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

Abstract

The present disclosure relates to a thermal insulation sheet for a rechargeable lithium battery and a rechargeable lithium battery module including the same. The thermal insulation sheet for a rechargeable lithium battery includes: a base sheet including a first base layer and an aerogel-containing layer stacked together; and a member completely surrounding the outer surface of the base sheet. The aerogel-containing layer includes a binder including a polyvinyl alcohol-based binder, a fibrous support, and an aerogel, and the member includes one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, and a support.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0057050, filed on April 29, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to thermal insulation sheets for rechargeable lithium batteries and rechargeable lithium battery modules including thermal insulation sheets. Background Technology

[0004] With the increasing use of batteries in electronic devices (such as mobile phones, laptops, electric vehicles, etc.), the demand for rechargeable batteries with high energy density and high capacity (e.g., rechargeable lithium batteries) is gradually increasing. Therefore, improving the performance of rechargeable lithium batteries is beneficial.

[0005] Rechargeable lithium batteries typically include a positive electrode and a negative electrode (which contain active materials capable of inserting and deintercalating lithium ions), and generate electrical energy through oxidation and reduction reactions when lithium ions are inserted into and deintercalated from the positive and negative electrodes.

[0006] Multiple rechargeable lithium batteries may be included to form a rechargeable lithium battery module. In a rechargeable lithium battery module, reducing or blocking heat propagation and / or heat transfer between adjacent battery cells may be advantageous. Summary of the Invention

[0007] One example implementation includes a thermal insulation sheet for a rechargeable lithium battery, the thermal insulation sheet having desired or improved thermal insulation, flame retardancy, heat propagation delay, and compression properties.

[0008] Another example implementation includes a rechargeable lithium battery module that includes a thermal insulation sheet for the rechargeable lithium battery.

[0009] According to one example embodiment, a thermal insulation sheet for a rechargeable lithium battery includes: a base sheet comprising a stacked (e.g., sequentially stacked) first base layer and an aerogel-containing layer; and a component that completely or substantially completely surrounds the outer surface of the base sheet. The aerogel-containing layer comprises: an adhesive including a polyvinyl alcohol-based binder, a fiber support, and aerogel. The component comprises one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, as well as the support.

[0010] According to another example implementation, a rechargeable lithium battery module includes a plurality of battery cells facing each other and a thermal insulation sheet for the rechargeable lithium battery between the plurality of battery cells. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view of a thermal insulation sheet for a rechargeable lithium battery according to an example embodiment.

[0012] Figure 2 This is a cross-sectional view of a thermal insulation sheet for a rechargeable lithium battery according to another example embodiment.

[0013] Figure 3 This is a cross-sectional view of a thermal insulation sheet for a rechargeable lithium battery according to yet another example embodiment.

[0014] Figure 4 This is a perspective view of a rechargeable lithium battery module according to an example embodiment.

[0015] Figure 5 An exploded perspective view of a rechargeable lithium battery module according to an example embodiment.

[0016] Figure 6 A cross-sectional view of a battery cell according to an example embodiment is shown for illustrative purposes.

[0017] Figure 7 A view illustrating a battery pack according to an example implementation.

[0018] Figure 8 A view illustrating a battery pack according to an example implementation.

[0019] Figure 9 Views illustrating a vehicle body and body components according to an example embodiment.

[0020] Figure 10 Views illustrating a vehicle body and body components according to an example embodiment. Detailed Implementation

[0021] Hereinafter, exemplary embodiments of the present disclosure are described in detail. However, the embodiments are presented as examples, and the present disclosure is not limited thereto, and is limited only by the scope of the appended claims.

[0022] Unless otherwise stated herein, when a component (such as a layer, membrane, region, plate, etc.) is described as being disposed "on" another component, it includes not only cases where the component is "directly on" another component, but also cases where other components are present in between.

[0023] Unless otherwise stated herein, the singular may also include the plural. Additionally, unless otherwise stated, “A or B” may indicate “including A, including B, or including both A and B”.

[0024] In this specification, "combinations thereof" may refer to mixtures, stacks, complexes, copolymers, alloys, blends, and reaction products of the components.

[0025] When the terms “about” or “substantially” are used in conjunction with numerical values ​​in this specification, the relevant numerical values ​​are expected to include a tolerance of ±10% around the stated value. When a range is specified, the range includes all values ​​increasing in increments such as 0.1%.

[0026] In this document, "desired or improved compression characteristics" indicates, for example, a compression ratio of about 20% or greater, such as 25% or greater, 50% or greater, or in the range of 50% to 70%, as measured in the experimental examples below. Desired or improved compression characteristics increase battery stability by absorbing the pressure of adjacent battery cells during the cell degradation and expansion process.

[0027] Thermal insulation sheet (also known as thermal insulation pad) for rechargeable lithium batteries

[0028] A thermal insulation sheet for a rechargeable lithium battery according to an example embodiment includes: a base sheet comprising stacked (e.g., sequentially stacked) first base layer and an aerogel-containing layer; and a component that completely or substantially completely surrounds the outer surface of the base sheet. The aerogel-containing layer comprises: an adhesive including a polyvinyl alcohol-based binder, a fiber support, and aerogel. The component comprises one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, as well as the support.

[0029] According to one example embodiment, the base sheet may further include a second base layer stacked on the aerogel-containing layer. The first base layer and the second base layer may be the same or different.

[0030] The following describes in detail a thermal insulation sheet according to an example embodiment.

[0031] Basic films

[0032] The base sheet comprises a stacked (e.g., sequentially stacked) first base layer and an aerogel-containing layer.

[0033] The base sheet may include stacked (e.g., sequentially stacked) first base layer, aerogel-containing layer, and second base layer.

[0034] First Basic Layer

[0035] The first base layer can support the aerogel layer and the second base layer of the thermal insulation sheet.

[0036] The first base layer may be included in one or more layers of the thermal insulation sheet, that is, one, two or more layers.

[0037] The first base layer may be formed from or include at least one of the following: resin, metallic inorganic material, inorganic material other than metallic inorganic material and composite thereof; and may be or include at least one of membrane, thin film and sheet including membrane or thin film.

[0038] The resin may include, for example, one or more of the following: polyolefin resins (such as polyethylene or polypropylene); polystyrene resins; polyester resins (such as polyethylene terephthalate or polybutylene terephthalate); polyamide resins; and polyimide resins.

[0039] Metallic inorganic materials may include, for example, one or more of the following: copper, nickel, cobalt, iron, chromium, vanadium, palladium, ruthenium, rhodium, molybdenum, tungsten, iridium, silver, gold, and platinum. Depending on the requirements, metallic inorganic materials may undergo anti-corrosion treatment, insulation treatment, etc.

[0040] Inorganic materials other than metallic inorganic materials may include one or more of the following: calcium carbonate, talc, mica, glass wool, ceramic wool, carbon fiber, and aramid fiber.

[0041] According to one example implementation, the thermal insulation sheet may include an inorganic material other than a metallic inorganic material as a first base layer, for example, including a mica sheet as the first base layer. The mica sheet can be used to improve the thermal insulation and durability of the thermal insulation sheet.

[0042] The first base layer may have a thickness of about 10 μm to about 5000 μm, for example, 50 μm to 3000 μm or 100 μm to 1000 μm. Within the above range, the first base layer may be included in a thermally insulating sheet.

[0043] Aerogel layer

[0044] The aerogel layer may be or comprise a separate layer independent of the first base layer. In this document, "a separate layer independent of the first base layer" means that the aerogel layer is not formed in the first base layer by means of impregnation or the like, but rather that the first base layer and the aerogel layer are formed as completely separate or substantially completely separate and discontinuous layers.

[0045] The aerogel layer may be included in one or more layers of the thermal insulation sheet, that is, in one layer or two or more layers.

[0046] The aerogel-containing layer includes: an adhesive including a polyvinyl alcohol binder, a fiber support, and an aerogel.

[0047] The adhesive includes polyvinyl alcohol (PVA) adhesives. PVA adhesives are water-based and exhibit high solubility in water, as described below, allowing the formation of an aerogel-containing layer. Furthermore, for example, when the component is a coating, PVA adhesives can readily improve the compressive properties of the component. Additionally, by combining the fiber support and the aerogel, PVA adhesives facilitate the fabrication of an aerogel-containing layer, thereby improving processability.

[0048] According to one example embodiment, the amount of polyvinyl alcohol adhesive included may be about 95 wt% or more of the adhesive, for example, 95 wt% to 100 wt% or 100 wt%.

[0049] According to another example embodiment, the adhesive is or includes an organic water-based adhesive, and may further include one or more of cationic water-soluble polymers, anionic water-soluble polymers, and nonionic water-soluble polymers.

[0050] Cationic water-soluble polymers may be or include polymers having functional groups (such as at least one of amino, ammonium, phosphonium, thiophonium, and their salts), for example, polymers having amino groups. For example, cationic water-soluble polymers may include one or more of polyethyleneamine and polyamine.

[0051] Anionic water-soluble polymers may be or include polymers having functional groups (such as at least one of carboxylic acid groups, sulfonic acid groups, ester groups, phosphate ester groups, and their salts), for example, polymers having carboxylic acid groups. For example, anionic water-soluble polymers may be or include polymaleic acid.

[0052] Nonionic water-soluble polymers may include one or more of polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, polyurethane, and polyester. Nonionic water-soluble polymers may be or include water-dispersible polymers or water-based polymers.

[0053] According to one example embodiment, the binder may include one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, as well as a mixture of one or more of polyurethane and polyester. In this case, dispersion properties may be provided by one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone, and fire-resistant properties may be provided by one or more of polyurethane and polyester. For example, one or more of polyvinyl alcohol and polyurethane may be included.

[0054] According to one example embodiment, one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, and polyvinylpyrrolidone are in a weight ratio of one or more of polyurethane and polyester to about 1:1 to about 1:5, for example, 1:1 to 1:4 or 1:2 to 1:3. Within these ranges, the thermal insulation, dustproofing, fire resistance, and mechanical properties of the thermal insulation sheet can be improved.

[0055] According to one example embodiment, the adhesive is or includes an inorganic aqueous adhesive, and may further include one or more of sodium, potassium, or lithium silicate adhesives and phosphate adhesives.

[0056] The amount of the included adhesive, such as a polyvinyl alcohol adhesive, can range from about 0.5 wt% to about 20 wt% of the aerogel-containing layer. For example, the amount of the included adhesive can range from 2 wt% to 15 wt%, 5 wt% to 15 wt%, or 5 wt% to 10 wt% of the aerogel-containing layer. Within these ranges, the compression characteristics and dustproof properties of the thermal insulation sheet can be easily improved.

[0057] Fiber supports can help support the aerogel layer and improve the compressibility of the thermal insulation sheet.

[0058] The fiber support may be or include, for example, at least one of wool felt and chopped strand felt.

[0059] The fibers constituting the fiber support may include one or more of natural fibers, glass fibers (e.g., glass wool), carbon fibers, graphite fibers, mineral fibers, and polymer fibers. For example, the compressive properties of the fiber support can be further improved by using glass fibers.

[0060] Natural fibers may be or include fibers made from or including the following: hemp, jute, flax, coconut fiber, kenaf, and cellulose, or one or more of these. Mineral fibers may be or include fibers made from or including the following: basalt, wollastonite, alumina, silica, slag, and rock, or one or more of these. Polymer fibers may be or include fibers made from or including the following: nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamide-imide, polyesters (such as polyethylene terephthalate and polybutylene terephthalate), polyolefins (such as polyethylene and polypropylene), and basalt, or one or more of these.

[0061] For example, the fiber support may be or include glass wool.

[0062] The fibers in the fiber support may have an aspect ratio of about 1 or greater, for example, 1–20,000 or 2.5–10,000. Within these ranges, an aerogel layer can be firmly formed, and the durability of the thermal insulation sheet can be improved. In this document, “aspect ratio” refers to the ratio of the fiber length to the fiber diameter in the fiber support.

[0063] The fibers in the fiber support can have a length in the range of about 50 μm to about 2000 μm, for example, 50 μm to 1000 μm. Within this range, an aerogel layer can be firmly formed, and the durability of the thermal insulation sheet can be improved.

[0064] The fibers in the fiber support can have diameters ranging from about 0.1 μm to about 15 μm, for example, 0.1 μm to 20 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. In this document, when the fiber cross-section is circular, "diameter" indicates the diameter of the cross-section; and when the cross-section is not circular, "diameter" indicates the longest diameter of the cross-section.

[0065] The amount of fiber support that may be included is in the range of about 5 wt% to about 70 wt% of the aerogel layer. For example, the amount of fiber support that may be included is in the range of 10 wt% to 60 wt%, 10 wt% to 70 wt%, 10 wt% to 50 wt%, 25 wt% to 50 wt%, or 35 wt% to 50 wt% of the aerogel layer. Within these ranges, the flexibility and durability of the thermal insulation sheet can be easily improved.

[0066] Aerogels can provide thermal insulation for aerogel-containing layers.

[0067] According to one example embodiment, the aerogel may have a density of approximately 500m. 2 / g~approximately 1000m 2 Specific surface area in the range of / g. For example, the specific surface area can be 500m². 2 / g~950m 2 / g、550m 2 / g~950m 2 / g or 600m 2 / g~900m 2 Within the range of / g, heat transfer and thermal propagation between multiple battery cells can be easily reduced or prevented. In this paper, "specific surface area" can refer to the specific surface area based on Brunol-Emmett-Taylor (BET) specific surface area analysis, i.e., BET specific surface area.

[0068] According to one example embodiment, the aerogel may have an average particle size in the range of about 5 μm to about 200 μm. For example, the aerogel may have an average particle size in the range 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. In this document, "average particle size" refers to the average particle size D. 50 It refers to the diameter of particles that constitute 50% of the total volume in the particle size distribution. Average particle size D 50 The particle size distribution can be measured using methods known to those skilled in the art, such as using a particle size analyzer or using transmission electron microscopy or scanning electron microscopy. Alternatively, a measuring device can be used to measure the particle size distribution using dynamic light scattering, and the number of particles within each particle size range can be counted by performing data analysis, from which D can be calculated. 50 The value is used to obtain the average particle size D. 50 Value. Optionally, laser diffraction can be used to measure particle size distribution. When measuring average particle size by laser diffraction, for example, the average particle size D based on 50% of the particle size distribution in the measuring device can be calculated by dispersing the particles to be measured in a dispersion medium, then introducing the dispersion medium into a commercially available laser diffraction particle size measurement device (e.g., Microtrac MT 3000), and radiating ultrasound at approximately 28 kHz with an output power of 60 W. 50 .

[0069] According to one example embodiment, the aerogel can be hydrophobically treated. In this document, untreated aerogels are susceptible to moisture. In the process, moisture evaporates after slurry preparation to obtain a thermal insulation sheet; however, moisture evaporation takes time and increases the likelihood of cracks occurring in the thermal insulation sheet. Even after the thermal insulation sheet is manufactured, moisture absorption is highly probable, which can reduce reliability. Conventional methods known to those skilled in the art can be used to hydrophobically treat untreated aerogels.

[0070] The amount of aerogel that may be included is in the range of about 10 wt% to about 90 wt% of the aerogel-containing layer. For example, the amount of aerogel that may be included is in the range of 30 wt% to 70 wt%, 45 wt% to 65 wt%, 40 wt% to 60 wt%, or 40 wt% to 50 wt% of the aerogel-containing layer. Within the above ranges, the thermal insulation properties of the thermal insulation sheet can be increased.

[0071] According to one example embodiment, the total amount of the adhesive, fiber support, and aerogel, including the polyvinyl alcohol adhesive, may be about 95 wt% or more of the aerogel layer, for example, in the range of 95 wt% to 100 wt% or 99 wt% to 100 wt% of the aerogel layer, or 100 wt% of the aerogel layer.

[0072] The aerogel layer may further include one or more of a dispersant and a silane compound.

[0073] Dispersants can improve the dispersion of aerogel in compositions used for aerogel-containing layers, thereby ensuring the manufacture of aerogel-containing layers in which the fiber support and aerogel are substantially uniformly dispersed.

[0074] Dispersants may include one or more of surfactants and phosphate salts. Surfactants may include one or more of nonionic surfactants, anionic surfactants, and amphoteric surfactants. Surfactants may include one or more of natural surfactants (such as lecithin) and nonnatural surfactants (such as chemicals). Phosphate salts may be phosphate salts.

[0075] The amount of the dispersant may be in the range of about 0.1 wt% to about 6 wt% of the aerogel-containing layer. For example, the amount of the dispersant may be in the range of 0.1 wt% to 5 wt% or 0.1 wt% to 3 wt% of the aerogel-containing layer. Within the above ranges, compositions for aerogel-containing layers can be prepared at low cost and provide thermally insulating sheets with further improved thermal insulation, durability, and dust resistance.

[0076] According to one example embodiment, the binder:dispersant weight ratio can be from about 1:0.001 to about 1:0.7, for example, in the range of 1:0.001 to 1:0.67, 1:0.001 to 1:0.5, or 1:0.001 to 1:0.3. Within these ranges, when the binder and dispersant are included together, an aerogel-containing layer in which the aerogel is further substantially uniformly dispersed can be produced.

[0077] Silane compounds can improve the dispersibility of aerogels in aerogel-containing layers.

[0078] According to one example embodiment, silane compounds may include one or more of the following: alkyltrialkoxysilanes (such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, or octadecyltrimethoxysilane), epoxytrialkoxysilanes (such as glycidyltrioxymethylsilane), and unsaturated trialkoxysilanes (such as propyl 3-(trimethoxysilyl)methacrylate).

[0079] The aerogel layer may further include typical additives known to those skilled in the art. Additives include one or more of the following: wetting agents, emulsifiers, compatibilizers, viscosity modifiers, pH adjusters, stabilizers, antioxidants, acid or basic trapping agents, metal deactivators, defoamers, antistatic agents, tackifiers, adhesion promoters, binders, flame retardants, impact modifiers, pigments, dyes, colorants, and deodorants.

[0080] According to one example embodiment, the aerogel-containing layer may have a thickness in the range of about 100 μm to about 10,000 μm, for example, 500 μm to 5,000 μm or 1,000 μm to 3,000 μm. Within the above range, the aerogel-containing layer may be included in a thermally insulating sheet.

[0081] Aerogel-containing layers can be formed using compositions comprising a fiber support, aerogel, and a binder. The compositions for aerogel-containing layers may further comprise one or more of a dispersant, a silane compound, and an additive.

[0082] The method for manufacturing aerogel-containing layers is described in detail below.

[0083] Second Basic Layer

[0084] The second base layer can support the first base layer and the aerogel layer of the thermal insulation sheet.

[0085] The second base layer may be included in one or more layers of the thermal insulation sheet, that is, in one, two or more layers.

[0086] The second base layer may be stacked on the aerogel layer. The aerogel layer may be a separate layer independent of the second base layer. In this document, "a separate layer independent of the second base layer" means that the aerogel layer is not formed in the second base layer by means of impregnation or the like, but rather that the second base layer and the aerogel layer are formed as completely separate or substantially completely separate and discontinuous layers.

[0087] The second base layer may be formed of or include at least one of the following: resin, metallic inorganic material, inorganic material other than metallic inorganic material, and composites thereof; and may be or include at least one of membrane, thin film, and sheet comprising membrane or thin film. The resin, metallic inorganic material, and inorganic material other than metallic inorganic material are substantially the same as those described for the first base layer.

[0088] According to one example implementation, the thermal insulation sheet may include an inorganic material other than a metallic inorganic material as a second base layer, for example, including a mica sheet as the second base layer. The mica sheet can improve the thermal insulation and durability of the thermal insulation sheet.

[0089] The second base layer may have a thickness in the range of about 10 μm to about 5000 μm, for example, 50 μm to 3000 μm or 100 μm to 1000 μm. Within the above range, the second base layer may be included in the thermal insulation sheet.

[0090] member

[0091] The component completely or substantially completely surrounds the outer surface of the base plate. The component may fully contact, partially contact, or not contact the base plate.

[0092] The component may include one of a coating, a film, or a sheet. This is described in detail below.

[0093] The components include one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, as well as a support.

[0094] One or more of potassium nitrate, potassium carbonate, and potassium perchlorate exhibit flame-retardant and heat propagation delay effects in the thermal insulation sheet. In the event of a fire, this can impede or prevent the battery from igniting and delay heat propagation when sparks occur due to thermal runaway in adjacent cells, thereby increasing battery safety.

[0095] The amount of one or more of potassium nitrate, potassium carbonate, and potassium perchlorate included in the component may be in the range of about 0.1 wt% to about 50 wt%, for example, 0.5 wt% to 30 wt% or 5 wt% to 15 wt%. Within the above range, flame retardancy and heat propagation delay effects are provided, and one or more of potassium nitrate, potassium carbonate, and potassium perchlorate are prevented or inhibited from escaping from the component.

[0096] One or more of potassium nitrate, potassium carbonate, and potassium perchlorate are solid phases and, in addition to having a substantially true spherical shape, can be spherical, amorphous, plate-like, cubic, etc.

[0097] One or more of potassium nitrate, potassium carbonate, and potassium perchlorate may have an average particle size in the range of about 0.005 μm to about 10 μm, for example, 0.01 μm to 1 μm. Within this range, a coating can be easily formed.

[0098] The support structure allows for the stable retention of one or more of potassium nitrate, potassium carbonate, and potassium perchlorate within the component. Additionally, when the component is a coating, the support structure enables the coating to be firmly and reliably fixed to the base sheet. For example, when the component is a film or sheet, the support structure facilitates processability.

[0099] The amount of the support that may be included is in the range of about 50 wt% to about 99.9 wt% of the coating, for example, 70 wt% to 99.5 wt% or 85 wt% to 95 wt%. Within the above range, it can prevent or inhibit the shedding of one or more of potassium nitrate, potassium carbonate and potassium perchlorate from the component.

[0100] According to one example embodiment, the support may include an adhesive. The adhesive may include one or more of water-based and organic adhesives, provided that the adhesive does not affect the aforementioned effects of the thermal insulation sheet. The adhesive facilitates the formation of components in the form of a coating.

[0101] In one example implementation, the binder may include a water-dispersible binder. A water-dispersible binder can provide the effect of facilitating the preparation of a slurry for forming a component.

[0102] In one example embodiment, the adhesive may include one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, polyurethane, and polyimide. For example, the adhesive may be or include a water-dispersible polyurethane adhesive. Water-dispersible polyurethane adhesives facilitate the formation of coatings including one or more of potassium nitrate, potassium carbonate, and potassium perchlorate and may also help improve the compressibility of the thermal insulation sheet.

[0103] The amount of binder that may be included is in the range of about 50 wt% to about 99.9 wt% of the coating, for example, 70 wt% to 99.5 wt% or 85 wt% to 95 wt%. Within the above range, it can prevent or inhibit the shedding of one or more of potassium nitrate, potassium carbonate, and potassium perchlorate from the coating.

[0104] According to another example embodiment, the support includes a base resin and may include polyolefin resins (such as fiber-reinforced polymers, high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), and low-density polyethylene (LDPE)) and polyester resins (such as polyethylene terephthalate and polybutylene terephthalate).

[0105] According to one example implementation, the component may be or include a coating.

[0106] The coating contacts the base sheet and completely or substantially completely surrounds the outer surface of the base sheet.

[0107] For example, the coating can be formed on all or substantially all of the upper surfaces of the base sheet, the lower surface facing the upper surface, and the side surfaces connecting the upper and lower surfaces. Therefore, the coating can easily improve the compressive properties of the thermal insulation sheet. When the coating is formed only on the upper and lower surfaces of the base sheet, or only on two side surfaces of the base sheet, the compressive properties of the thermal insulation sheet can be poor.

[0108] According to one example implementation, the coating can be formed directly on the base sheet. In this document, "directly formed" means that no adhesive layer, bonding layer, etc., is formed between the base sheet and the coating.

[0109] The coating comprises one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, and a binder. The amount of one or more of potassium nitrate, potassium carbonate, and potassium perchlorate that may be included is in the range of about 0.1 wt% to about 50 wt% of the coating, for example, 0.5 wt% to 30 wt% or 5 wt% to 15 wt%, and the amount of binder that may be included is in the range of about 50 wt% to about 99.9 wt% of the coating, for example, 70 wt% to 99.5 wt% or 85 wt% to 95 wt%. Within the above ranges, one or more of potassium nitrate, potassium carbonate, and potassium perchlorate may be prevented or inhibited from escaping from the coating.

[0110] The coating may have a thickness in the range of about 1 μm to about 1000 μm, for example, 10 μm to 500 μm or 30 μm to 200 μm. Within this range, the coating may be included in thermal insulation sheets and rechargeable lithium battery modules.

[0111] According to another example implementation, the component may be or include a membrane or sheet.

[0112] The film or sheet may or may not contact the base sheet and may completely or substantially completely surround the outer surface of the base sheet. The film or sheet can be configured to encapsulate the base sheet, thereby improving flame retardancy and handleability.

[0113] The film or sheet may include one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, and a base resin. The amount of one or more of potassium nitrate, potassium carbonate, and potassium perchlorate that may be included is in the range of about 0.1 wt% to about 50 wt% of the film or sheet, for example, 0.5 wt% to 30 wt% or 5 wt% to 15 wt%, and the amount of base resin that may be included is in the range of about 50 wt% to about 99.9 wt%, for example, 70 wt% to 99.5 wt% or 85 wt% to 95 wt%. Within these ranges, one or more of potassium nitrate, potassium carbonate, and potassium perchlorate can be prevented or avoided from scattering from the component, and the packaging function of the base sheet can be easily implemented.

[0114] The film or sheet may have a thickness in the range of about 1 μm to about 1000 μm, for example, 10 μm to 500 μm or 30 μm to 200 μm. Within the above range, the film or sheet may be included in thermal insulation sheets and rechargeable lithium battery modules.

[0115] Figures 1-3 This is a cross-sectional view of a thermal insulation sheet for a rechargeable lithium battery according to an example embodiment.

[0116] refer to Figure 1The thermal insulation sheet for a rechargeable lithium battery may include: a base sheet 130A including a first base layer 110A, an aerogel layer 120 on the first base layer 110A; and a coating 140 that completely or substantially completely surrounds the outer surface of the base sheet 130A.

[0117] refer to Figure 2 The thermal insulation sheet for a rechargeable lithium battery may include: a base sheet 130B comprising a first base layer 110A, a second base layer 110B facing the first base layer 110A, an aerogel layer 120 stacked between the first base layer 110A and the second base layer 110B; and a coating 140 that completely or substantially completely surrounds the outer surface of the base sheet 130B.

[0118] refer to Figure 3 The thermal insulation sheet for a rechargeable lithium battery may include: a base sheet 130B comprising a first base layer 110A, a second base layer 110B facing the first base layer 110A, an aerogel-containing layer 120 stacked between the first base layer 110A and the second base layer 110B; and a film or sheet 150 completely or substantially completely surrounding the outer surface of the base sheet 130B. A vacuum region 160 may or may not exist between the base sheet 130B and the film or sheet 150.

[0119] The following describes a method for manufacturing a thermally insulating sheet according to an example embodiment.

[0120] According to one example embodiment, a method of manufacturing a thermal insulation sheet may include preparing a composition for an aerogel-containing layer comprising a fiber support, an aerogel, and an adhesive; manufacturing a base sheet by coating a first base layer with the composition for the aerogel-containing layer and drying the composition coated on the first base layer; and forming a coating on the outer surface of the base sheet.

[0121] According to another example embodiment, a method of manufacturing a thermal insulation sheet may include preparing a composition for an aerogel-containing layer comprising a fiber support, an aerogel, and an adhesive; manufacturing a base sheet by coating a first base layer with the composition for the aerogel-containing layer and drying the composition coated on the first base layer; and packaging the base sheet with a film or sheet.

[0122] The composition for the aerogel-containing layer includes a fiber support, an aerogel, and a binder. The fiber support, aerogel, and binder are essentially the same as those described above.

[0123] Compositions for use with aerogel layers may further include one or more of dispersants, silane compounds, and additives.

[0124] Compositions used for aerogel-containing layers may further include a solvent.

[0125] Solvents may include one or more of polar solvents and non-polar solvents.

[0126] Polar solvents may include at least one of water, alcohol solvents, and combinations thereof. Water may include, for example, purified water, ultrapure water, or combinations thereof. Alcohol solvents may include, for example, one or more of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol, and glycerol.

[0127] Nonpolar solvents may include hydrocarbon solvents. For example, hydrocarbon solvents may include one or more of aliphatic hydrocarbon solvents (such as alkane solvents (e.g., hexane, pentane, and heptane)) and aromatic hydrocarbon solvents (such as toluene and benzene).

[0128] For example, the solvent may include water. Including water as a solvent can effectively reduce raw material costs and post-processing costs.

[0129] A solvent may be included such that the weight ratio of the solvent to the total solids content of the composition for the aerogel layer is in the range of about 1:1 to about 1:90. For example, the weight ratio of solvent to the total solids content of the composition for the aerogel layer may be in the range 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.

[0130] Compositions for aerogel-containing layers can be prepared using solvents, fiber supports, aerogels, and binders.

[0131] According to one example embodiment, preparing a composition for an aerogel-containing layer may include preparing a first mixed solution by mixing an adhesive and a solvent; preparing a second mixed solution by mixing an aerogel with the first mixed solution; and preparing a composition for an aerogel-containing layer by mixing a fiber support with the second mixed solution. During the preparation of the first mixed solution, dispersants, silane compounds, additives, etc., may be additionally mixed.

[0132] A mixer can be used to prepare each of the following: the first mixed solution, the second mixed solution, and the composition for the aerogel layer. Examples of mixers include planetary mixers, thinky mixers, etc.

[0133] A planetary mixer may include one or more types of planetary blades and one or more types of high-speed dispersing blades. The planetary blades and high-speed dispersing blades rotate continuously about their axes. The rotational speed can be expressed as revolutions per minute (rpm).

[0134] According to one example embodiment, the planetary mixer may include a first blade and a second blade with different axes of rotation. For example, the first blade may be a low-speed blade, and the second blade may be a high-speed blade. Hereinafter, low speed and high speed are relative rotational speeds. For example, the first blade may be an open blade, and the second blade may be a despair blade. The rotational speed of the first blade may be in the range, for example, about 10 rpm to about 100 rpm or 10 rpm to 60 rpm. The rotational speed of the second blade may be in the range of 100 rpm to 2000 rpm.

[0135] According to one example implementation, a second base layer may be additionally stacked on the composition applied for the aerogel layer prior to drying.

[0136] An aerogel layer can be prepared by applying a composition for the aerogel layer and then drying the composition. Drying can be performed at temperatures ranging from about 25°C to about 100°C, 45°C to 90°C, or 60°C to 85°C. Within these ranges, an aerogel layer with desired or improved mechanical strength can be formed without the use of separate adhesive components or adhesives, while simultaneously reducing or preventing peeling between the first base layer and the aerogel layer, and between the aerogel layer and the second base layer.

[0137] A coating can be made by applying a slurry for coating to the entire surface of a base sheet through coating, spraying, or other means, and then drying the slurry.

[0138] The slurry used for coating may further include aqueous or organic solvents to form a coating substantially uniformly.

[0139] Drying can be performed at temperatures ranging from approximately 25°C to approximately 100°C, 45°C to 90°C, or 60°C to 85°C. Within these ranges, an aerogel layer with desired or improved mechanical strength can be formed without the use of separate adhesive components or adhesives, while reducing or preventing peeling between the base sheet and the coating.

[0140] Rechargeable lithium battery module

[0141] Another example implementation includes a rechargeable lithium battery module comprising a plurality of battery cells facing each other and a thermal insulation sheet between the plurality of battery cells.

[0142] Figure 4 and Figure 5 These are perspective views and exploded perspective views of a rechargeable lithium battery module according to an example embodiment.

[0143] refer to Figure 4 and Figure 5A rechargeable lithium battery module may include a plurality of battery cells 100 facing each other and a thermal insulation sheet 200 between the plurality of battery cells 100.

[0144] The thermal insulation sheet 200 for a rechargeable lithium battery may have a plate shape. One surface of the thermal insulation sheet 200 may contact one surface of a battery cell 100, and the other surface of the thermal insulation sheet 200 opposite to one surface of the thermal insulation sheet 200 may contact one surface of another battery cell 100.

[0145] The battery cell 100 may include a housing 50 configured to house an electrode assembly including a positive electrode and a negative electrode (see [reference]). Figure 6 ), a cover plate 60 connected to the housing 50 to seal the housing 50, and positive electrode terminals 12 and negative electrode terminals 22 electrically connected to the positive and negative electrodes of the electrode assembly and protruding to the outside of the cover plate 60.

[0146] The positive electrode may include a positive electrode current collector and a layer of positive electrode active material on the positive electrode current collector. The positive electrode active material layer may include a positive electrode active material and may further include a binder and / or conductive additives.

[0147] The content of positive electrode active material can be in the range of about 90 wt% to about 99 wt% relative to 100 wt% of positive electrode active material layer, and the content of binder and conductive additive can each be about 0.5 wt% to about 5 wt% relative to 100 wt% of positive electrode active material layer.

[0148] Al foil may be used as the positive electrode current collector, but the positive electrode current collector is not limited to this.

[0149] As a positive electrode active material, it may include compounds capable of reversibly inserting and de-intercalating lithium (lithiation-intercalated compounds). For example, it may include one or more composite oxides of lithium and metals (such as or including at least one of cobalt, manganese, nickel and combinations thereof).

[0150] The composite oxide may be or include lithium transition metal composite oxides. Examples of composite oxides may include at least one of lithium nickel oxides, lithium cobalt oxides, lithium manganese oxides, lithium iron phosphate compounds, cobalt-free nickel manganese oxides, and combinations thereof.

[0151] As an example, a compound represented by any of the following chemical formulas may be included as a complex oxide. 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-bX 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 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 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).

[0152] In the above chemical formulas, A is or includes at least one of Ni, Co, Mn, and combinations thereof; X is or includes at least one of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, rare earth elements, and combinations thereof; D is or includes at least one of O, F, S, P, and combinations thereof; G is or includes at least one of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, and combinations thereof; and L1 is or includes at least one of Mn, Al, and combinations thereof.

[0153] The negative electrode includes a negative electrode current collector and a negative electrode active material layer located on the negative electrode current collector. The negative electrode active material layer may include a negative electrode active material, and further includes a binder and / or a conductive additive.

[0154] For example, the negative electrode active material layer may include about 90 wt% to about 99.5 wt% of the negative electrode active material, about 0.5 wt% to about 5 wt% of the binder, and about 0 wt% to about 5 wt% of the conductive additive.

[0155] The negative electrode active material includes at least one of a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, a lithium metal alloy, a material capable of doping and dedoping lithium, and a transition metal oxide.

[0156] The material capable of reversibly intercalating / deintercalating lithium ions is a carbon-based negative electrode active material, and may include, for example, at least one of crystalline carbon, amorphous carbon, and combinations thereof. Examples of crystalline carbon may include graphite (such as natural graphite or artificial graphite), and examples of amorphous carbon may include at least one of soft carbon, hard carbon, mesophase pitch carbide, and calcined coke.

[0157] At least one of a Si-based negative electrode active material and a Sn-based negative electrode active material may be included as the material capable of doping and dedoping lithium. The Si-based negative electrode active material may be or include silicon, a silicon-carbon composite, SiO x (0 < x ≤ 2), a Si-based alloy, and combinations thereof.

[0158] The silicon-carbon composite may be or include a composite of silicon and amorphous carbon. According to one exemplary embodiment, the silicon-carbon composite may have a form including silicon particles and an amorphous carbon coating coated on the surface of the silicon particles.

[0159] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include: a core including crystalline carbon and silicon particles, and an amorphous carbon coating located on the surface of the core.

[0160] A non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof may be included as the binder. When an aqueous binder is included as the binder in the negative electrode active material layer, a cellulose-based compound capable of imparting viscosity may be further included.

[0161] As the negative electrode current collector, at least one of a copper foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foam, a copper foam, a polymer substrate coated with a conductive metal, and combinations thereof may be included.

[0162] The electrolyte for a rechargeable lithium battery includes a non-aqueous organic solvent and a lithium salt.

[0163] Non-aqueous organic solvents are configured such that ions participating in the electrochemical reactions of the battery can pass through the medium in which they move.

[0164] The non-aqueous organic solvent may be or include at least one of carbonate solvents, ester solvents, ether solvents, ketone solvents, alcohol solvents, aprotic solvents, and combinations thereof. It may include only any one of the above as a non-aqueous organic solvent, or it may be mixed and include two or more of the above as non-aqueous organic solvents.

[0165] For example, when carbonate solvents are included, cyclic carbonates and chain carbonates can be mixed.

[0166] Depending on the type of rechargeable lithium battery, a separator may be present between the positive and negative electrodes. It may include at least one of polyethylene, polypropylene, and polyvinylidene fluoride separators, or two or more multilayer films thereof as the separator.

[0167] The diaphragm may include a porous substrate and a coating on one or both surfaces of the porous substrate, and may include organic materials, inorganic materials, or combinations thereof.

[0168] Organic materials may include at least one of polyvinylidene fluoride polymers and (meth)acrylic acid polymers.

[0169] Inorganic materials may include inorganic particles, such as or including at least one of Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but are not limited thereto.

[0170] Organic and inorganic materials can be mixed in a single coating, or can be in the form of a coating that includes organic materials and a coating that includes inorganic materials stacked together.

[0171] Figure 6 A cross-sectional view of a battery cell 100 according to an example embodiment is shown for illustrative purposes.

[0172] refer to Figure 6 The battery cell 100 may include: an electrode assembly 40 including 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 for housing 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.

[0173] A rechargeable lithium battery module according to one example embodiment may be applicable to, for example, vehicles, mobile phones and / or various other forms of electronic devices, but this disclosure is not limited thereto.

[0174] The rechargeable lithium battery module according to the above example embodiments may be included in the manufactured battery pack.

[0175] Figure 7 A view illustrating a battery pack according to an example implementation.

[0176] Figure 8 A view illustrating a battery pack according to an example implementation.

[0177] A battery pack 2000 according to one example embodiment includes a kit of multiple electrically connected independent rechargeable lithium battery modules and a packaging housing that houses the rechargeable lithium battery modules. In the accompanying drawings, for ease of explanation, the description of components (such as buses, cooling units, external terminals, etc.) for the electrical connections of the rechargeable lithium battery modules has been omitted.

[0178] For example, battery pack 2000 may include multiple battery modules 1000 (e.g., including those referenced above). Figure 5 The description includes a rechargeable lithium-ion battery module and a packaging housing 2100 for housing the battery module 1000. For example, the packaging housing 2100 may include a first packaging housing 2101 and a second packaging housing 2102 connected to each other in a direction facing each other, with multiple battery modules 1000 inserted therebetween. The multiple battery modules 1000 may be electrically connected to each other using a bus 2200, or the multiple battery modules 1000 may be electrically connected in series or in parallel, or by a combination of series and parallel connections, to obtain the required electrical output.

[0179] Figure 9 Views illustrating a vehicle body and body components according to an example embodiment.

[0180] Figure 10 Views illustrating a vehicle body and body components according to an example embodiment.

[0181] The above reference Figure 7 and Figure 8 The battery pack 2000 described according to one example embodiment can be installed in a vehicle 3000. For example, the vehicle 3000 can be an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle 3000 can be, for example, a four-wheeled vehicle or a two-wheeled vehicle, or another type of vehicle.

[0182] like Figure 9 and Figure 10As illustrated herein, a vehicle 3000 according to an exemplary embodiment of the present disclosure includes a battery module 1000 and / or a battery pack 2000 including the battery module 1000. 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 exemplary embodiment of the present disclosure.

[0183] The following describes embodiments and comparative examples of the present disclosure. However, the following embodiments are merely implementations of the present disclosure, and the present disclosure is not limited to the following embodiments.

[0184] Example 1

[0185] Preparation of compositions containing aerogel layers

[0186] A first mixed solution was prepared by adding polyvinyl alcohol (Sigma Aldrich, PVA) as a binder to ultrapure water as a solvent, and the first mixed solution was mixed sequentially with an open blade at 30 rpm and with a despa blade at 700 rpm. Aerogel (BET specific surface area: 800 m²) was added to the first mixed solution. 2 A second mixed solution was prepared by mixing glass wool (g) at 70 rpm with an open blade and then at 1500 rpm with a despa blade. A composition for an aerogel-containing layer was prepared by adding glass wool, as a fiber support, to the second mixed solution and mixing the composition at 30 rpm with an open blade and then at 1200 rpm with a despa blade. A planetary mixer (D&Tech, PT-005) was used for mixing.

[0187] The prepared composition for the aerogel-containing layer is in the form of a slurry, and based on the solid content, the composition for the aerogel-containing layer comprises 45 wt% aerogel, 45 wt% glass wool, and 10 wt% polyvinyl alcohol.

[0188] Manufacturing of thermal insulation sheets

[0189] The prepared composition for the aerogel layer was applied to a 0.1 mm thick mica sheet as the first base layer, and a 0.1 mm thick mica sheet as the second base layer was stacked on top of the composition for the aerogel layer and coated using a roller coating method. Then, by drying the stack at 60°C for 24 hours, a base sheet was manufactured by sequentially stacking mica sheet / aerogel layer (thickness: 2 mm) / mica sheet.

[0190] A composition for coating is prepared by adding a water-dispersible polyurethane adhesive as a binder to ultrapure water as a solvent and mixing the composition with potassium nitrate. Such a thermal insulation sheet is manufactured by spraying the prepared composition for coating onto the outermost surface of a base sheet and drying the coating at 60°C for 24 hours, wherein a coating comprising a polyurethane adhesive and potassium nitrate is formed on the entire outer surface, including the upper, lower, and side surfaces of the base sheet.

[0191] The composition used for coating is in the form of a slurry and, based on solids content, includes 5 wt% potassium nitrate and 95 wt% water-dispersible polyurethane binder.

[0192] The thickness of the aerogel layer in the manufactured thermal insulation sheet is 2 mm, and the thickness of the coating is 100 μm.

[0193] Example 2

[0194] The base sheet was manufactured in essentially the same manner as in Example 1.

[0195] A composition for coating was prepared by adding a water-dispersible polyurethane binder as an adhesive to ultrapure water as a solvent and mixing the binder with potassium nitrate. Such a thermal insulation sheet was manufactured by spray-coating the prepared composition for coating onto the outermost surface of a base sheet and drying the coating at 60°C for 24 hours, wherein a coating comprising the polyurethane binder and potassium nitrate was formed on the entire outer surface, including the upper, lower, and side surfaces of the base sheet. The composition for coating was in slurry form and, based on solids content, included 15 wt% potassium nitrate and 85 wt% water-dispersible polyurethane binder. The thickness of the aerogel-containing layer in the manufactured thermal insulation sheet was 2 mm, and the thickness of the coating was 100 μm.

[0196] Example 3

[0197] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that instead of a coating comprising 5 wt% potassium nitrate and 95 wt% water-dispersible polyurethane binder, a coating comprising 5 wt% potassium carbonate and 95 wt% water-dispersible polyurethane binder was formed.

[0198] Example 4

[0199] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that instead of a coating comprising 5 wt% potassium nitrate and 95 wt% water-dispersible polyurethane adhesive, a coating comprising 5 wt% potassium perchlorate and 95 wt% water-dispersible polyurethane adhesive was formed.

[0200] Example 5

[0201] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, the composition for the aerogel-containing layer was changed to include 60 wt% aerogel, 25 wt% glass wool, and 15 wt% polyvinyl alcohol based on solid content.

[0202] Example 6

[0203] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, the composition for the aerogel-containing layer was changed to include 65 wt% aerogel, 25 wt% glass wool, and 10 wt% polyvinyl alcohol based on solid content.

[0204] Example 7

[0205] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, the composition for the aerogel-containing layer was changed to include 45 wt% aerogel, 50 wt% glass wool, and 5 wt% polyvinyl alcohol based on solid content.

[0206] Comparative Example 1

[0207] The base sheet is manufactured in essentially the same manner as in Example 1. The manufactured base sheet serves as a thermally insulating sheet without forming a coating.

[0208] Comparative Example 2

[0209] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, the coating was formed solely from a water-dispersible polyurethane binder without the use of potassium nitrate.

[0210] Comparative Example 3

[0211] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, a water-dispersible polyurethane (PU) binder was included in the composition for the aerogel layer instead of polyvinyl alcohol.

[0212] Comparative Example 4

[0213] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, a coating consisting of a water-dispersible polyurethane adhesive and potassium nitrate was formed only on the upper and lower surfaces of the base sheet, while no coating was formed on its two side surfaces.

[0214] Comparative Example 5

[0215] The thermal insulation sheet was manufactured in essentially the same manner as in Example 1, except that in Example 1, a coating consisting of a water-dispersible polyurethane adhesive and potassium nitrate was formed only on the two sides of the base sheet, while no coating was formed on its upper and lower surfaces.

[0216] Example 8

[0217] The base sheet was manufactured in essentially the same manner as in Example 1. The thermal insulation sheet was manufactured by packaging the base sheet with a fiber-reinforced polymer sheet comprising 10 wt% potassium nitrate.

[0218] Example 9

[0219] The base sheet was manufactured in essentially the same manner as in Example 1. The thermal insulation sheet was manufactured by packaging the base sheet with a high-density polyethylene film containing 10 wt% potassium nitrate.

[0220] The following physical properties were evaluated for the thermal insulation sheets manufactured in the examples and comparative examples.

[0221] (1) Thermal insulation (unit: seconds): Samples were prepared by cutting manufactured thermal insulation sheets into pieces 232 mm long and 115 mm wide. Each thermal insulation sheet sample was placed between a pair of 0.5 T thick copper plates facing each other and placed on a hot press. The upper plate of the hot press was heated to 600 °C, while the lower plate was kept at its initial temperature of 40 °C without heating. Then, while applying a pressure of 3500 kgf to the lower plate of the hot press, the time it took for the plate temperature to reach 300 °C was measured. The longer the measurement time, the better the insulation.

[0222] (2) Flame retardancy (unit: seconds): Samples were prepared by cutting the manufactured thermal insulation sheet into pieces 50 mm wide and 80 mm long. A miniature torch was installed 5 cm away from the sample, and a flame was radiated from the torch for 1 minute, after which the torch was removed. The thermal insulation sheet was then checked for ignition. If the thermal insulation sheet was ignited, the time required for the flame to extinguish was measured. The shorter the time, the better the flame retardancy.

[0223] (3) Compression ratio (unit: %): Samples were prepared by cutting the manufactured thermal insulation sheet into pieces 232 mm long and 115 mm wide. The sample was inserted between two 1 T thick aluminum plates by setting a zero point, and then the compression ratio was measured using a UTM device at a compression rate of 0.02 mm / sec from 0 kN to 80 kN. The higher the measured value, the higher the compression ratio.

[0224] Table 1

[0225]

[0226]

[0227] In Table 1, "-*" indicates no fire and "-" indicates "not applicable".

[0228] As shown in Table 1, the thermal insulation sheets of the embodiments have desired or improved thermal insulation, flame retardancy, heat propagation delay, and compression properties.

[0229] A thermal insulation sheet for a rechargeable lithium battery according to an example embodiment can reduce or suppress heat propagation and / or heat transfer in the battery module by providing desired or improved thermal insulation, thereby increasing the safety of the battery module. Additionally, the thermal insulation sheet for a rechargeable lithium battery can increase the lifespan of the rechargeable lithium battery module by providing flame retardancy and heat propagation delay effects. Furthermore, the thermal insulation sheet for a rechargeable lithium battery has desired or improved compressibility characteristics, which can reduce the pressure generated by repeated expansion of the rechargeable lithium battery during charging and discharging, thereby increasing the stability of the rechargeable lithium battery.

[0230] Although exemplary embodiments of the present disclosure have been described above, the present disclosure is not limited thereto and may be modified in any form within the scope of the claims, the specific embodiments of the present disclosure and the accompanying drawings, and such modifications also fall within the scope of the present disclosure.

Claims

1. A thermally insulating sheet for a rechargeable lithium battery, the thermally insulating sheet comprising: The base sheet consists of a first base layer and an aerogel layer stacked together; as well as The component completely surrounds the outer surface of the base sheet. The aerogel-containing layer comprises: a first adhesive including a polyvinyl alcohol binder, a fiber support, and an aerogel. The components include one or more of potassium nitrate, potassium carbonate, and potassium perchlorate, as well as a support.

2. The thermal insulation sheet according to claim 1, wherein the component is in complete contact, partially in contact, or not in contact with the base sheet.

3. The thermal insulation sheet according to claim 1, wherein the component comprises one of a coating, a film, or a sheet.

4. The thermal insulation sheet according to claim 1, wherein one or more of potassium nitrate, potassium carbonate and potassium perchlorate are included in the component in an amount ranging from 0.1 wt% to 50 wt%.

5. The thermal insulation sheet according to claim 1, wherein the support comprises one or more of a second adhesive and a base resin.

6. The thermal insulation sheet according to claim 5, wherein the second adhesive comprises one or more of polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, polyurethane, and polyimide.

7. The thermal insulation sheet according to claim 5, wherein the base resin comprises one or more of fiber-reinforced polymer, high-density polyethylene, linear low-density polyethylene, low-density polyethylene, polyethylene terephthalate, and polybutylene terephthalate.

8. The thermal insulation sheet according to claim 1, wherein the component comprises a coating, the coating comprising one or more of potassium nitrate, potassium carbonate and potassium perchlorate in an amount ranging from 0.1 wt% to 50 wt% of the coating, and a second binder in an amount ranging from 50 wt% to 99.9 wt% of the coating.

9. The thermal insulation sheet according to claim 1, wherein the component comprises a film or sheet, the film or sheet comprising one or more of potassium nitrate, potassium carbonate and potassium perchlorate in an amount ranging from 0.1 wt% to 50 wt% of the film or sheet, and a base resin in an amount ranging from 50 wt% to 99.9 wt% of the film or sheet.

10. The thermal insulation sheet according to claim 1, wherein the amount of the polyvinyl alcohol adhesive is 95 wt% or more of the first adhesive.

11. The thermal insulation sheet according to claim 1, wherein the fiber support comprises glass wool.

12. The thermal insulation sheet according to claim 1, wherein the aerogel-containing layer comprises: The fiber support comprises, in an amount ranging from 5 wt% to 70 wt% of the aerogel-containing layer. The aerogel, in an amount ranging from 10 wt% to 90 wt% of the aerogel-containing layer, and The amount of the polyvinyl alcohol adhesive is in the range of 0.5 wt% to 20 wt% of the aerogel-containing layer.

13. The thermal insulation sheet according to claim 1, wherein the first base layer comprises a mica sheet.

14. The thermal insulation sheet according to claim 1, wherein the base sheet further comprises a second base layer.

15. A rechargeable lithium battery module, comprising: Multiple battery cells facing each other; as well as A thermal insulation sheet between the plurality of battery cells according to any one of claims 1 to 14.

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