battery insulation sheet has improved mechanical properties as well as thermal insulation and fire resistance, and can prevent the aerogel from falling off and generating dust when the battery insulation sheet is manufactured or installed inside a device.

[0097] FIG. 2 is a schematic diagram showing a battery insulating sheet according to one embodiment formed between a plurality of cells.

[0098] 2, 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, i.e., the first and second substrates of the battery insulation sheet, may be disposed to face the adjacent cells. By forming the battery insulation sheet 100 according to an embodiment between each of the plurality of cells 200, it is possible to prevent a flame from spreading to other cells by blocking the flame in advance, thereby providing a battery module and a battery pack including the same with improved safety.

[0099] In the battery insulating sheet, the specific description of the aerogel composition forming the aerogel layer may be as described above.

[0100] The first substrate and the second substrate may each be made of various materials, such as resin, metal, inorganic material other than metal, or a composite thereof, and are not limited to their types. The form of the substrate may be a film, thin film, sheet, or the like, and is not particularly limited.

[0101] The resin may be, for example, one or more selected from the group consisting of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0102] The metal may be, 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 a metal substrate is used, the substrate may be subjected to corrosion prevention treatment, insulation treatment, etc., as necessary.

[0103] The inorganic material may be one or more selected from the group consisting of calcium carbonate (CaCO3), talc, and mica.

[0104] As a specific example, the first substrate and the second substrate may include an inorganic material, and more specifically, may include mica, which can improve the heat insulating properties and durability of the heat insulating sheet.

[0105] In one embodiment, the first fibrous support and the second fibrous support may each have a vertical orientation, a horizontal orientation, or a combination thereof within the aerogel layer. As a specific example, the first fibrous support and the second fibrous support may each have a uniform vertical and horizontal orientation within the aerogel layer. In this case, the compression characteristics of the aerogel layer are improved, and the aerogel layer can absorb pressure on adjacent cells during cell deterioration and expansion, thereby improving battery safety.

[0106] In one embodiment, the aerogel layer may be formed in a single layer structure or a multi-layer structure. When the aerogel layer is formed in a multi-layer structure, the aerogel layer may be formed in 2 to 10 layers, 2 to 7 layers, or 2 to 5 layers.

[0107] A method for manufacturing an embodiment of a battery insulation sheet may include a step of applying an embodiment of an aerogel composition onto a first substrate, and a step of laminating a second substrate on the applied aerogel composition to manufacture a laminate.

[0108] In the method for producing a battery insulation sheet, the specific description of the substrate and the aerogel composition may be as described above.

[0109] The step of applying the aerogel slurry onto the first substrate and the step of laminating the second substrate onto the applied aerogel slurry may be carried out by a conventional method.

[0110] The step of applying the aerogel slurry onto the first substrate may be carried out once, or may be repeated two or more times.

[0111] In one embodiment, after the laminate is produced, the method may further include the step of pressing and drying the laminate.

[0112] The drying step may be carried out under temperature conditions of, for example, 25°C to 100°C, 45°C to 90°C, or 60°C to 85°C. Drying under these temperature conditions allows a solid aerogel layer to be formed on the substrate without the need for a separate adhesive member or adhesive while preventing detachment between the substrate and the aerogel layer, and a coating layer can be formed in which the aerogel coats the peripheries of the plurality of dispersed first fibrous supports and second fibrous supports.

[0113] According to one embodiment, a battery insulation sheet can be manufactured without using a separate adhesive or forming an adhesive layer by simply applying an aerogel composition to a first substrate, laminating a second substrate on the aerogel composition to produce a laminate, and then pressing and drying the laminate. Because the aerogel is uniformly dispersed, the sheet can achieve excellent insulation, fire resistance, mechanical properties, and low dust even at a thin thickness.

[0114] Specific examples of the present invention will be presented below. However, the examples described below are merely for the purpose of specifically illustrating or explaining the present invention, and the present invention should not be limited thereto. Furthermore, since the contents not described here can be sufficiently inferred by those skilled in the art, a description thereof will be omitted.

[0115] (battery insulation sheet manufacturing) Example 1 1. Aerogel Composition Preparation Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) was added as a binder to ultrapure water as a solvent, and then mixed with an open blade at 30 rpm and a despa blade at 700 rpm to produce a solvent mixture. 2 An aerogel mixture was prepared by adding aerogel (1 / g) and mixing with an open blade at 70 rpm and a Despa blade at 1500 rpm. Silica fiber (first fibrous support) and glass wool (second fibrous support) were added as reinforcing materials in a weight ratio of 1:3 to the aerogel mixture, and then mixed with an open blade at 30 rpm and a Despa blade at 1200 rpm to prepare an aerogel composition. A planetary mixer (DIENTEK, PT-005) was used for mixing.

[0116] The solids content of the produced aerogel composition was determined to be 50 wt% aerogel, 40 wt% reinforcing material, and 10 wt% polyvinyl alcohol.

[0117] 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 coated using a roll rolling method. 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.

[0118] Example 2 The same method as in Example 1 was used to prepare an aerogel composition, except that silica fiber and glass wool were added to the aerogel mixture in a weight ratio of 1:1 and mixed.

[0119] Example 3 The same method as in Example 1 was used to prepare the aerogel composition, except that silica fiber and glass wool were added to the aerogel mixture in a weight ratio of 3:1 and mixed.

[0120] Example 4 The aerogel composition was prepared in the same manner as in Example 1, except that silica fiber and glass wool were added to the aerogel mixture in a weight ratio of 1:4 and mixed together to prepare the aerogel composition.

[0121] Example 5 The same method as in Example 1 was used to prepare the aerogel composition, except that silica fiber and glass wool were added to the aerogel mixture in a weight ratio of 4:1 and mixed.

[0122] Example 6 The aerogel composition was produced in the same manner as in Example 1, except that ceramic wool was added to the aerogel mixture instead of glass wool and mixed to produce the aerogel composition.

[0123] Example 7 The aerogel composition was produced in the same manner as in Example 1, except that glass chopped strands were added to the aerogel mixture instead of silica fibers and mixed to produce the aerogel composition.

[0124] Example 8 The aerogel composition was produced in the same manner as in Example 1, except that glass chopped strands were added to the aerogel mixture instead of silica fiber and ceramic wool was added to the aerogel mixture instead of glass wool, and the mixture was mixed to produce the aerogel composition.

[0125] Example 9 1. Aerogel Composition Preparation Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder and surfactant (Triton-X100, Sigma Aldrich) as a dispersant were added to ultrapure water as a solvent, and then mixed under conditions of an open blade of 30 rpm and a desparate blade of 700 rpm to prepare a solvent mixture. 2 An aerogel mixture was prepared by adding aerogel (weight: 1 / g) and mixing with an open blade at 70 rpm and a Despa blade at 1500 rpm. Silica fiber and glass wool were added as reinforcing materials to the aerogel mixture in a weight ratio of 1:3 and mixing was performed with an open blade at 30 rpm and a Despa blade at 1200 rpm. A planetary mixer (DN Tech, PT-005) was used for mixing.

[0126] The solids content of the produced aerogel composition was determined to be 50 wt% aerogel, 40 wt% reinforcing material, 9.9 wt% polyvinyl alcohol, and 0.1 wt% dispersant.

[0127] 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 coated using a roll rolling method. 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.

[0128] Comparative Example 1 1. Aerogel Composition Preparation The solvent was ultrapure water, and polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) was used as a binder. 2 / g of aerogel was added and mixed to prepare an aerogel composition. Here, a planetary mixer (DN Tech, PT-005) was used for mixing.

[0129] The solids content of the produced aerogel composition was determined to be 50 wt% aerogel and 50 wt% polyvinyl alcohol.

[0130] 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 coated using a roll rolling method. 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.

[0131] Comparative Example 2 The manufacturing method was the same as in Example 1, except that silica fiber was used alone as the reinforcing material.

[0132] Comparative Example 3 The manufacturing method was the same as that of Example 1, except that glass wool was used alone as the reinforcing material.

[0133] Comparative Example 4 The same production method as in Example 1 was used except that glass chopped strands were used alone as the reinforcing material.

[0134] Comparative Example 5 The manufacturing method was the same as that of Example 1, except that glass felt was used alone as the reinforcing material.

[0135] (Experimental example) Experimental example 1: SEM analysis The cross sections of the aerogel layers of the battery insulation sheets of Examples 1, 4, and 7 and Comparative Example 1 were observed using a Hitachi S-4800 SEM, and the results are shown in Figures 3 to 6. Specifically, Figure 3 is an SEM image of Example 1, Figure 4 is that of Example 4, Figure 5 is that of Example 7, and Figure 6 is that of Comparative Example 1.

[0136] Specifically, in Comparative Example 1, no reinforcing material was present, whereas in Examples 1, 4, and 7, carbon fiber and glass wool were used in combination, and it was confirmed that the horizontal and vertical orientation of the reinforcing material was uniformly achieved.

[0137] Experimental example 2: Compression characteristic evaluation The heat insulating sheets produced in Examples 1 to 9 and Comparative Examples 1 to 5 were used to evaluate compression characteristics.

[0138] Specifically, using UTM equipment, each insulation sheet was sandwiched between 1mm thick aluminum plates, starting from the zero point, and the thickness change was measured when compressed from 0kN to 80kN at a compression speed of 0.02mm / sec. The compression rate was calculated by measuring the thickness reduction rate at 40kN based on the thickness of 5kN. The results are shown in Table 1 below.

[0139] Experimental example 3: Heat insulation evaluation The heat insulating sheets produced in Examples 1 to 9 and Comparative Examples 1 to 5 were used to evaluate heat insulating properties.

[0140] Specifically, each insulation sheet was placed between a pair of opposing 1 mm thick aluminum plates, then placed on a heat press, the upper plate of the heat press was heated to 350°C, and the lower plate of the heat press was not heated but maintained at the starting 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, as shown in Table 1 below.

[0141] [Table 1]

[0142] From Table 1, it was confirmed that in the examples, by including the first fibrous support and the second fibrous support at a certain ratio, the porosity and orientation were improved, and excellent compression properties were exhibited.

[0143] Here, from Examples 1 to 5, the evaluation results of the compression properties depending on the content ratio of the first fibrous support body and the second fibrous support body could be confirmed, and it was confirmed that better physical properties were exhibited when the first fibrous support body and the second fibrous support body were contained in a weight ratio of 1:1 to 1:4, particularly 1:3 to 1:4.

[0144] Furthermore, from Examples 1 and 6 to 8, the evaluation results of the compression properties depending on the combination of the first fibrous support and the second fibrous support were confirmed, and it was confirmed that better compression properties were exhibited when the first fibrous support was silica fiber and the second fibrous support was glass wool or ceramic wool.

[0145] Moreover, Example 9 is a case where a binder and a dispersant were used in combination during the production of the aerogel composition, and it was confirmed that the compression characteristics were further improved.

[0146] On the other hand, Comparative Example 1 did not contain any reinforcing material and showed a relatively high compression ratio, but had the problem of structural collapse due to the absence of an internal fibrous support.Furthermore, Comparative Examples 2 to 5 were cases in which a reinforcing material containing one type of fibrous support was used, and it was confirmed that the compression properties were lower than those of the Examples.

[0147] Furthermore, with regard to thermal insulation, the examples show that there is no temperature difference in the lower plate when different types of reinforcing materials are used in combination, which means that the combination of different types of reinforcing materials improves the compressibility, which is a mechanical property, without affecting thermal insulation.

[0148] On the other hand, it was confirmed that when the content of the first fibrous support increases beyond a certain ratio, the content of fibrous support with a relatively long length increases, and the thermal conductivity between the internal supports increases, which may result in a slight decrease in the insulating properties.

[0149] However, it can be confirmed that Example 1 has the same or better heat insulating performance than Comparative Examples 2 to 5, which used a single fibrous support, despite the use of different types of fibrous supports.

[0150] In particular, in Example 6, in which silica fiber, a support for improving mechanical compressibility, was used as the first fibrous support and ceramic wool, a support with excellent heat resistance, was used as the second fibrous support, it was confirmed that the insulation properties were significantly improved.

[0151] From this, it was confirmed that excellent physical properties are exhibited when the first fibrous support and the second fibrous support are contained in a weight ratio of 1:3 to 1:4, and when a fibrous support with excellent insulating properties is mixed.

[0152] Experimental Example 4: Fire resistance evaluation Of the heat insulating sheets manufactured in Examples 1 to 9 and Comparative Examples 1 to 5 above, fire resistance was evaluated using Examples 1 and 6, which had the same content ratio of the first fibrous support body and the second fibrous support body, i.e., 1:3.

[0153] Specifically, the heat insulating sheets were evaluated by observing changes such as the collapse of the internal structure after 10 minutes of irradiation using a gas ignition torch device at an irradiation temperature of 1100±10°C, with the flame being within a distance of 5 cm, and the fire resistance measurement photographs are shown in Figure 7. In Figure 7, the upper photograph shows the results of Example 1, and the lower photograph shows the results of Example 6.

[0154] Specifically, Example 1 is a case where silica fiber is used as the first fibrous support and glass wool is used as the second fibrous support, and Example 6 is a case where silica fiber is used as the first fibrous support and ceramic wool is used as the second fibrous support. As can be seen in Figure 1, Example 6, which uses ceramic wool with excellent insulating properties, has excellent fire resistance, and even after the fire resistance evaluation, it does not burn and the support layer is structurally firmly maintained, confirming that it also has excellent fire resistance.

[0155] Furthermore, in Example 6, by using a second fibrous support material with excellent insulating properties as one of the different reinforcing materials, the support layer remained firmly held even after the fire resistance evaluation, confirming that the material has excellent fire resistance.

[0156] Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made within the scope of the claims, the detailed description of the invention, and the accompanying drawings, and it is to be understood that these modifications also fall within the scope of the present invention. [Explanation of symbols]

[0157] 100 Battery Heat Insulation Sheet 110 First base material 120 aerogel layer 121 First fibrous support 122 Second fibrous support 130 Second base material 200 cells

Claims

1. a reinforcing material including a first fibrous support and a second fibrous support; Aerogel and a functional material comprising a binder or a combination of a binder and a dispersant; a solvent, the first fibrous support and the second fibrous support have different constituent components, the first fibrous support and the second fibrous support are contained in a weight ratio of 1:5 to 5:1; The average particle size (D 50 ) of the aerogel is 5 μm to 200 μm, The aerogel composition for a battery insulation sheet, wherein the binder comprises a water-based polymer binder.

2. the material of each of the first fibrous support and the second fibrous support is at least one selected from the group consisting of glass, silica, basalt, alumina, silicon carbide, boron, ceramic, and quartz; 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein each of the first fibrous support and the second fibrous support is in the form of at least one selected from the group consisting of powder, fiber, wool, chop, felt, batting, and lofty batting.

3. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the first fibrous support is silica fiber, and the second fibrous support is glass wool or silica wool.

4. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein each of the first fibrous support and the second fibrous support has an average length of 50 μm to 20,000 μm and an average diameter of 0.1 μm to 30 μm.

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 aqueous polymer binder is at least one selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

7. 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.

8. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the dispersant is at least one selected from the group consisting of surfactants and phosphate salts.

9. 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.

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

11. 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.

12. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the reinforcing material 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 a total solid content of the aerogel composition.

13. mixing a functional material, including a binder or a combination of a binder and a dispersant, 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 reinforcing material to produce an aerogel composition, the reinforcing material includes a first fibrous support and a second fibrous support, the first fibrous support and the second fibrous support have different constituent components, the first fibrous support and the second fibrous support are contained in a weight ratio of 1:5 to 5:1; The average particle size (D 50 ) of the aerogel is 5 μm to 200 μm, The method for producing an aerogel composition for a battery insulation sheet, wherein the binder comprises a water-based polymer binder.

14. A first substrate; A second substrate; an aerogel layer formed between the first substrate and the second substrate, A battery insulating sheet, wherein the aerogel layer is formed using the aerogel composition according to any one of claims 1 to 12.

15. The battery insulating sheet according to claim 14 , wherein each of the first substrate and the second substrate comprises a resin, a metal, an inorganic material other than a metal, or a composite of any of these.

16. 15. The battery insulation sheet according to claim 14, wherein within the aerogel layer, each of the first fibrous support and the second fibrous support has a vertical orientation, a horizontal orientation, or a combination thereof.

17. Applying the aerogel composition of any one of claims 1 to 12 onto a first substrate; and laminating a second substrate on the applied aerogel composition to produce a laminate.

18. The method for manufacturing a battery insulation sheet according to claim 17, further comprising a step of pressing and drying after the step of manufacturing the laminate.

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