Insulation composition for battery device, method for preparing the same, sheet formed using the same, and battery module comprising the same

Abstract

To provide a battery module having superior thermal insulation, along with fire resistance, flame retardancy, or non-flammability, for inhibiting heat propagation to adjacent cells due to thermal runaway of the battery, a method of manufacturing the battery module, and a battery pack including the battery module.SOLUTION: The present invention relates to a battery module including a plurality of cells, an insulation sheet between the plurality of cells, the insulation sheet having an upper surface and a lower surface disposed so as to face respective cells adjacent thereto, and a refractory layer formed on at least one edge surface between the upper and lower surfaces of the insulation sheet, wherein the refractory layer includes an inorganic binder. The present invention also relates to a method of manufacturing the battery module, and a battery pack including the battery module.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a battery module, a manufacturing method thereof, and a battery pack including the same. [Background technology]

[0002] Secondary batteries are power storage systems that provide excellent energy density by converting electrical energy into chemical energy and storing it. Unlike primary batteries, which cannot be recharged, secondary batteries can be recharged, and are widely used in IT devices such as smartphones, cellular phones, laptops, and tablet PCs. In recent years, interest in electric vehicles has increased to prevent environmental pollution, and high-capacity secondary batteries are being adopted for electric vehicles. Such secondary batteries are required to have characteristics such as high density, high output, and stability.

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

[0004] Therefore, conventionally, a plate material or an insulating resin plate is placed between the cells to insulate and heat the adjacent cells.

[0005] The above information disclosed in the Background of the Invention is intended to enhance the understanding of the background of the present invention only, and may therefore include information that does not constitute prior art. Summary of the Invention [Problem to be solved by the invention]

[0006] An embodiment provides a battery module having excellent heat insulation properties as well as fire resistance and flame retardancy or non-combustibility in order to suppress heat transfer to adjacent cells due to thermal runaway of a battery, a manufacturing method thereof, and a battery pack including the same. [Means for solving the problem]

[0007] One embodiment provides a battery module including a plurality of cells, insulating sheets provided between the plurality of cells and arranged such that their upper and lower surfaces face adjacent cells, respectively, and a fire-resistant layer formed on at least one surface of an edge side between the upper and lower surfaces of the insulating sheet, the fire-resistant layer including an inorganic binder.

[0008] The cell may be a secondary battery cell.

[0009] The heat insulating sheet may include a first substrate, a second substrate, and an aerogel layer disposed between the first substrate and the second substrate.

[0010] Each of the first substrate and the second substrate may include a resin, a metal, an inorganic material other than a metal, or a composite thereof.

[0011] The aerogel layer may include an aerogel, a fibrous support, and a functional material including a binder, a dispersant, or a combination thereof.

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

[0013] The fibrous support may be one or more fibers selected from the group consisting of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers.

[0014] The binder includes an aqueous polymer binder, and the aqueous polymer binder may be at least one selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

[0015] The dispersant may be one or more selected from the group consisting of surfactants and phosphate salts.

[0016] The aerogel layer may contain 10% by weight to 90% by weight of the aerogel, 5% by weight to 70% by weight of the fibrous support, and 0.5% by weight to 20% by weight of the functional material, based on the total amount of the aerogel layer.

[0017] The inorganic binder may be one or more selected from the group consisting of aluminates, silicates, phosphates, sulfates, and chlorides.

[0018] The inorganic binder may be at least one selected from the group consisting of general calcium aluminate, pure calcium aluminate, sodium silicate, potassium silicate, lithium silicate, sodium phosphate, potassium phosphate, magnesium phosphate, zinc phosphate, calcium phosphate, aluminum phosphate, iron phosphate, sodium dihydrogen phosphate, sodium tripolyphosphate, sodium hexametaphosphate, magnesium sulfate, aluminum sulfate, iron (III) sulfate, magnesium chloride, iron (III) chloride, and polyaluminum chloride.

[0019] The fire-resistant layer may be formed on an upper surface, upper and lower surfaces, or the entire side surface of the heat insulating sheet.

[0020] The thickness of the fireproof layer formed on an upper surface of the side of the heat insulating sheet may be 120% to 400% of the thickness of the fireproof layer formed on a lower surface.

[0021] The battery module may include an empty space other than the space in which the cells and the insulation sheet are arranged, and the fire-resistant layer may be formed to cover a side of the insulation sheet and part or all of the side of adjacent two cells in the empty space formed at the upper part of the battery module, and the fire-resistant layer may be formed so that the thickness of the center is thicker than the thickness of the edge portions on both sides.

[0022] Another embodiment provides a method for manufacturing a battery module, the method including: arranging a plurality of cells; arranging an insulating sheet between the plurality of cells such that an upper surface and a lower surface of the insulating sheet face an adjacent cell; and forming a fire-resistant layer on at least one surface of edge sides between the upper surface and the lower surface of the insulating sheet, the fire-resistant layer including an inorganic binder.

[0023] The step of forming the fire resistant layer may occur before or after placing the insulation sheet between the plurality of cells.

[0024] The step of forming the fireproof layer may be performed by any one or more of gap coating, dip coating, slot die coating, blade coating, dispensing, printing, brush coating, and porting using an inorganic binder solution dispersed in a solvent.

[0025] Yet another embodiment provides a battery pack including the battery module. Effect of the Invention

[0026] The battery module according to the present invention can suppress the propagation of heat and flames to adjacent cells due to thermal runaway of a cell.

[0027] In addition, the heat insulating sheet provided in the battery module according to the present invention has excellent compression performance, mechanical strength and dimensional stability in addition to heat insulating properties, and therefore can prevent the aerogel layer from falling off due to external impact, making it easy to work with and preventing contamination of the mechanism. [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 is a schematic diagram showing a structure of a battery module according to an embodiment. [Diagram 2] FIG. 1 is a schematic diagram showing a structure of a battery module according to an embodiment. [Diagram 3]FIG. 1 is a schematic diagram showing a structure of a battery module according to an embodiment. [Figure 4] FIG. 1 is a schematic diagram showing a structure of a battery module according to an embodiment. [Diagram 5] FIG. 1 is a schematic diagram showing a structure of a battery module according to an embodiment. [Figure 6] 1 is a schematic diagram showing a cross-sectional structure of a heat insulating sheet according to one embodiment. [Figure 7] 13 is a photograph showing the results of a fire resistance evaluation experiment. [Figure 8] 1 is a graph showing the results of thermal runaway delay evaluation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Although the present invention will be described in detail below so as to be easily understood by those skilled in the art, the present invention may be embodied in various different forms and should not be construed as being limited to the embodiments set forth herein.

[0030] A battery module according to one embodiment includes a plurality of cells, insulating sheets each provided between the plurality of cells and each arranged such that an upper surface and a lower surface face an adjacent cell, and a fire-resistant layer formed on one or more of the edge sides between the upper surface and the lower surface of the insulating sheet, and the fire-resistant layer may include an inorganic binder.

[0031] In the battery module according to one embodiment, the fireproof layer may be formed on at least one selected from an upper surface, a lower surface, a front surface, and a rear surface of the edge side of the insulation sheet. As a specific example, the fireproof layer may be formed on the upper surface, the upper and lower surfaces, or the entire side surface of the edge side of the insulation sheet. As a more specific example, the fireproof layer may be necessarily formed on the upper surface of the edge side of the insulation sheet.

[0032] In the battery module according to one embodiment, the fire-resistant layer may be formed by coating a part or all of a portion of the surface of the insulation sheet that does not face the cells and is exposed to the outside.

[0033] In the battery module according to an embodiment, the fireproof layer may be formed by further coating some or all of the cells adjacent to the insulation sheet.

[0034] The battery module having the above structure has excellent heat insulation properties, fire resistance and flame retardancy or non-combustibility, and can suppress the propagation of heat and flame to adjacent cells due to thermal runaway of a cell. In particular, when a heat insulating sheet is provided between cells for insulation in the past, the edge side of the heat insulating sheet is exposed to air, and heat or flame may be transmitted to the exposed side during thermal runaway. However, the battery module according to the embodiment has a fire-resistant layer, which can effectively suppress this. In addition, the heat insulating sheet has excellent compression performance, and can ensure mechanical strength and dimensional stability, and can prevent the aerogel layer from falling off due to external impact, thereby improving workability and preventing contamination of the mechanism.

[0035] In one embodiment, the cell may be a secondary battery cell. The secondary battery may be, for example, a lithium secondary battery. The lithium secondary battery may be manufactured in various forms, such as a lithium ion battery, an all-solid-state battery, or a lithium metal battery. For example, the lithium secondary battery may have a structure in which a positive electrode plate and a negative electrode plate, on which a positive electrode active material and a negative electrode active material are respectively applied, are arranged with a separator sandwiched therebetween, and are sealed in a battery case together with an electrolyte to form a secondary battery cell. Depending on the shape of the battery case to be formed, it may be classified into a cylindrical type, a rectangular type, or a pouch type, and a plurality of secondary battery cells are connected in series or parallel to form a battery module.

[0036] Such secondary batteries require high stability. For example, if the secondary batteries are overcharged, decomposition reactions of the positive electrode active material or electrolyte and other side reactions may occur, and these reactions may release heat, which may eventually lead to an explosion of the secondary battery cell.

[0037] In this regard, in the present invention, by placing an insulating sheet between each of the cells and providing a fire-resistant layer on the side of the insulating sheet, in addition to excellent insulation properties, the cell has fire resistance and flame retardancy or non-combustibility, and can suppress the spread of heat and flame to adjacent cells due to thermal runaway of a cell.

[0038] In this description, left / right refers to the drawing. For example, in a rectangular parallelepiped, if the left side is a first side, the right side can be a second side opposite to the first side.

[0039] 1 is a schematic diagram showing a part of a battery module according to one embodiment, which includes heat insulating sheets disposed between a plurality of cells, and a fireproof layer formed on the upper surface of the side of the heat insulating sheet. In this case, a flame generated in one cell can be prevented from moving from the upper part of the side of the heat insulating sheet to an open space in the battery module, and the flame can be effectively prevented from spreading to an adjacent cell.

[0040] Referring to FIG. 1, a battery module 100 according to an embodiment may include a plurality of cells 10 and may include heat insulating sheets 20 provided between the plurality of cells 10. Here, the heat insulating sheet 20 may be disposed such that an upper surface and a lower surface face the adjacent cell 10, respectively. Also, a fireproof layer 30 may be formed on an upper surface of the side surface of the heat insulating sheet 20. As a result, a battery module with improved safety can be provided by blocking a flame in advance in the event of thermal runaway of one cell and minimizing the spread of the flame to other cells, and further, a secondary battery pack including the secondary battery module can be provided.

[0041] In one embodiment, the fireproof layer may be formed on the upper and lower surfaces or the entire side of the heat insulation sheet, where the upper and lower surfaces may refer to surfaces formed on the upper and lower parts, respectively, based on the shape in which the heat insulation sheet is arranged.

[0042] For example, the fire-resistant layer may be formed on the entire side of the heat insulating sheet, which can effectively prevent a flame generated in one cell from traveling through the side of the heat insulating sheet to an open space in the battery module and from spreading to an adjacent cell.

[0043] As another example, the fireproof layer may be formed on both upper and lower opposing sides of the heat insulating sheet, which can minimize the installation of the fireproof layer and more effectively prevent a flame generated in one cell from traveling through the upper and lower parts of the side of the heat insulating sheet to an empty space in the battery module and from spreading to an adjacent cell.

[0044] FIG. 2 is a schematic diagram showing a portion of a battery module according to one embodiment, which includes insulation sheets disposed between a plurality of cells, and in which fireproof layers are formed on upper and lower surfaces of the insulation sheets.

[0045] 2, the battery module 100 may include a plurality of cells 10 and may include heat insulating sheets 20 provided between the plurality of cells 10. Here, the heat insulating sheets 12 may be disposed such that their upper and lower surfaces face the adjacent cells 10, respectively. Also, the heat insulating sheets 20 may include fire-resistant layers 30 formed on upper and lower surfaces among the side surfaces. As a result, a battery module with improved safety can be provided by blocking a flame in advance in the event of thermal runaway of one cell and minimizing the spread of the flame to other cells, and further, a secondary battery pack including the secondary battery module can be provided.

[0046] In one embodiment, when the fire-resistant layer is formed over the entire side of the insulation sheet, the fire-resistant layers formed on the front and rear sides are not shown in the cross-sectional view, and are represented as in Figure 2, so they are omitted from the illustration.

[0047] In one embodiment, the thickness of the fireproof layer formed on the upper side of the heat insulating sheet may be 120% to 400%, 150% to 350%, or 200% to 350% of the thickness of the fireproof layer formed on the lower side. Specifically, the thickness of the fireproof layer formed on the upper side of the heat insulating sheet may be 1.2 to 4 times, 1.5 to 3.5 times, or 2 to 3.5 times the thickness of the fireproof layer formed on the lower side. As described above, by controlling the thickness ratio of the fireproof layers formed on the upper and lower sides of the side of the heat insulating sheet, it is possible to effectively prevent a flame from moving upward and spreading during thermal runaway in one cell.

[0048] FIG. 3 is a schematic diagram showing a portion of a battery module according to one embodiment, which includes insulation sheets disposed between a plurality of cells, and in which fireproof layers are formed on upper and lower surfaces of the insulation sheets, with the thickness of the fireproof layer formed on the upper surface being thicker than the thickness of the fireproof layer formed on the lower surface.

[0049] Referring to FIG. 3, the battery module 100 may include a plurality of cells 10 and may include a heat insulating sheet 20 provided between each of the plurality of cells 10. Here, the heat insulating sheet 12 may be disposed such that an upper surface and a lower surface face the adjacent cell 10, respectively. Also, the heat insulating sheet 20 may include a fireproof layer 30 formed on upper and lower surfaces among its side surfaces, and the thickness of the fireproof layer formed on the upper surface may be thicker than the thickness of the fireproof layer formed on the lower surface. As a result, a battery module with improved safety can be provided by effectively blocking a flame moving upward during thermal runaway of one cell and minimizing the spread of the flame to other cells, and further, a secondary battery pack including the secondary battery module can be provided.

[0050] In one embodiment, the battery module includes an empty space other than the space in which the cells and the heat insulating sheet are arranged, and the fireproof layer is formed to cover a side of the heat insulating sheet and a part or all of the side of the adjacent two cells in the empty space formed in the upper part of the battery module, and the fireproof layer may be formed so that the thickness of the center is thicker than the thickness of the edge portions on both sides. For example, the fireproof layer may be formed in a trapezoidal or dome shape. When the fireproof layer is formed so that the thickness of the center is thicker than the thickness of the edge portions on both sides, the fireproof layer at the center shields heat and flame, and thus, when a thermal runaway occurs in a cell, the flame and heat transferred from a vent portion at the center of the cell in the planar direction to an adjacent cell is blocked, and further thermal runaway is delayed or prevented.

[0051] FIG. 4 is a schematic diagram showing a portion of a battery module including a heat insulating sheet disposed between a plurality of cells, and a fireproof layer formed on an upper surface of one of the sides of the heat insulating sheet, the fireproof layer being formed in a trapezoidal shape.

[0052] Referring to FIG. 4, the battery module 100 according to an embodiment may include a plurality of cells 10 and may include a heat insulating sheet 20 provided between each of the plurality of cells 10. Here, the heat insulating sheet 12 may be disposed such that an upper surface and a lower surface face the adjacent cell 10, respectively. In addition, the heat insulating sheet 20 may include a fireproof layer 30 formed on an upper surface of the side thereof, and the fireproof layer 30 may be formed in a trapezoidal shape with a thickness in the center being thicker than the thicknesses of the edges on both sides. In this case, the fireproof layer may also be formed on a lower surface of the side of the heat insulating sheet, and the fireproof layer formed on the lower surface may be formed to a thickness thinner than the fireproof layer formed on the upper surface. As a result, a battery module with improved safety can be provided by blocking a flame in advance when a thermal runaway occurs in one cell, thereby minimizing the spread of the flame to other cells, and a secondary battery pack including the secondary battery module can be provided.

[0053] FIG. 5 is a schematic diagram showing a portion of a battery module including a heat insulating sheet disposed between a plurality of cells, and a fireproof layer formed on an upper surface of one of the sides of the heat insulating sheet, the fireproof layer being formed in a dome shape.

[0054] Referring to FIG. 5, the battery module 100 according to an embodiment may include a plurality of cells 10 and may include a heat insulating sheet 20 provided between each of the plurality of cells 10. Here, the heat insulating sheet 12 may be disposed such that an upper surface and a lower surface face the adjacent cell 10, respectively. In addition, the heat insulating sheet 20 may include a fireproof layer 30 formed on an upper surface of the side thereof, and the fireproof layer 30 may be formed in a dome shape with a thickness at the center being thicker than the thicknesses of the edges on both sides. In this case, the fireproof layer may also be formed on a lower surface of the side of the heat insulating sheet, and the fireproof layer formed on the lower surface may be formed to a thickness thinner than the fireproof layer formed on the upper surface. As a result, a battery module with improved safety can be provided by blocking a flame in advance when a thermal runaway occurs in one cell, thereby minimizing the spread of the flame to other cells, and a secondary battery pack including the secondary battery module can be provided.

[0055] In one embodiment, the heat insulating sheet may include a first substrate, a second substrate, and an aerogel layer disposed between the first substrate and the second substrate, wherein the first substrate and the second substrate may form upper and lower surfaces of the heat insulating sheet, respectively, and may be disposed to face adjacent cells, and may include edge sides between the upper and lower surfaces of the heat insulating sheet.

[0056] FIG. 6 is a schematic diagram showing the structure of a heat insulating sheet according to one embodiment.

[0057] 6, the heat insulating sheet 20 may be formed in a structure including a first substrate 21, a second substrate 22, and an aerogel layer 23 provided between the first substrate 21 and the second substrate 22. Here, the first substrate 21 and the second substrate 22 may form the upper and lower surfaces of the heat insulating sheet 20, respectively, and may be disposed so as to face the adjacent cells 10.

[0058] The first and second substrates may be made of various materials such as resin, metal, inorganic material other than metal, or composites thereof, and the type of the substrate is not limited. The form of the substrate may be a film, thin film, sheet, or the like, and is not particularly limited.

[0059] The resin may be, for example, one or more selected from the group consisting of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0060] The metal may be, for example, one or more selected from the group consisting of copper, nickel, cobalt, iron, chromium, vanadium, palladium, ruthenium, rhodium, molybdenum, tungsten, iridium, silver, gold, and platinum. When using a substrate made of the above metal material, the substrate may be subjected to anti-corrosion treatment, insulation treatment, etc., as necessary.

[0061] The inorganic material may be one or more selected from the group consisting of calcium carbonate (CaCO3), talc, and mica.

[0062] As a specific example, the first substrate and the second substrate may include an inorganic material, and more specifically, may include mica, which can improve the heat insulation property and durability of the heat insulating sheet.

[0063] The aerogel layer may include an aerogel, a fibrous support, and a functional material including a binder, a dispersant, or a combination thereof.

[0064] In one embodiment, the aerogel has a BET specific surface area of ​​500 m 2 / g~1,000m 2 For example, the aerogel may have a BET specific surface area of ​​500 m 2 / g~950m 2 / g, 550m 2 / g~950m 2 / g, or 600m 2 / g~900m 2 By including an aerogel having a BET specific surface area value within the above range, it is possible to provide a heat insulating sheet that effectively prevents heat transfer and heat propagation between a plurality of cells.

[0065] The average particle size (D50) of the aerogel may be 5 μm to 200 μm, 10 μm to 100 μm, or 20 μm to 50 μm. By including aerogel having a particle size within the above range, the heat insulating properties can be improved and the heat transfer between multiple cells can be delayed.

[0066] The average particle size (D50) can be measured, for example, by a laser diffraction method or a scanning electron microscope (SEM) photograph, and the average particle size (D50) of the particles can be defined as the particle size at 50% of the particle size distribution (the particle size corresponding to 50% of the cumulative volume of the particle size distribution).

[0067] The content of the aerogel may be 10% by weight to 90% by weight, 30% by weight to 70% by weight, or 40% by weight to 60% by weight based on the total amount of the aerogel layer. When the battery insulation sheet contains the aerogel within the above range, the insulation property can be improved.

[0068] In one embodiment, the fibrous support is included in the aerogel layer, thereby improving the durability of the heat insulating sheet formed using the aerogel layer.

[0069] The fibrous support may include fibers used as supports for conventional heat insulating materials. For example, the fibrous support may be one or more selected from the group consisting of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers. As a specific example, the fibrous support may include glass fibers, but is not limited thereto.

[0070] The natural fibers may be, for example, one or more selected from the group consisting of hemp, jute, flax, coir, hemp, and cellulose.

[0071] The ceramic fibers may be one or more selected from the group consisting of silicon carbide, silicon nitride, boron nitride, and aluminum silicon carbide.

[0072] The mineral fibers may be, for example, mineral fibers comprising one or more selected from the group consisting of basalt, wollastonite, alumina, boron, quartz, silica, slag, and rock.

[0073] The polymer fiber may be, for example, one or more selected from the group consisting of nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamideimide, polyethyleneterephthalate, polybutyleneterephthalate, polyester, polyethylene (PE), and polypropylene (PP). As a specific example, the polymer fiber may be, but is not limited to, one or more selected from the group consisting of polyimide, polyamide, and polybenzimidazole.

[0074] The form of the fibrous support may be, for example, one or more selected from the group consisting of powder, wool, chop, felt, batting, and lofty batting, but is not limited thereto.

[0075] The average diameter of the fibrous support may be, for example, 0.1 μm to 20 μm, 0.1 μm to 15 μm, 0.1 μm to 5 μm, 1 μm to 15 μm, or 3 μm to 10 μm. By including a fibrous support having an average diameter within the above range, the structure of the aerogel layer can be made stronger, and the production cost can be reduced.

[0076] The average length of the fibrous support may be, for example, 50 μm to 1000 μm, 70 μm to 800 μm, or 100 μm to 600 μm. By including a fibrous support having an average length within the above range, the aerogel layer can be formed firmly and durability can be improved.

[0077] The content of the fibrous support may be 5% by weight to 70% by weight, 25% by weight to 60% by weight, or 30% by weight to 50% by weight, based on the total amount of the aerogel layer. When an aerogel layer containing a fibrous support within the above range is formed to produce a heat insulating sheet, durability can be improved.

[0078] In one embodiment, the binder may include a water-based polymer binder. For example, the water-based polymer binder may be at least one selected from the group consisting of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

[0079] The water-soluble polymer may be, for example, at least one selected from the group consisting of polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinylpyrrolidone, but is not limited thereto.

[0080] The anionic water-soluble polymer may be at least one selected from the group consisting of polymers having functional groups of carboxylic acid, sulfonic acid, sulfate, phosphate, and salts thereof. For example, the anionic water-soluble polymer may be a polymer having a carboxylic acid group, and a specific example thereof may include, but is not limited to, polymaleic acid.

[0081] The cationic water-soluble polymer may be at least one selected from the group consisting of polymers having functional groups such as amine, ammonium, phosphonium, sulfonium, and salts thereof. For example, the cationic water-soluble polymer may be a polymer having an amine group, and a specific example thereof may be at least one selected from the group consisting of polyethylene amine and polyamine, but is not limited thereto.

[0082] The water-dispersible polymer may be at least one selected from the group consisting of water-dispersible polyurethane and water-dispersible polyester, but is not limited thereto.

[0083] The binder may include a water-based polymer and a water-dispersible polymer, for example, a water-based polymer having binder properties as well as dispersing properties, and a water-dispersible polyurethane having fire-resistant properties, and a specific example thereof may include polyvinyl alcohol and a water-dispersible polyurethane.

[0084] The weight ratio of the aqueous polymer and the water-dispersible polymer may be 1:1 to 1:5, 1:1 to 1:4, or 1:2 to 1:3. By using the aqueous polymer and the water-dispersible polymer in combination within the weight ratio range, the heat insulation property, dust resistance, and compression property of the heat insulating sheet can be further improved as well as fire resistance and mechanical properties.

[0085] The content of the binder may be 0.5 wt% to 20 wt%, 2 wt% to 15 wt%, or 8 wt% to 15 wt% based on the total amount of the aerogel layer. When the battery insulation sheet is manufactured using an aerogel composition containing a binder within the above range, the dust characteristics of the battery insulation sheet can be improved.

[0086] The content of the binder may be 0.5% by weight to 20% by weight, 2% by weight to 15% by weight, or 8% by weight to 15% by weight, based on the total amount of the aerogel layer. A heat insulating sheet including an aerogel layer containing a binder within the above range may have improved dust characteristics.

[0087] In one embodiment, the dispersant may be at least one selected from the group consisting of surfactants and phosphate-based salts. Specific examples of the dispersant include, but are not limited to, at least one of nonionic surfactants, anionic surfactants, amphoteric surfactants, natural surfactants such as lecithin, and phosphates.

[0088] When the dispersant is further included, the fibrous support and the aerogel may be more uniformly dispersed in the aerogel layer.

[0089] The content of the dispersant may be 0.1% to 6% by weight, 0.1% to 5% by weight, or 0.1% to 3% by weight, based on the total weight of the aerogel layer. By including the dispersant within the above range, a battery insulation sheet having excellent heat insulation properties, compression properties, and dust resistance can be produced.

[0090] The binder and the dispersant may be included in a weight ratio of 1:0.001 to 1:0.67, 1:0.001 to 1:0.5, or 1:0.001 to 1:0.3. When the binder and the dispersant are used in combination in a weight ratio within this range, the aerogel may be more uniformly dispersed in the aerogel layer.

[0091] In one embodiment, the fibrous support may be contained in an amount of 5 wt % to 70 wt %, the aerogel in an amount of 10 wt % to 90 wt %, and the functional material in an amount of 0.5 wt % to 20 wt %, relative to the total amount of the aerogel layer.

[0092] As an example, the aerogel layer may contain, relative to the total amount of the aerogel layer, 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, and 2% by weight to 15% by weight of the binder.

[0093] Specifically, the aerogel layer may contain 30% to 50% by weight of the fibrous support, 40% to 60% by weight of the aerogel, and 8% to 15% by weight of the binder, based on the total amount of the aerogel layer. When the aerogel layer is formed within the above ranges, excellent heat insulation can be achieved and durability can be improved, the bonding strength between the fibrous support and the aerogel can be improved, and dust generation can be prevented.

[0094] As another example, the aerogel layer may contain, relative to the total amount of the aerogel layer, 25% by weight to 60% by weight of the fibrous support, 30% by weight to 70% by weight of the aerogel, 2% by weight to 15% by weight of the binder, and 0.1% by weight to 5% by weight of the dispersant.

[0095] Specifically, the aerogel layer may contain, relative to the total amount of the aerogel layer, 30% by weight to 50% by weight of the fibrous support, 40% by weight to 60% by weight of the aerogel, 5% by weight to 10% by weight of the binder, and 0.1% by weight to 3% by weight of the dispersant. When the aerogel layer is formed within the above ranges, the dispersibility of the aerogel is improved, excellent heat insulation is realized, and durability is improved at the same time, and the bonding force between the fibrous support and the aerogel is improved, thereby preventing the generation of dust.

[0096] The aerogel layer may have a form in which the surface of the fibrous support is coated with aerogel. In this case, the aerogel and the fibrous support are uniformly distributed, and the binding force between the aerogel and the fibrous support is high, so that the generation of dust due to the detachment of the aerogel can be reduced.

[0097] In one embodiment, the aerogel layer may be formed in a single layer structure or a multi-layer structure. When the aerogel layer is formed in a multi-layer structure, the aerogel layer may be formed in 2 to 10 layers, 2 to 7 layers, or 2 to 5 layers.

[0098] In one embodiment, the fire resistant layer may include or be composed of an inorganic binder.

[0099] The inorganic binder may be one or more selected from the group consisting of aluminates, silicates, phosphates, sulfates, and chlorides.

[0100] The aluminate may be at least one selected from the group consisting of general calcium aluminate and pure calcium aluminate.

[0101] The silicate may be at least one selected from the group consisting of sodium silicate, potassium silicate, and lithium silicate.

[0102] The phosphate may be one or more selected from the group consisting of sodium phosphate, potassium phosphate, magnesium phosphate, zinc phosphate, calcium phosphate, aluminum phosphate, iron phosphate, sodium dihydrogen phosphate, sodium tripolyphosphate, and sodium hexametaphosphate.

[0103] The sulfate may be one or more selected from the group consisting of magnesium sulfate, aluminum sulfate, and iron (III) sulfate.

[0104] The chloride may be one or more selected from the group consisting of magnesium chloride, iron(III) chloride, and polyaluminum chloride.

[0105] As a specific example, the inorganic binder may be one or more selected from the group consisting of calcium aluminate, sodium silicate, and aluminum phosphate. By including the inorganic binder, the fire resistance of the heat insulating sheet can be improved and flame propagation between cells can be prevented.

[0106] A manufacturing method for a battery module according to one embodiment may include arranging a plurality of cells, arranging an insulating sheet between the plurality of cells such that an upper surface and a lower surface of the insulating sheet face adjacent cells, and forming a fire-resistant layer on one or more surfaces of edge sides between the upper surface and the lower surface of the insulating sheet.

[0107] In an embodiment, the arrangement of the plurality of cells in the step of arranging the plurality of cells is not particularly limited, and the plurality of cells may be appropriately arranged depending on the type of the battery.

[0108] In one embodiment, a heat insulating sheet may be disposed between each of the plurality of cells. The heat insulating sheet may be disposed such that an upper surface and a lower surface face the adjacent cells.

[0109] The method for producing the insulating sheet may include forming a first substrate, applying an aerogel composition onto the first substrate, and forming a second substrate on the applied aerogel composition.

[0110] The first and second substrates may be as described above, and the size and shape of the substrate may be appropriately adjusted according to the cell structure.

[0111] The process of preparing the aerogel composition may include mixing a functional material, including a binder, a dispersant, or a combination thereof, with a solvent to produce a solvent mixture, mixing the solvent mixture and an aerogel to produce an aerogel mixture, and mixing the aerogel mixture and a fibrous support to produce an aerogel composition.

[0112] In the step of preparing the solvent mixture by mixing the functional material with the solvent, a binder may be mixed with the solvent, or a binder and a dispersant may be mixed with the solvent. In one embodiment, the solvent may be one or more selected from the group consisting of polar solvents and non-polar solvents. The polar solvent may include water, an alcohol-based solvent, or a combination thereof.

[0113] The water may include, for example, purified water, ultra-pure water, or a combination thereof.

[0114] The alcohol-based solvent may be, for example, one or more selected from the group consisting of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol, and glycerol, but is not limited thereto.

[0115] The non-polar solvent may include a hydrocarbon solvent, for example, one or more selected from the group consisting of hexane, pentane, heptane, toluene, and benzene, and more preferably, an alkane solvent such as hexane, or a mixture containing an alkane solvent, but is not limited thereto.

[0116] The solvent may include water. When water is used as the solvent, raw material costs and post-treatment costs can be effectively reduced. However, when water is used as the solvent, there is a problem that it is difficult to mix with the hydrophobic aerogel. In one embodiment, the aerogel is uniformly dispersed by controlling the mixing step design, mixing conditions, addition and amount of binder and dispersant, etc. When the aerogel is uniformly dispersed in the composition in this manner, a battery insulation sheet having excellent insulation properties, durability, and low dust properties can be formed with a thin thickness without using a large amount of binder.

[0117] The solvent may be contained in such a way that the weight ratio of the solvent to the total amount of solids in the aerogel composition is 1:1 to 1:90. For example, the weight ratio of the solvent to the total amount of solids in the aerogel composition may be 1:50 to 1:70, 1:20 to 1:30, or 1:2 to 1:10. By controlling the weight ratio of the solvent to the total amount of solids within the above range, the viscosity can be controlled to coat the aerogel layer.

[0118] The specific explanation regarding the binder and dispersant may be as described above.

[0119] In the step of preparing the aerogel mixture by mixing the solvent mixture and the aerogel, the specific description of the aerogel may be the same as that described above.

[0120] In the step of preparing an aerogel composition by mixing the aerogel mixture and the fibrous support, the specific description of the fibrous support may be as described above.

[0121] In one embodiment, the aerogel composition may further include a silane-based compound. The silane-based compound may be, for example, one or more selected from the group consisting of 3-(trimethoxysilyl)propylmethacrylate, methyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octadecyltrimethoxysilane, ethyltriethoxysilane, and 3-glycidoxypropyltrimethoxysilane. When the silane-based compound is further included, the dispersibility may be further improved.

[0122] In one embodiment, the aerogel composition may optionally further comprise additives such as wetting agents, emulsifiers, compatibilizers, viscosity modifiers, pH modifiers, stabilizers, antioxidants, acidic or basic scavengers, metal deactivators, antifoaming agents, antistatic agents, thickeners, adhesion improvers, binders, flame retardants, impact modifiers, pigments, dyes, colorants, deodorizers, and the like.

[0123] In each of the steps of preparing a solvent mixture by mixing a functional material including a binder, a dispersant, or a combination thereof with the solvent, preparing an aerogel mixture by mixing the solvent mixture and an aerogel powder, and preparing an aerogel composition by mixing the aerogel mixture and a fibrous support, a mixer may be used during mixing. For example, the mixer may include, but is not limited to, a planetary mixer and a thinky mixer.

[0124] As a specific example, a planetary mixer may be used to mix the solvent mixture and the aerogel powder. When the solvent mixture and the aerogel powder are mixed using the planetary mixer, the aerogel powder can be uniformly dispersed in the solvent.

[0125] The planetary mixer may be a device that can be used to mix or stir different materials to produce a homogenous mixture, and may include blades that are capable of planetary motion.

[0126] In one embodiment, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades. As a specific example, the planetary mixer may include one or more planetary blades and one or more high-speed dispersion blades.

[0127] The planetary blades and high speed dispersion blades rotate continuously about their axes, and the rotational speed may be expressed in units of rotations per minute (rpm).

[0128] In one embodiment, the planetary mixer may include a first blade and a second blade having different rotation axes. For example, the first blade may be a low-speed blade, and the second blade may be a high-speed blade. Here, low speed and high speed refer to the relative rotation speeds of the first blade and the second blade. As a specific example, the first blade may be an open blade, and the second blade may be a Despa blade.

[0129] The rotation speed of the first blade may be, for example, 10 rpm to 100 rpm, 10 rpm to 60, or 30 rpm to 70 rpm, and the rotation speed of the second blade may be, for example, 100 rpm to 2000 rpm, 100 rpm to 1000 rpm, 300 rpm to 1700 rpm, or 500 rpm to 1700 rpm.

[0130] When the functional material is mixed in the solvent, the rotation speed of the first blade may be 10 rpm to 60 rpm, 20 rpm to 50 rpm, or 30 rpm to 40 rpm, and the rotation speed of the second blade may be 300 rpm to 1700 rpm, 600 rpm to 1000 rpm, or 700 rpm to 800 rpm. By mixing the solvent and the functional material as described above, a solvent mixture in which the binder, dispersant, or a combination thereof is uniformly dispersed is prepared, and aerogel mixing in the subsequent step can be performed more easily.

[0131] When the solvent mixture and the aerogel powder are mixed, the rotation speed of the first blade of the mixer may be 30 rpm to 70 rpm, 40 rpm to 70 rpm, or 60 rpm to 70 rpm, and the rotation speed of the second blade may be 500 rpm to 1700 rpm, 600 rpm to 1600 rpm, or 800 rpm to 1500 rpm. By adding the aerogel powder to the solvent mixture and mixing it as described above, it is possible to prevent the aerogel powder from agglomerating with each other and induce uniform dispersion.

[0132] When the aerogel mixture and the fibrous support are mixed, the rotation speed of the first blade of the mixer may be 10 rpm to 60 rpm, 20 rpm to 50 rpm, or 30 rpm to 40 rpm, and the rotation speed of the second blade may be 300 rpm to 1700 rpm, 400 rpm to 1500 rpm, or 800 rpm to 1200 rpm. When the aerogel mixture and the fibrous support are mixed in this way, the air bubbles in the composition are removed, the viscosity is adjusted, and the fibrous support is easily dispersed between the uniformly dispersed aerogel, so that the aerogel may be present in the composition in a form in which the periphery of the fibrous support is covered by the aerogel. Here, a binder is present between the aerogel and the fibrous support, which can improve the binding force between the aerogel and the fibrous support.

[0133] By forming an insulating sheet using a method according to an embodiment, durability as well as insulating properties are improved, and dust generation due to the aerogel falling off during manufacturing the insulating sheet, installation inside an apparatus, or when external vibration occurs can be prevented.

[0134] In one embodiment, the step of forming a fireproof layer on any one or more of the edge sides between the upper and lower surfaces of the insulation sheet may be performed before or after placing the insulation sheet between the multiple cells.

[0135] For example, the step of forming the fireproof layer may be performed before the insulation sheet is disposed between the cells. In this case, after the insulation sheet is manufactured, a fireproof layer may be formed on at least one of the sides of the insulation sheet, and the insulation sheet with the fireproof layer formed thereon may be disposed between the cells.

[0136] The fire-resistant layer may be formed by a coating process of an inorganic binder solution dispersed in a solvent, such as gap coating, dip coating, slot die coating, blade coating, dispensing, printing, brush coating, or porting using molding. Specifically, the fire-resistant layer can be formed by coating the inorganic binder in a solution state dispersed in a solvent or the like on one or more of the sides of the heat insulating sheet, and drying the coating at room temperature or at a temperature of 40°C to 80°C within 24 hours.

[0137] As another example, the step of forming the fireproof layer may be performed after disposing the heat insulating sheet between the plurality of cells. In this case, the heat insulating sheet may be disposed between the plurality of cells, and the fireproof layer may be formed on one or more of the sides of the heat insulating sheet.

[0138] The fireproof layer may be formed by a solution process such as gap coating, dispensing, printing, brush coating, porting, etc. Specifically, an inorganic binder in a solution state dispersed in a solvent or the like is injected into one or more of the sides of the heat insulating sheet from a side portion of the heat insulating sheet exposed inside the battery module in which the plurality of cells and the heat insulating sheet are arranged, and dried at room temperature or a temperature of 40°C to 80°C within 24 hours to form the fireproof layer.

[0139] An embodiment includes a battery pack including the battery module. A plurality of battery modules may be disposed within the battery pack.

[0140] Specific examples of the present invention will be presented below. However, the examples described below are merely for the purpose of specifically illustrating or explaining the present invention, and the present invention should not be limited thereto. Furthermore, since the contents not described here can be sufficiently inferred by a person skilled in the art, the description thereof will be omitted.

[0141] (Battery module manufacturing) Example 1 1.Insulation sheet manufacturing Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) was added as a binder to ultrapure water as a solvent, and then mixed under conditions of an open blade of 30 rpm and a despa blade of 700 rpm to produce a solvent mixture. 2 Aerogel powder having a particle size of 1 / g was added and mixed at an open blade speed of 70 rpm and a Despa blade speed of 1500 rpm to produce an aerogel mixture. Glass wool was added to the aerogel mixture and mixed at an open blade speed of 30 rpm and a Despa blade speed of 1200 rpm to produce an aerogel composition. A planetary mixer (DN Tech, PT-005) was used for mixing.

[0142] The solid content of the prepared aerogel composition was confirmed to be 50 wt % aerogel, 40 wt % glass wool, and 10 wt % polyvinyl alcohol.

[0143] The aerogel composition prepared above was applied as a slurry onto a mica sheet (Famica, Muscovite) having a thickness of 0.1 mm, and then a mica sheet having a thickness of 0.1 mm was laminated in a sandwich type and coated by a roll rolling method. Then, the aerogel layer was formed by drying at 60°C for 24 hours, and a battery insulation sheet was manufactured. The total thickness of the manufactured battery insulation sheet was confirmed to be 1.38 mm.

[0144] 2.Refractory layer manufacturing A fireproof layer was formed on the upper surface of the heat insulating sheet by dispensing printing using calcium silicate as an inorganic binder, and the thickness of the fireproof layer was confirmed to be 0.3 mm.

[0145] 3. Battery module manufacturing A plurality of cells are arranged in a battery module, and heat insulating sheets each having a fire-resistant layer formed thereon are arranged between the plurality of cells.

[0146] Example 2 The same method as in Example 1 was used to prepare the inorganic binder, except that calcium aluminate was used instead of calcium silicate.

[0147] Example 3 The same method as in Example 1 was used to prepare the inorganic binder, except that aluminum phosphate was used instead of calcium silicate.

[0148] Example 4 The same method as in Example 1 was used to prepare the fireproof layer, except that the brush coating method was used instead of the dispensing printing method.

[0149] Example 5 The heat insulating sheet was produced in the same manner as in Example 1, except that a fireproof layer was formed on the upper and lower sides of the heat insulating sheet.

[0150] Example 6 The heat insulating sheet was produced in the same manner as in Example 1, except that a fire-resistant layer was formed on the entire side surface of the heat insulating sheet.

[0151] Example 7 In Example 1, fireproof layers were formed on the upper and lower sides of the side of the heat insulating sheet. The thickness of the fireproof layer formed on the upper side was adjusted to 0.7 mm, and the thickness of the fireproof layer formed on the lower side was adjusted to 0.3 mm. The heat insulating sheet was manufactured in the same manner as in Example 1, except that the thickness of the fireproof layer formed on the upper side was adjusted to 0.7 mm, and the thickness of the fireproof layer formed on the lower side was adjusted to 0.3 mm.

[0152] Example 8 1.Insulation sheet manufacturing Polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) was added as a binder to ultrapure water as a solvent, and then mixed under conditions of an open blade of 30 rpm and a despa blade of 700 rpm to produce a solvent mixture. 2Aerogel powder having a particle size of 1 / g was added and mixed at an open blade speed of 70 rpm and a Despa blade speed of 1500 rpm to produce an aerogel mixture. Glass wool was added to the aerogel mixture and mixed at an open blade speed of 30 rpm and a Despa blade speed of 1200 rpm to produce an aerogel composition. A planetary mixer (DN Tech, PT-005) was used for mixing.

[0153] The solid content of the prepared aerogel composition was confirmed to be 50 wt % aerogel, 40 wt % glass wool, and 10 wt % polyvinyl alcohol.

[0154] The aerogel composition prepared above was applied as a slurry onto a mica sheet (Famica, Muscovite) having a thickness of 0.1 mm, and then a mica sheet having a thickness of 0.1 mm was laminated in a sandwich type and coated by a roll rolling method. Then, the aerogel layer was formed by drying at 60°C for 24 hours, and a battery insulation sheet was manufactured. The total thickness of the manufactured battery insulation sheet was confirmed to be 1.38 mm.

[0155] 2. Battery module manufacturing A plurality of cells are arranged in a battery module, and a heat insulating sheet is arranged between each of the plurality of cells.

[0156] 3.Refractory layer manufacturing A trapezoidal molding was attached to cover the upper surface of the insulation sheet between the cells and a part of the side of the adjacent cell, and a fireproof layer was formed by injecting calcium silicate as an inorganic binder in a solution state and drying it. At this time, the thickness of the center of the fireproof layer was confirmed to be 0.7 mm, and the thickness of both edges was confirmed to be 0.5 mm.

[0157] Comparative Example 1 1. Aerogel Composition Preparation An aerogel composition was prepared by mixing ultrapure water as a solvent, polyvinyl alcohol (Sigma Aldrich, Poly(vinyl alcohol)) as a binder, and an aerogel with a BET value of 800 m2 / g. A planetary mixer (DN Tech, PT-005) was used for mixing.

[0158] The solid content of the prepared aerogel composition was confirmed to be 50 wt % aerogel, 40 wt % glass wool, and 10 wt % polyvinyl alcohol.

[0159] 2. Battery insulation sheet manufacturing The aerogel composition prepared above was applied as a slurry onto a 0.1 mm thick mica sheet (Famica, Muscovite), and then a 0.1 mm thick mica sheet was laminated in a sandwich type and coated by a roll rolling method. Then, the aerogel layer was formed by drying at 60°C for 24 hours to prepare a battery insulation sheet. The total thickness of the battery insulation sheet prepared was confirmed to be 1.38 mm.

[0160] (Experimental Example) Experimental example 1: Fire resistance evaluation Using the heat insulating sheets produced in the above Examples 1 to 8 and Comparative Example 1, fire resistance was evaluated.

[0161] Specifically, a gas ignition torch was used to irradiate the surface direction where the fireproof layer was formed for 10 minutes under conditions of an irradiation temperature of 1100±10°C and an irradiation distance of 5 cm or less, and then changes such as collapse of the fireproof layer and internal structure were observed. The side of the heat insulating sheet was sampled to a size of 20×60 mm, and a 3-point bending test was performed using a Universal Test Machine (UTM) to measure toughness, which indicates the energy storage value until the final breakdown / destruction of the sheet, to evaluate each heat insulating sheet, and the toughness measurements are shown in Table 1 below. Photographs of Examples 1, 4, and 8 and Comparative Example 1 after flame irradiation can be seen in FIG. 7.

[0162] [Table 1]

[0163] Referring to Table 1, it can be seen from Examples 1 to 3 that the toughness measurement results, which are the mechanical durability after flame irradiation, vary depending on the type of inorganic binder. As a result, it can be seen that when calcium silicate, calcium aluminate, and aluminum phosphate are used as inorganic binders, all of them have excellent fire resistance.

[0164] In addition, from Examples 1 and 4, the fire resistance evaluation results according to the fire resistance layer formation method were confirmed, and it was confirmed that the dispensing printing method formed a more uniform and dense fire resistance layer than the brush coating method, and showed better fire resistance.

[0165] In addition, it was confirmed from Example 5 that toughness is further improved when the fireproof layer is formed on the upper and lower surfaces of the side of the heat insulation sheet. In addition, in Example 6, the fireproof layer is formed on the entire side of the heat insulation sheet, and toughness is improved to some extent, but the degree of improvement is small and efficiency may be low. In addition, it was confirmed from Example 7 that toughness is further improved when the thickness of the fireproof layer formed on the upper surface is made thicker when the fireproof layer is formed on the upper and lower surfaces of the side of the heat insulation sheet.

[0166] In addition, from Example 8, it was confirmed that toughness can be effectively improved when the fire-resistant layer is formed in a trapezoidal shape so as to cover the upper surface of the insulation sheet and part of the side surface of the adjacent cell, even if the fire-resistant layer is formed on the upper and lower surfaces of the side surface of the insulation sheet.

[0167] On the other hand, in Comparative Example 1, which did not include a composite fireproof layer, it was confirmed that the fireproofing property was significantly reduced.

[0168] Fig. 7 shows internal photographs of the battery insulation sheets of Examples 1 to 4 and 8 and Comparative Example 1 after measuring fire resistance. As can be seen from Fig. 7, confirmation of the internal structure revealed that the fire resistance of the side portions of the insulation sheets in the examples was excellent due to the formation of a fire-resistant layer.

[0169] Specifically, it was confirmed that the fire resistance and structural fragility of the side portion of the heat insulating sheet was very poor in Comparative Example 1. In contrast, it was confirmed that Examples 1, 4, and 8 had excellent fire resistance and did not burn, and had excellent structural stability and heat insulation properties.

[0170] Experimental example 2: Thermal runaway delay evaluation Using the heat insulating sheets produced in the above Examples 1 to 8 and Comparative Example 1, a thermal runaway delay evaluation was carried out.

[0171] Specifically, using a simplified module device consisting of three rectangular cells, a thermal runaway test was performed on each thermal insulation sheet by artificially inducing thermal runaway by heating the hot wire pad attached to the detonation cell (heating 20°C / min) under the condition of a fastening pressure of 15kN for the thermal insulation sheet between the cells, and the thermal runaway delay time (s) was measured and shown in the following Table 2. In addition, the temperature change over time for Examples 1 and 4 and Comparative Example 1 is shown in Figure 8.

[0172] [Table 2]

[0173] Referring to Table 2, the thermal runaway delay evaluation results according to the type of inorganic binder can be seen from Examples 1 to 3. As a result, it was confirmed that when calcium silicate, calcium aluminate, and aluminum phosphate were used as the inorganic binder, they all had excellent thermal runaway delay effects.

[0174] In addition, the thermal runaway delay evaluation results according to the method of forming the fireproof layer can be confirmed from Examples 1 and 4, and it was confirmed that the thermal runaway delay effect is better when the fireproof layer is formed uniformly and densely by the dispensing method. On the other hand, from Figure 8, it can be confirmed that in Examples 1 and 4, by forming the fireproof layer, the temperature rise of the adjacent cells during thermal runaway does not appear immediately but is delayed, and it can be confirmed that the temperature rise during thermal runaway is further delayed in Example 1.

[0175] In addition, from Examples 1, 5 to 8, the thermal runaway delay evaluation results according to the position and shape of the fireproof layer were confirmed, and it was confirmed that a better thermal runaway delay effect was obtained when the fireproof layer was formed on the upper and lower surfaces of the edge side of the heat insulation sheet, when it was formed on the entire side, or when it was formed on the upper and lower surfaces and the thickness of the fireproof layer formed on the upper surface was relatively thick. It was also confirmed that even if the fireproof layer was formed on the upper and lower surfaces of the side of the heat insulation sheet, an effective thermal runaway delay was possible when it was formed in a trapezoid shape so as to cover the upper surface of the side of the heat insulation sheet and a part of the side of the adjacent cell.

[0176] On the other hand, in Comparative Example 1, since no reinforcing material is included, it is difficult to delay thermal runaway when it occurs, and therefore, as can be seen from Table 2 above and the attached FIG. 8, a temperature rise in adjacent cells occurs immediately.

[0177] Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications can be made within the scope of the claims, the detailed description of the invention, and the accompanying drawings, and it is to be understood that these modifications also fall within the scope of the present invention. [Explanation of symbols]

[0178] 10 Cells 20. Heat Insulation Sheet 21 First base material 22 Second base material 23 Aerogel layer 30 Fireproof layer 100 Battery Module

Claims

1. A plurality of cells; A heat insulating sheet is provided between each of the plurality of cells, and the upper surface and the lower surface are arranged so as to face the adjacent cells, A fireproof layer formed on at least one of the edge sides between the upper surface and the lower surface of the heat insulating sheet, The battery module, wherein the fire-resistant layer comprises an inorganic binder.

2. The battery module according to claim 1 , wherein the cells are secondary battery cells.

3. The heat insulating sheet is A first substrate; A second substrate; The battery module according to claim 1 , comprising an aerogel layer disposed between the first substrate and the second substrate.

4. The battery module according to claim 3 , wherein each of the first substrate and the second substrate includes a resin, a metal, an inorganic material other than a metal, or a composite thereof.

5. 4. The battery module according to claim 3, wherein the aerogel layer comprises an aerogel, a fibrous support, and a functional material comprising a binder, a dispersant, or a combination thereof.

6. The aerogel has a BET specific surface area of ​​500 m ２ / g to 1,000m ２ The battery module according to claim 5 , wherein the tensile strength is 1 / g.

7. 6. The battery module according to claim 5, wherein the fibrous support is at least one selected from the group consisting of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers.

8. The binder comprises a water-based polymer binder, The battery module according to claim 5 , wherein the aqueous polymer binder is at least one selected from the group consisting of aqueous polymers, anionic water-soluble polymers, cationic water-soluble polymers, and water-dispersible polymers.

9. The battery module according to claim 5 , wherein the dispersant is at least one selected from the group consisting of a surfactant and a phosphate-based salt.

10. The battery module according to claim 5, wherein the aerogel layer comprises, with respect to a total amount of the aerogel, 10% by weight to 90% by weight of the aerogel, 5% by weight to 70% by weight of the fibrous support, and 0.5% by weight to 20% by weight of the functional material.

11. 2. The battery module according to claim 1, wherein the inorganic binder is at least one selected from the group consisting of aluminates, silicates, phosphates, sulfates, and chlorides.

12. 2. The battery module according to claim 1, wherein the inorganic binder is at least one selected from the group consisting of general calcium aluminate, pure calcium aluminate, sodium silicate, potassium silicate, lithium silicate, sodium phosphate, potassium phosphate, magnesium phosphate, zinc phosphate, calcium phosphate, aluminum phosphate, iron phosphate, sodium dihydrogen phosphate, sodium tripolyphosphate, sodium hexametaphosphate, magnesium sulfate, aluminum sulfate, iron (III) sulfate, magnesium chloride, iron (III) chloride, and polyaluminum chloride.

13. The battery module according to claim 1 , wherein the fire-resistant layer is formed on upper and lower surfaces or on the entire side surface of the insulation sheet.

14. 2. The battery module of claim 1, wherein the thickness of the fire-resistant layer formed on an upper surface of the side of the insulation sheet is 120% to 400% of the thickness of the fire-resistant layer formed on a lower surface.

15. the battery module includes an empty space other than the space in which the cells and the insulating sheet are disposed, the fireproof layer is formed to cover a side surface of the insulation sheet and a part or an entirety of side surfaces of adjacent two cells in an empty space formed on an upper portion of the battery module, The battery module according to claim 1 , wherein the fire-resistant layer is formed so that a thickness of a center portion is greater than a thickness of both edge portions.

16. disposing a plurality of cells; disposing an insulating sheet between the cells such that the upper and lower surfaces of the insulating sheet face adjacent cells; forming a fireproof layer on at least one of the edge sides between the upper surface and the lower surface of the heat insulating sheet; The method for manufacturing a battery module, wherein the fire-resistant layer comprises an inorganic binder.

17. The method for manufacturing a battery module according to claim 16 , wherein the step of forming the fire-resistant layer is performed before or after the insulating sheet is disposed between the plurality of cells.

18. 17. The method of claim 16, wherein the forming of the fire-resistant layer is performed by one or more of gap coating, dip coating, slot die coating, blade coating, dispensing, printing, brush coating, and porting using an inorganic binder solution dispersed in a solvent.

19. A battery pack comprising the battery module according to any one of claims 1 to 15.

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