Aerogel composition for battery insulation sheet, method for manufacturing aerogel composition for battery insulation sheet, battery insulation sheet, and method for manufacturing battery insulation sheet

Abstract

The invention relates to an aerogel composition for a battery insulation sheet, a method for manufacturing the aerogel composition for the battery insulation sheet, the battery insulation sheet, and a method for manufacturing the battery insulation sheet. Example embodiments include an aerogel composition for a battery insulation sheet, the aerogel composition including: a reinforcing material including a first fibrous support and a second fibrous support; an aerogel; the functional material comprises a binding agent, a dispersing agent or a combination of the binding agent and the dispersing agent; and a solvent, wherein the first fibrous support and the second fibrous support have different compositions. Example embodiments also include a method of manufacturing the aerogel composition, a battery insulating sheet formed using the aerogel composition, and a method of manufacturing a battery insulating sheet.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0098056 filed on July 27, 2023 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] Example embodiments relate to an aerogel composition for a battery insulating sheet, a method of manufacturing the aerogel composition for a battery insulating sheet, a battery insulating sheet formed using the aerogel composition, and a method of manufacturing the battery insulating sheet. Background Art

[0004] A secondary battery is or includes a power storage system that converts electrical energy into chemical energy, stores chemical energy, and provides a high energy density. Compared to primary batteries, which are usually non-rechargeable, secondary batteries are rechargeable and are widely used in information technology (IT) devices (such as, for example, smart phones, mobile phones, laptops, tablet computers, etc.). People are increasingly interested in electric vehicles to reduce or prevent environmental pollution, and high-capacity secondary batteries can be used in electric vehicles. Secondary batteries can exhibit characteristics such as, for example, high density, high output, and stability.

[0005] When multiple high-capacity battery cells are included, such as in a lithium secondary battery, one battery cell may overheat and may enter thermal runaway for various reasons, which may adversely affect other battery cells adjacent thereto, so it may be desirable to thermally isolate adjacent battery cells from each other.

[0006] Conventionally, a plate or an insulating resin sheet is disposed between the battery cells to isolate and insulate adjacent battery cells from each other. Summary of the invention

[0007] Example embodiments include aerogel compositions having desired, advantageous or improved thermal insulation, fire resistance, mechanical properties and dustiness, methods of making aerogel compositions, battery insulation sheets formed using the aerogel compositions, and methods of making battery insulation sheets.

[0008] Example embodiments include an aerogel composition for a battery insulating sheet, the aerogel composition including: a reinforcing material including a first fiber support and a second fiber support; an aerogel; a functional material including a binder, a dispersant, or a combination thereof; and a solvent. The first fiber support and the second fiber support have different compositions.

[0009] Each or at least one of the first fiber support and the second fiber support may be made of or include at least one of glass, silica, rock, basalt, alumina, silicon carbide, boron, ceramics, and quartz. Each or at least one of the first fiber support and the second fiber support may be in the form of at least one of fiber, powder, wool, chopped strands (which also includes chopped strands), felt, and wadding (e.g., fluffy wadding).

[0010] The first fibrous support may be or include silica fibers or glass fiber chopped strands, and the second fibrous support may be or include glass wool, quartz wool, or ceramic wool.

[0011] The first fibrous support and the second fibrous support may be included in a weight ratio of about 1:5 to 5:1.

[0012] Each or at least one of the first fibrous support and the second fibrous support may have an average length of about 50 μm to 20,000 μm and an average diameter of about 0.1 μm to 30 μm.

[0013] Aerogels can have a diameter of about 500 m 2 / g~1,000m 2 / g Brunauer, Emmet and Teller (BET) specific surface area.

[0014] The aerogel may have an average particle size (D50) of about 5 μm to 200 μm.

[0015] The binder may include an aqueous polymer binder, and the aqueous polymer binder may be or include at least one of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

[0016] The binder may be included in an amount of 0.5 wt % to 20 wt % based on the total amount of solids in the aerogel composition.

[0017] The dispersant may be at least one of a surfactant and a phosphate salt.

[0018] The dispersant may be included in an amount of about 0.1 wt % to about 6 wt % based on the total amount of solids in the aerogel composition.

[0019] The solvent may be at least one of a polar solvent and a non-polar solvent.

[0020] The weight ratio of the solvent to the total amount of solids in the aerogel composition may be about 1:1 to 1:90.

[0021] Based on the total amount of solids in the aerogel composition, the reinforcing material may be included at about 5 wt % to 70 wt %, the aerogel may be included at about 10 wt % to 90 wt %, and the functional material may be included at about 0.5 wt % to 20 wt %.

[0022] Another example embodiment includes a method for manufacturing an aerogel composition for a battery insulating sheet, the method including mixing a solvent with a functional material including a binder, a dispersant or a combination thereof to make a solvent mixture, mixing the solvent mixture with an aerogel to make an aerogel mixture, and mixing the aerogel mixture with a reinforcing material to make an aerogel composition. The reinforcing material may include a first fiber support and a second fiber support, and the first fiber support and the second fiber support may have different components. When the first fiber support and the second fiber support have different components, some components may be the same but some components may be different, or the components in the first fiber support and the second fiber support may be completely different. For example, the first fiber support may include at least one component that is different from the second fiber support.

[0023] Another example embodiment includes a battery insulating 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 above-described aerogel composition.

[0024] Each or at least one of the first substrate and the second substrate may include a resin, a metal, an inorganic material other than a metal, or a mixture thereof.

[0025] Each or at least one of the first and second fibrous supports in the aerogel layer may have a vertical orientation, a horizontal orientation, or a combination thereof.

[0026] Another example embodiment includes a method of manufacturing a battery insulating sheet, the method including applying the above-described aerogel composition to a first substrate and laminating a second substrate on the applied aerogel composition to manufacture a laminate.

[0027] The method may further include pressing and drying the laminate after manufacturing the laminate. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The attached drawings incorporated in this specification illustrate example embodiments and are used to further illustrate the technical concept of the present disclosure in conjunction with the detailed description of the following example embodiments, and the present disclosure is not to be construed as being limited to the contents shown in these drawings. In the drawings:

[0029] Figure 1 is a schematic diagram showing the structure of a battery insulation sheet according to an example embodiment;

[0030] Figure 2 is a schematic diagram showing a battery insulation sheet according to an example embodiment formed between a plurality of battery cells;

[0031] Figure 3 is a SEM image of the aerogel layer of the battery insulation sheet according to Example 1;

[0032] Figure 4 is a SEM image of an aerogel layer of a battery insulating sheet according to Example 4;

[0033] Figure 5 is a SEM image of the aerogel layer of the battery insulating sheet according to Example 7; and

[0034] Figure 6 The SEM image of the aerogel layer of the battery insulation sheet according to Comparative Example 1 is DETAILED DESCRIPTION

[0035] Hereinafter, example embodiments will be described in detail so that those skilled in the art can easily implement the example embodiments. However, example embodiments may be implemented in different forms and are not limited to the example embodiments described herein.

[0036] When the term "about" or "substantially" is used in conjunction with a numerical value in this specification, it is intended that the associated numerical value includes a tolerance of ±10% around the stated numerical value. When a range is specified, the range includes all values ​​therebetween, such as increments of 0.1%.

[0037] Insulation materials, which hinder or prevent the flow of heat from a higher temperature to a lower temperature, are used not only in refrigerators, cold storages, and buildings, but also in various other industries (including the aviation, electronics, and automobile industries).

[0038] Insulating materials may have desirable, advantageous, or improved thermal insulation properties (also referred to as "thermal insulation") through low thermal conductivity and mechanical strength to maintain the thermal insulation properties over time.

[0039] Aerogels may be transparent or translucent advanced materials with a nanoporous structure, exhibiting substantially low density and low thermal conductivity, so aerogels have high potential as insulating materials and may be considered as highly efficient super insulating materials that can be used in various industrial applications.

[0040] The advantages of aerogels are that aerogels have lower thermal conductivity than conventional organic insulating materials (such as, for example, polystyrene foam), and aerogels can address key weaknesses of organic insulating materials (such as, for example, fire vulnerability and generation of harmful gases during fire).

[0041] However, in general, aerogels can be brittle, easily broken upon slight impact, and difficult to process into small thicknesses and shapes, making it difficult to manufacture insulating materials using only aerogels despite having desirable, advantageous, or improved thermal insulation.

[0042] An aerogel composition according to example embodiments may include: a reinforcing material including a first fiber support and a second fiber support; an aerogel; a functional material including a binder, a dispersant, or a combination thereof; and a solvent, wherein the first fiber support and the second fiber support may have different compositions.

[0043] The battery insulating sheet manufactured using the aerogel composition including the above components can have desired, favorable or improved thermal insulation, fire resistance and mechanical properties, can have a low manufacturing process cost, and can also reduce or prevent the generation of dust from the aerogel during the manufacturing process and in actual use, thereby improving the safety of the battery.

[0044] In example embodiments, the reinforcement material may include a first fiber support and a second fiber support having different compositions, thereby improving mechanical properties of a battery insulation sheet formed using the reinforcement material.

[0045] Each or at least one of the first fiber support and the second fiber support may include fibers used as a support for a common insulating material. Hereinafter, without mentioning "first" or "second", the fiber support may refer to each of the first fiber support and the second fiber support.

[0046] The fibrous support may be or include at least one of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers.

[0047] The natural fiber may be or include, for example, at least one of hemp, jute, flax, coir, kenaf, and cellulose.

[0048] The ceramic fiber may be or include at least one of silicon carbide, silicon nitride, boron nitride, and aluminum silicon carbide.

[0049] The mineral fiber may be or include, for example, at least one of basalt, diatomaceous earth, alumina, boron, quartz, silica, slag, and rock.

[0050] The polymer fiber may be or include, for example, at least one of nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamideimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyethylene (PE) and polypropylene (PP). As an example, the polymer fiber may include, but is not limited to, at least one of polyimide, polyamide and polybenzimidazole.

[0051] The fibrous support may be in the form of, for example, but not limited to, at least one of fibers, powder, cotton, chopped strands, felt, and batting (eg, fluffy batting).

[0052] Each or at least one of the first fiber support and the second fiber support may be made of or include at least one of glass, silica, rock, basalt, alumina, silicon carbide, boron, ceramics, and quartz. Each or at least one of the first fiber support and the second fiber support may be in the form of at least one of fiber, powder, cotton, chopped strands, felt, and wadding (e.g., fluffy wadding). As an example, the first fiber support may be or include silica fiber or glass fiber chopped strands, and the second fiber support may be or include glass wool or quartz wool. As another example, the first fiber support may be or include silica fiber, and the second fiber support may be or include glass wool, quartz wool, or ceramic wool. When different types of first and second fiber supports as described above are included, the mechanical properties of the battery insulating sheet may be further improved.

[0053] The first fiber support and the second fiber support may be included in a weight ratio of about 1:5 to 5:1, about 1:4 to 4:1, or about 1:3 to 3:1. When the first fiber support and the second fiber support are included in a weight ratio within any one of the above ranges, the mechanical properties of the battery insulating sheet may be further improved.

[0054] The average length of the fiber support may be, for example, about 50 μm to 20,000 μm, about 100 μm to 12,000 μm, about 100 μm to 5,000 μm, or about 3,000 μm to 12,000 μm. The average length of the fiber support may refer to the average length of each of the first fiber support and the second fiber support. By including a fiber support having an average length within any one of the above ranges, an aerogel layer can be firmly formed and its mechanical properties can be improved.

[0055] The average diameter of the fiber support may be, for example, about 0.1 μm to 30 μm, about 8 μm to 20 μm, about 8 μm to 12 μm, or about 10 μm to 20 μm. The average diameter of the fiber support may refer to the average diameter of each of the first fiber support and the second fiber support. By including a fiber support having an average diameter within any one of the above ranges, the structure of the aerogel layer can be ensured and the manufacturing cost can be reduced.

[0056] The first fiber support may have an average diameter of about 8 μm to 12 μm and an average length of about 100 μm to 20,000 μm, and the second fiber support may have an average diameter of about 10 μm to 20 μm and an average length of about 3 μm to 12 μm. By including the first fiber support and the second fiber support, each having an average diameter and an average length within the above range, the porosity and orientation can be improved, thereby improving the compressibility.

[0057] As used herein, the term "average diameter" refers to the average circular diameter when the cross-section of the material is circular, and refers to the average major axis length when the cross-section of the material is non-circular.

[0058] Based on the total amount of solids in the aerogel composition, the content of the reinforcing material may be about 5 wt% to 70 wt%, about 25 wt% to 60 wt%, or about 30 wt% to 50 wt%. When the aerogel composition including the reinforcing material within the above range is used to manufacture a battery insulating sheet, the mechanical properties of the battery insulating sheet can be improved.

[0059] In an example embodiment, the aerogel may have a diameter of about 500 m 2 / g~1,000m 2 / g BET specific surface area. For example, the aerogel may have a BET specific surface area of ​​about 500 m 2 / g~950m 2 / g, about 550m 2 / g~950m 2 / g or about 600m 2 / g~900m 2 Because the aerogel having a BET specific surface area within the above range is included, a battery insulating sheet capable of effectively reducing or preventing heat transfer and heat propagation between a plurality of battery cells can be provided.

[0060] The average particle size (D50) of the aerogel may be about 5 to 200 μm, about 10 to 100 μm, or about 20 to 50 μm. Since the aerogel having the average particle size within the above range is included, thermal insulation may be improved, thereby delaying heat transfer between a plurality of battery cells.

[0061] The average particle size (D50) can be measured, for example, using a laser diffraction method or a scanning electron microscope (SEM), where the average particle size (D50) of the particles can be defined as the particle size at 50% in the particle size distribution (corresponding to the particle size that accumulates 50% of the volume in the particle size distribution).

[0062] The content of aerogel may be about 10 wt% to 90 wt%, about 30 wt% to 70 wt%, or about 40 wt% to 60 wt% based on the total amount of solids in the aerogel composition. When the aerogel composition including aerogel within the above range is used to manufacture a battery insulating sheet, the thermal insulation of the battery insulating sheet can be improved.

[0063] In example embodiments, the binder may include an aqueous polymer binder. For example, the aqueous polymer binder may be or include at least one of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

[0064] The water-based polymer may be or include, for example, but is not limited to, at least one of polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinyl pyrrolidone.

[0065] The anionic water-soluble polymer may include a polymer having at least one functional group of carboxylic acid, sulfonic acid, sulfate, phosphate, and salts thereof. For example, the anionic water-soluble polymer may be or include a polymer having a carboxylic acid group, and may include, but is not limited to, polymaleic acid as an example.

[0066] The cationic water-soluble polymer may include a polymer having at least one functional group of amine, ammonium, phosphonium, sulfonium and salts thereof. For example, the cationic water-soluble polymer may be a polymer having an amine group, and may be, but is not limited to, at least one of polyvinylamine and polyamine as an example.

[0067] The water-dispersible polymer may be, but is not limited to, at least one of a water-dispersible polyurethane and a water-dispersible polyester.

[0068] The binder may include at least one of a water-based polymer and a water-dispersible polymer. For example, the binder may include a water-based polymer having adhesive properties and dispersibility and a water-dispersible polymer having fire resistance. As an example, the binder may include polyvinyl alcohol and water-dispersible polyurethane.

[0069] The weight ratio of the water-based polymer to the water-dispersible polymer may be about 1:1 to 1:5, about 1:1 to 1:4, or about 1:2 to 1:3. When the weight ratio of the water-based polymer to the water-dispersible polymer is within the above range, in addition to improving the thermal insulation, dust formation, and compressibility of the battery insulating sheet, the fire resistance and mechanical properties of the battery insulating sheet may be further improved.

[0070] The binder may be present in an amount of about 0.5 wt% to 20 wt%, about 2 wt% to 15 wt%, or about 8 wt% to 15 wt%, based on the total amount of solids in the aerogel composition. When the aerogel composition including the binder within the above range is used to manufacture a battery insulating sheet, the dusting property of the battery insulating sheet can be improved.

[0071] In example embodiments, the dispersant may be at least one of a surfactant and a phosphate salt. For example, the dispersant may include, but is not limited to, at least one of a nonionic surfactant, an anionic surfactant, an amphoteric surfactant, a natural surfactant (such as lecithin), and a phosphate ester.

[0072] Further including a dispersant can further improve the dispersibility of the aerogel in the aerogel composition, thereby substantially uniformly dispersing the fibrous support and the aerogel.

[0073] The content of the dispersant may be in the range of about 0.1 wt% to 6 wt%, about 0.1 wt% to 5 wt%, or about 0.1 wt% to 3 wt%, based on the total amount of solids in the aerogel composition. When the dispersant is included in any of the above ranges, the aerogel composition can be manufactured at low cost and used to manufacture a battery insulation sheet having desired, advantageous or improved thermal insulation, fire resistance, mechanical properties, and dust formation.

[0074] In example embodiments, the binder and the dispersant may be included in a weight ratio of about 1:0.001 to 1:0.67, about 1:0.001 to 1:0.5, or about 1:0.001 to 1:0.3. Mixing the binder and the dispersant in a weight ratio within any of the above ranges may allow the aerogel to be more uniformly dispersed in the aerogel layer.

[0075] In example embodiments, the reinforcing material may be included at about 25 wt % to 60 wt %, the aerogel may be included at about 30 wt % to 70 wt %, and the binder may be included at about 2 wt % to 15 wt % based on the total amount of solids in the aerogel composition.

[0076] As an example, based on the total amount of solids in the aerogel composition, the included reinforcing material may account for about 30 wt% to 50 wt%, the included aerogel may account for about 40 wt% to 60 wt%, and the included binder may account for 8 wt% to 15 wt%. When the aerogel composition is formed within any of the above ranges, desired, advantageous or improved thermal insulation and fire resistance can be achieved while improving mechanical properties, and the bonding between the reinforcing material and the aerogel can be improved, thereby reducing or preventing dust generation.

[0077] In example embodiments, based on the total amount of solids in the aerogel composition, the reinforcing material may be included at about 25 wt % to 60 wt %, the aerogel may be included at about 30 wt % to 70 wt %, the binder may be included at about 2 wt % to 15 wt %, and the dispersant may be included at about 0.1 wt % to 5 wt %.

[0078] As an example, based on the total amount of solids in the aerogel composition, the included reinforcing material may account for about 30 wt% to 50 wt%, the included aerogel may account for about 40 wt% to 60 wt%, the included binder may account for about 5 wt% to 10 wt%, and the included dispersant may account for about 0.1 wt% to 3 wt%. When the aerogel composition is formed within any of the above ranges, the dispersibility of the aerogel can be improved, so that the desired, favorable or improved thermal insulation and fire resistance can be achieved while improving the mechanical properties, and the bonding between the reinforcing material and the aerogel can be improved, thereby reducing or preventing dust generation.

[0079] In example embodiments, the solvent may be at least one of a polar solvent and a non-polar solvent.

[0080] The polar solvent may be water, an alcohol solvent or a combination thereof.

[0081] The water may include, for example, purified water, deionized water, or a combination thereof.

[0082] The alcohol solvent may be, but is not limited to, at least one of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol and glycerol.

[0083] The non-polar solvent may include a hydrocarbon solvent. For example, the hydrocarbon solvent may be at least one of hexane, pentane, heptane, toluene and benzene, and may be, but is not limited to, an alkane solvent (such as hexane) or a mixture including an alkane solvent.

[0084] 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, water may not mix well with the hydrophobic aerogel. In an example embodiment, the aerogel can be uniformly dispersed by controlling the design of the mixing operation, the mixing conditions, the addition of a binder and a dispersant, and the amount of the binder and the dispersant. This uniform dispersion of the aerogel in the aerogel composition can form a battery insulation sheet with desired, favorable or improved thermal insulation, fire resistance, mechanical properties and dust formation with a small thickness without using a large amount of a binder.

[0085] The solvent may be included such that the weight ratio of the solvent to the total amount of solids in the aerogel composition is about 1:1 to 1:90. For example, the weight ratio of the solvent to the total amount of solids in the aerogel composition may be about 1:50 to 1:70, about 1:20 to 1:30, or about 1:2 to 1:10. By controlling the weight ratio of the solvent to the total amount of solids in the aerogel composition within the above range, the viscosity may be controlled to coat the aerogel composition.

[0086] In example embodiments, the aerogel composition may further include a silane compound. The silane compound may be or include, for example, at least one of 3-(methacryloyloxy)propyltrimethoxysilane, methyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octadecyltrimethoxysilane, ethyltriethoxysilane, and 3-glycidyloxypropyltrimethoxysilane. Further including a silane compound may further improve dispersibility.

[0087] In example embodiments, additives may be further included, such as, for example, wetting agents, emulsifiers, extenders, viscosity regulators, pH regulators, stabilizers, antioxidants, acid or base capture agents, metal deactivators, defoamers, antistatic agents, thickeners, adhesion promoters, coupling agents, flame retardants, impact modifiers, pigments, dyes, colorants, or deodorants.

[0088] A method of manufacturing an aerogel composition according to an example embodiment may include: mixing a solvent with a functional material including a binder, a dispersant, or a combination thereof to manufacture a solvent mixture; mixing the solvent mixture with an aerogel to manufacture an aerogel mixture; and mixing the aerogel mixture with a reinforcing material to manufacture the aerogel composition, wherein the reinforcing material may include a first fiber support and a second fiber support, and the first fiber support and the second fiber support may have different compositions.

[0089] In mixing the solvent with the functional material to produce the solvent mixture, the solvent may be mixed with the binder or may be mixed with the binder and the dispersant. The detailed description of the solvent, the binder, and the dispersant may be similar or the same as the above description.

[0090] In mixing the solvent mixture with the aerogel to produce the aerogel mixture, the aerogel may be added in a powder form, and the detailed description of the aerogel may be similar or the same as the above description.

[0091] In mixing the aerogel mixture with the reinforcing material to manufacture the aerogel composition, the detailed descriptions of the first fiber support, the second fiber support, and the reinforcing material may be similar or identical to the above descriptions.

[0092] In each of mixing the solvent with a functional material including a binder, a dispersant or a combination thereof 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, a mixer may be used for mixing. For example, the mixer may include, but is not limited to, a planetary mixer and a Thinky mixer. TM mixer.

[0093] As an example, a planetary mixer can be used to mix the solvent mixture with the aerogel. Using a planetary mixer to mix the solvent mixture with the aerogel can result in the aerogel being substantially uniformly dispersed in the solvent.

[0094] A planetary mixer may be a device that can be used to mix or stir different substances in order to produce a homogenous mixture. A planetary mixer may include blades that are capable of planetary motion.

[0095] In example embodiments, the planetary mixer may include at least one of one or more planetary blades and one or more high speed dispersing blades. As an example, the planetary mixer may include at least one planetary blade and at least one high speed dispersing blade.

[0096] Each or at least one of the planetary blades and the high-speed dispersion blades can be rotated substantially continuously about its axis. The rotation speed can be expressed in revolutions per minute (rpm).

[0097] In an example 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. Low speed and high speed refer to the relative rotation speed between the first blade and the second blade. As an example, the first blade may be an open blade and the second blade may be a Despa TM blade.

[0098] The rotation speed of the first blade may be, for example, about 10 rpm to 100 rpm, about 10 rpm to 60 rpm, or about 30 rpm to 70 rpm. The rotation speed of the second blade may be, for example, about 100 rpm to 2000 rpm, about 100 rpm to 1000 rpm, about 300 rpm to 1700 rpm, or about 500 rpm to 1700 rpm.

[0099] When the functional material is added to the solvent and mixed with the solvent, the rotation speed of the first blade of the mixer may be in the range of about 10 rpm to 60 rpm, about 20 rpm to 50 rpm, or about 30 rpm to 40 rpm, and the rotation speed of the second blade may be about 300 rpm to 1700 rpm, about 600 rpm to 1000 rpm, or about 700 rpm to 800 rpm. As described above, when the solvent and the functional material are mixed with each other, a solvent mixture in which a binder, a dispersant, or a combination thereof is substantially uniformly dispersed may be produced to facilitate mixing of aerogels in subsequent operations.

[0100] When the solvent mixture and the aerogel are mixed with each other, the rotation speed of the first blade of the mixer may be about 30 rpm to 70 rpm, about 40 rpm to 70 rpm, or about 60 rpm to 70 rpm, and the rotation speed of the second blade may be about 500 rpm to 1700 rpm, about 600 rpm to 1600 rpm, or about 800 rpm to 1500 rpm. When the aerogel is added to the solvent mixture and mixed with the solvent mixture as described above, the aerogel can be hindered or prevented from aggregating together to induce uniform dispersion.

[0101] When the aerogel mixture and the reinforcement material are mixed with each other, the rotation speed of the first blade of the mixer may be about 10rpm to 60rpm, about 20rpm to 50rpm, or about 30rpm to 40rpm, and the rotation speed of the second blade may be about 300rpm to 1700rpm, about 400rpm to 1500rpm, or about 800rpm to 1200rpm. Mixing the aerogel mixture with the reinforcement material as described above can remove air bubbles in the aerogel composition, control viscosity, and facilitate the dispersion of the reinforcement material in the uniformly dispersed aerogel, so that the aerogel surrounds the reinforcement material in the aerogel composition. A binder may be present between the aerogel and the reinforcement material to improve the bonding between the aerogel and the reinforcement material.

[0102] A battery insulation sheet according to example embodiments may include: a first substrate; a second substrate; and an aerogel layer formed between the first substrate and the second substrate, wherein the aerogel layer may be formed using the aerogel composition according to the above example embodiments.

[0103] Figure 1 is a schematic diagram illustrating a structure of a battery insulation sheet according to an example embodiment.

[0104] refer to Figure 1 In example embodiments, the battery insulating 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 fiber support 121 is shown as a thick line and the second fiber support 122 is shown as a thin line. Components other than the first fiber support 121 and the second fiber support 122 are not shown in order to show the dispersion of the first fiber support 121 and the second fiber support 122 in detail, and this should not be interpreted as the aerogel layer 120 not including components other than the first fiber support 121 and the second fiber support 122. In the aerogel layer 120, each of the first fiber support 121 and the second fiber support 122 may be vertically oriented and horizontally oriented. In Figure 1 In the embodiment, the first substrate 110 and the second substrate 130 may be made of or include the same material or different materials.

[0105] Since the aerogel layer 120 including the aerogel composition according to the example embodiment is formed between the first substrate 110 and the second substrate 130, the thermal insulation, fire resistance, and mechanical properties of the battery insulating sheet 100 can be improved, and when the battery insulating sheet 100 is manufactured or installed in a battery, the aerogel can be hindered or prevented from falling off and generating dust.

[0106] Figure 2 is a schematic diagram illustrating a battery insulation sheet according to an example embodiment formed between a plurality of battery cells.

[0107] refer to Figure 2 The battery insulating sheet 100 according to the example embodiment may be formed between a plurality of battery cells 200 included in a battery module. The upper and lower surfaces of the battery insulating sheet 100, namely, Figure 1 The first substrate 110 and the second substrate 130 of the battery insulating sheet 100 illustrated in the figure may be respectively disposed to face the battery cells 200 adjacent thereto. When the battery insulating sheet 100 according to the example embodiment is formed between a plurality of battery cells 200, a battery module capable of pre-blocking or blocking a flame in one battery cell may be provided, thereby reducing or substantially inhibiting the spread of flame to other battery cells with a higher level of safety, thereby reducing or substantially inhibiting the spread of flame in the battery module including the battery insulating sheet.

[0108] In the battery insulating sheet, the detailed description of the aerogel composition constituting the aerogel layer may be similar or identical to the above description.

[0109] Return to reference Figure 1 As each of the first substrate 110 and the second substrate 130, various substrates such as, but not limited to, resin, metal, inorganic materials other than metal, or mixtures thereof may be used. The form of the substrate may be, but not limited to, a film, a membrane, a sheet, etc.

[0110] The resin may be or include, for example, at least one of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0111] The metal may be or include, for example, at least one of copper, nickel, cobalt, iron, chromium, vanadium, palladium, ruthenium, rhodium, molybdenum, tungsten, iridium, silver, gold, and platinum. When a substrate made of any of the above metals or a substrate including any of the above metals is used, the substrate may be subjected to an anticorrosion treatment or an insulation treatment as required.

[0112] The inorganic material other than the metal may be or include at least one of calcium carbonate (CaCO 3 ), talc, and mica.

[0113] As an example, each or at least one of the first substrate 110 and the second substrate 130 may include an inorganic material other than a metal, and as a specific example, each or at least one of the first substrate 110 and the second substrate 130 may include mica. In this case, thermal insulation, durability, etc. of the battery insulating sheet may be improved.

[0114] refer to Figure 1 and Figure 2 In example embodiments, each or at least one of the first fiber support 121 and the second fiber support 122 in the aerogel layer may have a vertical orientation, a horizontal orientation, or a combination thereof. As an example, each of the first fiber support 121 and the second fiber support 122 in the aerogel layer 120 may have a substantially consistent vertical orientation and a substantially consistent horizontal orientation. In this case, the compressibility of the aerogel layer 120 may be further improved to absorb pressure applied from one battery cell 200 to a battery cell 200 adjacent thereto during degradation and expansion of the battery cell 200, thereby improving the safety of the battery.

[0115] In example embodiments, the aerogel layer 120 may be formed to have a single layer structure or a multi-layer structure. When the aerogel layer 120 is formed to have a multi-layer structure, the aerogel layer may be formed to have about 2 to 10 layers, about 2 to 7 layers, or about 2 to 5 layers.

[0116] The method of manufacturing a battery insulation sheet according to example embodiments may include applying the aerogel composition according to example embodiments to a first substrate 110 and laminating a second substrate 130 on the applied aerogel composition to form a laminate.

[0117] In the method of manufacturing a battery insulating sheet, detailed descriptions of the substrate and the aerogel composition may be similar or identical to the above descriptions.

[0118] Applying the aerogel composition to the first substrate 110 and laminating the second substrate 130 on the applied aerogel composition may be performed using a general method.

[0119] Applying the aerogel composition to the first substrate 110 may be performed once or repeatedly performed two or more times.

[0120] In example embodiments, the method may further include pressing and drying the laminate after manufacturing the laminate.

[0121] Drying may be performed at a temperature of, for example, about 25° C. to 100° C., about 45° C. to 90° C., or about 60° C. to 85° C. When drying is performed under the above temperature conditions, a solid aerogel layer may be formed between the first substrate 110 and the second substrate 130 without a separate adhesive member or adhesive, while reducing or preventing detachment between the aerogel layer 120 and the first substrate 110 and detachment between the aerogel layer 120 and the second substrate 130, and the aerogel layer 120 may be formed into a shape in which aerogel is coated around a plurality of dispersed first fiber supports 121 and second fiber supports 122.

[0122] According to various examples, a battery insulating sheet may be manufactured without using a separate adhesive or forming an adhesive layer using a simple method of applying an aerogel composition according to an example embodiment to a first substrate 110, laminating a second substrate 130 on the aerogel composition to manufacture a laminate, and pressing and drying the laminate, thereby achieving desired, advantageous or improved thermal insulation, fire resistance, mechanical properties and dust formation even with a small thickness due to substantially uniform dispersion of the aerogel.

[0123] Hereinafter, examples will be described. However, the following examples are only intended to illustrate or describe the present disclosure and should not be construed as limiting the present disclosure. Contents not described herein can be fully inferred technically by those skilled in the art, so descriptions thereof will be omitted.

[0124] Manufacturing of battery insulation sheets

[0125] Example 1

[0126] 1. Manufacture of aerogel compositions

[0127] The solvent mixture was made by adding polyvinyl alcohol (Sigma Aldrich) as a binder to deionized water as a solvent and stirring at 30 rpm using an open blade and using Despa TM The blades were run at 700 rpm to mix the solvent mixture. 2 / g of aerogel was added to the solvent mixture and stirred at 70 rpm using an open blade and Despa TM The aerogel mixture was prepared by adding silica fiber (first fiber support) and glass wool (second fiber support) as reinforcing materials to the aerogel mixture in a weight ratio of 1:3 and stirring at 30 rpm with an open blade and using Despa TMThe blades were at 1200 rpm to mix the aerogel mixture. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0128] The solid content of the manufactured aerogel composition was found to be 50 wt% aerogel, 40 wt% reinforcement material and 10 wt% polyvinyl alcohol.

[0129] 2. Manufacturing of battery insulation sheets

[0130] The slurry of the aerogel composition was applied to a 0.1 mm thick mica sheet (Pamica TM , Muscovite TM ), another 0.1 mm thick mica sheet was laminated thereon in a sandwich manner, and a roll pressing method was used for coating. Subsequently, an aerogel layer was formed by drying at 60° C. for 24 hours to manufacture a battery insulating sheet. It was found that the total thickness of the manufactured battery insulating sheet was 1.38 mm.

[0131] Example 2

[0132] A battery insulating sheet was manufactured using substantially the same method as Example 1, except that the aerogel composition was manufactured by adding silica fiber and glass wool to an aerogel mixture at a weight ratio of 1:1 and mixing the aerogel mixture.

[0133] Example 3

[0134] A battery insulating sheet was manufactured using substantially the same method as Example 1, except that the aerogel composition was manufactured by adding silica fiber and glass wool to an aerogel mixture at a weight ratio of 3:1 and mixing the aerogel mixture.

[0135] Example 4

[0136] A battery insulating sheet was manufactured using substantially the same method as Example 1, except that the aerogel composition was manufactured by adding silica fiber and glass wool to an aerogel mixture at a weight ratio of 1:4 and mixing the aerogel mixture.

[0137] Example 5

[0138] A battery insulating sheet was manufactured using substantially the same method as Example 1, except that the aerogel composition was manufactured by adding silica fiber and glass wool to an aerogel mixture at a weight ratio of 4:1 and mixing the aerogel mixture.

[0139] Example 6

[0140] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that the aerogel composition was manufactured by adding ceramic wool instead of glass wool to the aerogel mixture and mixing the aerogel mixture.

[0141] Example 7

[0142] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that the aerogel composition was manufactured by adding glass fiber chopped strands instead of silica fibers to the aerogel mixture and mixing them.

[0143] Example 8

[0144] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that the aerogel composition was manufactured by adding glass fiber chopped strands instead of silica fiber and ceramic wool instead of glass wool to the aerogel mixture and mixing them.

[0145] Example 9

[0146] 1. Manufacture of aerogel compositions

[0147] The solvent mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich) as a binder and a surfactant (Triton-X100, Sigma Aldrich) as a dispersant to deionized water as a solvent and stirring at 30 rpm using an open blade and using Despa TM The blades were mixed at 700 rpm. 2 / g of aerogel was added to the solvent mixture and stirred at 70 rpm using an open blade and Despa TM The blade was mixed at 1500 rpm to produce an aerogel mixture. The aerogel composition was produced by adding silica fiber and glass wool as reinforcement materials to the aerogel mixture in a weight ratio of 1:3 and stirring at 30 rpm using an open blade and using Despa TM The blades were mixed at 1200 rpm. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0148] The solid content of the manufactured aerogel composition was found to be 50 wt% aerogel, 40 wt% reinforcing material, 9.9 wt% polyvinyl alcohol and 0.1 wt% dispersant.

[0149] 2. Manufacturing of battery insulation sheets

[0150] The slurry of the prepared aerogel composition was applied to a 0.1 mm thick mica sheet (PamicaTM , Muscovite TM ), another 0.1 mm thick mica sheet was laminated thereon in a sandwich manner, and a roll pressing method was used for coating. Subsequently, an aerogel layer was formed by drying at 60° C. for 24 hours to manufacture a battery insulating sheet. It was found that the total thickness of the manufactured battery insulating sheet was 1.38 mm.

[0151] Comparative Example 1

[0152] 1. Manufacture of aerogel compositions

[0153] The aerogel composition was prepared by mixing polyvinyl alcohol (Sigma Aldrich) as a binder and 2 Aerogel having a BET specific surface area of ​​1000 μg was added to deionized water as a solvent and mixed using a planetary mixer (DNTEK, PT-005).

[0154] The solid content of the produced aerogel composition was found to be 50 wt% aerogel and 50 wt% polyvinyl alcohol.

[0155] 2. Manufacturing of battery insulation sheets

[0156] The slurry of the prepared aerogel composition was applied to a 0.1 mm thick mica sheet (Pamica TM , Muscovite TM ), another 0.1 mm thick mica sheet was laminated thereon in a sandwich manner, and a roll pressing method was used for coating. Subsequently, an aerogel layer was formed by drying at 60° C. for 24 hours to manufacture a battery insulating sheet. It was found that the total thickness of the manufactured battery insulating sheet was 1.38 mm.

[0157] Comparative Example 2

[0158] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that only silica fiber was used as a reinforcing material.

[0159] Comparative Example 3

[0160] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that only glass wool was used as a reinforcing material.

[0161] Comparative Example 4

[0162] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that only glass fiber chopped strands were used as the reinforcing material.

[0163] Comparative Example 5

[0164] A battery insulating sheet was manufactured using substantially the same method as in Example 1, except that only glass mat was used as a reinforcing material.

[0165] Experimental example

[0166] Experimental Example 1: SEM Analysis

[0167] The cross section of the aerogel layer of each of the battery insulating sheets of Example 1, Example 4 and Example 7 and Comparative Example 1 was observed using a Hitachi S-4800 scanning electron microscope (SEM), and the results are shown in FIG. Figure 3 to Figure 6 middle. Figure 3 is a SEM image of the aerogel layer of the battery insulation sheet according to Example 1, Figure 4 is a SEM image of the aerogel layer of the battery insulation sheet according to Example 4, Figure 5 is a SEM image of the aerogel layer of the battery insulating sheet according to Example 7, and Figure 6 is a SEM image of the aerogel layer of the battery insulating sheet according to Comparative Example 1.

[0168] In Comparative Example 1, no reinforcing material exists, and as can be seen from Examples 1, 4, and 7 in which silica fibers, glass chopped strands, and glass wool are used in combination, the horizontal orientation and the vertical orientation of the reinforcing material are substantially consistent.

[0169] Experimental Example 2: Evaluation of compressibility

[0170] The compressibility of each of the battery insulating sheets manufactured in Examples 1 to 9 and Comparative Examples 1 to 5 was evaluated.

[0171] Using a universal testing machine (UTM), after adjusting the zero point, each battery insulating sheet was inserted between aluminum plates each having a thickness of 1 mm and compressed from 0 kN to 80 kN at a compression speed of 0.02 mm / sec to measure the change in thickness of the battery insulating sheet. In this way, a compression test was performed, and the ratio of the thickness at 40 kN to the thickness at 5 kN was expressed as a compression rate (i.e., compressibility). The results are shown in Table 1 below.

[0172] Experimental Example 3: Evaluation of Thermal Insulation

[0173] The thermal insulation of each of the battery insulating sheets manufactured in Examples 1 to 9 and Comparative Examples 1 to 5 was evaluated.

[0174] Each battery insulating sheet was placed between a pair of opposing 1 mm thick aluminum plates and placed on a hot press. The upper plate of the hot press was heated to 350°C, and the lower plate of the hot press was not heated and maintained at a starting temperature of 40°C. Subsequently, a pressure of 20 kN was applied to the lower plate of the hot press, and the temperature of the lower plate of the hot press was measured at 11 minutes. The results are shown in Table 1 below.

[0175] [Table 1]

[0176] Compression rate (%) Temperature of lower plate (℃) Example 1 58.8 73.4 Example 2 51.4 78.1 Example 3 46.2 82.4 Example 4 52.5 73.2 Example 5 45.5 85.9 Example 6 53.7 69.4 Example 7 46.7 78.1 Example 8 43.4 71.2 Example 9 59.2 73.6 Comparative Example 1 51.2 73.2 Comparative Example 2 43.2 86.1 Comparative Example 3 48.8 73.5 Comparative Example 4 43.8 78.8 Comparative Example 5 44.2 83.6

[0177] Referring to Table 1, it can be seen that the embodiments exhibit desirable, advantageous, or improved compressibility due to the improvement in porosity and orientation caused by including the first fibrous support and the second fibrous support in a certain ratio.

[0178] Referring to Examples 1 to 5, it is shown that the first fiber support (such as, for example Figure 1 The first fiber support 121 illustrated in FIG. 1 and the second fiber support (such as, for example, Figure 1 The results of evaluating the compressibility based on the content ratio of the first fiber support and the second fiber support (122) explained in , and it can be seen from Examples 1, 2 and 4 that better physical properties are achieved when the first fiber support and the second fiber support are included in a weight ratio of 1:1 to 1:4 (especially 1:3 to 1:4).

[0179] Referring to Example 1 and Examples 6 to 8, the results of evaluating the compressibility according to the combination of the first fiber support and the second fiber support are shown, and it can be seen from Examples 1 and 6 that when the first fiber support is silica fiber and the second fiber support is glass wool or ceramic wool, better compressibility is achieved.

[0180] As can be seen from Example 9, when the binder and the dispersant are mixed to produce the aerogel composition, the compressibility is further improved.

[0181] It can be seen from Comparative Example 1 that because no reinforcing material is included, the compressibility is relatively high, but the battery insulating sheet collapses structurally due to the lack of a fiber support therein, and it can be seen from Comparative Examples 2 to 5 that when a reinforcing material including a fiber support is used, the compressibility is lower than that in the embodiment.

[0182] Regarding thermal insulation, it can be seen from the examples that when different reinforcement materials are used, the difference in the temperature of the lower plate is not significant, which may mean that the combination of different reinforcement materials improves the compressibility as a mechanical property while not affecting thermal insulation.

[0183] It was found that when the content of the first fibrous support increases beyond a certain ratio, the content of the relatively long fibrous support increases, whereby the contact thermal conductivity between the internal fibrous supports increases, so that thermal insulation may be somewhat reduced.

[0184] However, it can be seen from Example 1 that, compared with Comparative Examples 2 to 5 in which a single fiber support was used, the thermal insulation was similar or better despite the use of different fiber supports.

[0185] As can be seen from Example 6 in which silica fiber was used as the first fibrous support to improve compressibility as a mechanical property and ceramic wool was used as the second fibrous support having good heat resistance, thermal insulation was significantly improved.

[0186] Therefore, it can be seen that when the first fibrous support and the second fibrous support are included in a weight ratio of 1:3 to 1:4 and when a fibrous support having good thermal insulation is mixed, desired, advantageous or improved physical properties are achieved.

[0187] As is apparent from the above description, a battery insulation sheet manufactured using an aerogel composition according to example embodiments may have desired, advantageous, or improved thermal insulation, fire resistance, and mechanical properties (such as durability and compressibility), may have a low manufacturing process cost, and may reduce or prevent generation of dust from the aerogel during the manufacturing process and in actual use.

[0188] Although example embodiments are described above, the present disclosure is not limited thereto, and it is considered that various modifications may be made within the scope of the claims, detailed description of example embodiments, and the accompanying drawings, and that these modifications also fall within the scope of the present disclosure.

Claims

1. An aerogel composition for a battery insulating sheet, the aerogel composition comprising: A reinforcing material comprising a first fiber support and a second fiber support; Aerogel; A functional material including at least one of a binder and a dispersant; as well as Solvents, The first fibrous support body and the second fibrous support body include components different from each other.

2. The aerogel composition according to claim 1, wherein At least one of the first fiber support and the second fiber support comprises at least one of glass, silica, rock, basalt, alumina, silicon carbide, boron, ceramic, and quartz, and At least one of the first fibrous support and the second fibrous support is in the form of at least one of fiber, powder, cotton, chopped strands, felt, and batting.

3. The aerogel composition according to claim 1, wherein The first fiber support comprises silica fibers or glass fiber chopped strands, and The second fiber support body includes glass wool, quartz wool or ceramic wool. 4 . The aerogel composition according to claim 1 , wherein the first fibrous support and the second fibrous support are included in a weight ratio within a range of 1:5 to 5:

1. 5 . The aerogel composition according to claim 1 , wherein at least one of the first fibrous support and the second fibrous support has an average length in the range of 50 μm to 20,000 μm and an average diameter in the range of 0.1 μm to 30 μm.

6. The aerogel composition according to claim 1, wherein the aerogel has a 2 / g~1,000m 2 / g in the range of BET specific surface area. 7 . The aerogel composition according to claim 1 , wherein the aerogel has an average particle size in the range of 5 μm to 200 μm.

8. The aerogel composition according to claim 1, wherein The binder comprises an aqueous polymer binder, and The aqueous polymer binder includes at least one of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

9. The aerogel composition according to claim 1, wherein the binder is included in an amount ranging from 0.5 wt% to 20 wt% based on the total amount of solids in the aerogel composition.

10. The aerogel composition of claim 1, wherein the dispersant comprises at least one of a surfactant and a phosphate-based salt.

11. The aerogel composition according to claim 1, wherein the dispersant is included in the range of 0.1 wt% to 6 wt% based on the total amount of solids in the aerogel composition. 12 . The aerogel composition according to claim 1 , wherein a weight ratio of the solvent to the total amount of solids in the aerogel composition is in the range of 1:1 to 1:

90.

13. The aerogel composition according to claim 1, wherein based on the total amount of solids in the aerogel composition, the reinforcing material is included in the range of 5wt% to 70wt%, the aerogel is included in the range of 10wt% to 90wt%, and the functional material is included in the range of 0.5wt% to 20wt%.

14. A method for producing an aerogel composition for a battery insulating sheet, the method comprising: mixing a solvent with a functional material including at least one of a binder and a dispersant to produce a solvent mixture; mixing the solvent mixture with an aerogel to produce an aerogel mixture; as well as The aerogel mixture is mixed with a reinforcing material to produce an aerogel composition, wherein The reinforcing material comprises a first fiber support and a second fiber support, and The first fibrous support body and the second fibrous support body include compositions different from each other.

15. A battery insulating sheet, comprising: a first substrate; a second substrate; as well as an aerogel layer between the first substrate and the second substrate, The aerogel layer comprises the aerogel composition according to any one of claims 1 to 13 or the aerogel composition manufactured by the method of claim 14. 16 . The battery insulation sheet according to claim 15 , wherein at least one of the first substrate and the second substrate includes at least one of a resin, a metal, and an inorganic material other than the metal. 17 . The battery insulation sheet of claim 15 , wherein at least one of the first fiber support and the second fiber support in the aerogel layer has at least one of a vertical orientation, a horizontal orientation, and a combination thereof.

18. A method for manufacturing a battery insulating sheet, the method comprising: applying the aerogel composition according to any one of claims 1 to 13 or the aerogel composition produced by the method of claim 14 to a first substrate; as well as A second substrate is laminated onto the applied aerogel composition to produce a laminate.

19. The method of claim 18, further comprising pressing and drying the laminate after manufacturing the laminate.

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