Battery module, method of manufacturing battery module, and battery pack including battery module

Abstract

Examples of the present disclosure include a battery module comprising: a plurality of battery cells; an insulating sheet between the plurality of battery cells, the insulating sheet having an upper surface and a lower surface respectively disposed to face adjacent battery cells; and a refractory layer formed on at least one side surface portion of a boundary side surface between the upper surface and the lower surface of the insulating sheet, in which the refractory layer includes an inorganic binder. Examples of the present disclosure also include a method of manufacturing the battery module and a battery pack including the battery module.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0098057 filed on July 27, 2023 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] Example embodiments relate to a battery module, a method of manufacturing the battery module, and a battery pack including the battery module. Background Art

[0004] Secondary batteries are power storage systems configured to convert electrical energy into chemical energy, store chemical energy, and provide high energy density. Compared with primary batteries, which are usually non-rechargeable, secondary batteries are usually rechargeable and widely used in information technology (IT) devices (such as, for example, smart phones, mobile phones, laptops, and tablet computers). People are increasingly interested in electric vehicles to reduce or prevent environmental pollution, and high-capacity secondary batteries are usually used in electric vehicles. Secondary batteries usually exhibit characteristics such as, for example, high density, high output, and stability.

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

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

[0007] Example embodiments include a battery module, a method of manufacturing a battery module, and a battery pack including the battery module, the battery module having desired, advantageous, or improved thermal insulation, fire resistance, and flame retardancy or non-flammability to suppress the propagation of heat in a battery cell to battery cells adjacent thereto due to thermal runaway in the battery cell.

[0008] An example embodiment includes a battery module, the battery module comprising: a plurality of battery cells; an insulating sheet between the plurality of battery cells, the insulating sheet having an upper surface and a lower surface respectively arranged to face the battery cells adjacent thereto; and a fire-resistant layer formed on at least one side surface portion of a boundary side surface (hereinafter also referred to as a "side surface") between the upper surface and the lower surface of the insulating sheet, wherein the fire-resistant layer includes an inorganic binder.

[0009] Each or one or more of the plurality of battery cells may be or include a secondary battery cell.

[0010] The insulating sheet may include a first substrate, a second substrate, and an aerogel layer between the first substrate and the second substrate.

[0011] Each or one or more of the first substrate and the second substrate may include at least one of a resin, a metal, an inorganic material other than a metal, and a composite thereof.

[0012] The aerogel layer may include at least one of an aerogel, a fiber support, and a functional material, the functional material including at least one of a binder, a dispersant, and a combination thereof.

[0013] Aerogels can have a thermal conductivity of about 500 m 2 / g~1,000m 2 The Brunauer, Emmett and Teller (BET) specific surface area is in the range of 1.1747 W / g.

[0014] The fibrous support may include at least one of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers.

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

[0016] The dispersant may include at least one of a surfactant and a phosphate-based salt.

[0017] The aerogel may be included to account for about 10 wt % to about 90 wt %, the fibrous support may be included to account for about 5 wt % to about 70 wt %, and the functional material may be included to account for about 0.5 wt % to about 20 wt % based on the total amount of the aerogel layer.

[0018] The inorganic binder may include at least one of aluminates, silicates, phosphates, sulfates, and chlorides.

[0019] The inorganic binder may include at least one of calcium aluminate, calcium silicate, 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.

[0020] The fire-resistant layer may be formed on at least one of an upper side surface portion and a lower side surface portion of the side surface of the insulation sheet, or on substantially the entire side surface of the insulation sheet.

[0021] The thickness of the fire-resistant layer formed on the upper side surface portion of the side surface of the insulation sheet may be about 120% to about 400% of the thickness of the fire-resistant layer formed on the lower side surface portion of the side surface of the insulation sheet.

[0022] The battery module may include a void area other than the space in which the battery cells and the insulating sheet are located, and the refractory layer may be configured to wrap a portion or all of the side surface of the insulating sheet and the side surface of each battery cell adjacent thereto in the void area formed in the upper portion of the battery module, and the refractory layer may be formed so that the thickness of the central portion of the refractory layer is greater than the thickness of the opposite edges of the refractory layer.

[0023] Another example embodiment includes a method for manufacturing a battery module, the method comprising: arranging a plurality of battery cells; arranging an insulating sheet between the plurality of battery cells so that an upper surface and a lower surface of the insulating sheet respectively face the battery cells adjacent thereto; and forming a fire-resistant layer on at least one side surface portion of a boundary side surface between the upper surface and the lower surface of the insulating sheet, wherein the fire-resistant layer includes an inorganic binder.

[0024] The formation of the fire-resistant layer may be performed before or after the insulating sheet is disposed between the plurality of battery cells.

[0025] The formation of the refractory layer may be performed using a solution in which an inorganic binder is dispersed in a solvent by at least one of gap coating, dip coating, slot die coating, doctor blade coating, dispensing printing, brush coating, and embedding.

[0026] Another example embodiment includes a battery pack including a battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The attached drawings incorporated in this specification illustrate example embodiments and are used to further illustrate the technical concept of the present disclosure in conjunction with the detailed description of the following example embodiments, and the present disclosure is not to be construed as being limited to the contents shown in these drawings. In the drawings:

[0028] Figure 1 to Figure 5 is a schematic diagram showing the structure of a battery module according to an example embodiment;

[0029] Figure 6 is a schematic diagram showing a cross-sectional structure of an insulating sheet according to an example embodiment;

[0030] Figure 7 are photographs showing the results of the fire resistance evaluation experiment; and

[0031] Figure 8 is a graph showing the results of thermal runaway delay evaluation. DETAILED DESCRIPTION

[0032] Hereinafter, example embodiments will be described in detail so that those skilled in the art can easily implement the example embodiments. However, example embodiments may be implemented in many different forms and are not limited to the example embodiments described herein.

[0033] When the term "about" or "substantially" is used in conjunction with a numerical value in this specification, it is intended that the relevant numerical value includes a tolerance of ±10% around the stated numerical value. Moreover, when percentages are mentioned in this specification, it is intended that those percentages are based on concentration or weight, for example, concentration percentage or weight percentage. The expression "at most" includes an amount from zero to the expressed upper limit and all values ​​therebetween. When a range is specified, the range includes all values ​​therebetween, such as increments of 0.1%.

[0034] A battery module according to an example embodiment may include: a plurality of battery cells; an insulating sheet between the plurality of battery cells, the insulating sheet having an upper surface and a lower surface configured to respectively face the battery cells adjacent thereto; and a fire-resistant layer on at least one side surface portion of a boundary side surface between the upper surface and the lower surface of the insulating sheet, wherein the fire-resistant layer may include an inorganic binder.

[0035] In a battery module according to an example embodiment, a fire-resistant layer may be formed on at least one of an upper surface portion, a lower surface portion, a front surface portion, and a rear surface portion of a boundary side surface of an insulating sheet. As an example, the fire-resistant layer may be formed on an upper surface portion of a boundary side surface of an insulating sheet, on an upper surface portion and a lower surface portion of a boundary side surface of an insulating sheet, or on the entire boundary side surface of an insulating sheet. As another example, the fire-resistant layer may be substantially formed on an upper surface portion of a boundary side surface of an insulating sheet. Among them, the "upper surface portion" may mean a surface formed in an upward direction of a side surface portion based on the form in which the insulating sheet is set. That is, the upward direction of the "upper surface portion" is perpendicular to the upward direction of the "upper surface".

[0036] In the battery module according to example embodiments, the fire-resistant layer may be formed to cover a portion or the entire side surface of the insulation sheet (ie, an externally exposed portion of a surface of the insulation sheet that does not face the battery cells).

[0037] In the battery module according to example embodiments, the fire-resistant layer may be formed to further cover a portion or the entirety of a side surface of each battery cell adjacent to the insulating sheet.

[0038] The battery module having the above structure may have desired, advantageous or improved thermal insulation, fire resistance and flame retardancy or non-flammability, thereby suppressing the propagation of heat and flame in a battery cell to a battery cell adjacent thereto due to thermal runaway in the battery cell. Conventionally, when an insulating sheet is provided between battery cells for thermal insulation, the boundary side surface of the insulating sheet may be exposed to the air, and the propagation of heat or flame to the exposed side surface may occur during thermal runaway, which may be effectively suppressed by the battery module according to the example embodiment including the fire-resistant layer. The insulating sheet may have desired, advantageous or improved compressibility, mechanical strength and dimensional stability, and may reduce or prevent the aerogel layer from falling off due to external impact, thereby improving operability and reducing or preventing instrument contamination.

[0039] In example embodiments, the battery cell may be a secondary battery cell. The secondary battery cell may be, for example, a lithium secondary battery. The lithium secondary battery may be manufactured in various forms such as, for example, a lithium ion battery, an all-solid-state battery, or a lithium metal battery. For example, a lithium secondary battery may have a structure in which a positive electrode plate coated with a positive electrode active material and a negative electrode plate coated with a negative electrode active material are arranged with a separator interposed therebetween, and the positive electrode plate, the negative electrode plate, and the separator may be contained in a battery housing together with an electrolyte in a sealed state to constitute a secondary battery cell. Depending on the shape of the battery housing, the secondary battery cell may be classified into, for example, a cylindrical secondary battery cell, a prismatic secondary battery cell, or a pouch-shaped secondary battery cell, and a plurality of secondary battery cells may be connected in series or in parallel to each other to constitute a battery module.

[0040] Secondary battery cells may require a high degree of stability, so that, for example, when overcharged, decomposition and other side reactions may occur in the positive electrode active material or the electrolyte, whereby heat may be dissipated from the secondary battery cell, resulting in possible explosion of the secondary battery cell.

[0041] In a battery module according to an example embodiment, an insulating sheet may be disposed between a plurality of battery cells, and a fire-resistant layer may be provided on a side surface of the insulating sheet, whereby the battery module may have desired, advantageous or improved thermal insulation, fire resistance and flame retardancy or non-flammability, so that the propagation of heat and flame in a battery cell to a battery cell adjacent thereto due to thermal runaway in the battery cell may be reduced or suppressed.

[0042] In this description, the terms "left" and "right" are based on the drawings. For example, when the "left" surface of a rectangular parallelepiped is referred to as a first side surface, the "right" surface of the rectangular parallelepiped may be referred to as a second side surface opposite to the first side surface.

[0043] Figure 1To illustrate a schematic diagram of a portion of a battery module according to an example embodiment, the battery module includes an insulating sheet disposed between a plurality of battery cells, wherein a fire-resistant layer is formed on an upper side surface portion of a side surface of the insulating sheet. In this case, a flame generated in one battery cell can be blocked or prevented from moving to a gap region in the battery module through the upper side surface portion of the side surface of the insulating sheet, thereby effectively reducing or preventing the flame from propagating to a battery cell adjacent thereto.

[0044] See also Figure 1 , a battery module 100 according to an example embodiment may include a plurality of battery cells 10, and may include an insulating sheet 20 provided between the plurality of battery cells 10. The insulating sheet 20 may be disposed so that the upper surface and the lower surface of the insulating sheet 20 respectively face the battery cells 10 adjacent thereto. The battery module 100 may further include a fire-resistant layer 30 formed on an upper side surface portion of a side surface of the insulating sheet 20. Therefore, by preventing or blocking a flame in advance in the event of thermal runaway in one battery cell so as to advantageously reduce or inhibit the flame from propagating to other battery cells, a battery module with increased safety may be provided, and further a secondary battery pack including the battery module may be provided.

[0045] In example embodiments, the fire-resistant layer may be formed on an upper surface portion and a lower surface portion of a side surface of the insulating sheet, or on substantially the entire side surface of the insulating sheet. In this description, the terms "upper surface portion" and "lower surface portion" refer to surfaces formed on the upper side and the lower side of the insulating sheet, respectively, based on the form in which the insulating sheet is set.

[0046] As an example, the fire-resistant layer may be formed on substantially the entire side surface of the insulating sheet. In this case, the flame generated in one battery cell may be blocked or prevented from moving through the side surface of the insulating sheet to the gap area in the battery module, thereby effectively reducing or preventing the flame from spreading to the battery cells adjacent thereto.

[0047] As another example, the fire-resistant layer may be formed on the upper and lower side surface portions of the side surface of the insulating sheet, which are opposite to each other. In this case, the installation of the fire-resistant layer can be reduced or minimized, and the flame generated in one battery cell can be blocked or prevented from moving to the gap area in the battery module through the upper and lower side surface portions of the side surface of the insulating sheet, thereby more effectively reducing or preventing the flame from spreading to the battery cells adjacent thereto.

[0048] Figure 2 is a schematic diagram illustrating a portion of an example battery module including an insulation sheet disposed between a plurality of battery cells, wherein a fire-resistant layer is formed on an upper side surface portion and a lower side surface portion of a side surface of the insulation sheet.

[0049] See also Figure 2, the battery module 100 may include a plurality of battery cells 10, and may include an insulating sheet 20 between the plurality of battery cells 10. The insulating sheet 20 may be disposed so that the upper surface and the lower surface of the insulating sheet 20 respectively face the battery cells 10 adjacent thereto. The battery module 100 may further include a fire-resistant layer 30 formed on the upper surface portion and the lower surface portion of the side surface of the insulating sheet 20. Therefore, by preventing or blocking the flame in advance in the event of thermal runaway in one battery cell to advantageously suppress the flame from propagating to other battery cells, a battery module with increased safety may be provided, and further a secondary battery pack including the battery module may be provided.

[0050] In the example embodiment, even if the fire-resistant layer is formed on the entire or substantially the entire side surface of the insulating sheet, the fire-resistant layer formed on the front side surface portion and the rear side surface portion of the side surface of the insulating sheet is not shown in the cross-sectional view, so the fire-resistant layer formed on the front side surface portion and the rear side surface portion of the side surface of the insulating sheet is not shown in the cross-sectional view. Figure 2 Shown in.

[0051] In an example embodiment, the thickness of the fire-resistant layer formed on the upper side surface portion of the side surface of the insulating sheet may be about 120% to about 400%, about 150% to about 350%, or about 200% to about 350% of the thickness of the fire-resistant layer formed on the lower side surface portion of the side surface of the insulating sheet. The thickness of the fire-resistant layer formed on the upper side surface portion of the side surface of the insulating sheet may be at least one of about 1.2 to about 4 times, about 1.5 to about 3.5 times, and about 2 to about 3.5 times the thickness of the fire-resistant layer formed on the lower side surface portion of the side surface of the insulating sheet. As described above, by controlling the thickness ratio of the fire-resistant layer formed on the upper side surface portion and the lower side surface portion of the side surface of the insulating sheet, in the case of thermal runaway in one battery cell, it is possible to effectively block or prevent the flame from moving upward and spreading.

[0052] Figure 3 A schematic diagram showing a portion of a battery module including an insulating sheet between a plurality of battery cells, wherein a fire-resistant layer is formed on an upper surface portion and a lower surface portion of a side surface of the insulating sheet, and the thickness of the fire-resistant layer formed on the upper surface portion is greater than the thickness of the fire-resistant layer formed on the lower surface portion.

[0053] See also Figure 3, the battery module 100 may include a plurality of battery cells 10, and may include an insulating sheet 20 between the plurality of battery cells 10. The insulating sheet 20 may be arranged so that the upper surface and the lower surface of the insulating sheet respectively face the battery cells 10 adjacent thereto. The battery module 100 may further include a fire-resistant layer 30 formed on the upper surface portion and the lower surface portion of the side surface of the insulating sheet 20, wherein the thickness of the fire-resistant layer formed on the upper surface portion may be greater than the thickness of the fire-resistant layer formed on the lower surface portion. Therefore, by preventing or blocking the upward movement of the flame in advance in the event of thermal runaway in one battery cell to advantageously reduce or inhibit the spread of the flame to other battery cells, a battery module with increased safety can be provided, and a secondary battery pack including the battery module is further provided.

[0054] In an example embodiment, the battery module may include a void area other than the space in which the battery cell and the insulating sheet are disposed, the refractory layer may be formed to wrap a part or all of the side surface of the insulating sheet and the side surface of each battery cell adjacent thereto in the void area formed in the upper portion of the battery module, and the refractory layer may be formed so that the thickness of the central portion of the refractory layer is greater than the thickness of the opposite edge of the refractory layer. For example, the refractory layer may be formed in a trapezoidal shape, a dome shape, etc. As described above, when the refractory layer is formed so that the thickness of the central portion of the refractory layer is greater than the thickness of the opposite edge of the refractory layer, by shielding the heat and flame of the central portion of the refractory layer, during thermal runaway in the battery cell, the flame and heat in one battery cell can be blocked or prevented from being transferred to the battery cell adjacent thereto through the vent located in the center in the direction of the side surface of the battery cell, so further thermal runaway can be delayed or prevented.

[0055] Figure 4 is a schematic diagram showing a portion of a battery module including an insulation sheet between a plurality of battery cells, wherein a fire-resistant layer is formed on an upper side surface portion of a side surface of the insulation sheet, and the fire-resistant layer is formed in a trapezoidal shape.

[0056] See also Figure 4, the battery module 100 may include a plurality of battery cells 10, and may include an insulating sheet 20 between the plurality of battery cells 10. The insulating sheet 20 may be arranged so that the upper surface and the lower surface of the insulating sheet face the battery cells 10 adjacent thereto, respectively. The battery module 100 may further include a fire-resistant layer 30 formed on the upper side surface portion of the side surface of the insulating sheet 20. The fire-resistant layer 30 may be formed in a trapezoidal shape, wherein the thickness of the central portion of the fire-resistant layer 30 may be greater than the thickness of the opposite edge of the fire-resistant layer 30. The fire-resistant layer 30 may also be formed on the lower side surface portion of the side surface of the insulating sheet, wherein the thickness of the fire-resistant layer 30 formed on the lower side surface portion may be less than the thickness of the fire-resistant layer 30 formed on the upper side surface portion. Therefore, by preventing or blocking the flame in advance in the case of thermal runaway in one battery cell to substantially suppress the flame from propagating to other battery cells, a battery module with increased safety can be provided, and a secondary battery pack including the battery module is further provided.

[0057] Figure 5 is a schematic diagram showing a portion of a battery module including an insulating sheet between a plurality of battery cells, wherein a fire-resistant layer is formed on an upper side surface portion of a side surface of the insulating sheet, and the fire-resistant layer is formed in a dome shape.

[0058] See also Figure 5 , the battery module 100 may include a plurality of battery cells 10, and may include an insulating sheet 20 between the plurality of battery cells 10. The insulating sheet 20 may be disposed so that the upper and lower surfaces of the insulating sheet 20 face the battery cells 10 adjacent thereto, respectively. The battery module 100 may further include a fire-resistant layer 30 formed on an upper side surface portion of a side surface of the insulating sheet 20, wherein the fire-resistant layer 30 may have a dome shape, wherein the thickness of the central portion of the fire-resistant layer 30 is greater than the thickness of the opposite edge of the fire-resistant layer 30. The fire-resistant layer 30 may also be formed on a lower side surface portion of a side surface of the insulating sheet 20, wherein the thickness of the fire-resistant layer 30 formed on the lower side surface portion may be lower than the thickness of the fire-resistant layer 30 formed on the upper side surface portion. Therefore, by preventing or blocking the flame in advance in the event of thermal runaway in one battery cell to substantially suppress the flame from propagating to other battery cells, a battery module with increased safety can be provided, and a secondary battery pack including the battery module is further provided.

[0059] In example embodiments, the insulating sheet may include a first substrate, a second substrate, and an aerogel layer between the first substrate and the second substrate. The first substrate and the second substrate may form an upper surface and a lower surface of the insulating sheet, respectively, and may be configured to face battery cells adjacent thereto, respectively. The insulating sheet may include a boundary side surface provided between the upper surface and the lower surface of the insulating sheet.

[0060] Figure 6is a schematic diagram illustrating a structure of an insulation sheet according to an example embodiment.

[0061] See also Figure 6 The insulating sheet 20 may have a structure including a first substrate 21, a second substrate 22, and an aerogel layer 23 between the first substrate 21 and the second substrate 22. The first substrate 21 and the second substrate 22 may form the upper and lower surfaces of the insulating sheet 20, respectively, and may be configured to face the battery cells 10 adjacent thereto, respectively.

[0062] Each or at least one of the first substrate and the second substrate may be made of at least one of resin, metal and inorganic materials other than metal, or include but are not limited to at least one of resin, metal and inorganic materials other than metal, or may be made of or include a composite thereof. The form of the substrate may be, but is not limited to, a film, a membrane, a sheet, etc.

[0063] The resin may be, for example, at least one of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyamide.

[0064] The metal may be or include, for example, at least one of copper, nickel, cobalt, iron, chromium, vanadium, palladium, ruthenium, rhodium, molybdenum, tungsten, iridium, silver, gold, and platinum. When a substrate made of or including any of the above metals is used, the substrate may be subjected to an anti-corrosion treatment or an insulation treatment as required.

[0065] The inorganic material other than the metal may be or include at least one of calcium carbonate (CaCO 3 ), talc, and mica.

[0066] As an example, each or at least one of the first substrate and the second substrate may include an inorganic material other than metal, and as a specific example, the substrate may include mica. In this case, thermal insulation, durability, etc. of the insulating sheet may be improved.

[0067] The aerogel layer may include an aerogel, a fiber support, and a functional material, wherein the functional material includes a binder, a dispersant, or a combination thereof.

[0068] In an example embodiment, the aerogel may have a diameter of about 500 m 2 / g~about 1,000m 2 / g BET specific surface area. For example, the aerogel may have a BET specific surface area of ​​about 500 m 2 / g~about 950m 2 / g, about 550m 2 / g~about 950m 2 / g or about 600m 2 / g~about 900m 2When the aerogel having a BET specific surface area value within the above range is included, an insulating sheet that can effectively reduce or prevent heat transfer and heat propagation between a plurality of battery cells can be provided.

[0069] The average particle size D50 of the aerogel may be about 5 to about 200 μm, about 10 to about 100 μm, or about 20 to about 50 μm. When the aerogel having a particle size within the above range is included, thermal insulation may be improved, thereby delaying heat transfer between a plurality of battery cells.

[0070] The average particle size D50 can be measured, for example, using a laser diffraction method or a scanning electron microscope (SEM), where the average particle size D50 of the particles can be defined as the particle size at 50% of the particle size distribution (the particle size corresponding to the cumulative 50% volume of the particle size distribution).

[0071] The content of the aerogel may be about 10 wt % to about 90 wt %, about 30 wt % to about 70 wt %, or about 40 wt % to about 60 wt % based on the total amount of the aerogel layer. When an insulating sheet including aerogel within the above range is manufactured, thermal insulation of the insulating sheet may be improved.

[0072] In example embodiments, the fiber support may be included in the aerogel layer, and thus the durability of the insulation sheet formed using the aerogel layer may be improved.

[0073] The fibrous support may include fibers used as a support made of, for example, a common insulating material or including, for example, a common insulating material. For example, the fibrous support may be or include at least one of natural fibers, silica fibers, glass fibers, ceramic fibers, carbon fibers, graphite fibers, mineral fibers, and polymer fibers. As an example, the fibrous support may include, but is not limited to, glass fibers. As an example, glass fibers may include, but are not limited to, glass wool.

[0074] The natural fiber may be, for example, at least one of hemp, jute, flax, coir, kenaf, and cellulose.

[0075] The ceramic fiber may be at least one of silicon carbide, silicon nitride, boron nitride and aluminum silicon carbide.

[0076] The mineral fiber may include, for example, at least one of basalt, diatomaceous earth, alumina, boron, quartz, silica, slag, and rock.

[0077] The polymer fiber may be, for example, at least one of nylon, polyimide, polyamide, polybenzimidazole, polybenzoxazole, polyamideimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyethylene (PE) and polypropylene (PP). As an example, the polymer fiber may be, but is not limited to, at least one of polyimide, polyamide and polybenzimidazole.

[0078] The fibrous support may be in the form of, for example, but not limited to, at least one of powder, wool, chops, felt, batting, and lofted batting.

[0079] The average diameter of the fiber support can be, for example, about 0.1 μm to about 20 μm, about 0.1 μm to about 15 μm, about 0.1 μm to about 5 μm, about 1 μm to about 15 μm, or about 3 μm to about 10 μm. By including a fiber support having an average diameter within the above range, the structure of the aerogel layer can be hardened and the manufacturing cost can be reduced.

[0080] The average length of the fibrous support may be, for example, about 50 μm to about 1000 μm, about 70 μm to about 800 μm, or about 100 μm to about 600 μm. By including the fibrous support having an average length within the above range, the aerogel layer may be robustly formed and durability may be improved.

[0081] The fiber support may be contained in an amount of about 5 wt % to about 70 wt %, about 25 wt % to about 60 wt %, or about 30 wt % to about 50 wt % based on the total amount of the aerogel layer. When an aerogel layer including the fiber support within the above range is used to manufacture an insulating sheet, durability may be improved.

[0082] In example embodiments, the binder may include an aqueous polymer binder. For example, the aqueous polymer binder may be at least one of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

[0083] The water-based polymer may be, but is not limited to, at least one of, for example, polyvinyl alcohol, polyethylene oxide, polyacrylamide, and polyvinyl pyrrolidone.

[0084] The anionic water-soluble polymer may be a polymer having at least one functional group of carboxylic acid, sulfonic acid, sulfate, phosphate, and salts thereof. For example, the anionic water-soluble polymer may be a polymer having a carboxylic acid group, and may include, but is not limited to, polymaleic acid as an example.

[0085] The cationic water-soluble polymer may be a polymer having at least one functional group of amine, ammonium, phosphonium, sulfonium and salts thereof. For example, the cationic water-soluble polymer may be a polymer having an amine group, and may be, but is not limited to, at least one of polyvinylamine and polyamine as a specific example.

[0086] The water-dispersible polymer may be, but is not limited to, at least one of a water-dispersible polyurethane and a water-dispersible polyester.

[0087] The binder may include a water-based polymer and a water-dispersible polymer. For example, the binder may include a water-based polymer having a bonding property and a dispersible property and a water-dispersible polymer having fire resistance. As an example, the binder may include polyvinyl alcohol and a water-dispersible polyurethane.

[0088] The weight ratio of the water-based polymer to the water-dispersible polymer may be about 1: 1 to about 1: 5, about 1: 1 to about 1: 4, or about 1: 2 to about 1: 3. When the weight ratio of the water-based polymer to the water-dispersible polymer is within the above range, in addition to the thermal insulation, dustiness, and compressibility of the insulation sheet, the fire resistance and mechanical properties of the insulation sheet may be further improved.

[0089] The binder may be present in an amount of about 0.5 wt % to about 20 wt %, about 2 wt % to about 15 wt %, or about 8 wt % to about 15 wt % based on the total amount of the aerogel layer. When an insulating sheet is manufactured using the aerogel composition including the binder within the above range, the dust formation of the insulating sheet may be improved.

[0090] In example embodiments, the dispersant may be at least one of a surfactant and a phosphate salt. For example, the dispersant may include, but is not limited to, at least one of a nonionic surfactant, an anionic surfactant, an amphoteric surfactant, a natural surfactant (such as lecithin), and a phosphate ester.

[0091] When the dispersant is further included, the fibrous support and the aerogel may be present in the aerogel layer in a more uniformly dispersed state.

[0092] The content of the dispersant may be about 0.1 wt % to about 6 wt %, about 0.1 wt % to about 5 wt %, or about 0.1 wt % to about 3 wt % based on the total amount of the aerogel layer. When the dispersant is included within any of the above ranges, an insulation sheet having desired, advantageous, or improved thermal insulation, compressibility, and dust formation can be manufactured.

[0093] The binder and the dispersant may be included in a weight ratio of about 1:0.001 to about 1:0.67, about 1:0.001 to about 1:0.5, or about 1:0.001 to about 1:0.3. Mixing the binder and the dispersant in a weight ratio within the above range may result in a more uniform dispersion of the aerogel in the aerogel layer.

[0094] In example embodiments, the fibrous support may be included at about 5 wt % to about 70 wt %, the aerogel may be included at about 10 wt % to about 90 wt %, and the functional material may be included at about 0.5 wt % to about 20 wt % based on the total amount of the aerogel layer.

[0095] As an example, the fibrous support may be included at about 25 wt % to about 60 wt %, the aerogel may be included at about 30 wt % to about 70 wt %, and the binder may be included at about 2 wt % to about 15 wt % based on the total amount of the aerogel layer.

[0096] Based on the total amount of the aerogel layer, the fiber support may be included to account for about 30 wt% to about 50 wt%, the aerogel may be included to account for about 40 wt% to about 60 wt%, and the binder may be included to account for about 8 wt% to about 15 wt%. When the aerogel layer is formed within the above range, it is possible to achieve desired, advantageous or improved thermal insulation while improving durability, and it is possible to improve the bonding between the fiber support and the aerogel, thereby reducing or preventing dust generation.

[0097] As another example, based on the total amount of the aerogel layer, a fibrous support may be included to account for about 25 wt % to about 60 wt %, an aerogel may be included to account for about 30 wt % to about 70 wt %, a binder may be included to account for about 2 wt % to about 15 wt %, and a dispersant may be included to account for about 0.1 wt % to about 5 wt %.

[0098] Based on the total amount of the aerogel layer, the fiber support may be included to account for about 30 wt% to about 50 wt%, the aerogel may be included to account for about 40 wt% to about 60 wt%, the binder may be included to account for about 5 wt% to about 10 wt%, and the dispersant may be included to account for about 0.1 wt% to about 3 wt%. When the aerogel layer is formed within any of the above ranges, the dispersibility of the aerogel can be improved, the desired, advantageous or improved thermal insulation can be achieved, the durability can be improved, and the bonding between the fiber support and the aerogel can be improved, thereby reducing or preventing dust generation.

[0099] In the aerogel layer, the surface of the fiber support may be coated with aerogel. In this case, the aerogel and the fiber support may be substantially evenly distributed, and the bonding between the aerogel and the fiber support may be high, thereby being able to reduce dust generated by the shedding of the aerogel.

[0100] In example embodiments, the aerogel layer may have a single layer structure or a multi-layer structure. When the aerogel layer has a multi-layer structure, the aerogel layer may have about 2 to about 10 layers, about 2 to about 7 layers, or about 2 to about 5 layers.

[0101] In example embodiments, the fire-resistant layer may include or may consist of an inorganic binder.

[0102] The inorganic binder may be at least one of aluminates, silicates, phosphates, sulfates and chlorides.

[0103] The aluminate may be calcium aluminate.

[0104] The silicate may be at least one of calcium silicate, sodium silicate, potassium silicate and lithium silicate.

[0105] The phosphate may be at least one of sodium phosphate, potassium phosphate, magnesium phosphate, zinc phosphate, calcium phosphate, aluminum phosphate, iron phosphate, sodium dihydrogen phosphate, sodium tripolyphosphate, and sodium hexametaphosphate.

[0106] The sulfate may be at least one of magnesium sulfate, aluminum sulfate, and iron (III) sulfate.

[0107] The chloride may be at least one of magnesium chloride, iron (III) chloride and polyaluminium chloride.

[0108] As an example, the inorganic binder may be at least one of calcium aluminate, calcium silicate, sodium silicate, and aluminum phosphate. By including the inorganic binder, fire resistance of the insulation sheet may be improved, and flame propagation between battery cells may be reduced or prevented.

[0109] A method for manufacturing a battery module according to an example embodiment may include: arranging a plurality of battery cells; arranging an insulating sheet between the plurality of battery cells so that an upper surface and a lower surface of the insulating sheet respectively face the battery cells adjacent thereto; and forming a fire-resistant layer on at least one side surface portion of a boundary side surface between the upper surface and the lower surface of the insulating sheet.

[0110] In example embodiments, in providing a plurality of battery cells, a form in which the plurality of battery cells are provided is not particularly limited, and the plurality of battery cells may be appropriately provided according to the type of battery.

[0111] In example embodiments, the insulating sheet may be disposed between the plurality of battery cells. The insulating sheet may be disposed such that an upper surface and a lower surface of the insulating sheet face the battery cells adjacent thereto, respectively.

[0112] The insulating sheet may be manufactured by forming a first substrate, applying the aerogel composition to the first substrate, and forming a second substrate on the applied aerogel composition.

[0113] The detailed description of each of the first substrate and the second substrate may be the same as described above, and the size and shape of each substrate may be appropriately adjusted according to the structure of the battery cell.

[0114] The aerogel composition may be produced by mixing a solvent with a functional material including a binder, a dispersant, or a combination thereof to produce a solvent mixture, mixing the solvent mixture with an aerogel to produce an aerogel mixture, and mixing the aerogel mixture with a fibrous support to produce the aerogel composition.

[0115] When the solvent is mixed with the functional material to produce a solvent mixture, the solvent may be mixed with the binder, or the solvent may be mixed with the binder and the dispersant.

[0116] The solvent may be at least one of a polar solvent and a non-polar solvent.

[0117] The polar solvent may include water, an alcohol solvent, or a combination thereof.

[0118] The water may include purified water, deionized water, or a combination thereof.

[0119] The alcohol solvent may be, but is not limited to, at least one of methanol, ethanol, propanol, pentanol, butanol, hexanol, ethylene glycol, propylene glycol, diethylene glycol and glycerol.

[0120] The non-polar solvent may include a hydrocarbon solvent. For example, the hydrocarbon solvent may be at least one of hexane, pentane, heptane, toluene and benzene, and may be, but is not limited to, an alkane solvent (such as hexane) or a mixture including an alkane solvent.

[0121] The solvent may include water. Using water as a solvent can effectively reduce raw material costs and post-processing costs. However, when water is used as a solvent, water may not be fully mixed with the hydrophobic aerogel. In an example embodiment, the aerogel can be uniformly dispersed by controlling the design of the mixing process, the mixing conditions, the addition of a binder and a dispersant, and the amount of the binder and the dispersant. Such a substantially uniform dispersion of the aerogel in the composition can form an insulating sheet of low thickness with desired or improved thermal insulation, durability, and dust formation without using a large amount of a binder.

[0122] The solvent may be included such that the weight ratio of the solvent to the total amount of solids in the aerogel composition is about 1:1 to about 1:90. For example, the weight ratio of the solvent to the total amount of solids in the aerogel composition may be about 1:50 to about 1:70, 1:20 to about 1:30, or 1:2 to about 1:10. By controlling the weight ratio of the solvent to the total amount of solids in the aerogel composition within the above range, the viscosity may be controlled to coat the aerogel layer.

[0123] The detailed description of the binder and dispersant may be similar or the same as described above.

[0124] In mixing the solvent mixture with the aerogel to produce the aerogel mixture, the detailed description of the aerogel may be similar or the same as described above.

[0125] In mixing the aerogel mixture with the fibrous support to produce the aerogel composition, the detailed description of the fibrous support may be similar or identical to the above description.

[0126] In example embodiments, the aerogel composition may further include a silane compound. The silane compound may be, for example, at least one of 3-(trimethoxysilyl)propyl methacrylate, methyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, octadecyltrimethoxysilane, ethyltriethoxysilane, and 3-glycidoxypropyltrimethoxysilane. Further inclusion of a silane compound may further improve dispersibility.

[0127] In example embodiments, the aerogel composition may further include additives such as a wetting agent, an emulsifier, a compatibilizer, a viscosity modifier, a pH modifier, a stabilizer, an antioxidant, an acid or base scavenger, a metal inhibitor, a defoaming agent, an antistatic agent, a tackifier, an adhesion promoter, a coupling agent, a flame retardant, an impact modifier, a pigment, a dye, a colorant, or a deodorant.

[0128] In each of mixing a solvent with a functional material including a binder, a dispersant or a combination thereof to produce a solvent mixture, mixing the solvent mixture with an aerogel powder to produce an aerogel composition, and mixing the aerogel mixture with a fiber support to produce an aerogel composition, a mixer may be used for mixing. For example, the mixer may include, but is not limited to, a planetary mixer and a Thinky mixer. TM mixer.

[0129] As an example, a planetary mixer can be used to mix the solvent mixture with the aerogel powder. Using a planetary mixer to mix the solvent mixture with the aerogel powder can result in the aerogel powder being substantially uniformly dispersed in the solvent.

[0130] A planetary mixer may be a device that can be used to mix or stir different substances in order to produce a homogenous mixture. A planetary mixer may include blades that are capable of planetary motion.

[0131] In example embodiments, the planetary mixer may include at least one of one or more planetary blades and one or more high-speed dispersing blades. As an example, the planetary mixer may include at least one planetary blade and at least one high-speed dispersing blade.

[0132] Each or at least one of the planetary blades and the high-speed dispersion blades can be continuously rotated about its axis. The rotation speed can be expressed in revolutions per minute (rpm).

[0133] In an example embodiment, the planetary mixer may include a first blade and a second blade having different rotation axes. For example, the first blade may be a low speed blade and the second blade may be a high speed blade. Low speed and high speed refer to the relative rotation speed between the first blade and the second blade. As an example, the first blade may be an open blade and the second blade may be a Despa TM blade.

[0134] The rotation speed of the first blade may be, for example, about 10 rpm to about 100 rpm, about 10 rpm to about 60 rpm, or about 30 rpm to about 70 rpm. The rotation speed of the second blade may be, for example, about 100 rpm to about 2000 rpm, about 100 rpm to about 1000 rpm, about 300 rpm to about 1700 rpm, or about 500 rpm to about 1700 rpm.

[0135] When the functional material is added to the solvent and mixed with the solvent, the rotation speed of the first blade may be about 10 rpm to about 60 rpm, about 20 rpm to about 50 rpm, or about 30 rpm to about 40 rpm, and the rotation speed of the second blade may be about 300 rpm to about 1700 rpm, about 600 rpm to about 1000 rpm, or about 700 rpm to about 800 rpm. As described above, when the solvent and the functional material are mixed with each other, a solvent mixture in which a binder, a dispersant, or a combination thereof is substantially uniformly dispersed can be produced to facilitate mixing of aerogels in subsequent processes.

[0136] When the solvent mixture and the aerogel powder are mixed with each other, the rotation speed of the first blade of the mixer may be about 30 rpm to about 70 rpm, about 40 rpm to about 70 rpm, or about 60 rpm to about 70 rpm, and the rotation speed of the second blade may be about 500 rpm to about 1700 rpm, about 600 rpm to about 1600 rpm, or about 800 rpm to about 1500 rpm. As described above, when the aerogel powder is added to the solvent mixture and mixed with the solvent mixture, the aerogel powder can be prevented or blocked from agglomerating to induce uniform dispersion.

[0137] When the aerogel mixture and the fiber support are mixed with each other, the rotation speed of the first blade of the mixer may be about 10 rpm to about 60 rpm, about 20 rpm to about 50 rpm, or about 30 rpm to about 40 rpm, and the rotation speed of the second blade may be about 300 rpm to about 1700 rpm, about 400 rpm to about 1500 rpm, or about 800 rpm to about 1200 rpm. Mixing the aerogel mixture with the fiber support as described above can remove air bubbles in the composition, control viscosity, and facilitate the dispersion of the fiber support in the substantially uniformly dispersed aerogel, so that the aerogel surrounds the fiber support in the composition. A binder may be present between the aerogel and the fiber support to improve the bonding between the aerogel and the fiber support.

[0138] By forming an aerogel layer using the method according to example embodiments, thermal insulation and durability may be improved, and aerogel may be prevented from falling off and generating dust when an insulation sheet is manufactured or when the insulation sheet is installed in a device, or when external vibration occurs.

[0139] In example embodiments, forming the fire-resistant layer on at least one side surface portion of a boundary side surface between an upper surface and a lower surface of the insulation sheet may be performed before or after disposing the insulation sheet between the plurality of battery cells.

[0140] As an example, the formation of the fire-resistant layer may be performed before the insulating sheet between the plurality of battery cells is disposed. In this case, after the insulating sheet is manufactured, the fire-resistant layer may be formed on at least one side surface portion of the side surface of the insulating sheet, and the insulating sheet having the fire-resistant layer formed thereon may be disposed between the plurality of battery cells.

[0141] The fire-resistant layer can be formed by a solution process such as gap coating, dip coating, slot die coating, doctor blading, dispensing printing, brush coating, or insert casting using molding. The fire-resistant layer can be formed by applying an inorganic binder in a solution state dispersed in a solvent or the like to at least one side surface portion of the side surface of the insulating sheet and drying it at room temperature or at a temperature of about 40° C. to about 80° C. for less than 24 hours.

[0142] As another example, the fire-resistant layer may be formed after the insulating sheet between the plurality of battery cells is disposed. In this case, the insulating sheet may be disposed between the plurality of battery cells, and the fire-resistant layer may be formed on at least one side surface portion of the side surface of the insulating sheet.

[0143] The fire-resistant layer can be formed by a solution process such as gap coating, dispensing printing, brushing or embedding. The fire-resistant layer can be formed by injecting an inorganic binder in a solution state dispersed in a solvent or the like into a battery module (in which a plurality of battery cells and an insulating sheet are arranged) to apply it to at least one side surface portion of the side surface of the insulating sheet exposed in the battery module, and drying it at room temperature or at a temperature of about 40° C. to about 80° C. for less than 24 hours.

[0144] Example embodiments may include a battery pack including a battery module. A plurality of battery modules may be provided in the battery pack.

[0145] Hereinafter, examples will be described. However, the following examples are intended only to illustrate or describe the present disclosure and should not be construed as limiting the present disclosure. Those skilled in the art can fully infer the details not described herein from a technical point of view, so their description will be omitted.

[0146] (Battery module manufacturing)

[0147] Example 1

[0148] 1. Manufacturing of insulation sheets

[0149] The mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich) as a binder to deionized water as a solvent and stirring at 30 rpm using an open blade and Despa TM The blades were mixed at 700 rpm to produce a solvent mixture. Subsequently, the BET value was set at 800 m 2 / g of aerogel powder was added to the solvent mixture and stirred at 70 rpm using an open blade and Despa TM The aerogel mixture was made by adding glass wool to the aerogel mixture and mixing with an open blade at 30 rpm and using Despa TM The blades were mixed at 1200 rpm to produce an aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0150] The solid contents of the manufactured aerogel composition were measured to be 50 wt % of aerogel, 40 wt % of glass wool and 10 wt % of polyvinyl alcohol.

[0151] The aerogel composition slurry was coated onto a 0.1 mm thick mica sheet (Pamica TM , Muscovite TM), another 0.1 mm thick mica sheet was laminated thereon in a sandwich manner, and coated using a rolling method. Subsequently, an aerogel layer was formed by drying at 60° C. for 24 hours to manufacture an insulating sheet. The total thickness of the manufactured insulating sheet was measured to be 1.38 mm.

[0152] 2. Manufacturing of refractory layer

[0153] The fire-resistant layer was formed by applying calcium silicate as an inorganic binder to the upper side surface portion of the side surface of the insulating sheet using a dispensing printing method. The thickness of the fire-resistant layer was measured to be 0.3 mm.

[0154] 3. Manufacturing of battery modules

[0155] A plurality of battery cells are disposed in a battery module, and an insulating sheet having a fire-resistant layer formed thereon is disposed between the plurality of battery cells.

[0156] Example 2

[0157] A battery module was manufactured using substantially the same method as in Example 1, except that calcium aluminate was used as the inorganic binder instead of calcium silicate.

[0158] Example 3

[0159] A battery module was manufactured using substantially the same method as in Example 1, except that aluminum phosphate was used instead of calcium silicate as the inorganic binder.

[0160] Example 4

[0161] A battery module was manufactured using substantially the same method as in Example 1, except that a brush coating method was used instead of a dispensing printing method to manufacture the fire-resistant layer.

[0162] Example 5

[0163] The battery module was manufactured using substantially the same method as in Example 1, except that the fire-resistant layer was formed on the upper and lower surface portions of the side surface of the insulating sheet. The thickness of the fire-resistant layer formed at the upper and lower surface portions of the side surface of the insulating sheet was measured to be 0.3 mm, respectively.

[0164] Example 6

[0165] The battery module was manufactured using substantially the same method as in Example 1, except that the fire-resistant layer was formed on the entire side surface of the insulating sheet. The thickness of the fire-resistant layer formed on the upper side surface portion, the lower side surface portion, the front side surface portion, and the rear side surface portion of the side surface of the insulating sheet was measured to be 0.3 mm respectively.

[0166] Example 7

[0167] A battery module is manufactured using substantially the same method as in Example 1, except that a fire-resistant layer is formed on the upper surface portion and the lower surface portion of the side surface of the insulating sheet so that the thickness of the fire-resistant layer formed on the upper surface portion is 0.7 mm and the thickness of the fire-resistant layer formed on the lower surface portion is 0.3 mm.

[0168] Example 8

[0169] 1. Manufacturing of insulation sheets

[0170] The mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich) as a binder to deionized water as a solvent and stirring at 30 rpm using an open blade and Despa TM The blades were mixed at 700 rpm to produce a solvent mixture. Subsequently, the BET value was set at 800 m 2 / g of aerogel powder was added to the solvent mixture and stirred at 70 rpm using an open blade and Despa TM The aerogel mixture was made by adding glass wool to the aerogel mixture and using an open blade at 30 rpm and using Despa TM The blades were mixed at 1200 rpm to produce an aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0171] The solid contents of the manufactured aerogel composition were measured to be 50 wt % of aerogel, 40 wt % of glass wool and 10 wt % of polyvinyl alcohol.

[0172] The aerogel composition slurry was coated onto a 0.1 mm thick mica sheet (Pamica TM , Muscovite TM ), another 0.1 mm thick mica sheet was laminated thereon in a sandwich manner, and coated using a rolling method. Subsequently, an aerogel layer was formed by drying at 60° C. for 24 hours to manufacture an insulating sheet. The total thickness of the manufactured insulating sheet was measured to be 1.38 mm.

[0173] 2. Manufacturing of battery modules

[0174] A plurality of battery cells are disposed in the battery module, and an insulating sheet is disposed between the plurality of battery cells.

[0175] 3. Manufacturing of refractory layer

[0176] Calcium silicate as an inorganic binder was injected into a mold (having a trapezoidal void area defined therein) in a solution state to wrap the upper and lower side surface portions of the side surface of the insulating sheet disposed between a plurality of battery cells and a portion of the side surface of the battery cell adjacent thereto, and dried to form a trapezoidal shaped fireproof layer. The thickness of the central portion of the fireproof layer was measured to be 0.7 mm, and the thickness of the opposite edges of the fireproof layer was measured to be 0.5 mm.

[0177] Comparative Example 1

[0178] 1. Manufacture of aerogel compositions

[0179] The mixture was prepared by adding polyvinyl alcohol (Sigma Aldrich) as a binder to deionized water as a solvent and stirring at 30 rpm using an open blade and Despa TM The blades were mixed at 700 rpm to produce a solvent mixture. Subsequently, the BET value was set at 800 m 2 / g of aerogel powder was added to the solvent mixture and stirred at 70 rpm using an open blade and Despa TM The aerogel mixture was made by adding glass wool to the aerogel mixture and using an open blade at 30 rpm and using Despa TM The blades were mixed at 1200 rpm to produce an aerogel composition. A planetary mixer (DNTEK, PT-005) was used for mixing.

[0180] The solid contents of the manufactured aerogel composition were measured to be 50 wt % of aerogel, 40 wt % of glass wool and 10 wt % of polyvinyl alcohol.

[0181] 2. Manufacturing of insulation sheets

[0182] The aerogel composition slurry was coated onto a 0.1 mm thick mica sheet (Pamica TM , Muscovite TM ), another 0.1 mm thick mica sheet was laminated thereon in a sandwich manner, and coated using a rolling method. Subsequently, an aerogel layer was formed by drying at 60° C. for 24 hours to manufacture an insulating sheet. The total thickness of the manufactured insulating sheet was measured to be 1.38 mm.

[0183] (Experimental example)

[0184] Experimental Example 1: Evaluation of fire resistance

[0185] The fire resistance of each of the insulating sheets manufactured in Examples 1 to 8 and Comparative Example 1 was evaluated.

[0186] A gas ignition torch device was used to emit a flame toward the insulating sheet in the direction of the side surface of the insulating sheet having a fire-resistant layer at an emission temperature of 1100±10°C for 10 minutes, so that the flame was emitted toward the insulating sheet within a distance of 5 cm, and changes such as the collapse of the fire-resistant layer and its internal structure were observed. The side surface portion of the insulating sheet was cut into a size of 20 x 60 mm, and each insulating sheet was evaluated by measuring the toughness representing the energy storage value through a 3-point bending test using a universal testing machine (UTM) until the sheet finally broke or ruptured. The measured values ​​of toughness are shown in Table 1 below. Photos of Example 1, Example 4 and Example 8 and Comparative Example 1 after emitting the flame are shown in Table 1. Figure 7 middle.

[0187] [Table 1]

[0188]

[0189] Referring to Table 1, which shows the results of measuring the toughness (which is the mechanical durability) of Examples 1 to 3 after flame emission depending on the type of inorganic binder, it can be seen that when calcium silicate, calcium aluminate or aluminum phosphate is used as an inorganic binder, the fire resistance is desired, advantageous or improved.

[0190] From the results of the evaluation of the fire resistance of Example 1 and Example 4 depending on the fire-resistant layer forming method, it can be seen that the dispensing printing method forms a more uniform and dense fire-resistant layer than the brush coating method, achieving better fire resistance.

[0191] As can be seen from Example 5, when the fire-resistant layer is formed on the upper side surface portion and the lower side surface portion of the side surface of the insulating sheet, the toughness is further improved. As can be seen from Example 6, the fire-resistant layer is formed on the entire side surface of the insulating sheet, thereby the toughness is somewhat improved, but since the degree of improvement in toughness is small compared to the degree of formation of the fire-resistant layer, the cost-effectiveness will be slightly lower. As can be seen from Example 7, when the fire-resistant layer is formed on the upper side surface portion and the lower side surface portion of the side surface of the insulating sheet so that the thickness of the fire-resistant layer formed on the upper side surface portion is greater than the thickness of the fire-resistant layer formed on the lower side surface portion, the toughness is further improved.

[0192] It can be seen from Example 8 that when the fire-resistant layer is formed on the upper surface portion and the lower surface portion of the side surface of the insulating sheet, and the fire-resistant layer is formed into a trapezoidal shape to wrap a portion of the side surface of the battery cell adjacent to the upper surface portion of the side surface of the insulating sheet, the toughness is effectively improved.

[0193] As can be seen from Comparative Example 1 including no fire-resistant layer, the fire resistance is very low.

[0194] The internal photographs of the insulating sheets of Examples 1 to 4, Example 8 and Comparative Example 1 after the fire resistance measurement are shown in Figure 7 In. Figure 7 As shown in FIG. 1 , it can be seen from the internal structure of the embodiment that the fire resistance of the side surface of the insulation sheet is desirable, advantageous or improved due to the formation of the fire-resistant layer.

[0195] It can be seen from Comparative Example 1 that the side surface of the insulating sheet has low fire resistance and durability, and is structurally fragile. It can be seen from Examples 1, 4, and 8 that fire resistance is desirable, advantageous, or improved, whereby combustion does not occur, and structural stability is desirable, advantageous, or improved, whereby thermal insulation is also desirable, advantageous, or improved.

[0196] Experimental Example 2: Evaluation of Thermal Runaway Delay

[0197] The thermal runaway delay of each of the insulating sheets manufactured in Examples 1 to 8 and Comparative Example 1 was evaluated.

[0198] Using a simple module device consisting of three prismatic battery cells, the insulation sheet was fastened between the battery cells under a fastening pressure of 15 kN, and each insulation sheet was subjected to a thermal runaway test by artificial thermal runaway by heating the heating pad attached to the exploded battery cell (temperature rise 20°C / min), and the thermal runaway delay time (s) was measured. The results of the measurement are shown in Table 2 below. The temperature changes over time of Example 1 and Example 4 and Comparative Example 1 are shown in Figure 8 middle.

[0199] [Table 2]

[0200]

[0201] Referring to Table 2, which shows the results of evaluation of thermal runaway delay of Examples 1 to 3 depending on the type of inorganic binder, it can be seen that when calcium silicate, calcium aluminate or aluminum phosphate is used as the inorganic binder, the thermal runaway delay effect is desirable, advantageous or improved.

[0202] From the results of the evaluation of the thermal runaway delay of Examples 1 and 4 depending on the method of forming the refractory layer, it can be seen that when a uniform and dense refractory layer is formed by the dispensing printing method, the thermal runaway delay effect is better. Figure 8 It can also be seen that in Examples 1 and 4, the temperature rise of adjacent battery cells during thermal runaway is not instantaneous but delayed due to the formation of the fire-resistant layer, and in Example 1, the temperature rise is further delayed during thermal runaway.

[0203] From the results of the evaluation of the thermal runaway delay of Examples 1 and Examples 5 to 8 depending on the position and shape of the refractory layer, it can be seen that when the refractory layer is formed on the upper side surface portion of the boundary side surface of the insulating sheet, when the refractory layer is formed on the upper side surface portion and the lower side surface portion of the boundary side surface of the insulating sheet and the thickness of the refractory layer formed on the upper side surface portion is equal to the thickness of the refractory layer formed on the lower side surface portion, when the refractory layer is formed on the entire side surface of the insulating sheet, or when the refractory layer is formed on the upper side surface portion and the lower side surface portion of the side surface of the insulating sheet and the thickness of the refractory layer formed on the upper side surface portion is greater than the thickness of the refractory layer formed on the lower side surface portion, a better thermal runaway delay effect is obtained. It can also be seen that when the refractory layer is formed on the upper side surface portion and the lower side surface portion of the boundary side surface of the insulating sheet, and the refractory layer is formed in a trapezoidal shape to wrap a portion of the side surface of the battery cell adjacent to the upper side surface portion of the side surface of the insulating sheet, effective thermal runaway delay is possible.

[0204] From Table 2 and Figure 8 It can be seen that in Comparative Example 1, it is difficult to delay thermal runaway because the reinforcing material is not included and the temperature rise of the adjacent battery cells is immediate.

[0205] As apparent from the above description, a battery module according to example embodiments may suppress propagation of heat and flame in a battery cell to battery cells adjacent thereto due to thermal runaway in the battery cell.

[0206] The insulating sheet included in the battery module according to example embodiments may have desired, advantageous or improved thermal insulation, compressibility, mechanical strength and dimensional stability, thereby being able to prevent the aerogel layer from falling off due to external impact, improve operability, and prevent instrument contamination.

[0207] Although the foregoing describes example embodiments, the present disclosure is not limited thereto, and it is contemplated that various modifications may be made within the scope of the claims, detailed description of example embodiments, and the accompanying drawings, and that these modifications also fall within the scope of the present disclosure.

Claims

1. A battery module, comprising: Multiple battery cells; an insulating sheet between the plurality of battery cells, the insulating sheet having an upper surface and a lower surface facing the battery cells adjacent thereto, respectively; as well as a fire-resistant layer on at least one side surface portion of a boundary side surface between the upper surface and the lower surface of the insulating sheet, the at least one side surface portion comprising an upper side surface portion, a lower side surface portion, a front side surface portion, and a rear side surface portion, wherein The fire-resistant layer includes an inorganic binder. 2 . The battery module according to claim 1 , wherein at least one of the plurality of battery cells is a secondary battery cell.

3. The battery module according to claim 1, wherein the insulating sheet comprises: a first substrate; a second substrate; as well as An aerogel layer is between the first substrate and the second substrate. 4 . The battery module according to claim 3 , wherein at least one of the first substrate and the second substrate comprises at least one of a resin, a metal, an inorganic material other than the metal, and a composite thereof. 5 . The battery module according to claim 3 , wherein the aerogel layer comprises at least one of an aerogel, a fiber support and a functional material, and the functional material comprises at least one of a binder, a dispersant and a combination thereof.

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

7. The battery module of claim 5, wherein the fiber support comprises at least one of natural fiber, silica fiber, glass fiber, ceramic fiber, carbon fiber, graphite fiber, mineral fiber and polymer fiber.

8. The battery module according to claim 5, wherein The binder comprises an aqueous polymer binder, and The aqueous polymer binder includes at least one of a water-based polymer, an anionic water-soluble polymer, a cationic water-soluble polymer, and a water-dispersible polymer.

9. The battery module according to claim 5, wherein the dispersant comprises at least one of a surfactant and a phosphate salt.

10. The battery module according to claim 5, wherein based on the total amount of the aerogel layer, the aerogel accounts for 10 wt% to 90 wt%, the fiber support accounts for 5 wt% to 70 wt%, and the functional material accounts for 0.5 wt% to 20 wt%.

11. The battery module of claim 1, wherein the inorganic binder comprises at least one of aluminate, silicate, phosphate, sulfate and chloride.

12. The battery module of claim 1, wherein the inorganic binder comprises at least one of calcium aluminate, calcium silicate, 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 of claim 1, wherein the fire-resistant layer is formed on at least one of an upper surface portion and a lower surface portion of the boundary side surface of the insulation sheet, or on substantially the entire boundary side surface of the insulation sheet.

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

15. The battery module according to claim 1, wherein The battery module includes a void area except for a space in which the battery cell and the insulating sheet are disposed, The fire-resistant layer wraps a part or all of the boundary side surface of the insulating sheet and the side surface of each battery cell adjacent thereto in the gap area formed at the upper portion of the battery module, and The fire-resistant layer is formed such that a thickness of a central portion of the fire-resistant layer is greater than a thickness of opposite edges of the fire-resistant layer.

16. A method for manufacturing a battery module, the method comprising: Arrange a plurality of battery cells; Disposing an insulating sheet between the plurality of battery cells, such that an upper surface and a lower surface of the insulating sheet are respectively disposed to face the battery cells adjacent thereto; as well as A fire-resistant layer is formed on at least one side surface portion of a boundary side surface between the upper surface and the lower surface of the insulating sheet, wherein The fire-resistant layer includes an inorganic binder.

17. The method of claim 16, wherein the refractory layer is formed by at least one of gap coating, dip coating, slot die coating, doctor blading, dispensing printing, brush coating, and embedding using a solution in which the inorganic binder is dispersed in a solvent.

18. A battery pack comprising the battery module according to any one of claims 1 to 15 or a battery module manufactured by the method according to claim 16 or 17.

Images