Thermal insulation sheet for rechargeable lithium battery and rechargeable lithium battery module including same

Abstract

The invention relates to a thermal insulation sheet for a rechargeable lithium battery and a rechargeable lithium battery module including the same. The thermal insulation sheet includes: a substrate sheet including a first substrate layer, an aerogel-containing layer, and a second substrate layer laminated in this order; and a coating surrounding the substrate sheet, and each of the first substrate layer and the second substrate layer includes one selected from the group consisting of: 70 grams per square meter (gsm) to 500 grams per square meter (gsm) of a glass fiber sheet; and a carbon fiber sheet of 50 gsm to 300 gsm, each of the first substrate layer and the second substrate layer has a thickness of 300 [mu] m to 5,000 [mu] m, the aerogel-containing layer has a thickness of 300 [mu] m to 5,000 [mu] m, and the aerogel is included in the aerogel-containing layer in an amount of 10 wt% to 90 wt%.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2024-0153536, filed on November 1, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] Embodiments of the present invention relate to a thermal insulation sheet for a rechargeable lithium battery and a rechargeable lithium battery module including the same. Background Technology

[0004] In recent years, with the rapid proliferation of battery-powered electronic devices (such as mobile phones, laptops, and electric vehicles), the demand for rechargeable batteries with high energy density and high capacity has increased rapidly. Correspondingly, research and development to improve the performance of rechargeable lithium batteries are actively underway.

[0005] A rechargeable lithium battery is a battery that includes a positive electrode and a negative electrode (the positive electrode and the negative electrode include active materials capable of inserting and deintercalating lithium ions) and an electrolyte, and generates electrical energy through oxidation and reduction reactions when lithium ions are inserted / deintercalated between the positive electrode and the negative electrode.

[0006] It may include multiple rechargeable lithium batteries to form a rechargeable lithium battery module.

[0007] In rechargeable lithium battery modules, it is desirable to block heat propagation and / or heat transfer between adjacent battery cells. Summary of the Invention

[0008] According to an embodiment of the present invention, a thermal insulation sheet for rechargeable lithium batteries is provided, which has excellent thermal insulation properties, flexibility, compressibility, dust resistance, heat resistance and durability.

[0009] According to another aspect of the embodiments of the present invention, a rechargeable lithium battery module including the above-described thermal insulation sheet for a rechargeable lithium battery is provided.

[0010] According to one or more embodiments, a thermal insulation sheet for a rechargeable lithium battery includes: a substrate sheet comprising a first substrate layer, an aerogel-containing layer, and a second substrate layer laminated sequentially; and a coating surrounding the substrate sheet, wherein each of the first and second substrate layers comprises a glass fiber sheet selected from the group consisting of: 70 g / m² to 500 g / m²; and 50 g / m² to 300 g / m² of carbon fiber sheet, and each of the first and second substrate layers has a thickness of 300 μm to 5,000 μm, the aerogel-containing layer has a thickness of 300 μm to 3,000 μm, and the aerogel is included in the aerogel-containing layer in an amount of 10% to 90% by weight.

[0011] According to one or more embodiments, a rechargeable lithium battery module includes: a plurality of battery cells arranged facing each other; and a thermal insulating sheet for the rechargeable lithium battery, arranged between adjacent battery cells among the plurality of battery cells.

[0012] Thermal insulation sheets for rechargeable lithium batteries according to one or more embodiments can provide excellent thermal insulation properties, thereby suppressing heat propagation and / or heat transfer within the rechargeable lithium battery module, thus improving the safety of the rechargeable lithium battery module.

[0013] Thermal insulation sheets for rechargeable lithium batteries according to one or more embodiments offer superior flexibility and compressibility, thereby improving the manufacturing and processability of thermal insulation sheets and rechargeable lithium battery modules.

[0014] Thermal insulation sheets for rechargeable lithium batteries according to one or more embodiments provide excellent dust protection, thereby improving the manufacturing and processability of thermal insulation sheets and rechargeable lithium battery modules.

[0015] Thermal insulation sheets for rechargeable lithium batteries according to one or more embodiments provide superior heat resistance and durability, thereby improving the lifespan of rechargeable lithium battery modules. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of a thermal insulation sheet for a rechargeable lithium battery according to an embodiment.

[0017] Figure 2 This is a perspective view of a rechargeable lithium battery module according to an embodiment.

[0018] Figure 3 for Figure 2 An exploded perspective view of a rechargeable lithium battery module.

[0019] Figure 4 A cross-sectional view of a battery cell according to an embodiment is shown for illustrative purposes.

[0020] Figure 5 A perspective view of a battery pack according to an embodiment is shown for illustrative purposes.

[0021] Figure 6 A perspective view of a battery pack according to an embodiment is shown for illustrative purposes.

[0022] Figure 7 The diagram illustrates a car body and car body components according to an embodiment.

[0023] Figure 8 The diagram illustrates a car body and car body components according to an embodiment. Detailed Implementation

[0024] In this document, some embodiments of the invention will be described in further detail. However, it should be understood that these embodiments are presented as examples and are not intended to limit the invention, which is defined by the scope of the claims.

[0025] Unless otherwise specifically stated in this specification, the term "on" another part (such as a layer, film, region, plate, etc.) includes not only the case where the part (such as a layer, film, region, plate, etc.) is "directly on" the other part (such as a layer, film, region, plate, etc.), but also the case where another part is inserted therebetween.

[0026] Unless otherwise specifically stated in this specification, the singular form may also include the plural form. Furthermore, unless otherwise specifically stated herein, the term "A or B" may mean "including A, including B, or including both A and B".

[0027] In this specification, the term "combination thereof" may refer to mixtures, laminates, composites, copolymers, alloys, blends, and reaction products of the components.

[0028] Thermal insulation sheet for rechargeable lithium batteries

[0029] A thermal insulation sheet for a rechargeable lithium battery according to an embodiment includes: a substrate sheet comprising a first substrate layer, an aerogel-containing layer, and a second substrate layer laminated sequentially; and a coating surrounding the substrate sheet, wherein each of the first and second substrate layers comprises one selected from the group consisting of: a glass fiber sheet of 70 g / m² to 500 g / m²; and a carbon fiber sheet of 50 g / m² to 300 g / m², each of the first and second substrate layers having a thickness of 300 μm to 5,000 μm, the aerogel-containing layer having a thickness of 300 μm to 5,000 μm, and the aerogel being included in the aerogel-containing layer in an amount of 10% to 90% by weight. In this embodiment, the thermal insulation sheet includes an aerogel-containing layer and a substrate layer (the first and second substrate layers), and the thermal insulation sheet provides excellent thermal insulation properties, dust resistance, heat resistance, and durability. Both the aerogel-containing layer and the substrate layer contribute to improving the thermal insulation properties, dust resistance, heat resistance, and durability of the thermal insulation sheet.

[0030] In this document, the thermal insulation sheet according to the embodiments will be described in further detail.

[0031] substrate

[0032] The substrate comprises a first substrate layer, an aerogel-containing layer, and a second substrate layer, which are laminated sequentially.

[0033] First substrate layer

[0034] In the thermal insulation sheet, a first substrate layer supports an aerogel layer and a second substrate layer.

[0035] In a thermally insulating sheet, the first substrate layer may include at least one layer, that is, one, two or more layers.

[0036] In an embodiment, the first substrate layer comprises one selected from the group consisting of: 70 gsm to 500 gsm (e.g., 70 gsm, 80 gsm, 90 gsm, 100 gsm, 110 gsm, 120 gsm, 130 gsm, 140 gsm, 150 gsm, 160 gsm, 170 gsm, 180 gsm, 190 gsm, 200 gsm, 210 gsm, 220 gsm, 230 gsm, 240 gsm, 250 gsm, 260 gsm, 270 gsm, 280 gsm, 290 gsm, 300 gsm, 310 gsm, 320 gsm, 330 gsm, 340 gsm, 350 gsm, 360 gsm, 370 gsm, 380 gsm, 3 ...00 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 g gsm, 390 gsm, 400 gsm, 410 gsm, 420 gsm, 430 gsm, 440 gsm, 450 gsm, 460 gsm, 470 gsm, 480 gsm, 490 gsm, 500 gsm, 80 gsm~200 gsm or 90 gsm~120gsm) fiberglass sheets; and 50gsm~300gsm (such as 50gsm, 60gsm, 70gsm, 80gsm, 90gsm, 100gsm, 110gsm, 120gsm, 130gsm, 140gsm, 150gsm, 160gsm, 170gsm, 180 gsm, 190 gsm, 200 gsm, 210 Carbon fiber sheets in gsm, 220 gsm, 230 gsm, 240 gsm, 250 gsm, 260 gsm, 270 gsm, 280 gsm, 290 gsm, 300 gsm, 50 gsm~200 gsm or 70 gsm~150 gsm.

[0037] Fiberglass sheets are generally supplied in the form of fiberglass fabric or felt and can be used to manufacture thermal insulation sheets by laminating fiberglass sheets onto a substrate. During the lamination process, the fiberglass is combined with resin to create a composite material with high strength and high heat resistance, and the laminate can be cured at high temperatures (curing process) to enhance strength and heat resistance.

[0038] Fiberglass sheets possess electrical insulation and thermal barrier properties, are simple to manufacture, and can be easily processed into various shapes. Furthermore, fiberglass sheets have uniform thickness and structure, strong chemical resistance, are flexible, and exhibit heat resistance and stability at high temperatures.

[0039] Fiberglass sheets may include at least one of, for example, E-glass, S-glass, C-glass, ECR-glass, AR-glass, and D-glass.

[0040] Carbon fiber sheets exhibit excellent thermal conductivity and possess heat resistance and high tensile strength at high temperatures, thus ensuring structural safety. Furthermore, carbon fiber sheets are highly chemically resistant, heat-resistant at high temperatures, and can be easily processed into various shapes.

[0041] In this embodiment, the carbon fiber sheet may include at least one of polyacrylonitrile carbon fiber, pitch carbon fiber, and rayon carbon fiber.

[0042] In embodiments, the first substrate layer may have a thickness of 300 μm~5,000 μm (eg, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1,000 μm, 1,100 μm, 1,200 μm, 1,300 μm, 1,400 μm, 1,500 μm, μm, 1,600 μm, 1,700 μm, 1,800 μm, 1,900 μm, 2,000 μm, 2,100 μm, 2,200 μm, 2,300 μm, 2,400 μm, 2,500 μm, 2,600 μm, 2,700 μm, 2,800 μm, 2,900 μm, 3,000 μm, 3,100 μm, 3,200 Thicknesses ranging from 3,300 μm, 3,400 μm, 3,500 μm, 3,600 μm, 3,700 μm, 3,800 μm, 3,900 μm, 4,000 μm, 4,100 μm, 4,200 μm, 4,300 μm, 4,400 μm, 4,500 μm, 4,600 μm, 4,700 μm, 4,800 μm, 4,900 μm, 5,000 μm, 500 μm to 4,000 μm, or 800 μm to 2,000 μm. Within these ranges, the first substrate layer can be used in a thermally insulating sheet.

[0043] Aerogel layer

[0044] The aerogel layer may be a separate layer independent of the first substrate layer. Here, the term "separate layer independent of the first substrate layer" means that the aerogel layer is not formed in the first substrate layer by impregnation or the like, but rather that the first substrate layer and the aerogel layer are formed as completely separate, discontinuous layers.

[0045] In a thermal insulation sheet, the aerogel layer may include at least one layer, that is, one, two or more layers.

[0046] The aerogel-containing layer includes a fiber carrier, aerogel, and binder.

[0047] Fiber carriers can be used to support aerogel layers and improve the compressibility of thermal insulation sheets.

[0048] The fiber carrier can be, for example, glass wool, wool felt or chopped strand mat.

[0049] The fibers constituting the fiber carrier may include at least one of natural fibers, glass fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers. For example, the compressibility of the fiber carrier can be further improved by using glass fibers.

[0050] Natural fibers may be fibers made from at least one of hemp, jute, flax, coconut fiber, ramie, and cellulose. Mineral fibers may be fibers made from at least one of basalt, wollastonite, alumina, silica, slag, and rock. Polymer fibers may be fibers made from at least one of nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamide-imide, polyester (such as polyethylene terephthalate or polybutylene terephthalate), and polyolefin (such as polyethylene or polypropylene).

[0051] In some embodiments, the fiber carrier may be glass wool, for example.

[0052] The fibers in the fiber carrier can have an aspect ratio of 1 or greater (e.g., 1 to 5,000). Within this range, an aerogel layer can be firmly formed, and the durability of the thermal insulation sheet can be improved. Here, the term "aspect ratio" refers to the ratio of the length of the fiber to the diameter of the fiber in the fiber carrier.

[0053] In this embodiment, the fibers in the fiber carrier may have a length of 50 μm to 1,000 μm (e.g., 70 μm to 800 μm or 100 μm to 600 μm). Within this range, an aerogel layer can be firmly formed, and the durability of the thermal insulation sheet can be improved.

[0054] In embodiments, the fibers in the fiber carrier may have a diameter of 0.1 μm to 20 μm (e.g., 0.1 μm to 15 μm, 0.1 μm to 5 μm, 1 μm to 15 μm, or 3 μm to 10 μm). Within these ranges, an aerogel layer can be firmly formed, and the durability of the thermal insulation sheet can be improved. Here, the term "diameter" refers to the diameter when the fiber has a circular cross-section, or, if the fiber cross-section is not circular, to the length of its major axis.

[0055] In this embodiment, the fiber carrier is included in the aerogel-containing layer in an amount of 5% to 70% by weight. Within this range, the durability of the thermal insulation sheet can be easily improved. For example, the fiber carrier can be included in amounts of 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 40 ... The following amounts are included in the aerogel layer: 42% by weight, 43% by weight, 44% by weight, 45% by weight, 46% by weight, 47% by weight, 48% by weight, 49% by weight, 50% by weight, 51% by weight, 52% by weight, 53% by weight, 54% by weight, 55% by weight, 56% by weight, 57% by weight, 58% by weight, 59% by weight, 60% by weight, 61% by weight, 62% by weight, 63% by weight, 64% by weight, 65% by weight, 66% by weight, 67% by weight, 68% by weight, 69% by weight, 70% by weight, 10% by weight to 60% by weight, 25% by weight to 60% by weight, or 25% by weight to 50% by weight. Within these ranges, the flexibility and durability of the thermal insulation sheet can be easily improved.

[0056] Aerogels can provide thermal insulation to aerogel-containing layers.

[0057] According to the implementation method, the aerogel can have a diameter of 500 m. 2 / g~1,000 m 2 Specific surface area per g. For example, the specific surface area can be 500 m². 2 / g~950 m 2 / g、550 m 2 / g~950 m 2 / g or 600 m 2 / g~900 m 2 / g. Within the above range, heat transfer and heat propagation between multiple battery cells can be easily prevented or substantially prevented. Here, the term "specific surface area" can refer to the specific surface area obtained by Brunol-Emmett-Taylor (BET) specific surface area analysis.

[0058] According to embodiments, the aerogel can have an average particle size of 5 μm to 200 μm. For example, the aerogel can have an average particle size of 10 μm to 100 μm or 20 μm to 50 μm. Within these ranges, heat transfer between multiple battery cells can be easily delayed by improving the thermal insulation properties of the thermal insulation sheet. Here, the term "average particle size" refers to the average particle size (D). 50 The average particle size (D) represents the diameter of particles that constitute 50% of the total volume in the particle size distribution. 50 The diameter of particles can be measured by methods known to those skilled in the art, and can be measured, for example, by a particle size analyzer, transmission electron microscopy, or using scanning electron microscopy. Alternatively, the diameter of particles can be measured using a measuring device employing dynamic light scattering, allowing for data analysis to count the number of particles in each particle size range, and from which the average particle size (D) can be calculated. 50 As another method, laser diffraction can be used to measure the average particle size (D). 50 If measured by laser diffraction, the particles to be measured can be dispersed in a dispersion medium and introduced into a commercially available laser diffraction particle size measurement device (e.g., Microtrac). TM The particle size distribution was measured using an ultrasonic wave at approximately 28 kHz and an output power of 60 W. The average particle size (D) was then calculated based on 50% by volume of the particle size distribution in the measuring device. 50 ).

[0059] When the cross-section of the material is circular, the term “average grain size” as used herein refers to the average circle diameter, and when the cross-section of the material is non-circular, the term “average grain size” refers to the average major axis length.

[0060] In this embodiment, the aerogel is included in the aerogel-containing layer in an amount of 10% to 90% by weight. Within this range, the thermal insulation properties of the thermal insulation sheet can be easily improved. For example, the aerogel can be in the following amounts: 10% by weight, 11% by weight, 12% by weight, 13% by weight, 14% by weight, 15% by weight, 16% by weight, 17% by weight, 18% by weight, 19% by weight, 20% by weight, 21% by weight, 22% by weight, 23% by weight, 24% by weight, 25% by weight, 26% by weight, 27% by weight, 28% by weight, 29% by weight, 30% by weight, 31% by weight, 32% by weight, 33% by weight, 34% by weight, 35% by weight, 36% by weight, 37% by weight, 38% by weight, 39% by weight, 40% by weight, 41% by weight, 42% by weight, 43% by weight, 44% by weight, 45% by weight, 46% by weight, 47% by weight, 48% by weight, 49% by weight, 50% by weight, 51% by weight, 52% by weight, 53% by weight. The following amounts are included in the aerogel layer: 54% by weight, 55% by weight, 56% by weight, 57% by weight, 58% by weight, 59% by weight, 60% by weight, 61% by weight, 62% by weight, 63% by weight, 64% by weight, 65% by weight, 66% by weight, 67% by weight, 68% by weight, 69% by weight, 70% by weight, 71% by weight, 72% by weight, 73% by weight, 74% by weight, 75% by weight, 76% by weight, 77% by weight, 78% by weight, 79% by weight, 80% by weight, 81% by weight, 82% by weight, 83% by weight, 84% by weight, 85% by weight, 86% by weight, 87% by weight, 88% by weight, 89% by weight, 90% by weight, 30% by weight to 70% by weight, 30% by weight to 65% by weight, or 45% by weight to 65% by weight. Within these ranges, the thermal insulation properties of the thermal insulation sheet can be improved.

[0061] Adhesives can improve the compressibility and dust resistance of thermal insulation sheets.

[0062] According to the embodiments, the binder may be an aqueous binder. Among the solvents described below, the aqueous binder has high solubility in water and can therefore be used to form an aerogel layer.

[0063] According to embodiments, the water-based binder may include at least one of cationic water-soluble polymers, anionic water-soluble polymers, and nonionic water-soluble polymers.

[0064] Cationic water-soluble polymers are polymers having functional groups such as amine, ammonium, phosphonium, sulfonium, or salts thereof. For example, a cationic water-soluble polymer may be a polymer having amine groups. For example, a cationic water-soluble polymer may include at least one of polyethyleneamine and polyamine.

[0065] Anionic water-soluble polymers are polymers having functional groups such as carboxylic acid groups, sulfonic acid groups, ester groups, phosphate ester groups, or salts thereof. For example, anionic water-soluble polymers can be polymers having carboxylic acid groups. For example, anionic water-soluble polymers can be polymaleic acid.

[0066] Nonionic water-soluble polymers may include at least one of polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, polyurethane, and polyester. Nonionic water-soluble polymers may be water-dispersible polymers or water-soluble polymers.

[0067] According to embodiments, the binder may comprise one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, and a mixture of one or more of polyurethane and polyester. In this case, dispersion properties can be readily provided by one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, and fire-resistant properties can be readily provided by one or more of polyurethane and polyester. For example, a mixture of polyvinyl alcohol and polyurethane may be used.

[0068] According to the embodiments, the weight ratio of one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone to one or more of polyurethane and polyester can be 1:1 to 1:5, for example, 1:1 to 1:4 or 1:2 to 1:3. Within the above range, the thermal insulation properties, dust resistance, fire resistance, and mechanical properties of the thermal insulation sheet can be improved.

[0069] In this embodiment, the adhesive is included in the aerogel layer in an amount of 0.5% to 20% by weight. Including the adhesive in an amount of 0.5% by weight or greater readily improves the dust resistance and durability of the thermal insulation sheet. Including the adhesive in an amount of 20% by weight or less readily improves the durability of the thermal insulation sheet. In this embodiment, for example, the adhesive may be included in the aerogel layer in amounts of 0.5% to 1% by weight, 2% to 15% by weight, or 5% to 10% by weight. Within these ranges, the dust resistance of the thermal insulation sheet can be readily improved.

[0070] According to the embodiment, the fiber carrier, aerogel, and binder can be included in the aerogel-containing layer in a total amount of 95% by weight or more (e.g., 95% to 100% by weight, 99% to 100% by weight, or 100% by weight). Within the above range, the effect of a thermal insulation sheet can be easily achieved.

[0071] The aerogel layer may further include at least one of a dispersant and a silane compound.

[0072] Dispersants can improve the dispersibility of aerogels in compositions containing aerogel layers, thereby enabling the preparation of aerogel layers in which the fiber carrier and aerogel are uniformly dispersed.

[0073] The dispersant may include at least one of a surfactant and a phosphate salt. The surfactant may include at least one of a nonionic surfactant, anionic surfactant, and amphoteric surfactant. The surfactant may include at least one of a natural surfactant (such as lecithin) and a non-natural surfactant (such as chemicals). The phosphate salt may be a phosphate-based salt.

[0074] The dispersant can be included in the aerogel-containing layer in an amount of 0.1% to 6% by weight. In embodiments, for example, the dispersant can be included in an amount of 0.1% to 5% by weight or 0.1% to 3% by weight. Within the above ranges, compositions for aerogel-containing layers can be prepared at low cost, and thermal insulation sheets with further improved thermal insulation properties, durability, and dust resistance can be provided.

[0075] According to the embodiments, the binder and dispersant may be included in a weight ratio of 1:0.001 to 1:0.7 (e.g., 1:0.001 to 1:0.67, 1:0.001 to 1:0.5, or 1:0.001 to 1:0.3). If the binder and dispersant are used together within the above ranges, they may be able to prepare an aerogel layer in which the aerogel is more uniformly dispersed.

[0076] Silane compounds can improve the dispersibility of aerogels in aerogel-containing layers.

[0077] According to embodiments, silane compounds may include at least one of alkyl-containing trialkoxysilanes (such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, octadecyltrimethoxysilane, etc.), epoxy-containing trialkoxysilanes (such as glycidyltrimethoxysilane, etc.), and unsaturated group-containing trialkoxysilanes (such as propyl 3-(trimethoxysilyl)methacrylate, etc.).

[0078] The aerogel layer may further include conventional additives known to those skilled in the art. Additives may include at least one of the following: wetting agents, emulsifiers, compatibilizers, viscosity modifiers, pH adjusters, stabilizers, antioxidants, acid or alkali scavengers, metal deactivators, defoamers, antistatic agents, tackifiers, adhesion improvers, binders, flame retardants, impact modifiers, pigments, dyes, colorants, and deodorizers.

[0079] According to embodiments, the airgel layer may have a thickness of 300 μm~5,000 μm (eg, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1,000 μm, 1,100 μm, 1,200 μm, 1,300 μm, 1,400 μm, 1,500 μm, μm, 1,600 μm, 1,700 μm, 1,800 μm, 1,900 μm, 2,000 μm, 2,100 μm, 2,200 μm, 2,300 μm, 2,400 μm, 2,500 μm, 2,600 μm, 2,700 μm, 2,800 μm, 2,900 μm, 3,000 μm, 3,100 Thicknesses ranging from 3,200 μm, 3,300 μm, 3,400 μm, 3,500 μm, 3,600 μm, 3,700 μm, 3,800 μm, 3,900 μm, 4,000 μm, 4,100 μm, 4,200 μm, 4,300 μm, 4,400 μm, 4,500 μm, 4,600 μm, 4,700 μm, 4,800 μm, 4,900 μm, 5,000 μm, 800 μm to 3,000 μm, or 1,500 μm to 2,200 μm are permissible. Within these ranges, aerogel-containing layers can be used in thermal insulation sheets.

[0080] An aerogel-containing layer can be formed using a composition for use with the aerogel-containing layer, the aerogel-containing layer comprising a fibrous carrier, an aerogel, and a binder. The composition for use with the aerogel-containing layer may further comprise at least one of a dispersant, a silane compound, and an additive.

[0081] In an embodiment, based on the solids content, the composition for the aerogel-containing layer may include 5% to 70% by weight (e.g., 10% to 60% by weight, 25% to 60% by weight, or 25% to 50% by weight) of a fiber carrier; 10% to 90% by weight (e.g., 30% to 70% by weight, 30% to 65% by weight, or 45% to 65% by weight) of aerogel; and 0.5% to 20% by weight (e.g., 2% to 15% by weight or 5% to 10% by weight) of an adhesive.

[0082] The method for preparing the aerogel layer will be described in further detail below.

[0083] Second substrate layer

[0084] In the thermal insulation sheet, the second substrate layer can support the first substrate layer and the aerogel-containing layer.

[0085] In the thermal insulation sheet, the second substrate layer may include at least one layer, that is, one, two or more layers.

[0086] The second substrate layer can be laminated onto the aerogel layer. The aerogel layer can be a separate layer independent of the second substrate layer. Here, the term "separate layer independent of the second substrate layer" means that the aerogel layer is not formed in the second substrate layer by impregnation or the like, but rather that the second substrate layer and the aerogel layer are formed as completely separate, discontinuous layers.

[0087] In an embodiment, the second substrate layer includes at least one selected from the group consisting of: 70 gsm to 500 gsm (e.g., 70 gsm, 80 gsm, 90 gsm, 100 gsm, 110 gsm, 120 gsm, 130 gsm, 140 gsm, 150 gsm, 160 gsm, 170 gsm, 180 gsm, 190 gsm, 200 gsm, 210 gsm, 220 gsm, 230 gsm, 240 gsm, 250 gsm, 260 gsm, 270 gsm, 280 gsm, 290 gsm, 300 gsm, 310 gsm, 320 gsm, 330 gsm, 340 gsm, 350 gsm, 360 gsm, 370 gsm, 380 gsm, 3 ...00 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 300 gsm, 30 gsm, 390 gsm, 400 gsm, 410 gsm, 420 gsm, 430 gsm, 440 gsm, 450 gsm, 460 gsm, 470 gsm, 480 gsm, 490 gsm, 500 gsm, 80 gsm~200 gsm or 90 gsm~120 gsm); and 50 gsm~300 gsm (such as 50 gsm, 60 gsm, 70 gsm, 80 gsm, 90 gsm, 100 gsm, 110 gsm, 120 gsm, 130 gsm, 140 gsm, 150 gsm, 160 gsm, 170 gsm, 180 gsm, 190gsm, 200gsm, 210 Carbon fiber sheets in gsm, 220 gsm, 230 gsm, 240 gsm, 250 gsm, 260 gsm, 270 gsm, 280 gsm, 290 gsm, 300 gsm, 50 gsm~200 gsm or 70 gsm~150 gsm.

[0088] Fiberglass sheets are generally supplied in the form of fiberglass fabric or felt and can be used to manufacture thermal insulation sheets by laminating fiberglass sheets onto a substrate layer. During the lamination process, the fiberglass is combined with resin to create a composite material with high strength and high heat resistance, and the laminate can be cured at high temperatures (curing process) to enhance strength and heat resistance. The resin can be derived from a binder containing an aerogel layer.

[0089] Fiberglass sheets possess electrical insulation and thermal barrier properties, are simple to manufacture, and can be easily processed into various shapes. Furthermore, fiberglass sheets have a uniform or substantially uniform thickness and structure, are highly chemically resistant, flexible, and exhibit heat resistance and stability at high temperatures.

[0090] Fiberglass sheets may include at least one of, for example, E-glass, S-glass, C-glass, ECR-glass, AR-glass, and D-glass.

[0091] Carbon fiber sheets exhibit excellent thermal conductivity and possess heat resistance and high tensile strength at high temperatures, thus ensuring structural safety. Furthermore, carbon fiber sheets are highly chemically resistant, heat-resistant at high temperatures, and can be easily processed into various shapes.

[0092] Carbon fiber sheets may include at least one of polyacrylonitrile carbon fibers, pitch-based carbon fibers, and rayon-based carbon fibers.

[0093] In embodiments, the second substrate layer may have a thickness of 300 μm to 5,000 μm (eg, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1,000 μm, 1,100 μm, 1,200 μm, 1,300 μm, 1,400 μm, 1,500 μm, μm, 1,600 μm, 1,700 μm, 1,800 μm, 1,900 μm, 2,000 μm, 2,100 μm, 2,200 μm, 2,300 μm, 2,400 μm, 2,500 μm, 2,600 μm, 2,700 μm, 2,800 μm, 2,900 μm, 3,000 μm, 3,100 μm, 3,200 Thicknesses ranging from 3,300 μm, 3,400 μm, 3,500 μm, 3,600 μm, 3,700 μm, 3,800 μm, 3,900 μm, 4,000 μm, 4,100 μm, 4,200 μm, 4,300 μm, 4,400 μm, 4,500 μm, 4,600 μm, 4,700 μm, 4,800 μm, 4,900 μm, 5,000 μm, 500 μm to 4,000 μm, or 800 μm to 2,000 μm. Within these ranges, the second substrate layer can be used in a thermally insulating sheet.

[0094] Inorganic layer

[0095] In one embodiment, an inorganic layer is formed on the entire surface of the substrate. The inorganic layer may be formed on the upper surface of the substrate, the lower surface opposite to the upper surface, and the side surface connecting the upper and lower surfaces.

[0096] According to the embodiments, the inorganic layer can be formed directly on the substrate. Here, the term "directly formed" means that no adhesive layer (e.g., pressure-sensitive adhesive layer) is formed between the substrate and the inorganic layer.

[0097] The inorganic layer includes inorganic materials, and the inorganic materials may include particles, provided that the particles have low thermal conductivity and can be stably fixed to each of the first substrate layer, the aerogel-containing layer, and the second substrate layer, without any limitation.

[0098] For example, inorganic materials can be metals, nonmetals, intermetallic compounds or alloys, nonmetallic intermetallic compounds or alloys, metal or nonmetal oxides, metal or nonmetal fluorides, metal or nonmetal nitrides, metal or nonmetal carbides, metal or nonmetal oxynitrides, metal or nonmetal borides, metal or nonmetal oxyborides, metal or nonmetal silicides, or mixtures thereof. In embodiments, the metal or nonmetal can be silicon (Si), aluminum (Al), selenium (Se), zinc (Zn), antimony (Sb), indium (In), germanium (Ge), tin (Sn), bismuth (Bi), transition metals, lanthanides, etc., but the present invention is not limited thereto. In embodiments, inorganic materials can be In₂O₃, silicon oxide (SiO₂), etc. x (e.g., SnO2), silicon nitrides (SiN) x ), silicon oxynitride (SiO) x N y ), aluminum oxide (Al) x O y ), ZnSe, ZnO, Sb2O3, etc.

[0099] In an embodiment, the inorganic material may include at least one of silicon oxide (e.g., silicon dioxide) and aluminum oxide (e.g., aluminum oxide).

[0100] In the implementation, the inorganic material may take the form of any one of the following: true sphere, amorphous, plate-like, cubic, etc.

[0101] In this embodiment, the inorganic material may have an average particle size of 0.005 μm to 10 μm (e.g., 0.01 μm to 1 μm). Within this range, an inorganic layer can be easily formed.

[0102] The inorganic layer may further include an adhesive to facilitate the coating of the inorganic material. The adhesive may include at least one of an aqueous adhesive and an organic adhesive, provided that the adhesive does not affect the aforementioned effects of the thermal insulation sheet.

[0103] In one embodiment, the adhesive may be at least one of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, and in another embodiment, the adhesive may be polyvinyl alcohol.

[0104] In an embodiment, the inorganic layer may comprise 70% to 99% by weight (e.g., 80% to 90% by weight) of inorganic material and 1% to 30% by weight (e.g., 10% to 20% by weight) of binder. Within these ranges, the aforementioned effects of the present invention can be readily achieved.

[0105] A coating, including an inorganic layer, surrounds a substrate and may include: a first coating formed on an upper and lower surface of the substrate; and a second coating formed on a side surface of the substrate. The first and second coatings may be the same or different inorganic layers. In embodiments, the first and second coatings may each have a thickness of 1 μm to 500 μm (e.g., 10 μm to 300 μm or 80 μm to 200 μm). Within these ranges, the coatings can be used in thermally insulating sheets and rechargeable lithium-ion battery modules.

[0106] Figure 1 This is a cross-sectional view of a thermal insulation sheet for a rechargeable lithium battery according to an embodiment.

[0107] refer to Figure 1 The thermal insulation sheet for a rechargeable lithium battery may include: a substrate 130A, including a first substrate layer 110A, a second substrate layer 110B facing the first substrate layer 110A, and an aerogel layer 120 laminated between the first substrate layer 110A and the second substrate layer 110B; a first coating 140 formed on the upper and lower surfaces of the substrate 130A; and a second coating 150 formed on the side surface of the substrate 130A.

[0108] This document describes a method for preparing a thermally insulating sheet according to an embodiment.

[0109] In an embodiment, the method for preparing a thermally insulating sheet may include: preparing a composition for an aerogel-containing layer comprising a fiber carrier, an aerogel, and a binder; coating a first substrate layer with the composition for an aerogel-containing layer, and further laminating a second substrate layer onto the composition for an aerogel-containing layer; drying the composition for an aerogel-containing layer coated on the first substrate layer to prepare a substrate sheet; and forming an inorganic layer on the entire surface of the substrate sheet.

[0110] Compositions for use with aerogel-containing layers include a fiber carrier, an aerogel, and a binder. The fiber carrier, aerogel, and binder may be the same as those described above.

[0111] The composition for use with an aerogel layer may further include at least one of the above-mentioned dispersants, silane compounds and additives.

[0112] Compositions used for aerogel-containing layers may further include a solvent.

[0113] The solvent may include at least one of polar solvents and nonpolar solvents.

[0114] Polar solvents may include water, alcohols, or combinations thereof. Water may include, for example, purified water, ultrapure water, or combinations thereof. Alcohols may include, for example, at least one of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol, and glycerol.

[0115] Nonpolar solvents may include hydrocarbon solvents. For example, hydrocarbon solvents may include at least one of aliphatic hydrocarbon solvents (e.g., alkane solvents such as hexane, pentane, heptane, etc.) and aromatic hydrocarbon solvents (such as toluene, benzene, etc.).

[0116] For example, solvents may include water. Using water as a solvent can effectively reduce raw material costs and post-processing costs.

[0117] In embodiments, the solvent may be included in a weight ratio of 1:1 to 1:90 relative to the total solids content of the composition for the aerogel layer. In embodiments, for example, the solvent to the total solids content of the composition for the aerogel layer may have a weight ratio of 1:50 to 1:70, 1:20 to 1:30, or 1:2 to 1:10. Within these ranges, the composition for the aerogel layer can be coated by controlling the viscosity of the composition for the aerogel layer.

[0118] Compositions for aerogel-containing layers can be prepared using solvents, fiber carriers, aerogels, and binders.

[0119] According to an embodiment, a composition for an aerogel-containing layer can be prepared by the following steps: mixing an adhesive into a solvent to prepare a first mixture (first step); mixing an aerogel into the first mixture to prepare a second mixture (second step); and mixing a fiber carrier into the second mixture to prepare a composition for an aerogel-containing layer (third step). In the step of preparing the first mixture, a dispersant, a silane compound, additives, etc., may be further mixed.

[0120] In each of the first, second, and third steps, a mixer can be used to mix the components. For example, a planetary mixer, a thinky mixer, or the like can be used as the mixer.

[0121] A planetary mixer may include at least one of one or more planetary blades and one or more high-speed dispersing blades. The planetary blades and the high-speed dispersing blades rotate continuously about their axes. Rotational speed may be expressed in revolutions per minute (rpm).

[0122] According to one embodiment, the planetary mixer may include a first blade and a second blade with different rotating shafts. For example, the first blade may be a low-speed blade, and the second blade may be a high-speed blade. Here, the terms "low-speed" and "high-speed" refer to relative rotational speeds. In one embodiment, the first blade may be an open blade, and the second blade may be a Despa blade. For example, the rotational speed of the first blade may be 10 rpm to 100 rpm or 10 rpm to 60 rpm. The rotational speed of the second blade may be 100 rpm to 2,000 rpm.

[0123] According to an embodiment, the second substrate layer may be further laminated onto the composition for the aerogel layer prior to drying.

[0124] An aerogel layer can be prepared by applying a composition for the aerogel layer and then drying the composition. In embodiments, drying can be performed at temperatures of 25°C to 100°C, 45°C to 90°C, or 60°C to 85°C. Within these ranges, an aerogel layer with excellent mechanical strength can be formed without separate adhesives or bonding components, while preventing or substantially preventing peeling between the first substrate layer and the aerogel layer, as well as peeling between the aerogel layer and the second substrate layer.

[0125] In one embodiment, an inorganic layer can be prepared by applying a slurry containing inorganic materials to the entire surface of a substrate and drying the slurry, such as by coating or spraying.

[0126] In an embodiment, the slurry containing inorganic materials may further include at least one of an aqueous binder and an organic binder to ensure uniform or substantially uniform formation of the inorganic layer.

[0127] In this embodiment, drying can be performed at temperatures of 25°C to 100°C, 45°C to 90°C, or 60°C to 85°C. Within these ranges, an aerogel layer with excellent mechanical strength can be formed without separate adhesives or bonding components, while preventing or substantially preventing peeling between the substrate and the inorganic layer.

[0128] Rechargeable lithium battery module

[0129] According to an embodiment, a rechargeable lithium battery module includes: a plurality of battery cells arranged facing each other; and a thermal insulating sheet for the rechargeable lithium battery disposed between adjacent battery cells among the plurality of battery cells.

[0130] Figure 2 and Figure 3 These are perspective views and exploded perspective views of a rechargeable lithium battery module according to an embodiment.

[0131] refer to Figure 2 and Figure 3 A rechargeable lithium battery module may include: a plurality of battery cells 100 arranged facing each other; and a thermal insulation sheet 200 for the rechargeable lithium battery disposed between the plurality of battery cells 100.

[0132] The thermal insulation sheet 200 for rechargeable lithium batteries is plate-shaped, wherein a first side of the thermal insulation sheet 200 can contact one side of a battery cell 100, and a second side opposite to the first side can contact one side of another battery cell 100.

[0133] The battery cell 100 may include: a housing 50 configured to house an electrode assembly including a positive electrode and a negative electrode; a cover plate 60 coupled to the housing 50 to seal the housing 50; and a positive electrode terminal 12 and a negative electrode terminal 22 electrically connected to the positive electrode and the negative electrode of the electrode assembly, respectively, and protruding outward from the cover plate 60.

[0134] The positive electrode may include a positive electrode current collector and a positive electrode active material layer formed on the positive electrode current collector. The positive electrode active material layer includes a positive electrode active material and may further include a binder and / or a conductive material. In an embodiment, based on 100% by weight of the positive electrode active material layer, the content of the positive electrode active material may be 90% to 99% by weight, and based on 100% by weight of the positive electrode active material layer, the content of the binder and the conductive material may each be 0.5% to 5% by weight.

[0135] In some embodiments, the positive electrode current collector may be made of Al foil, but the present invention is not limited thereto.

[0136] As the positive electrode active material, compounds capable of reversibly inserting and deintercalating lithium (lithiation intercalation compounds) can be used. In embodiments, a composite oxide of at least one lithium with a metal selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0137] The composite oxide may be a lithium transition metal composite oxide, and examples include lithium nickel oxides, lithium cobalt oxides, lithium manganese oxides, lithium iron phosphate compounds, cobalt-free nickel manganese oxides, or combinations thereof.

[0138] As an example, a compound represented by any of the following chemical formulas can be used: Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b- c Mn b Xc O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3 (0≤f≤2); Li a FePO4 (0.90≤a≤1.8).

[0139] In the above chemical formula, A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, or a combination thereof; D is O, F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L 1 It is Mn, Al, or a combination thereof.

[0140] The negative electrode includes a negative electrode current collector and a negative electrode active material layer disposed on the negative electrode current collector. The negative electrode active material layer includes a negative electrode active material and may further include a binder and / or a conductive material. In an embodiment, for example, based on 100% by weight of the negative electrode active material layer, the negative electrode active material layer may include 90% to 99.5% by weight of the negative electrode active material, 0.5% to 5% by weight of the binder, and 0% to 5% by weight of the conductive material.

[0141] The negative electrode active material includes a material capable of reversibly inserting / extracting lithium ions, lithium metal, an alloy of lithium and a metal, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0142] The material capable of reversibly inserting / extracting lithium ions may include a carbon-based negative electrode active material, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon include graphite, such as natural graphite or artificial graphite; and examples of amorphous carbon include soft carbon or hard carbon, mesophase pitch carbide, calcined coke, etc.

[0143] As the material capable of doping and dedoping lithium, a Si-based negative electrode active material or a Sn-based negative electrode active material may be used. The Si-based negative electrode active material may be silicon, a silicon-carbon composite, SiO x (0 < x ≤ 2), a Si-Q alloy, or a combination thereof.

[0144] The silicon-carbon composite may be a composite of silicon and amorphous carbon. According to an embodiment, the silicon-carbon composite may be in the form of silicon particles coated with amorphous carbon on the surface.

[0145] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core containing crystalline carbon and silicon particles, and an amorphous carbon coating provided on the surface of the core.

[0146] A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof may be used as the binder. If an aqueous binder is used as the binder in the negative electrode active material layer, the aqueous binder may further include a cellulose-based compound capable of imparting viscosity.

[0147] In an embodiment, a current collector selected from any one of copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive metal, and a combination thereof may be used as the negative electrode current collector.

[0148] The electrolyte for a rechargeable lithium battery may include a non-aqueous organic solvent and a lithium salt.

[0149] The non-aqueous organic solvent serves as a medium through which ions participating in the electrochemical reaction of the battery can move. The non-aqueous organic solvent may include a carbonate solvent, an ester solvent, an ether solvent, a ketone solvent, an alcohol solvent, an aprotic solvent, or a combination thereof, which may be used alone or in a combination of two or more of them.

[0150] In an embodiment, if a carbonate solvent is used, a cyclic carbonate and a chain carbonate may be used in combination.

[0151] Depending on the type of rechargeable lithium battery, a separator may be present between the positive electrode and the negative electrode. As such a separator, a polyethylene separator, a polypropylene separator, a polyvinylidene fluoride separator, or a multilayer film of two or more layers thereof may be used.

[0152] The diaphragm may include a porous substrate and a coating comprising an organic material, an inorganic material, or a combination thereof disposed on one or both (or opposite) surfaces of the porous substrate.

[0153] In embodiments, the organic material may include polyvinylidene fluoride polymers or (meth)acrylic acid polymers. The inorganic material may include inorganic particles selected from Al₂O₃, SiO₂, TiO₂, SnO₂, CeO₂, MgO, NiO, CaO, GaO, ZnO, ZrO₂, Y₂O₃, SrTiO₃, BaTiO₃, Mg(OH)₂, boehmite, and combinations thereof, but the invention is not limited thereto. The organic and inorganic materials may exist as a mixture in a coating, or may be present in a laminated form in which a coating comprising organic materials and a coating comprising inorganic materials are laminated together.

[0154] Figure 4 A cross-sectional view of a battery cell 100 according to an embodiment is shown for illustrative purposes.

[0155] refer to Figure 4 The battery cell 100 may include: an electrode assembly 40 having a positive electrode 10, a negative electrode 20, and a separator 30 inserted between the positive electrode 10 and the negative electrode 20; a housing 50 configured to house the electrode assembly 40; a positive electrode lead connector 11 connected to the positive electrode 10; a positive electrode terminal 12 connected to the positive electrode lead connector 11; a negative electrode lead connector 21 connected to the negative electrode 20; and a negative electrode terminal 22 connected to the negative electrode lead connector 21.

[0156] Rechargeable lithium battery modules according to one or more embodiments can be applied to automobiles, mobile phones and / or various types of electronic devices, but the invention is not limited thereto.

[0157] The rechargeable lithium battery module according to the above embodiments can be used to manufacture battery packs.

[0158] Figure 5 A perspective view of a battery pack according to an embodiment is shown for illustrative purposes.

[0159] Figure 6 A perspective view of a battery pack according to an embodiment is shown for illustrative purposes.

[0160] The battery pack 2000 according to an embodiment includes an assembly of individual batteries electrically connected to each other and a pack housing configured to house the batteries. For ease of illustration in the drawings, components for electrical connections between the batteries, such as busbars, cooling units, and external terminals, are not shown.

[0161] Battery pack 2000 may include multiple battery modules 1000 (e.g., regarding...) Figure 2 and Figure 3 The battery module described herein and a housing 2100 configured to house the battery module 1000. In an embodiment, for example, the housing 2100 may include a first housing 2101 and a second housing 2102 connected in a direction facing each other, wherein a plurality of battery modules 1000 are inserted therebetween. The plurality of battery modules 1000 may be electrically connected to each other using a busbar 2200, and the plurality of battery modules 1000 may be electrically connected to each other in series / parallel or a combination of series and parallel to obtain a desired electrical output.

[0162] Can Figure 5 and Figure 6 The battery pack 2000 described in the embodiment is installed in a vehicle (e.g.) Figure 7 and Figure 8 The vehicle shown is 3000. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle may include a four-wheeled vehicle or a two-wheeled vehicle.

[0163] Figure 7 The diagram illustrates a car body and car body components according to an embodiment.

[0164] Figure 8 The diagram illustrates a car body and car body components according to an embodiment.

[0165] like Figure 7 and Figure 8 As shown, the vehicle 3000 according to an embodiment includes a battery module 1000 and / or a battery pack 2000 including the battery module 1000 according to an embodiment of the present invention. The vehicle 3000 operates by receiving power from the battery module 1000 and / or the battery pack 2000 including the battery module 1000 according to an embodiment of the present invention.

[0166] In this document, embodiments and comparative examples of the present invention will be described. However, it should be understood that the following embodiments are provided merely as examples of the present invention and are not intended to limit the invention.

[0167] Example 1

[0168] Preparation of compositions containing aerogel layers

[0169] Polyvinyl alcohol (Sigma-Aldrich, PVA) as a binder was added to ultrapure water as a solvent, and the mixture was prepared by sequentially mixing with an open blade at 30 rpm and with a Despa blade at 700 rpm. An aerogel (with an 800 m...) was then... 2The first mixture was added with BET surface area ( / g), and the mixture was then mixed sequentially with open blades at 70 rpm and with Despa blades at 1,500 rpm to prepare the second mixture. Glass wool, acting as a fiber carrier, was added to the second mixture, and the mixture was then mixed sequentially with open blades at 30 rpm and with Despa blades at 1,200 rpm to prepare the composition for the aerogel layer. A planetary mixer (Dientech, PT-005) was used during mixing.

[0170] The prepared composition for the aerogel-containing layer is in the form of a slurry, and based on the solid content, the composition comprises 50% by weight of aerogel, 40% by weight of glass wool, and 10% by weight of polyvinyl alcohol.

[0171] Preparation of thermal insulation sheet

[0172] The first substrate layer comprises a glass fiber sheet (GSM: 100) with a thickness of 1 mm. A composition for the aerogel-containing layer is applied to the first substrate layer, and a second substrate layer comprising a glass fiber sheet (GSM: 100) with a thickness of 1 mm is laminated onto the composition for the aerogel-containing layer by a roll forming method. Subsequently, the resulting laminate is dried at 60°C for 24 hours to prepare a substrate sheet in which the glass fiber sheet, the aerogel-containing layer, and the glass fiber sheet are laminated in this order.

[0173] Polyvinyl alcohol (Sigma-Aldrich, PVA) as a binder was added to ultrapure water as a solvent, and then reacted with alumina (average particle size D). 50 A sol (500 nm) was mixed to prepare a composition for the first coating. Subsequently, the composition for the first coating was uniformly coated onto the upper and lower surfaces of a substrate using a rod coating method. The composition was then dried at 60°C for 24 hours to prepare a thermally insulating sheet in which a coating containing polyvinyl alcohol and alumina is formed on the upper and lower surfaces of the substrate. The composition for the first coating is in slurry form and, based on solids content, comprises 90 wt% alumina and 10 wt% polyvinyl alcohol.

[0174] Furthermore, polyvinyl alcohol (Sigma-Aldrich, PVA) as a binder was added to ultrapure water as a solvent, and mixed with silica (average particle size D). 50A sol-gel mixture (500 nm) was prepared to form a composition for a second coating, and the side surface of a substrate was dipped into the prepared composition for the second coating. Subsequently, the composition was dried at 60°C for 24 hours to prepare a thermally insulating sheet in which a coating containing polyvinyl alcohol and silica is formed on the side surface of the substrate. The composition for the second coating is in slurry form and, based on solids content, comprises 90 wt% silica and 10 wt% polyvinyl alcohol.

[0175] In the prepared thermal insulation sheet, the aerogel layer has a thickness of 2,000 μm, and the coating has a thickness of 100 μm.

[0176] Example 2

[0177] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the composition for the second coating was in the form of a slurry and, based on the solid content, included 90% by weight of alumina and 10% by weight of polyvinyl alcohol.

[0178] Example 3

[0179] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the composition for the first coating was in the form of a slurry and, based on the solid content, included 90% by weight of silica and 10% by weight of polyvinyl alcohol; and the composition for the second coating was in the form of a slurry and, based on the solid content, included 90% by weight of alumina and 10% by weight of polyvinyl alcohol.

[0180] Example 4

[0181] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the composition for the first coating was in the form of a slurry and, based on the solid content, included 90% by weight of silica and 10% by weight of polyvinyl alcohol.

[0182] Example 5

[0183] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the first substrate layer included a carbon fiber sheet (GSM: 80) with a thickness of 1 mm, and the second substrate layer included a carbon fiber sheet (GSM: 80) with a thickness of 1 mm.

[0184] Example 6

[0185] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the first substrate layer included a carbon fiber sheet (GSM: 120) with a thickness of 1.5 mm, and the second substrate layer included a carbon fiber sheet (GSM: 120) with a thickness of 1.5 mm.

[0186] Example 7

[0187] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the second substrate layer included a carbon fiber sheet (GSM: 80) with a thickness of 1 mm.

[0188] Example 8

[0189] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the aerogel layer had a thickness of 3,000 μm.

[0190] Example 9

[0191] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the first substrate layer included a glass fiber sheet (GSM: 150) with a thickness of 3 mm, and the second substrate layer included a glass fiber sheet (GSM: 150) with a thickness of 3 mm.

[0192] Example 10

[0193] The thermal insulation sheet was prepared in essentially the same manner as in Example 1, except that the first substrate layer included a carbon fiber sheet (GSM: 120) with a thickness of 2 mm, and the second substrate layer included a carbon fiber sheet (GSM: 120) with a thickness of 2 mm.

[0194] Comparative Example 1

[0195] The substrate was prepared in essentially the same manner as in Example 1, except that the first substrate layer and the second substrate layer comprised glass fiber sheets (GSM: 30).

[0196] Comparative Example 2

[0197] The substrate was prepared in essentially the same manner as in Example 1, except that the first substrate layer and the second substrate layer each comprised a glass fiber sheet (GSM: 600) with a thickness of 1.5 mm.

[0198] Comparative Example 3

[0199] The substrate was prepared in essentially the same manner as in Example 5, except that the first substrate layer and the second substrate layer each included carbon fiber sheets (GSM: 30).

[0200] Comparative Example 4

[0201] The substrate was prepared in essentially the same manner as in Example 5, except that the first substrate layer and the second substrate layer each included a carbon fiber sheet (GSM: 500) with a thickness of 1.5 mm.

[0202] Comparative Example 5

[0203] The substrate was prepared in essentially the same manner as in Example 1, except that mica sheets were used in each of the first and second substrate layers.

[0204] Comparative Example 6

[0205] The substrate was prepared in essentially the same manner as in Example 1, except that the aerogel layer had a thickness of 200 μm.

[0206] Comparative Example 7

[0207] The substrate was prepared in essentially the same manner as in Example 1, except that each of the first and second substrate layers had a thickness of 6.5 mm.

[0208] Comparative Example 8

[0209] The substrate was prepared in essentially the same manner as in Example 1, except that the aerogel layer had a thickness of 2 μm.

[0210] The physical properties of the thermal insulation sheets prepared in the examples and comparative examples were evaluated as follows.

[0211] (1) Grams per square meter (gsm): Glass fiber sheets or carbon fiber sheets are cut to prepare samples, and the length and width of the prepared samples are measured to calculate the area (m²). Subsequently, the weight (g) of the prepared samples is measured using a balance.

[0212] gsm = weight of sample (g) / area of ​​sample (m²) 2 )

[0213] (2) Thermal insulation properties (unit: °C): The prepared thermal insulation sheet was cut into sheets with a length of 232 mm and a width of 115 mm to prepare samples, and each sample was placed between a pair of opposing aluminum plates with a thickness of 1 mm. The samples were then placed on a hot press, with the upper plate of the hot press heated to 350 °C, while the lower plate was not heated and maintained at an initial temperature of 40 °C. A pressure of 20 kN was then applied to the lower plate of the hot press, and the temperature of the lower plate was measured after 11 minutes. The lower the temperature of the lower plate, the better the thermal insulation properties of the thermal insulation sheet.

[0214] (3) Dustproofness (unit: %): The prepared thermal insulation sheet was cut into length × width (12 inches × 12 inches) samples, and the weight of the samples was measured. The samples were vibrated under vibration conditions (frequency: 24 Hz / 3 mm, vibration time: 6 hours) using a vibration tester (ASTM C592-04), and the weight of the samples was measured. Subsequently, the weight reduction rate was evaluated using the following equation. The lower the weight reduction rate, the better the dustproofness of the thermal insulation sheet.

[0215] Weight reduction rate (%) = [(weight of sample before vibration) - (weight of sample after vibration)] / (weight of sample before vibration) × 100.

[0216] (4) Resistance to flame passage (unit: seconds): The prepared thermal insulation sheet was cut into 100 mm long and 70 mm wide pieces to prepare a sample, and a temperature sensor was mounted on the sample. A flame was applied to the surface of the sample using a torch capable of spraying flames, so that the surface temperature of the sample reached 1,200 °C. At this point, the time until the sample collapsed due to the appearance of cracks on the outside of the sample was measured. The longer this time, the better the resistance to flame passage.

[0217] (5) Compressibility (unit: %): The prepared thermal insulation sheet was cut into samples with a length of 232 mm and a width of 115 mm. The samples were placed between aluminum plates with a thickness of 1 mm, and the zero point was set using a UTM device. Subsequently, a compression test was performed by measuring the change in thickness when compressed at a compression rate of 0.02 mm / s from 0 MPa to 0.6 MPa. At this point, based on the thickness at 0 MPa, the thickness reduction rate at 0.55 MPa was used to represent compressibility. The higher the thickness reduction rate, the better the compressibility of the thermal insulation sheet.

[0218] Table 1

[0219]

[0220] As shown in Table 1 above, the thermal insulation sheet of the embodiment provides excellent thermal insulation properties, excellent dust resistance, excellent heat resistance and durability, and excellent compressibility.

[0221] On the other hand, the thermal insulation sheets of Comparative Examples 1 to 8 have poor dust resistance, poor heat resistance and poor durability, or poor compressibility.

[0222] Although the present invention has been described above with reference to some embodiments thereof, the present invention is not limited thereto. Therefore, it should be understood that those skilled in the art to which this invention pertains can make various changes and modifications within the scope of the claims, the detailed description of the invention, and the accompanying drawings, which also fall within the scope of the present invention.

Claims

1. A thermally insulating sheet for a rechargeable lithium battery, the thermally insulating sheet comprising: The substrate includes a first substrate layer, an aerogel-containing layer, and a second substrate layer that are sequentially laminated together. as well as A coating surrounding the substrate, Each of the first substrate layer and the second substrate layer includes one selected from the group consisting of: a glass fiber sheet of 70 gsm to 500 gsm; and a carbon fiber sheet of 50 gsm to 300 gsm. Each of the first substrate layer and the second substrate layer has a thickness of 300 μm to 5,000 μm. The aerogel layer has a thickness of 300 μm to 5,000 μm, and The aerogel is included in the aerogel-containing layer in an amount of 10% to 90% by weight.

2. The thermal insulation sheet according to claim 1, wherein the aerogel layer is a discontinuous layer separated from the first substrate layer.

3. The thermal insulation sheet according to claim 1, wherein the aerogel layer is a discontinuous layer separated from the second substrate layer.

4. The thermally insulating sheet according to claim 1, wherein the coating comprises a first coating on the upper and lower surfaces of the substrate; and a second coating on the side surface of the substrate, and The first coating and the second coating are made of the same or different inorganic layers.

5. The thermal insulation sheet according to claim 4, wherein each of the first coating and the second coating has a thickness of 1 μm to 500 μm.

6. The thermal insulation sheet according to claim 4, wherein the inorganic layer in the first coating and the second coating is a layer comprising at least one of silicon oxide and aluminum oxide.

7. The thermal insulation sheet according to claim 4, wherein the inorganic layer further comprises an adhesive.

8. The thermal insulation sheet according to claim 7, wherein the adhesive comprises at least one selected from polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, polyurethane, and polyester.

9. A rechargeable lithium battery module, comprising: Multiple battery cells are arranged facing each other; and The thermal insulating sheet for a rechargeable lithium battery according to any one of claims 1 to 8 is arranged between adjacent battery cells in the plurality of battery cells.

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