Aerogel composition for battery heat insulating sheet, method for producing the same, battery heat insulating sheet formed using the same, and battery module including the same

Abstract

To provide an aerogel composition for battery thermal insulation sheets excellent in thermal insulation and fire resistance, a method of manufacturing the same, a battery thermal insulation sheet formed using the same, and a battery module including the same.SOLUTION: A battery thermal insulation sheet 100 has a structure comprising: 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. The first and second substrates are arranged to face cells adjacent thereto, respectively, and are formed from substances identical to or different from each other. An aerogel composition forming the aerogel layer contains, based on the total weight of solids in the aerogel composition, 55 wt.% to 75 wt.% of aerogel, 20 wt.% to 40 wt.% of a binder, and 0.1 wt.% to 8 wt.% of a phosphorus-based material.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an aerogel composition for a battery insulation sheet, a method for producing the same, a battery insulation sheet formed using the same, and a battery module including 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-ion 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 for a battery insulation sheet having excellent heat insulation and fire resistance, a method for manufacturing the same, a battery insulation sheet formed using the same, and a battery module including the same. [Means for solving the problem]

[0007] One embodiment provides an aerogel composition for a battery insulation sheet, including an aerogel, a functional material including a binder or the binder and a dispersant, a flame retardant including a phosphorus-based material, and a solvent.

[0008] The aerogel has a BET specific surface area of ​​500 m 2 / g~1,000m 2 / g.

[0009] The aerogel may be contained in an amount of 30% by weight to 90% by weight based on the total solid content of the aerogel composition.

[0010] The binder may include a water-based polymer binder.

[0011] The aqueous polymer binder may include at least one selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

[0012] When the functional material includes the dispersant, the dispersant may include one or more selected from the group consisting of surfactants and phosphate salts.

[0013] The functional substance may be contained in an amount of 5% by weight to 55% by weight based on the total solid content of the aerogel composition.

[0014] The phosphorus-based material may include at least one of phosphate-based ammonium salt, red phosphorus, and compounds represented by the following formulas (1) and (2).

[0015] [ka]

[0016] In formula (1), Ar 1 ~Ar 3 are each independently a substituted or unsubstituted C6 to C20 aryl group.

[0017] [ka]

[0018] In formula (2), Ar 4 ~Ar 10 are each independently a substituted or unsubstituted C6 to C20 aryl group.

[0019] The phosphate-based ammonium salt may include one or more selected from the group consisting of anhydrous ammonium phosphate, diammonium hydrogen phosphate, ammonium polyphosphate, and monoammonium phosphate.

[0020] The flame retardant may be contained in an amount of 0.01% by weight to 20% by weight based on the total solid content of the aerogel composition.

[0021] The flame retardant may be included in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the functional material.

[0022] The solvent may include one or more selected from the group consisting of polar solvents and non-polar solvents.

[0023] The weight ratio of the solvent to the total amount of solids in the aerogel composition may be 1:1 to 1:90.

[0024] The aerogel composition may contain 55% by weight to 75% by weight of the aerogel, 20% by weight to 40% by weight of the binder, and 0.1% by weight to 8% by weight of the phosphorus-based material, relative to the total solid content of the aerogel composition.

[0025] When the functional material includes the dispersant, the aerogel composition may include, relative to the total solid content of the aerogel composition, 55% by weight to 75% by weight of the aerogel, 20% by weight to 40% by weight of the binder, 0.1% by weight to 5% by weight of the dispersant, and 0.1% by weight to 8% by weight of the phosphorus-based material.

[0026] Another embodiment may provide a method for manufacturing an aerogel composition for a battery insulation sheet, the method including: mixing a solvent with a binder or a functional material including the binder and a dispersant, and a flame retardant including a phosphorus-based material to prepare a solvent mixture; and mixing the solvent mixture with an aerogel to prepare an aerogel composition.

[0027] Yet another embodiment may provide a battery insulation sheet including a first substrate, a second substrate, and an aerogel layer formed between the first substrate and the second substrate, wherein the aerogel layer is formed using the aerogel composition.

[0028] Yet another embodiment may provide a battery module including a plurality of cells and the battery insulation sheets respectively disposed between the plurality of cells, wherein the first substrate and the second substrate are each disposed to face an adjacent cell. [Effects of the Invention]

[0029] The battery insulation sheet according to an embodiment may have thermal insulation and fire resistance, and a battery module including the battery insulation sheet according to an embodiment may suppress the spread of heat and flames between adjacent cells due to thermal runaway of a cell. [Brief explanation of the drawings]

[0030] [Figure 1] 1 is a schematic diagram illustrating a 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. DETAILED DESCRIPTION OF THE INVENTION

[0031] The following detailed description of the embodiments will be made in order to enable those skilled in the art to easily implement the present invention, but the embodiments may be realized in various different forms and are not limited to the embodiments described herein.

[0032] Insulation is a material that prevents heat from moving from high temperature areas to low temperature areas, and is used in refrigerators, freezer warehouses, buildings, and various industrial sectors including the aircraft, electronics, and automotive industries.

[0033] 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.

[0034] Meanwhile, aerogel is a transparent or translucent cutting-edge material with a nanoporous structure. It has extremely low density and low thermal conductivity, and therefore has great potential as an insulating material. It is also considered a highly efficient super-insulating material that can be used in a variety of industrial fields.

[0035] 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.

[0036] According to one embodiment, the aerogel composition for a battery insulation sheet may include an aerogel, a functional material including a binder or a binder and a dispersant, a flame retardant including a phosphorus-based material, and a solvent.

[0037] A battery insulation sheet made from an aerogel composition comprising these components has excellent heat insulation and fire resistance, and can suppress the spread of heat and flames to adjacent cells due to thermal runaway of a cell.

[0038] In one embodiment, the aerogel has a BET specific surface area of ​​500 m 2 / g~1,000m 2 For example, the aerogel may have a BET specific surface area of ​​500 m 2 / g~950m 2 / g, 550m 2 / g~950m 2 / g, or 600m 2 / g~900m 2 By including an aerogel having a BET specific surface area within the above range, it is possible to provide a heat insulating sheet that can effectively prevent heat transfer and heat propagation between a plurality of cells.

[0039] The average particle size (D50) of the aerogel may be 5 μm to 200 μm, 10 μm to 100 μm, or 20 μm to 50 μm. By including aerogel having a particle size within the above range, the heat insulating properties can be improved and heat transfer between multiple cells can be delayed.

[0040] The average particle size (D50) can be measured, for example, using a laser diffraction method or a scanning electron microscope (SEM) photograph, and the average particle size (D50) of particles 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).

[0041] The aerogel content may be 30 to 90 wt %, 55 to 75 wt %, or 60 to 70 wt % based on the total solid content of the aerogel composition. By producing a battery insulation sheet using an aerogel composition containing aerogel within the above range, the heat insulating properties of the battery insulation sheet can be improved.

[0042] In one embodiment, the binder may include a water-based polymer binder, for example, the water-based polymer binder may include one or more selected from the group consisting of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

[0043] The water-soluble polymer may include, but is not limited to, one or more selected from the group consisting of polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinylpyrilidone.

[0044] The anionic water-soluble polymer may include at least one selected from the group consisting of polymers having functional groups of 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.

[0045] 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 may include, but are not limited to, at least one selected from the group consisting of polyethylene amine and polyamine.

[0046] 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.

[0047] The binder may include a water-based polymer and a water-dispersible polymer, for example, a water-based polymer having binder and dispersing properties, and a water-dispersible polyurethane having fire-resistant properties, and a specific example thereof may include polyvinyl alcohol and a water-dispersible polyurethane.

[0048] 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 mixing the aqueous polymer and the water-dispersible polymer in a weight ratio within the above range, the heat insulation properties, dust resistance, and compressibility of the heat insulating sheet can be improved, as well as the fire resistance and mechanical properties.

[0049] The binder content may be 5 to 55 wt%, 20 to 40 wt%, or 25 to 35 wt%, based on the total solid content of the aerogel composition. By producing a battery insulation sheet using an aerogel composition containing a binder within the above range, the durability and dust resistance of the battery insulation sheet can be improved.

[0050] In one embodiment, the dispersant may include at least one selected from the group consisting of surfactants and phosphate salts. Specific examples of the dispersant include, but are not limited to, at least one of nonionic surfactants, anionic surfactants, amphoteric surfactants, natural surfactants such as lecithin, and phosphate salts.

[0051] When a dispersant is further contained, the dispersion of the aerogel in the composition is further improved, the aerogel is dispersed uniformly, and the heat insulating properties can be improved.

[0052] 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. By including a dispersant within the above range, the aerogel composition can be produced at low cost, and a battery insulation sheet having excellent heat insulation properties, durability, and dust resistance can be produced using this.

[0053] 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. Mixing the binder and dispersant in a weight ratio within the above ranges may allow the aerogel to be more uniformly dispersed in the aerogel layer.

[0054] The functional substance may be contained in an amount of 5 to 55% by weight, 15 to 50% by weight, or 20 to 40% by weight relative to the total solid content of the aerogel composition.

[0055] In one embodiment, the phosphorus-based material can include any material that has flame retardant properties and contains phosphorus.

[0056] The phosphorus-based substance may include, for example, one or more of phosphate-based ammonium salts, red phosphorus, and compounds represented by the following formulas (1) and (2).

[0057] The phosphate-based ammonium salt may include one or more selected from the group consisting of anhydrous ammonium phosphate, diammonium hydrogen phosphate, ammonium polyphosphate, and monoammonium phosphate. As a specific example, the phosphorus-based material may include anhydrous ammonium phosphate. When the phosphate-based ammonium salt is included, char is formed by phosphorylation when the ambient temperature increases due to thermal runaway of the cell, thereby blocking the transfer of heat to other cells.

[0058] Any commercially available red phosphorus can be used as a flame retardant. For example, red phosphorus is an allotrope of elemental phosphorus (P) and is obtained as a reddish-purple amorphous powder.

[0059] The red phosphorus may be microencapsulated in a polymer such as a phenol-formaldehyde resin. Microencapsulation can prevent direct contact between the red phosphorus and external components when the red phosphorus is stored together with one of the catalyst components, thereby extending the storage time. Microencapsulated red phosphorus can be prevented from being hydrolyzed to unstable volatile compounds such as phosphine.

[0060] [ka]

[0061] In formula (1), Ar 1 ~Ar 3 are each independently a substituted or unsubstituted C6 to C20 aryl group. For example, Ar 1 ~Ar 3 are each independently a substituted or unsubstituted C6 to C18 aryl group or a C6 to C12 aryl group.

[0062] [ka]

[0063] In formula (2), Ar 4 ~Ar 10 are each independently a substituted or unsubstituted C6 to C20 aryl group. For example, Ar 4 ~Ar 10 are each independently a substituted or unsubstituted C6 to C18 aryl group or a C6 to C12 aryl group.

[0064] The phosphorus-based materials represented by Formula 1 and Formula 2 above form polyphosphoric acid when the ambient temperature increases, and the polyphosphoric acid forms a carbon layer through esterification and dehydrogenation reactions. The carbon layer thus formed can provide flame retardancy by blocking oxygen and latent heat.

[0065] For purposes of this invention, an "aryl group" is defined as a monovalent substituent derived from an aromatic hydrocarbon.

[0066] Specific examples of the aryl group include a phenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a naphthacenyl group, a tolyl group, a biphenylyl group, a terphenylyl group, a fluoranthenyl group, a fluorenyl group, a perylenyl group, an indenyl group, an azulenyl group, a heptalenyl group, a phenalenyl group, and a phenanthrenyl group.

[0067] In the above formula 1 and formula 2, Ar 1 ~Ar 10 may each be substituted or unsubstituted with an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogen group, a cyano group, or a trimethylsilyl group.

[0068] In the present invention, the term "C#", where "#" is a positive integer, refers to any hydrocarbon having # carbon atoms. Thus, the term "C6" refers to a hydrocarbon compound having 6 carbon atoms, and the term "C20" refers to a hydrocarbon compound having 20 carbon atoms.

[0069] The flame retardant may be contained in an amount of 0.01 to 20 wt%, 0.1 to 10 wt%, or 0.25 to 5 wt%, based on the total solid content of the aerogel composition. When the phosphorus-based substance is contained within the above range, the heat insulating properties of the heat insulating sheet are improved, as well as the fire resistance, and heat transfer between cells can be blocked.

[0070] The flame retardant may be included in an amount of 0.1 to 20 parts by weight, 0.5 to 17 parts by weight, or 1 to 10 parts by weight per 100 parts by weight of the functional material. If the content of the phosphorus-based material relative to the content of the functional material is controlled within this range, char is formed when the heat insulating sheet is exposed to a high-temperature environment, and this char can act as a flame shield, resulting in excellent fire resistance of the heat insulating sheet and the ability to block the spread of heat and flames to adjacent cells due to thermal runaway of the cells.

[0071] In one embodiment, the solvent may include one or more selected from the group consisting of polar solvents and non-polar solvents.

[0072] The polar solvent may include water, an alcohol-based solvent, or a combination thereof.

[0073] The water may include, for example, purified water, deionized water, or a combination thereof.

[0074] 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.

[0075] 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 is preferably, but not limited to, an alkane solvent such as hexane, or a mixture containing an alkane solvent.

[0076] The solvent may include water. Using water as a solvent can effectively reduce raw material costs and post-processing costs. However, when water is used as a solvent, it can be difficult to mix with hydrophobic aerogel. In one embodiment, however, the aerogel is uniformly dispersed by controlling the mixing step design, mixing conditions, and the addition and amounts of binder and dispersant. Uniform dispersion of the aerogel in the composition in this manner allows for the formation of a thin battery insulation sheet with excellent insulation properties, durability, and low dusting, even without using a large amount of binder.

[0077] The solvent may be contained in such a way that the weight ratio of the solvent to the total solid content of the aerogel composition is 1:1 to 1:90. For example, the weight ratio of the solvent to the total solid content of the aerogel composition may be 1:50 to 1:70, 1:20 to 1:30, or 1:2 to 1:10. By controlling the weight ratio of the solvent to the total solid content within the above range, the viscosity can be controlled and an aerogel layer can be coated.

[0078] In one embodiment, the aerogel composition may contain 55% to 75% by weight of aerogel, 20% to 40% by weight of binder, and 0.1% to 8% by weight of phosphorus-based material, based on the total solid content of the aerogel composition.

[0079] As a specific example, the aerogel composition may contain 60 to 70% by weight of aerogel, 25 to 35% by weight of binder, and 0.25 to 5% by weight of phosphorus-based material, based on the total solid content of the aerogel composition. When the aerogel composition is formed within these ranges, excellent heat insulation properties can be achieved, and at the same time, fire resistance can be improved, thereby blocking heat transfer between cells.

[0080] In one embodiment, when the functional material includes a dispersant, the aerogel may be contained in an amount of 55% to 75% by weight, the binder in an amount of 20% to 40% by weight, the dispersant in an amount of 0.1% to 5% by weight, and the phosphorus-based material in an amount of 0.1% to 8% by weight, based on the total solid content of the aerogel composition.

[0081] For example, when the functional material contains a dispersant, the aerogel composition may contain 60 to 70% by weight of aerogel, 25 to 35% by weight of binder, 0.1 to 3% by weight of dispersant, and 0.25 to 5% by weight of phosphorus-based material, based on the total solid content of the aerogel composition. By configuring the aerogel composition within these ranges, the dispersibility of the aerogel can be improved, achieving excellent heat insulation and improving fire resistance, thereby more effectively blocking heat transfer between cells.

[0082] In one embodiment, the aerogel composition may further include a silane-based compound. The silane-based compound may include, for example, one or more compounds 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.

[0083] 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.

[0084] According to one embodiment, a method for manufacturing an aerogel composition may include mixing a functional material including a binder or a binder and a dispersant, and a flame retardant including a phosphorus-based material with a solvent to prepare a solvent mixture, and mixing the solvent mixture with an aerogel to prepare an aerogel composition.

[0085] In the step of preparing a solvent mixture by mixing a functional material and a flame retardant into a solvent, a binder may be mixed as the functional material into the solvent, or a binder and a dispersant may be mixed into the solvent. Here, the specific description of the solvent, binder, dispersant, and phosphorus-based material may be as described above.

[0086] In the step of preparing the aerogel composition by mixing the solvent mixture and the aerogel, the aerogel may be added in a powder form, and the specific description regarding the aerogel may be the same as that described above.

[0087] In each of the steps of preparing a solvent mixture by mixing a functional material including a binder or a binder and a dispersant, and a flame retardant including a phosphate-based material with a solvent, and preparing an aerogel composition by mixing the solvent mixture with an aerogel, 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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).

[0092] 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.

[0093] 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.

[0094] When the functional material 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. By mixing the solvent and functional material as described above, a solvent mixture in which the binder or the binder and dispersant are uniformly dispersed is produced, making it easier to mix the aerogel in the subsequent step.

[0095] 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. When the aerogel is added to the solvent mixture and mixed as described above, it is possible to prevent the aerogel from agglomerating with each other and induce uniform dispersion.

[0096] A battery insulation sheet according to one embodiment 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 described above.

[0097] FIG. 1 is a schematic diagram showing the structure of a battery insulation sheet according to one embodiment.

[0098] 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. Here, the first substrate and the second substrate may be disposed to face the adjacent cell, respectively. In this case, the first substrate and the second substrate may be formed of the same or different materials.

[0099] By forming an aerogel layer using the aerogel composition according to one embodiment between the first substrate and the second substrate, the battery insulation sheet has improved durability as well as thermal insulation properties, and can block heat transfer between cells due to its excellent fire resistance.

[0100] In the battery insulating sheet, the specific description of the aerogel composition forming the aerogel layer can be as described above.

[0101] The first substrate and the second substrate may be made of various materials, such as resin, metal, inorganic material other than metal, or a composite thereof, and are not limited to a specific type. The form of the substrate may be a film, thin film, sheet, or the like, and is not particularly limited to a specific type.

[0102] The resin may include, for example, one or more selected from the group consisting of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0103] The metal may include, for example, one or more selected from the group consisting of copper, nickel, cobalt, iron, chromium, vanadium, palladium, ruthenium, rhodium, molybdenum, tungsten, iridium, silver, gold, and platinum. When a metal substrate is used, the substrate may be subjected to corrosion prevention treatment, insulation treatment, etc., as necessary.

[0104] The inorganic material may include one or more selected from the group consisting of calcium carbonate (CaCO3), talc, and mica.

[0105] As a specific example, each of the first substrate and the second substrate may include an inorganic material, and more specifically, may include mica, which can improve the thermal insulation properties and durability of the heat insulating sheet.

[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] In one embodiment, a method for manufacturing a battery insulation sheet may include applying an aerogel composition to a first substrate, laminating a second substrate on the applied aerogel composition to manufacture a laminate, pressing the laminate, and drying the laminate.

[0108] In the method for manufacturing a battery insulation sheet, the specific description of the first substrate and the second substrate may be as described above.

[0109] In the step of applying the aerogel composition onto the first substrate, the aerogel composition can be applied directly onto the first substrate.

[0110] The step of applying the aerogel composition onto the first substrate may be carried out in the same manner as applying a slurry onto a conventional substrate.

[0111] The step of applying the aerogel composition onto the first substrate may be repeated one or more times.

[0112] In one embodiment, an aerogel composition is applied to a first substrate, and a second substrate is then laminated on the applied aerogel composition to form a structure in which the first substrate, the aerogel layer, and the second substrate are laminated in sequence.

[0113] In one embodiment, the step of pressing the laminate may be carried out by a conventional pressing method.

[0114] In one embodiment, in the step of drying the laminate, the drying may be performed at a temperature of, for example, 25° C. to 100° C., 45° C. to 90° C., or 60° C. to 85° C. By drying under the above-mentioned temperature conditions, it is possible to form a robust aerogel layer on the substrate without using a separate adhesive member or adhesive, while preventing detachment of the aerogel layer from the substrate.

[0115] In one embodiment, the steps of pressing the laminate and drying the laminate may be performed in separate steps or may be performed simultaneously.

[0116] A battery module according to one embodiment includes a plurality of cells and battery insulation sheets respectively provided between the plurality of cells, and the first substrate and the second substrate may each be arranged to face an adjacent cell.

[0117] FIG. 2 is a schematic diagram showing a battery insulation sheet according to an embodiment formed between a plurality of cells.

[0118] 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, one side of the battery insulation sheet on which the first substrate is formed and the other side on which the second substrate is formed may be disposed to face each of the adjacent cells. By forming the battery insulation sheet 100 according to an embodiment between each of the plurality of cells 200, it is possible to first block a flame inside the cell and minimize the spread of the flame to other cells, thereby providing a battery module and a battery pack including the same with improved safety. [Example]

[0119] 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.

[0120] (battery insulation sheet manufacturing) Example 1 1. Aerogel Composition Preparation Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder and anhydrous ammonium phosphate (Sigma Aldrich, 7722-76-1) as a phosphorus-based substance were added to ultrapure water as a solvent, and mixed under conditions of an open blade of 30 rpm and a Despa blade of 700 rpm to produce a solvent mixture. 2 The aerogel composition was prepared by adding aerogel (1 / g) and mixing under the conditions of an open blade 70 rpm and a Desper blade 1500 rpm. Here, a planetary mixer (DN Tech, PT-005) was used for mixing.

[0121] The solids content of the prepared aerogel composition was confirmed to be 69.75 wt% aerogel, 30 wt% polyvinyl alcohol, and 0.25 wt% anhydrous ammonium phosphate.

[0122] 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.

[0123] Example 2 The same method as in Example 1 was used to prepare the aerogel composition, except that the amounts of raw materials added were adjusted to prepare an aerogel composition with a solid content of 69.5 wt % aerogel, 30 wt % polyvinyl alcohol, and 0.5 wt % anhydrous ammonium phosphate.

[0124] Example 3 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added during the preparation of the aerogel composition were adjusted to prepare an aerogel composition with a solid content of 67.5 wt % aerogel, 30 wt % polyvinyl alcohol, and 2.5 wt % anhydrous ammonium phosphate.

[0125] Example 4 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added during the preparation of the aerogel composition were adjusted to prepare an aerogel composition with a solid content of 65 wt % aerogel, 30 wt % polyvinyl alcohol, and 5 wt % anhydrous ammonium phosphate.

[0126] Example 5 The same method as in Example 1 was used to prepare the aerogel composition, except that the amounts of raw materials added were adjusted to prepare an aerogel composition with a solid content of 69.95 wt % aerogel, 30 wt % polyvinyl alcohol, and 0.05 wt % anhydrous ammonium phosphate.

[0127] Example 6 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added during the preparation of the aerogel composition were adjusted to prepare an aerogel composition with a solid content of 60 wt % aerogel, 30 wt % polyvinyl alcohol, and 10 wt % anhydrous ammonium phosphate.

[0128] Example 7 The same method as in Example 1 was used to prepare the phosphorus-based material, except that diammonium hydrogen phosphate (ammonium phosphate dibasic) was used instead of anhydrous ammonium phosphate. Example 8 The same production method as in Example 1 was used, except that triphenyl phosphate was used instead of anhydrous ammonium phosphate as the phosphorus-based substance.

[0129] Example 9 1. Aerogel Composition Preparation Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder, surfactant (Triton-X100, Sigma Aldrich) as a dispersant, and anhydrous ammonium phosphate (Sigma Aldrich, 7722-76-1) as a phosphorus-based material were added to ultrapure water as a solvent, and then mixed under conditions of an open blade of 30 rpm and a despa blade of 700 rpm to produce a solvent mixture. The solvent mixture then had a BET value of 800m 2The aerogel composition was prepared by adding aerogel (1 / g) and mixing under the conditions of an open blade of 70 rpm and a Desper blade of 1500 rpm. Here, a planetary mixer (DN Tech, PT-005) was used for mixing.

[0130] The solids content of the produced aerogel composition was determined to be 69.75 wt % aerogel, 29.5 wt % polyvinyl alcohol, 0.5 wt % dispersant, and 0.25 wt % anhydrous ammonium phosphate.

[0131] 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.

[0132] Comparative Example 1 The aerogel composition was prepared in the same manner as in Example 1, except that the amounts of raw materials added during the preparation of the aerogel composition were adjusted to prepare an aerogel composition with a solid content of 70 wt % aerogel and 30 wt % polyvinyl alcohol.

[0133] (Experimental example) Experimental example 1: Heat insulation evaluation The heat insulating sheets produced in Examples 1 to 9 and Comparative Example 1 were used to evaluate the heat insulating properties. Specifically, each heat insulating sheet was placed between a pair of opposing 1 mm thick aluminum plates, which were then placed on a heat press. The upper plate of the heat press was heated to 350°C, while the lower plate of the heat press was not heated and maintained at 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.

[0134] Experimental Example 2: Burn Through Resistance The heat insulating sheets manufactured in Examples 1 to 9 and Comparative Example 1 were used to evaluate the burn-through resistance.

[0135] Specifically, the insulation sheet is 5 x 8 cm 2 After preparation as described above, a flame was applied to the heat insulating sheet at a distance of about 5 cm from the sheet using a gas torch, and the time taken for the heat insulating sheet on the opposite side to break was measured to confirm the fire resistance.

[0136] [Table 1]

[0137] Referring to Table 1 above, it was confirmed that all of Examples 1 to 9 had excellent thermal insulation properties. Examples 1 to 6 confirmed that the fire resistance varied depending on the component content of the aerogel composition, and that when the flame retardant was contained in an amount of 0.5 to 10 parts by weight per 100 parts by weight of the total binder, the fire resistance was extremely excellent. Specifically, in Example 5, it was confirmed that the fire resistance was somewhat reduced due to the low content of the flame retardant containing a phosphorus-based substance. Furthermore, in Example 6, it was confirmed that the heat insulation properties were somewhat reduced due to the high content of the flame retardant containing a phosphorus-based substance. Furthermore, Examples 1, 7, and 8 confirmed the physical properties depending on the type of flame retardant, and as a result, it was confirmed that the heat insulation properties and fire resistance were improved when a flame retardant containing a phosphorus-based substance was used. Furthermore, in Example 9, where a binder and a dispersant were mixed, it was confirmed that the heat insulation properties and fire resistance were further improved.

[0138] On the other hand, in Comparative Example 1, which did not contain a flame retardant containing a phosphorus-based substance, it was confirmed that the heat insulating properties were significantly reduced.

[0139] Therefore, it was confirmed that the aerogel composition according to one embodiment has excellent heat insulating properties and heat propagation blocking properties.

[0140] 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]

[0141] 100 Battery Heat Insulation Sheet 110 First base material 120 aerogel layer 130 Second base material 200 cells

Claims

1. Aerogel and a functional material containing a binder or the binder and a dispersant; a flame retardant containing a phosphorus-based substance; and a solvent.

2. 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.

3. The aerogel, the functional material, and the flame retardant are contained as solid components of the aerogel composition for battery insulation sheets, 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the content of the aerogel is 30 wt % to 90 wt % based on the total solid content of the aerogel composition for a battery insulation sheet.

4. The aerogel composition for a battery insulation sheet according to claim 1 , wherein the binder comprises a water-based polymer binder.

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

6. The aerogel, the functional material, and the flame retardant are contained as solid components of the aerogel composition for battery insulation sheets, 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the content of the functional material is 5 wt % to 55 wt % based on the total solid content of the aerogel composition for a battery insulation sheet.

7. 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the phosphorus-based material comprises at least one of a phosphate-based ammonium salt, red phosphorus, and a compound represented by the following formula (1) or formula (2): 【Chemical 1】 In formula (1), Ar １ ~Ar ３ are each independently substituted or unsubstituted C ６ ~C ２０ is an aryl group, 【Chemistry 2】 In formula (2), Ar ４ ~Ar １０ are each independently substituted or unsubstituted C ６ ~C ２０ It is an aryl group.

8. 8. The aerogel composition for a battery insulation sheet according to claim 7, wherein the phosphate-based ammonium salt comprises at least one selected from the group consisting of anhydrous ammonium phosphate, diammonium hydrogen phosphate, ammonium polyphosphate, and monoammonium phosphate.

9. The aerogel, the functional material, and the flame retardant are contained as solid components of the aerogel composition for battery insulation sheets, 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the content of the flame retardant is 0.01 wt % to 20 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 content of the flame retardant is 0.1 to 20 parts by weight, based on 100 parts by weight of the functional material.

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

12. 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.

13. The aerogel, the functional material, and the flame retardant are contained as solid components of the aerogel composition for battery insulation sheets, 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein, based on a total solid content of the aerogel composition for a battery insulation sheet, the content of the aerogel is 55 wt % to 75 wt %, the content of the binder is 20 wt % to 40 wt %, and the content of the phosphorus-based material is 0.1 wt % to 8 wt %.

14. The aerogel, the functional material, and the flame retardant are contained as solid components of the aerogel composition for battery insulation sheets, When the functional substance contains the dispersant, 2. The aerogel composition for a battery insulation sheet according to claim 1, wherein the aerogel content is 55 wt % to 75 wt %, the binder content is 20 wt % to 40 wt %, the dispersant content is 0.1 wt % to 5 wt %, and the phosphorus-based material content is 0.1 wt % to 8 wt %, relative to a total solid content of the aerogel composition for a battery insulation sheet.

15. preparing a solvent mixture by mixing a binder or a functional material including the binder and a dispersant, and a flame retardant including a phosphorus-based material into a solvent; and mixing the solvent mixture and an aerogel to prepare an aerogel composition.

16. A first substrate; A second substrate; an aerogel layer formed between the first substrate and the second substrate, The aerogel layer is formed using the aerogel composition for battery insulation sheets according to any one of claims 1 to 14.

17. A plurality of cells; The battery insulating sheet according to claim 16 is disposed between the plurality of cells, The first substrate and the second substrate are each arranged to face an adjacent cell.

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