Heat insulating member

Abstract

The present invention relates to a heat insulating member, and a battery module and a battery pack each comprising same, wherein the heat insulating member comprises a silica heat insulating composite having excellent heat resistance, thereby minimizing the deterioration of heat blocking performance in a high-temperature environment even when sealed with a film.

Description

Insulating member

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0178813 filed December 4, 2024 and U.S. Patent Application No. 19 / 405,757 filed December 2, 2025, and all contents disclosed in the documents of said patent applications are incorporated herein as part of this specification.

[0003] The present invention relates to an insulating member.

[0004] Silica insulation sheets containing a silica network structure in the fibers are widely used in construction or industrial sites, and recently, in particular, are also being applied as insulation materials for batteries in electric vehicles.

[0005] Batteries used in electric vehicles and the like are high-output, high-capacity batteries that generate a significant amount of heat during the charging and discharging process. If this generated heat is not effectively removed, the risk of ignition or explosion increases due to heat accumulation. Therefore, to prevent thermal runaway, silica insulation sheets can be interposed between battery cells to provide a heat-blocking effect.

[0006] However, when applying silica insulation sheets to batteries, it is essential to encapsulate the entire surface of the sheet with a film to prevent silica particles from leaking out. PET films are primarily used for this purpose, but such films have a lower heat resistance temperature and generate more heat compared to silica insulation sheets. Therefore, sealing the silica insulation sheet with a film degrades its thermal insulation performance.

[0007] Accordingly, there is a need to develop a silica insulation sheet that further enhances the thermal insulation performance of the silica insulation sheet, thereby preventing or minimizing the degradation of the silica insulation sheet's thermal insulation performance in high-temperature environments even when the silica insulation sheet is sealed with a film.

[0008] One objective of the present invention is to provide a silica thermal insulation composite in which the degradation of thermal insulation performance is minimized even when sealed with a film, and a thermal insulation member including the same.

[0009] Another objective of the present invention is to provide a battery module and a battery pack comprising the above-described insulating member.

[0010] However, the technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below.

[0011] According to one embodiment of the present invention, the invention relates to an insulating member comprising a silica insulating composite including a substrate and a silica network structure; and a film surrounding the silica insulating composite, wherein when heat of 700°C is applied to a first surface of the insulating member, the 180°C heat resistance index (A) represented by the following Formula 1 is 50% or more:

[0012] [Equation 1]

[0013]

[0014] In the above Equation 1, the time to reach 180°C (seconds) of the insulating member refers to the time (seconds) when the temperature of the second surface of the insulating member reaches 180°C, and the time to reach 180°C (seconds) of the silica insulating composite refers to the time (seconds) when the temperature of the second surface of the silica insulating composite reaches 180°C when heat of 700°C is applied to the first surface of the silica insulating composite that is not surrounded by a film.

[0015] The above silica network structure includes a plurality of silica particles and may include one or more pores.

[0016] The time (in seconds) required for the temperature of the second surface of the above-mentioned insulating member to reach 180°C may be 15 seconds or more.

[0017] When heat of 700 ℃ is applied to the first surface of the above-mentioned insulating member, the 350 ℃ heat resistance index (B) expressed by the following Equation 2 may be 50% or more:

[0018] [Equation 2]

[0019]

[0020] In the above Equation 2, the time (seconds) to reach 350 ℃ of the insulating member refers to the time (seconds) for the temperature of the second surface of the insulating member to reach 350 ℃, and the time (seconds) to reach 350 ℃ of the silica insulating composite refers to the time (seconds) for the temperature of the second surface of the silica insulating composite to reach 350 ℃ when heat of 700 ℃ is applied to the first surface of the silica insulating composite that is not surrounded by a film.

[0021] The time (in seconds) required for the temperature of the second surface of the above-mentioned insulating member to reach 350°C may be 100 seconds or more.

[0022] The above film may have a heat generation capacity of 1,500 to 3,000 J / g.

[0023] The thickness of the above silica thermal insulation composite may be 0.5 to 10 mm.

[0024] The above silica network structure may include silica, methylsilylated silica, dimethylsilylated silica, trimethylsilylated silica, or a mixture thereof.

[0025] The above silica thermal insulation composite may include particles in which a plurality of silica particles with a particle size greater than 0 and less than or equal to 5 nm are aggregated or bonded.

[0026] The average particle size of the aggregated or combined particles may be 5 to 2,000 nm.

[0027] The density of the above silica thermal insulation composite is 0.05 to 0.50 g / cm³ 3 It could be.

[0028] The above silica network structure may include silica aerogel or be silica aerogel.

[0029] The above silica thermal insulation composite may be an aerogel composite comprising a substrate and a silica aerogel having a plurality of open pores.

[0030] According to another embodiment of the present invention, the invention relates to a battery module comprising one or more battery cells in an internal space; and the insulating member.

[0031] According to another embodiment of the present invention, the invention relates to a battery pack comprising a battery module including one or more battery cells in an internal space; and the insulating member.

[0032] Generally, when a PET film with a low heat resistance temperature and high heat generation is laminated onto a silica insulation composite, a problem arises in which the thermal insulation performance of the silica insulation composite is significantly degraded in high-temperature environments. However, the silica insulation composite provided in the present invention can maintain a high level of thermal insulation performance in high-temperature environments even when a film is laminated on its outer surface.

[0033] FIG. 1 is a perspective view of an insulating member according to one example.

[0034] FIG. 2a is a perspective view of an insulating member according to one example.

[0035] FIGS. 2b and 2c are cross-sectional views of an insulating member according to one example.

[0036] FIG. 3 is a front view of an insulating member according to one example.

[0037] FIG. 4 is a perspective view of an insulating member according to one example.

[0038] Figures 5 and 6 illustrate the cross-sectional structure of an example of equipment that can be used for heat transfer evaluation experiments.

[0039] According to one embodiment of the present invention, a silica thermal insulation composite comprising a substrate and a plurality of silica particles and a silica network structure comprising one or more pores; and a thermal insulation member comprising a film located on both sides of the silica thermal insulation composite, wherein when heat of 700°C is applied to the first surface of the thermal insulation member, the 180°C heat resistance index (A) represented by the following formula 1 may be 50% or more.

[0040] [Equation 1]

[0041]

[0042] In the above Equation 1, the time to reach 180°C (seconds) of the insulating member refers to the time (seconds) when the temperature of the second surface of the insulating member reaches 180°C, and the time to reach 180°C (seconds) of the silica insulating composite refers to the time (seconds) when the temperature of the second surface of the silica insulating composite reaches 180°C when heat of 700°C is applied to the first surface of the silica insulating composite without a laminated film.

[0043] The time (in seconds) required for the temperature of the second surface of the above-mentioned insulating member to reach 180°C may be 15 seconds or more.

[0044] When heat of 700 ℃ is applied to the first surface of the above-mentioned insulating member, the heat resistance index (B) of 350 ℃, expressed by the following formula 2, may be 50% or more.

[0045] [Equation 2]

[0046]

[0047] In the above Equation 2, the time to reach 350 ℃ (seconds) of the insulating member refers to the time (seconds) when the temperature of the second surface of the insulating member reaches 350 ℃, and the time to reach 350 ℃ (seconds) of the silica insulating composite refers to the time (seconds) when the temperature of the second surface of the silica insulating composite reaches 350 ℃ when heat of 700 ℃ is applied to the first surface of the silica insulating composite without a laminated film.

[0048] The time (in seconds) required for the temperature of the second surface of the above-mentioned insulating member to reach 350°C may be 100 seconds or more.

[0049] The above film may have a heat generation capacity of 1,500 to 3,000 J / g.

[0050] The thickness of the above silica thermal insulation composite may be 0.5 to 10 mm.

[0051] The above silica particles may include silica, methylsilylated silica, dimethylsilylated silica, trimethylsilylated silica, or a mixture thereof.

[0052] The silica network structure within the above silica thermal insulation composite may include particles in which multiple silica particles with a particle size greater than 0 and less than or equal to 5 nm are aggregated or bonded.

[0053] The average particle size of the aggregated or combined particles may be 5 to 2,000 nm.

[0054] The density of the above silica thermal insulation composite is 0.05 to 0.50 g / cm³ 3 It could be.

[0055] The above insulating member may be in the form of a sheet.

[0056] According to another embodiment of the present invention, the invention relates to a battery module comprising one or more battery cells in an internal space; and the insulating member.

[0057] According to another embodiment of the present invention, the invention relates to a battery pack comprising the battery module described above.

[0058] Hereinafter, the present invention will be described in more detail to aid in understanding the invention. In this case, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0059]

[0060] According to one embodiment of the present invention, the invention relates to a thermal insulation member comprising a silica thermal insulation composite including a substrate and a silica network structure; and a film located on both sides of the silica thermal insulation composite.

[0061] The above silica network structure comprises a plurality of silica particles and includes one or more pores, and refers to a network structure formed by connecting a plurality of silica particles in three dimensions. This structure forms a plurality of continuous pores between the silica particles, and these pores are connected to each other and distributed throughout the structure.

[0062] The silica particles may comprise silica, methylsilylated silica, dimethylsilylated silica, trimethylsilylated silica, or a mixture thereof. Additionally, the silica particles may comprise primary particles having a size of approximately greater than 0 and less than 10 nm, or greater than 0 and less than 5 nm, preferably around 1 nm, and secondary particles formed by the aggregation of these particles. The secondary particles may have an average particle size of approximately 5 to 2,000 nm, 5 to 1,000 nm, 5 to 500 nm, 5 to 100 nm, or 5 to 50 nm, but are not limited thereto. The average particle size may be measured by any means known to those skilled in the art, such as scanning electron microscopy, dynamic light scattering, optical microscopy, or size exclusion methods, but is not limited thereto.

[0063] The pores included in the above silica network structure may include mesopores, or may include micropores or macropores. Here, the "mesopore" is a pore with an average pore diameter in the range of about 2 nm to about 50 nm, the "macropore" is a pore with an average pore diameter exceeding about 50 nm, and the "micropore" is a pore with an average pore diameter less than about 2 nm. The silica network structure may include at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% mesopores of the pore volume. The silica network structure may include mesopores. The silica network structure may include mesopores and micropores. The above pore size can be measured by any means known to those skilled in the art, such as gas adsorption experiments, mercury infiltration, capillary flow porometry, or positron annihilation lifetime spectroscopy (PALS), but is not limited thereto.

[0064] The above silica network structure is not particularly limited as long as it includes silica particles and has the above-described network structure, but may include aerogel.

[0065] The above "aerogel" comprises a plurality of primary aerogel particles having a size of approximately greater than 0 and less than 10 nm, greater than 0 and less than 5 nm, and secondary aerogel particles formed by the aggregation or bonding of these primary aerogel particles, and as a plurality of open pores are formed between the primary aerogel particles and between the secondary aerogel particles to form aggregates, the aerogel forms a three-dimensional network structure.

[0066] The above aerogel may be an inorganic silica aerogel formed from a silicon alkoxide-based compound or water glass as a precursor. In one example, the aerogel may comprise silica, methylsilylated silica, dimethylsilylated silica, trimethylsilylated silica, or a mixture thereof. In another example, the aerogel may have at least some of the SiO2 on the surface of the SiO2 network structure having a bonding structure of Si-O-SiO2(CH3), Si-O-SiO(CH3)2, or Si-O-Si(CH3)3. The specific manufacturing process of the silica aerogel is described in detail below.

[0067] The above substrate may be a fiber substrate comprising a plurality of fibers. The silica thermal insulation composite has a structure in which at least some of a plurality of silica particles (or aerogel particles) are dispersed, preferably bonded, on the surface of the fibers within the substrate, and at the same time, at least some of a plurality of silica particles (or aerogel particles) are dispersed, preferably located, in the empty spaces between the dispersed fibers within the substrate.

[0068] The above "aerogel particles" are particles in the form of individual solid units constituting the aerogel, and may include primary aerogel particles having a size of approximately greater than 0 and less than 10 nm, or greater than 0 and less than 5 nm, preferably around 1 nm, and secondary aerogel particles formed by the aggregation of these particles. However, the aerogel within the silica insulation composite is mostly in the form of secondary aerogel particles or aggregated and bonded thereof, and a small amount of primary aerogel particles that do not form secondary aerogel particles may be mixed in. The above secondary aerogel particles may have an average particle size of approximately 5 to 2,000 nm, 5 to 1,000 nm, 5 to 500 nm, 5 to 100 nm, or 5 to 50 nm, but are not limited thereto. In the present invention, the average particle size may be measured by any means known to those skilled in the art, such as scanning electron microscopy, dynamic light scattering, optical microscopy, or size exclusion methods, but is not limited thereto.

[0069] The aerogel may have a matrix framework structure including mesopores, and may include micropores or macropores in addition to the mesopores. The aerogel may contain at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% mesopores of the pore volume of the framework structure. The aerogel may include mesopores. The aerogel may include mesopores and micropores. The pore size may be measured by any means known to those skilled in the art, such as gas adsorption experiments, mercury infiltration, capillary flow porometry, or positron annihilation lifetime spectroscopy (PALS), but is not limited thereto.

[0070] Examples of the above-described materials may include discrete fibers, films, sheets, nets, fibers, porous materials, foams, nonwoven materials, or laminates of two or more layers thereof. Additionally, depending on the application, the surface may have a surface roughness or be patterned.

[0071] The above description refers to polyester, polyolefin terephthalate, poly(ethylene) naphthalate, polycarbonate, regenerated cellulose (e.g., rayon), polyamide (e.g., nylon), cotton, spandex (e.g., Lycra from DuPont), carbon (e.g., graphite), polyacrylonitrile (PAN), PAN oxide, non-carbonized heat-treated PAN (e.g., from SGL Carbon), glass fiber-based materials (S-glass, 901 glass, 902 glass, 475 glass, E-glass, etc.), silica-based fibers, e.g., quartz (e.g., Saint-Gobain Quartzel), Q-felt (from Johns Manville), Saffil (from Safil), Durablanket (from Uniflex), and other silica fibers, Duraback (from carborundum), polyaramid fibers, e.g., Kevlar, Nomex, Sontera (all from DuPont), Conex (from Tyzine), polyolefins, e.g., Tyvek (from DuPont It may include polypropylene fibers such as Typar and Xavan (both DuPont), fluoropolymers such as PTFE under the brand name Teflon (DuPont), Goretex (WL GORE), silicon carbide fibers such as Nicalcon (COI Ceramics), ceramic paper, ceramic fibers such as Nextel (3M), acrylic polymers, basalt fibers, wool, silk, hemp, leather, suede fibers, PBO-Xylon fibers (Tybo), liquid crystal materials such as Vectran (Hoechst), Cambrel fibers (DuPont), polyurethane, wool fibers, boron, aluminum, iron, stainless steel fibers, or other thermoplastic resins such as PEEK, PES, PET, PEK, PPS, but may be used without limitation as long as the fiber contains a silica three-dimensional structure or a space or void that facilitates the insertion of aerogel, thereby further improving thermal insulation performance.As an example, the above description may include glass fibers, basalt fibers, ceramic fibers and / or ceramic paper, but is not limited thereto.

[0072] The thickness of the above-mentioned substrate may be 0.5 mm or more, 1 mm or more, 1.5 mm or more, 2 mm or more, 2.5 mm or more, or 3 mm or more, and may be 20 mm or less, 15 mm or less, 10 mm or less, 9 mm or less, 8 mm or less, 7 mm or less, 6 mm or less, 5 mm or less, 4 mm or less, 3.5 mm or less, or 3 mm or less. For example, the thickness of the above-mentioned substrate may be 0.5 to 20 mm, 0.5 to 10 mm, 0.5 to 5 mm, 0.5 to 4 mm, or 0.5 to 3.5 mm, but is not limited thereto.

[0073] The above silica insulation composite may have a rectangular shape in which a substrate and a silica network structure (e.g., aerogel) are mixed from the top surface to the bottom surface, but is not limited thereto.

[0074] In addition, at least a portion of the upper or lower surface of the silica insulation composite, preferably the entire surface, may have a flat shape. Here, the "flat shape" means that no irregularities are formed by intentional embossing or coating processes. In the present invention, forming the upper and lower surfaces of the silica insulation composite flat as described above can improve ease of operation when laminating support members, such as sheets, onto the upper and lower surfaces, and can increase the adhesion retention rate of the support members. Furthermore, it is desirable to reduce friction with adjacent equipment surfaces even when the silica insulation composite itself is applied directly as an insulation member without support members.

[0075] In addition, the thickness of the silica thermal insulation composite may be 0.5 mm or more, 1 mm or more, 1.5 mm or more, 2 mm or more, 2.5 mm or more, or 3 mm or more, and may be 20 mm or less, 15 mm or less, 10 mm or less, 9 mm or less, 8 mm or less, 7 mm or less, 6 mm or less, 5 mm or less, 4 mm or less, 3.5 mm or less, or 3 mm or less. For example, the thickness of the silica thermal insulation composite may be 0.5 to 20 mm, 0.5 to 10 mm, 0.5 to 5 mm, 0.5 to 4 mm, or 0.5 to 3.5 mm, but is not limited thereto.

[0076] The density of the above silica thermal insulation composite is 0.05 to 0.50 g / cm³ 3 , 0.05 to 0.35 g / cm² 3 , 0.05 to 0.30 g / cm² 3 , 0.10 to 0.35 g / cm² 3 , 0.10 to 0.30 g / cm² 3 , 0.15 to 0.35 g / cm² 3 1 or 0.15 to 0.30 g / cm² 3 It may be, but is not limited to this.

[0077] The above silica insulation composite may have a thermal conductivity of 30.0 mW / mK or less, 25.0 mW / mK or less, or 20.0 mW / mK or less at room temperature (23±2 ℃), and within this range, the thermal insulation performance of the silica insulation composite can be maximized.

[0078] The above silica insulation composite may have a high temperature (150 ℃) thermal conductivity of 35.0 mW / mK or less, 30.0 mW / mK or less, or 25.0 mW / mK or less, and within this range, the thermal insulation performance of the silica insulation composite can be maximized.

[0079] The above silica thermal insulation composite may have excellent mechanical strength, with a compressive strength at 10% deformation of 20 kPa to 80 kPa, 20 kPa to 70 kPa, 30 kPa to 80 kPa, 30 kPa to 70 kPa, 35 kPa to 80 kPa, or 35 kPa to 70 kPa. Here, the compressive strength may be measured by manufacturing a specimen according to ASTM C165.

[0080] The above silica thermal insulation composite has a tensile strength of 30 N / cm 2 up to 60 N / cm 2 , 40 N / cm 2 Up to 55 N / cm 2 , or 45 N / cm 2 Up to 55 N / cm 2 As such, it may have excellent flexibility. Here, the tensile strength may be measured by manufacturing a specimen according to ASTM D638 standards.

[0081] The dielectric breakdown strength of the above silica insulation composite at room temperature (23±2 ℃) is 3 kV / mm or more, 4 kV / mm or more, or 5 kV / mm or more, and although the upper limit is not specifically limited, it may be about 30 kV / mm or less, 25 kV / mm or less, 20 kV / mm or less, or 15 kV / mm or less. Here, the dielectric breakdown strength may be measured according to ASTM D149 standards.

[0082] The surface resistance of the above silica thermal insulation composite at room temperature (23±2 ℃) is 1 X 10⁻⁶ 10 Ω / sq or greater, 1 X 10 11 Ω / sq or more or 1 x 10⁻⁶ 12 It can be greater than Ω / sq. Also, the volume resistance is 1 x 10⁻⁶ 10 Ω·cm or greater, 1 X 10⁻⁶ 11 Ω·cm or more or 1 x 10⁻⁶ 12The above surface resistance and volume resistance were measured by applying a voltage of 1,000 V for 60 seconds to one of the two sides of the silica thermal insulation composite using a resistivity meter (Hiresta UX MCP-HT800, Mitsubishi Chemical Analytech).

[0083] A film may be positioned on both sides of the above-described silica insulating composite. Additionally, a film may be positioned on the side surface in the thickness direction of the silica insulating composite. Therefore, the silica insulating composite may have a structure encapsulated by a film.

[0084] The above film may comprise polyethylene (PE) resin, polyethylene terephthalate (PET) resin, polypropylene (PP) resin, or a mixture thereof. As an example, the above film may be a PET film, but is not limited thereto.

[0085] The thickness of the above film is not particularly limited, but, for example, it may be 0.1 to 100 μm, 1 to 100 μm, 10 to 100 μm, 1 to 50 μm, 10 to 50 μm, or 25 to 40 μm.

[0086] In addition, an adhesive layer or an adhesive layer may be located on the opposite side of the silica thermal insulation composite among the two sides of the above film.

[0087] The above adhesive layer or adhesive layer may include, but is not limited to, an acrylic adhesive, a polyurethane adhesive, an olefin adhesive, an SBR rubber adhesive, or a silicone adhesive.

[0088] The thickness of the adhesive layer or the adhesive layer is not particularly limited and, for example, may be 0.1 to 100 μm, 1 to 100 μm, 10 to 100 μm, 1 to 50 μm, 10 to 50 μm, or 25 to 50 μm.

[0089] The above film may have a heat generation amount of 1,000 to 3,500 J / g, 1,100 to 3,000 J / g, 1,500 to 3,000 J / g, 2,000 to 3,000 J / g, or 2,500 to 3,000 J / g, but is not limited thereto.

[0090] In addition, the thickness of the insulation member may be 0.5 mm or more, 1 mm or more, 1.5 mm or more, 2 mm or more, 2.5 mm or more, or 3 mm or more, and may be 20 mm or less, 15 mm or less, 10 mm or less, 9 mm or less, 8 mm or less, 7 mm or less, 6 mm or less, 5 mm or less, 4 mm or less, 3.5 mm or less, or 3 mm or less. For example, the thickness of the insulation member may be 0.5 to 20 mm, 0.5 to 10 mm, 0.5 to 5 mm, 0.5 to 4 mm, or 0.5 to 3.5 mm, but is not limited thereto.

[0091] FIG. 1 illustrates a perspective view of an insulating member according to one example, in which a film (200) cut into a shape corresponding to the upper and lower surfaces of a rectangular sheet-shaped silica insulating composite (100) is laminated. FIG. 2a illustrates a perspective view of an insulating member according to one example, and FIG. 2b and FIG. 2c illustrate a longitudinal cross-sectional view and a width cross-sectional view, respectively. The long cut film (200) is arranged to surround the upper surface, side, lower surface, and other side of the silica insulating composite (100; dotted line) in the width direction (A direction). Another cut film (200') is arranged to surround the upper surface, side, lower surface, and other side of the silica insulating composite in the length direction (B direction), which is orthogonal to the width direction (A direction). Accordingly, two layers of film (200, 200') are laminated on the upper and lower surfaces of the silica insulation composite, while a single layer of film (200 or 200') is laminated on the side of the silica insulation composite. At this time, the two ends of a single film may be joined together at the corners of the silica insulation composite (or at any arbitrary location). Although not shown in the drawings, a sealing portion may exist where the two ends overlap each other. FIG. 3 shows a front view of an insulation member according to another example, in which a silica insulation composite (100) is accommodated inside a folded film (200), and a sealing portion (S1) is formed by joining a film along the outer edge of the silica insulation composite. Although not shown in the drawings, a structure in which a silica insulation composite is interposed between two films and a sealing portion is formed by the two films being joined along the outer edge of the silica insulation composite is also included within the scope of the present invention.FIG. 4 illustrates a perspective view of an insulating member according to another example, wherein a silica insulating composite (100) is positioned inside a film (200), and then the film (200) is folded to surround all sides of the silica insulating composite (100) in accordance with the shape of the silica insulating composite (100), and the two ends of the film (200) overlap on one side of the silica insulating composite (100) to form a sealing portion (S2).

[0092] When silica insulation composites, such as aerogel blankets, are applied as insulating materials in batteries for electric vehicles, they are typically used in a structure where they are encased in a film to address issues like dust generation. However, polymer films, such as PET, have lower heat resistance temperatures and higher heat generation compared to silica insulation composites. Consequently, when the insulating material is exposed to high-temperature environments, the heat generated by the film can cause the pores of the silica insulation composite to collapse or partially melt, potentially blocking or destroying the pores. As a result, the thermal insulation performance of the silica insulation composite within the insulating material deteriorates significantly due to various causes in high-temperature environments. Therefore, there is a need to develop silica insulation composites that minimize the degradation of thermal insulation performance in high-temperature environments, even when encased in a film.

[0093] Even if the silica insulation composite itself has excellent heat resistance, if the internal pores are not firmly formed or the strength of the three-dimensional network structure (matrix structure) is low, the film, which is partially melted in a high-temperature environment, can easily penetrate into the pores of the silica insulation composite, causing the pores to become blocked and collapse. Alternatively, even if the film does not melt, the pores may collapse due to the high heat generation of the film, ultimately leading to a significant decrease in the thermal insulation performance of the silica insulation composite.

[0094] As a result of diligent efforts, the inventors have developed a silica insulation composite that not only exhibits excellent heat resistance but also possesses superior pore strength. Consequently, even when heat is applied to a film surrounding the silica insulation composite, the blockage or destruction of the pores of the silica insulation composite is suppressed, thereby minimizing the degradation of heat insulation performance, leading to the present invention. Such effects can still be expected even if the composition of the film or the amount of heat generated changes.

[0095] In the present invention, the heat resistance of the insulating member was evaluated by applying heat of 700°C to the first surface of the insulating member and measuring the time required for the temperature on the opposite surface of the insulating member to rise to 180°C or a higher temperature of 350°C. Here, the 180°C is a temperature closely related to the melting point of a typical battery separator; exceeding this temperature can damage the separator, leading to thermal runaway and safety issues. Therefore, evaluating the ability of the insulating material to delay the temperature rise to 180°C is crucial for improving battery safety. This heat resistance index can be utilized as an indicator to quantitatively compare the thermal resistance performance of various insulating material designs and serves as an important evaluation criterion when selecting materials for next-generation battery systems.

[0096] Specifically, in an insulating member comprising a film surrounding the front surface of the above-described silica insulating composite, the time (in seconds) for the temperature of the second surface of the insulating member to reach 180°C when heat of 700°C is applied to the first surface of the insulating member is characterized by being at least 50% of the time (in seconds) for the temperature of the second surface of the silica insulating composite to reach 180°C when heat of 700°C is applied to the first surface of the silica insulating composite that is not surrounded (the front surface) by the film. Such a characteristic can be expressed by Equation 1 below.

[0097] [Equation 1]

[0098]

[0099] In the above Equation 1, the heat resistance index (A) at 180°C may be 50% or more, 55% or more, 60% or more, 65% or more, or 70% or more.

[0100] The time (in seconds) required for the temperature of the second surface of the above-mentioned insulating member to reach 180°C may be 15 seconds or more, 15.5 seconds or more, 16 seconds or more, 17 seconds or more, 18 seconds or more, 19 seconds or more, or 20 seconds or more.

[0101] In addition, the time (in seconds) for the temperature of the second surface of the insulating member to reach 350°C when heat of 700°C is applied to the first surface of the insulating member of the present invention is characterized by being at least 50% of the time (in seconds) for the temperature of the second surface of the silica insulating composite to reach 350°C when heat of 700°C is applied to the first surface of the silica insulating composite that is not surrounded by a film. Such a characteristic can be expressed by Equation 2 below.

[0102] [Equation 2]

[0103]

[0104] In the above Equation 2, the heat resistance index (B) at 350°C may be 50% or more, 51% or more, 52% or more, 54% or more, 56% or more, 58% or more, or 60% or more.

[0105] The time (in seconds) required for the temperature of the second surface of the above-mentioned insulating member to reach 350 ℃ may be 100 seconds or more, 105 seconds or more, 110 seconds or more, 115 seconds or more, or 120 seconds or more.

[0106] In this specification, “first surface” and “second surface” are terms used to distinguish surfaces facing each other based on the thickness direction of a sheet-shaped silica insulation composite. For example, the first surface to which heat is applied may be the externally exposed surface of a film laminated on the upper surface of the silica insulation composite, in which case the second surface for measuring temperature becomes the externally exposed surface of a film laminated on the lower surface of the silica insulation composite. Conversely, if the first surface to which heat is applied is the externally exposed surface of a film laminated on the lower surface of the silica insulation composite, the second surface for measuring temperature becomes the externally exposed surface of a film laminated on the upper surface of the silica insulation composite. As such, the designations of the first surface and the second surface are not limited to a structural upper-lower relationship, but are merely intended to distinguish the surface to which heat is applied from the surface on the opposite side where the temperature is measured.

[0107] In addition, in this specification, “time required for the temperature of the second side of the insulating member or silica insulating composite to reach 180 ℃ or 350 ℃” means the elapsed time from when heat of 700 ℃ is applied to the first side of the insulating member or silica insulating composite, and the temperature of the opposite side (i.e., the second side) to which heat is not directly applied reaches 180 ℃ or 350 ℃ from 50 ℃.

[0108] The method for measuring the time (in seconds) to reach a temperature of 180°C or 350°C by applying heat of 700°C to the above-mentioned insulating member and silica insulating composite is described as follows: First, the equipment for the heat transfer experiment may be used without limitation as long as it includes a heating device capable of applying heat to the first surface of a rectangular insulating member and a thermometer capable of measuring the temperature of the second surface of the insulating member. Figures 5 and 6 schematically illustrate the structure of an exemplary equipment that can be used for the heat transfer experiment. The above equipment may include an insulating board (1) on which a specimen is placed, a temperature sensor (2) located on the insulating board (1) and measuring the temperature of a first surface (10') that is in contact with the insulating board (1) among the two surfaces of the specimen (10), a heating plate (3) located opposite the insulating board (1) and heating the surface in contact with the insulating board and the second surface (10") among the two surfaces of the upper and lower surfaces of the specimen, and a pressing part (4) connected to the heating plate (3) and pressing the insulating board (1) in the direction of the heating plate (3). FIG. 5 illustrates a state in which the second surface (10") of the specimen is in contact with the heating plate (3) by adjusting the pressing part (4). As an insulating material specimen to perform a heat transfer experiment, a specimen in the shape of a rectangular parallelepiped with dimensions of approximately 75 mm x 75 mm in width x length is prepared. After placing an insulating material specimen on an insulating board, the specimen is left undisturbed until the temperature of the first surface of the specimen reaches 50°C or lower (e.g., room temperature of 25±5°C) using a temperature sensor located between the specimen and the insulating board. The heating plate is heated to 700°C, and the pressure is applied at a pressure of 500 kPa by adjusting the pressure unit so that the upper surface of the insulating material specimen comes into contact with the heating plate. The temperature of the lower surface of the specimen is measured using a temperature sensor located between the specimen and the insulating board, and the time (in seconds) required to reach 180°C or 350°C from the point when the temperature of the lower surface of the specimen reaches 50°C is measured.

[0109] The above heat resistance index is a percentage of the time it takes to reach the corresponding temperature in the insulating member relative to the time it takes to reach the corresponding temperature in the silica insulating composite, and is an indicator that reflects the thermal insulation performance of the silica insulating composite regardless of the thickness of each element constituting the insulating member. However, as an example, the above heat resistance index may be based on the thickness of the insulating member being 0.5 to 10 mm, preferably 1 to 5 mm, more preferably 1.5 to 3 mm, or 2 to 3 mm. As another example, the above heat resistance index may be based on the thickness of the silica insulating composite being 0.5 to 10 mm, preferably 1 to 5 mm, more preferably 1.5 to 3 mm, or 2 to 3 mm, and the thickness of the film to be laminated on the surface of the silica insulating composite being 10 to 100 μm, or 10 to 50 μm. As another example, the heat resistance index may be based on the thickness of the silica thermal insulation composite being 0.5 to 10 mm, preferably 1 to 5 mm, more preferably 1.5 to 3 mm, or 2 to 3 mm, the thickness of the film to be laminated on the surface of the silica thermal insulation composite being 10 to 100 μm, or 10 to 50 μm, and the thickness of the adhesive layer or adhesive layer to be placed between the surface of the silica thermal insulation composite and the film being 10 to 100 μm, or 10 to 50 μm.

[0110] The thermal insulation member with excellent heat-blocking performance provided by the present invention can be applied as a battery insulation material, but it can also be applied as an insulation material, thermal insulation material, or non-combustible material in the construction, aviation, automotive, home appliance, semiconductor, or industrial equipment fields.

[0111] The method for manufacturing an insulating member of the present invention may include the step of preparing a silica insulating composite; and the step of surrounding the silica insulating composite with a film.

[0112] The above silica thermal insulation composite can generally be formed by a step of preparing a silica sol; a gelation step after impregnating a substrate with the silica sol; and a drying step. Each step is described below. However, the specific manufacturing processes or examples described herein are not intended to limit any particular type of aerogel composite or its manufacturing method. This specification may include any silica thermal insulation composite formed by any associated manufacturing method known to a person skilled in the art.

[0113] Silica sol preparation steps

[0114] In the present invention, a silica sol can be prepared using a silica precursor composition.

[0115] The above silica precursor can be used without limitation as long as it is a precursor that can be used to form an aerogel, for example, with a silica three-dimensional network structure, and may be, for example, a silicon-containing alkoxide-based compound. Specifically, tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), methyl triethyl orthosilicate, dimethyl diethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetrasecondary butyl orthosilicate, tetra tertiary butyl orthosilicate, tetrahexyl orthosilicate, and tetracyclohexyl orthosilicate. It may be a tetraalkyl silicate such as tetradodecyl orthosilicate, tetradodecyl orthosilicate, etc., and preferably may be tetraethyl orthosilicate (TEOS), but is not limited thereto.

[0116] In addition, the silica precursor may be a water glass solution. Here, the water glass solution may refer to a diluted solution obtained by adding distilled water to water glass and mixing it, and the water glass may be sodium silicate (Na2SiO3), which is an alkali silicate obtained by melting silicon dioxide (SiO2) and an alkali.

[0117] In addition, the silica precursor may include pre-hydrolyzed TEOS (HTEOS). HTEOS is an ethyl silicate oligomer material with a broad molecular weight distribution, and since it can control physical properties such as gelation time when synthesized from TEOS monomers in the form of an oligomer, it can be easily applied according to the user's reaction conditions. Furthermore, it has the advantage of producing reproducible physical properties of the final product. The HTEOS may generally be synthesized by a condensation reaction of TEOS that has undergone a partial hydration step under acidic conditions. That is, the HTEOS may be in the form of an oligomer prepared by condensing TEOS, and the oligomer may be partially hydrated.

[0118] The above-mentioned fully hydrolyzed silica precursor can be prepared by mixing the silica precursor and an organic solvent in a weight ratio of 1:0.1 to 1.5, 1:0.5 to 1.5, or 1:0.5 to 1.2, but is not limited thereto.

[0119] In addition, the above-mentioned fully hydrolyzed silica precursor can be prepared by mixing the silica precursor and water in a molar ratio of 1:0.1 to 10, 1:1 to 8, or 1:2 to 6, but is not limited thereto.

[0120] The above silica precursor composition may further comprise a silicate containing a hydrophobic group. In the present invention, the silicate containing the hydrophobic group is not limited in type as long as it is an alkyl silane compound containing an alkyl group that induces hydrophobization and a silane functional group capable of reacting with the -Si-O- functional group of the wet gel; however, specific examples include one or more selected from the group consisting of methyltriethoxysilane (MTES), trimethylethoxysilane (TMES), trimethylsilanol (TMS), methyltrimethoxysilane (MTMS), dimethyldiethoxysilane (DMDEOS), ethyltriethoxysilane (ETES), and phenyltriethoxysilane (PTES), but is not limited thereto. Preferably, the above silica precursor composition may further comprise trimethylethoxysilane (TMES).

[0121] The heat resistance or flame retardancy of the silica insulation composite can be improved by including ammonium bicarbonate (NH4HCO3) or ammonium carbonate ((NH4)2CO3) particles in an amount, for example, of approximately 50 to 280 ppm, on the silica insulation composite or within the pores of the silica three-dimensional network structure (particularly, aerogel) during the preparation of the above silica insulation composite. To this end, ammonium ions (NH4 + A silicate containing ) in an amount of 0.1 to 2 weight% may be further added, and more specifically, ammonium ions (NH4) + Trimethylethoxysilane (TMES) containing ) in an amount of 0.1 to 2 weight% may be added, but is not limited thereto. Here, ammonium ions (NH4 + Trimethylethoxysilane (TMES) containing ) can be prepared by heating and refluxing hexamethyldisilazane (HMDS) at a temperature of approximately 100 to 140 °C for 10 minutes to 6 hours in the presence of an organic solvent and an acid catalyst, but is not limited thereto.

[0122] When the silica precursor composition includes a silicate containing the hydrophobic group, the silicate containing the hydrophobic group may be included in a molar ratio of 9:1 to 1:9 with the tetraalkyl silicate (molar ratio of silicate containing the hydrophobic group to tetraalkyl silicate). Within this range, the strength and thermal insulation performance of the aerogel can be improved.

[0123] In addition, the silica concentration of the silica precursor composition is 10 kg / m² 3 up to 100 kg / m² 3 , 20 kg / m 3 up to 80 kg / m² 3 , 30 kg / m 3 Up to 70 kg / m² 3 , 30 kg / m 3 up to 60 kg / m² 3 , or 35 kg / m² 3 Up to 45 kg / m 3 It may be, but is not limited thereto. The above silica concentration is the concentration of silica contained in the silica precursor relative to the silica precursor composition, and can be appropriately adjusted by varying the content of the silica precursor, organic solvent, and water.

[0124] The above silica precursor may be used in an amount such that the silica content contained in the silica sol is 0.1% by weight to 30% by weight, but is not limited thereto. If the silica content satisfies the above range, both the mechanical properties and the thermal insulation properties of the silica thermal insulation composite can be improved.

[0125] The above silica sol may include water and / or a polar organic solvent in the silica precursor composition.

[0126] When preparing the silica sol, the silica sol may be prepared by mixing the silica precursor composition and water in a molar ratio of 1:0.1 to 20, 1:1 to 10, or 1:2 to 10, but is not limited thereto.

[0127] In addition, the polar organic solvent may include alcohols, and specific examples include monohydric alcohols such as methanol, ethanol, isopropanol, butanol, etc.; polyhydric alcohols such as glycerol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, and sorbitol, etc.; or combinations thereof, but other solvents known to those skilled in the art may also be used without limitation. In the present invention, among these, the polar organic solvent may be a monohydric alcohol having 1 to 6 carbon atoms, such as methanol, ethanol, isopropanol, butanol, etc., such as ethanol, when considering miscibility with water and aerogel.

[0128] The above polar organic solvent can be used in an appropriate amount by a person skilled in the art, taking into account the degree of hydrophobization in the final silica insulation composite while promoting the surface modification reaction.

[0129] When preparing the above silica sol, the silica precursor composition and the organic solvent may be mixed in a weight ratio of 1:2 to 10, 1:2 to 8, or 1:2 to 6, but are not limited thereto.

[0130] The above silica precursor composition may further include an acid catalyst, specifically, when an alkoxysilane compound other than a hydrolysate is used as a precursor, the acid catalyst may further include an acid catalyst. In this case, any acid catalyst that lowers the pH to 3 or lower can be used without limitation, and examples include hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, oxalic acid, or acetic acid. In this case, the acid catalyst may be added in an amount that lowers the pH of the sol to 3 or lower, or it may be added in the form of an aqueous solution dissolved in an aqueous solvent.

[0131] The above catalyst composition may include an inorganic base such as sodium hydroxide or potassium hydroxide as a base catalyst; or an organic base such as ammonium hydroxide. Specific examples include sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), ammonia (NH3), ammonium hydroxide (NH4OH; ammonia solution), tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), methylamine, ethylamine, isopropylamine, monoisopropylamine, diethylamine, diisopropylamine, dibutylamine, trimethylamine, triethylamine, triisopropylamine, tributylamine, choline, monoethanolamine, diethanolamine, 2-aminoethanol, 2-(ethylamino)ethanol, 2-(methylamino)ethanol, N-methyl diethanolamine, dimethylaminoethanol, diethylaminoethanol, nitrilotriethanol, It may be 2-(2-aminoethoxy)ethanol, 1-amino-2-propanol, triethanolamine, monopropanolamine, dibutanolamine, pyridine, or a combination thereof, but is not limited thereto.

[0132] The above base catalyst may be included in an amount such that the pH of the sol becomes 7 to 11. If the pH of the sol falls outside this range, gelation may not be easy or the gelation rate may become excessively slow, potentially leading to reduced processability. Additionally, since the base may precipitate when added in a solid state, it may be preferable to add it in a solution diluted by an aqueous solvent or the aforementioned organic solvent. In this case, the dilution ratio of the base catalyst and the organic solvent, specifically the alcohol, may be 1:4 to 1:100 by volume, but is not limited thereto.

[0133] To prepare the silica sol, the silica precursor composition and the catalyst composition may be mixed in a volume ratio of 1:0.01 to 10.0, 1:0.01 to 5.0, or 1:0.01 to 2.0, but are not limited thereto.

[0134] In the present invention, the heat resistance and flame retardancy of the silica thermal insulation composite can be further improved by adding a mixture of CaMg3(CO3)4 (huntite) and hydromagnesite, plate-shaped Mg(OH)2, or a mixture thereof as an additive to the silica sol. The additive may be added in an amount of 0.1 to 10 parts by weight, 0.1 to 7 parts by weight, 0.5 to 7 parts by weight, or 0.5 to 5 parts by weight relative to the silica content of the silica network structure (particularly, aerogel), but is not limited thereto.

[0135] Additionally, additives may be added to the silica sol as needed. In this case, any known additives that can be added when manufacturing an aerogel may be used, and for example, additives such as opacifying agents may be used.

[0136] Gelation step of silica sol

[0137] In the present invention, silica sol can be impregnated into a substrate and then gelled.

[0138] The above impregnation process is a process that allows the catalytic silica sol to penetrate into the internal pores of the substrate. It can be performed by introducing the catalytic silica sol and the substrate into a reaction vessel, or by spraying the catalytic silica sol onto the substrate moving on a conveyor belt according to a roll-to-roll process. At this time, to improve the bonding between the substrate and the silica sol, the substrate can be lightly pressed to ensure sufficient impregnation. Subsequently, the material can be pressed to a certain thickness under a constant pressure to remove excess silica sol, thereby reducing the drying time.

[0139] The temperature of the silica sol in the reaction vessel may be 10 to 40 ℃, 20 to 40 ℃, 25 to 40 ℃, 30 to 40 ℃, or 35 to 45 ℃. It is preferable that the temperature of the silica sol in the reaction vessel satisfies the above range, as the aforementioned viscosity range of the catalyzed sol can be achieved more easily and the desired level of viscosity range can be satisfied even with a relatively short residence time.

[0140] The above-mentioned catalyzed silica sol can be impregnated into a substrate in a volume ratio of 0.1 to 10:1 (catalyzed silica sol:substrate), 0.1 to 1:1, 0.3 to 1:1, 0.5 to 1:1, or 0.7 to 1:1, but is not limited thereto.

[0141] The silica sol impregnated in the substrate can be gelled simultaneously with the impregnation process of the silica sol or sequentially after the impregnation process.

[0142] The substrate impregnated with the above-mentioned catalystd sol can be gelled on a moving element such as a conveyor belt.

[0143] The above "gelation" may refer to a sol-gel reaction, and the above "sol-gel reaction" may refer to forming a network structure from a silicon unit precursor material. Here, the network structure may refer to a planar net-like structure in which a specific polygon with one or more types of atomic arrangements is connected, or a structure that forms a three-dimensional skeletal structure by sharing vertices, edges, faces, etc. of a specific polyhedron.

[0144] The above gelation can be performed under an atmosphere temperature of 20 to 40 ℃, 25 to 35 ℃, or 30 to 35 ℃ to increase the strength of the pore structure.

[0145] The above gelation time is not specifically limited, but may be performed for, for example, 1 to 120 minutes, 1 to 100 minutes, 1 to 60 minutes, 5 to 60 minutes, 5 to 40 minutes, 10 to 40 minutes, 10 to 30 minutes, or 10 to 20 minutes.

[0146] Aging stage of the gelled wet gel complex

[0147] In the present invention, if necessary, an aging step may be further included to allow the wet gel composite obtained by gelation as described above to be left at an appropriate temperature so that chemical changes are completely completed. In the aging step, the network structure formed by gelation can be formed more firmly, thereby improving the mechanical stability of the silica thermal insulation composite.

[0148] The above aging step can be performed by leaving the gelled wet gel complex as is at an appropriate temperature, or by adding a cross-linking promoting compound.

[0149] During the above aging step, in the presence of the above wet gel composite, a solution of a base catalyst such as sodium hydroxide (NaOH), potassium hydroxide (KOH), ammonium hydroxide (NH4OH), triethylamine, or pyridine diluted in an organic solvent to a concentration of 1 to 10% may be added. In this case, Si-O-Si bonds are induced to the maximum extent within the silica network structure (e.g., aerogel), making the network structure of the silica gel more robust and facilitating the maintenance of the pore structure during the subsequent drying process. At this time, the organic solvent may be the aforementioned alcohol, and specifically, may include ethanol.

[0150] In addition, during the aging step, a mixed solution of an alkoxysilane compound and an alcohol can be added to provide not only unreacted sol but also an additional sol precursor source, thereby inducing additional gelation in the silica gel network structure and further strengthening the gel structure. At this time, the alkoxysilane compound may be included in an amount of 0.5 to 9.5 parts by weight, 1.0 to 9.5 parts by weight, or 1.5 to 9.5 parts by weight relative to 100 parts by weight of the total aging solution.

[0151] The above alkoxysilane compounds are tetramethyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), methyl triethyl orthosilicate, dimethyl diethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetrasecondary butyl orthosilicate, tetratertiary butyl orthosilicate, tetrahexyl orthosilicate, and tetracyclohexyl It may include one or more selected from the group consisting of tetracyclohexyl orthosilicate, tetradodecyl orthosilicate, methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES), trimethylethoxysilane (TMES), trimethylsilanol (TMS), trimethylchlorosilane (TMCS), ethyltriethoxysilane (ETES), dimethyldiethoxysilane (DMDEOS), and phenyltriethoxysilane.

[0152] In the present invention, to improve the flame retardancy or heat resistance of a silica insulation composite by partially including ammonium bicarbonate (NH4HCO3) or ammonium carbonate ((NH4)2CO3) particles on the finally manufactured silica insulation composite or in a silica three-dimensional network structure, for example, within the pores of an aerogel, an alkoxysilane compound to be added during aging is used, wherein ammonium ions (NH4 + It is preferable to use trimethylethoxysilane (TMES) containing ) in an amount of 0.1 to 2 weight%, but is not limited thereto.

[0153] In addition, the above alcohol may specifically be a monohydric alcohol such as methanol, ethanol, isopropanol, butanol, etc.; or a polyhydric alcohol such as glycerol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, and sorbitol, etc., and preferably may be a monohydric alcohol having 1 to 6 carbon atoms such as methanol, ethanol, isopropanol, butanol, etc., e.g. ethanol, but is not limited thereto.

[0154] The above aging step can be performed by leaving the product at a temperature of 30°C to 80°C, 40°C to 80°C, or 50°C to 80°C for 0.1 to 20 hours, 0.5 to 15 hours, 0.5 to 10 hours, 0.5 to 7 hours, or 1 to 5 hours to strengthen the pore structure, and within this range, it is possible to prevent a decrease in productivity while preventing the loss of solvent due to evaporation, thereby preventing an increase in production costs.

[0155] In addition, the above aging step may be performed by first aging at 30°C to 80°C for 0.1 to 5 hours to strengthen the pore structure, and then by adding a solution in which the above-mentioned base catalyst is diluted in an organic solvent, and second aging may be performed at 30°C to 80°C for 0.1 to 20 hours, 0.5 to 15 hours, 0.5 to 10 hours, 0.5 to 7 hours, or 1 to 5 hours.

[0156] In addition, the above aging step may be performed first as described above to strengthen the pore structure as well as to hydrophobize the pores, and then a mixed solution of an alkoxysilane compound and an alcohol may be added to perform a second aging step at 30°C to 80°C for 0.1 to 20 hours, 0.5 to 15 hours, 0.5 to 10 hours, 0.5 to 7 hours, or 1 to 5 hours.

[0157] The above aging step may be performed in a separate reaction vessel after recovering the gelled wet gel complex, or it may be performed inside the reaction vessel where the gelling step was performed.

[0158] Surface modification step of aged wet gel complex

[0159] The present invention includes a surface modification step of hydrophobizing the surface of a wet gel complex obtained by gelation as described above or an aged wet gel complex in the presence of a surface modifier.

[0160] The above surface modifier may be any compound that hydrophobicizes the wet gel surface without limitation, such as a silane compound, a siloxane compound, a silanol compound, a silazane compound, or a combination thereof. Specific examples include silane compounds comprising trimethylchlorosilane (TMCS), dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES), trimethylethoxysilane (TMES), vinyltrimethoxysilane, ethyltriethoxysilane, phenyltriethoxysilane, phenyltrimethoxysilane, tetraethoxysilane, dimethyldichlorosilane, 3-aminopropyltriethoxysilane, etc.; siloxane compounds comprising polydimethylsiloxane (PDMS), polydiethylsiloxane, or octamethylcyclotetrasiloxane, etc. Silanol-based compounds including trimethylsilanol, triethylsilanol, triphenylsilanol, and t-butyldimethylsilanol, etc.; silazane-based compounds including 1,2-diethyldisilazane, 1,1,2,2-tetramethyldisilazane, 1,1,3,3-tetramethyldisilazane, 1,1,1,2,2,2-hexamethyldisilazane (HMDS), 1,1,2,2-tetraethyldisilazane, or 1,2-diisopropyldisilazane, etc.; or a combination thereof, but not limited thereto.

[0161] In the present invention, to improve the flame retardancy or heat resistance of a silica thermal insulation composite by partially including ammonium bicarbonate (NH4HCO3) or ammonium carbonate ((NH4)2CO3) particles on the finally manufactured silica thermal insulation composite or within the pores of a silica three-dimensional network structure (e.g., aerogel), ammonium ions (NH4) are used as a surface modifier. + It is preferable to use trimethylethoxysilane (TMES) containing ) in an amount of 0.1 to 2 weight%, but is not limited thereto. The surface modifier may be used as a solution diluted in an organic solvent. Here, the organic solvent may be an alcohol (organic solvent), and the surface modifier may be diluted to 1 to 15 volume%, 1 to 10 volume%, or 1 to 5 volume% based on the total volume of the diluted solution.

[0162] In addition, the surface modifier may be added in an amount of 0.01 to 95 volume%, 0.1 to 90 volume%, 1 to 90 volume%, 10 to 90 volume%, 50 to 90 volume%, or 70 to 90 volume% with respect to the wet gel composite for a sufficient surface modification effect, but is not limited thereto.

[0163] During the above surface modification step, ammonium ions (NH4 + In addition to using a surface modifier containing ), ammonia water may be further added so that ammonium bicarbonate (NH4HCO3) or ammonium carbonate ((NH4)2CO3) particles are included in the above-mentioned amount on the final prepared silica insulation composite or within the pores of the silica three-dimensional network structure (e.g., aerogel), or so that when the silica insulation composite is heated at a temperature of 150°C for 60 minutes, ammonia gas is generated in the above-mentioned amount per unit weight of the silica insulation composite.

[0164] The surface modification step may be performed for 1 to 24 hours, 2 to 12 hours, or 4 to 12 hours at a temperature of 50 to 90 ℃ or 50 to 80 ℃, but is not limited thereto.

[0165] drying stage

[0166] The present invention may include a drying step of drying a surface-modified wet gel composite to obtain a silica thermal insulation composite.

[0167] The above drying is performed as a process that removes only the solvent while maintaining the pore structure of the aged gel, and can be performed, for example, by supercritical drying or atmospheric pressure drying.

[0168] The above supercritical drying process is performed using supercritical carbon dioxide. For example, a matured wet gel complex is placed into a supercritical drying reactor, and then liquid CO2 is filled and a solvent exchange process is performed to replace the alcohol solvent inside the wet gel with CO2. Afterward, the temperature is raised to 40 to 70 ℃ at a constant heating rate, e.g., 0.1 ℃ / min to 1 ℃ / min. Subsequently, a pressure greater than the pressure at which carbon dioxide reaches a supercritical state, e.g. 100 bar to 150 bar, is maintained to maintain the carbon dioxide in a supercritical state for a certain period of time, specifically 20 minutes to 1 hour. Generally, carbon dioxide reaches a supercritical state at a temperature of 31 ℃ and a pressure of 73.8 bar. A silica insulation composite can be manufactured by maintaining the carbon dioxide at a constant temperature and constant pressure for 2 to 12 hours, more specifically 2 to 6 hours, and then gradually removing the pressure to complete the supercritical drying process, but is not limited thereto.

[0169] The above process may not include a process of lowering the pressure of the extract discharged from the supercritical extractor used during supercritical drying to a range of 45 to 50 bar, thereby lowering the temperature of the extract to a temperature of 30°C or lower to induce the precipitation of ammonium carbonate or ammonium hydrocarbon.

[0170] In addition, the atmospheric pressure drying process may be carried out according to conventional methods such as hot air drying or IR drying at a temperature of 70 to 200 ℃ and atmospheric pressure (1±0.3 atm), but is not limited thereto.

[0171] In the present invention, once a silica insulation composite, for example an aerogel composite, is prepared as described above, the process may include a step of encapsulating the front surface of the silica insulation composite by surrounding it with a film. An example of the encapsulation process is that a film having an adhesive layer or a film formed on one side is cut into a shape corresponding to the outer surface of the silica insulation composite, and then the film is adhered to the surface of the silica insulation composite, particularly the top and bottom surfaces, through the adhesive layer or the film (Fig. 1). As another example, a single film is prepared and then wrapped around the top, side, bottom, and side surfaces of the silica insulation composite along the width direction (Direction A). Additionally, another film is prepared and then wrapped around the top, side, bottom, and side surfaces of the silica insulation composite along the length direction (Direction B). At this time, the film may be prepared by cutting it to a shape and size corresponding to the surface so as to surround all the above surfaces (Figs. 2a, 2b, 2c). As another example, a single film may be prepared, a silica insulation composite may be placed on the film, and the film may be folded. If necessary, the film may be cut to the size of the silica insulation composite, and then the outer surface of the film may be sealed by heat-fusing it along the outer edge of the silica insulation composite or by sealing it using an adhesive or other methods (Fig. 3). As another example, two films may be prepared, a silica insulation composite may be interposed between the two films, and then the film and the silica insulation composite may be fused by heat-fusing, or the two layers of film may be sealed by sealing them along the outer surface of the silica insulation composite. As yet another example, a silica insulation composite may be placed in the center of the cut film, and then the film may be folded according to the shape of the silica insulation composite so that the front surface of the silica insulation composite is completely covered, and the edges of the two overlapping films may be sealed on one side of the silica insulation composite (Fig. 4).

[0172]

[0173] According to another embodiment of the present invention, the invention relates to a battery module or battery pack comprising an insulating member according to the present invention.

[0174] The above battery module may include a module case having an internal space and one or more battery cells existing within the internal space.

[0175] The number of battery cells accommodated in the module case is not limited and can be adjusted according to the application of the battery module. The battery cells accommodated in the module case may be electrically connected to one another. The type of battery cell accommodated in the module case is not limited, but, for example, the battery module may include cylindrical, prismatic, or pouch-type case battery cells.

[0176] The battery module may include an insulating member according to the present disclosure within the module case of the battery module. The insulating member may be located between battery cells accommodated within the module case. The insulating member may be positioned between the module case and a plurality of battery cells, i.e., around the module case. A silica insulating composite located within the module case acts as an insulator to reduce heat propagation within the battery module and improve the safety of the battery module.

[0177] The battery pack may include one or more of the battery modules. In the battery pack, the battery modules may be electrically connected to each other. The battery pack may include an insulating member according to the present disclosure. For example, the insulating member may be located between the battery modules of the battery pack. The insulating member may also at least partially surround a plurality of battery modules within the battery pack. The insulating member may act as an insulating material within the battery pack to reduce heat propagation and improve the safety of the battery pack.

[0178] The present invention is not limited thereto, but may include the following embodiments as examples within the scope of the present invention:

[0179] 1. A silica thermal insulation composite comprising a substrate and a plurality of silica particles and a silica network structure comprising one or more pores; and a thermal insulation member comprising a film surrounding the silica thermal insulation composite, wherein when heat of 700°C is applied to a first surface of the thermal insulation member, the 180°C heat resistance index (A) represented by the following Formula 1 is 50% or more:

[0180] [Equation 1]

[0181]

[0182] In the above Equation 1, the time to reach 180°C (seconds) of the insulating member refers to the time (seconds) when the temperature of the second surface of the insulating member reaches 180°C, and the time to reach 180°C (seconds) of the silica insulating composite refers to the time (seconds) when the temperature of the second surface of the silica insulating composite reaches 180°C when heat of 700°C is applied to the first surface of the silica insulating composite that is not surrounded by a film.

[0183] 2. In the first embodiment, the time (seconds) required for the temperature of the second surface of the insulating member to reach 180°C may be 15 seconds or more.

[0184] 3. In at least one of the first and second embodiments, when heat of 700 ℃ is applied to the first surface of the insulating member, the 350 ℃ heat resistance index (B) represented by the following Formula 2 may be 50% or more:

[0185] [Equation 2]

[0186]

[0187] In the above Equation 2, the time (seconds) to reach 350 ℃ of the insulating member refers to the time (seconds) for the temperature of the second surface of the insulating member to reach 350 ℃, and the time (seconds) to reach 350 ℃ of the silica insulating composite refers to the time (seconds) for the temperature of the second surface of the silica insulating composite to reach 350 ℃ when heat of 700 ℃ is applied to the first surface of the silica insulating composite that is not surrounded by a film.

[0188] 4. In at least one of the first to third embodiments, the time (seconds) required for the temperature of the second surface of the insulating member to reach 350°C may be 100 seconds or more.

[0189] 5. In at least one of the first to fourth embodiments, the film may have a heat generation amount of 1,500 to 3,000 J / g.

[0190] 6. In at least one of the first to fifth embodiments, the thickness of the silica thermal insulation composite may be 0.5 to 10 mm.

[0191] 7. In at least one of the first to sixth embodiments, the silica network structure may comprise silica, methylsilylated silica, dimethylsilylated silica, trimethylsilylated silica, or a mixture thereof.

[0192] 8. In at least one of the first to seventh embodiments, the silica thermal insulation composite may comprise particles in which a plurality of silica particles having a particle size greater than 0 and less than or equal to 5 nm are aggregated or bonded.

[0193] 9. In the eighth embodiment, the average particle size of the aggregated or combined particles may be 5 to 2,000 nm.

[0194] 10. In at least one of the first to ninth embodiments, the density of the silica thermal insulation composite is 0.05 to 0.50 g / cm³ 3 It could be.

[0195] 11. In at least one of the first to ten embodiments, the silica network structure may include silica aerogel or be silica aerogel.

[0196] 12. In at least one of the first to eleventh embodiments, the silica thermal insulation composite may be an aerogel composite comprising a substrate and a silica aerogel having a plurality of open pores formed therein.

[0197] 13. In at least one of the first to twelfth embodiments, the insulating member may be in the shape of a sheet.

[0198] 14. The invention relates to a battery module comprising: one or more battery cells in an internal space; and at least one insulating member of the first to thirteenth embodiments.

[0199] 15. The invention relates to a battery pack comprising a battery module comprising one or more battery cells in an internal space; and at least one insulating member of the first to thirteenth embodiments.

[0200] The present invention will be explained in detail below through the following examples. However, the following examples are merely illustrative of the present invention, and the scope of the present invention is not limited by the following examples.

[0201]

[0202] Examples

[0203]

[0204] [Preparation Example 1] Preparation of a silica thermal insulation composite

[0205] 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were added and mixed, and 0.62 mol of hexamethyldisilazane (HMDS) was added and mixed. Subsequently, the mixture was refluxed at 100 °C for 1 hour to confirm the generation of ammonia (NH3) gas. Through the above process, ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.85 wt% was prepared. A silica precursor composition was prepared by mixing the obtained trimethylethoxysilane (TMES) and tetraethyl orthosilicate (TEOS) in a molar ratio of 1:9. A silica sol was prepared by mixing the silica precursor composition with water in a molar ratio of 1:10 and adding ethanol in a weight ratio of 1:2 with the silica precursor composition. Hydrochloric acid was added to the silica sol so that the pH of the silica sol was 3 or lower to promote hydrolysis. Plate-shaped powder Mg(OH)2 was added to the silica sol prepared as above in an amount equal to 2 wt parts of the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol was added to prepare a catalyzed sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the fiber with the silica sol, ensuring that the silica sol impregnated the fiber mat in a 1:1 volume ratio (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. After gelation was complete, the wet gel complex was stabilized at room temperature (25 °C) for 10 minutes, followed by primary aging in a 70 °C oven for 30 minutes. A solution of 2.9 wt% methyltriethoxysilane (MTES) diluted in ethanol with a moisture content of 10 wt% was prepared and added to the primary aged wet gel complex at 109% of the volume of the wet gel complex, followed by secondary aging in a 75 °C oven for 2 hours. A hexamethyldisilazane (HMDS) / ethanol solution (5:95 volume ratio) was added as a surface modification solution at 90 volume% of the volume of the wet gel complex, followed by surface modification at 75 °C for 4 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected.Subsequently, the temperature inside the extractor was raised to 70°C over a period of 1 hour and 20 minutes. Upon reaching 70°C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Subsequently, CO2 was vented over a period of 2 hours to produce a hydrophobic silica aerogel composite.

[0206]

[0207] [Preparation Example 2] Preparation of a silica thermal insulation composite

[0208] A silica precursor solution was prepared by mixing tetraethyl orthosilicate (TEOS) and water in a molar ratio of 1:4 and adding ethanol in a weight ratio of 1:1 with TEOS. To promote the hydrolysis of the silica precursor solution, an acid was added to lower the pH of the silica precursor solution to 3 or lower, and the mixture was stirred for at least 2 hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a weight ratio of 1:6 with the hydrated TEOS solution. Hydrochloric acid was added to lower the pH of the silica sol to 3 or lower to promote hydrolysis. To the silica sol prepared as above, Ultracarb (LKAB), a mixture of CaMg3(CO3)4 (huntite) and hydromagnesite, was added in an amount equal to 0.2 parts by weight of the silica concentration. A catalytic sol was prepared by adding a base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the fiber with the silica sol, ensuring that the silica sol impregnated the fiber mat in a 1:1 volume ratio (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. After gelation was complete, the wet gel complex was stabilized at room temperature (25 ℃) for 10 minutes, followed by primary aging in a 70 ℃ oven for 30 minutes. A solution of 2.9 wt% methyltriethoxysilane (MTES) diluted in ethanol with a moisture content of 10 wt% was prepared and added to the primary aged wet gel complex at 109% by volume, followed by secondary aging in a 75 ℃ oven for 2 hours. To prepare the surface modifier, 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were added and mixed, and 0.62 mol of hexamethyldisilazane (HMDS) was added and mixed. Subsequently, the mixture was refluxed at 100 °C for 3 hours to remove ammonium ions (NH4. + Trimethylethoxysilane (TMES) containing 0.62 wt% was prepared. A solution (10 vol%) of the above trimethylethoxysilane (TMES) diluted in ethanol was added at 90 vol% based on the volume of the wet gel composite, and surface modification was performed at a temperature of 75 °C for 6 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Subsequently, the temperature inside the extractor was raised to 70 °C over 1 hour and 20 minutes. Upon reaching 70 °C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Afterward, CO2 was vented over a period of 2 hours to produce a hydrophobic silica aerogel composite.

[0209]

[0210] [Preparation Example 3] Preparation of a silica thermal insulation composite

[0211] A silica precursor solution was prepared by mixing tetraethyl orthosilicate (TEOS) and water in a molar ratio of 1:4 and adding ethanol in a weight ratio of 1:1 with TEOS. To promote the hydrolysis of the silica precursor solution, an acid was added to lower the pH of the silica precursor solution to 3 or lower, and the mixture was stirred for at least 2 hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a weight ratio of 1:6 with the hydrated TEOS solution. Hydrochloric acid was added to lower the pH of the silica sol to 3 or lower to promote hydrolysis. Plate-shaped powder Mg(OH)2 was added to the silica sol prepared as described above in an amount of 1.5 parts by weight relative to the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 was added to the silica sol to prepare a catalyzed sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the fiber with the silica sol, ensuring that the silica sol impregnated the fiber mat in a 1:1 volume ratio (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. After gelation was complete, the wet gel complex was stabilized at room temperature (25 °C) for 10 minutes, followed by primary aging in a 70 °C oven for 30 minutes. To the primary aged wet gel complex, a solution of 2.9 wt% methyltriethoxysilane (MTES) diluted in ethanol with a water content of 10 wt% was prepared and added at 109% by volume of the wet gel complex, followed by secondary aging in a 75 °C oven for 2 hours. To prepare the surface modifier, 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were added and mixed, and 0.62 mol of hexamethyldisilazane (HMDS) was added and mixed. Subsequently, the mixture was refluxed at 100 °C for 4 hours to [induce] ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.51 wt% was prepared. A solution (5 vol%) of the trimethylethoxysilane (TMES) diluted in ethanol was added at 90 vol% based on the volume of the wet gel complex, and then 300 ppm of NH4 relative to the weight of the trimethylethoxysilane (TMES) was added. + Water ammonia was added to add ions. Subsequently, surface modification was performed at a temperature of 75 °C for 4 hours. A wet silica gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Then, the temperature inside the extractor was raised to 70 °C over 1 hour and 20 minutes. Upon reaching 70 °C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, followed by stopping the CO2 injection for 20 minutes; this process was repeated 4 times. Ethanol was recovered through the bottom of the separator during the CO2 injection and discharge. Afterward, CO2 was vented over a period of 2 hours to prepare a hydrophobic silica aerogel composite.

[0212]

[0213] [Preparation Example 4] Preparation of a silica thermal insulation composite

[0214] A silica precursor solution was prepared by mixing tetraethyl orthosilicate (TEOS) and water in a molar ratio of 1:4 and adding ethanol in a weight ratio of 1:1 with TEOS. To promote the hydrolysis of the silica precursor solution, an acid was added to lower the pH of the silica precursor solution to 3 or lower, and the mixture was stirred for at least 2 hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a weight ratio of 1:6 with the hydrated TEOS solution. Hydrochloric acid was added to lower the pH of the silica sol to 3 or lower to promote hydrolysis. Plate-shaped powder Mg(OH)2 was added to the silica sol prepared as described above in an amount of 5 parts by weight relative to the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 was added to the silica sol to prepare a catalyzed sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through it as a substrate to infiltrate the fiber with the silica sol, ensuring that the silica sol impregnated the fiber mat at a 1:1 volume ratio (silica sol:fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. As an aging and surface modifier, 1.30 mol of ethanol and 0.02 g of the acid catalyst HCl were mixed, along with 0.62 mol of hexamethyldisilazane (HMDS), and the mixture was refluxed at 100 ℃ for 1 hour to [induce] ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.85 wt% was prepared. A solution (2.4 wt%) of the above trimethylethoxysilane (TMES) diluted in ethanol was added at 109 volume% based on the volume of the wet gel composite, and aging was carried out at a temperature of 75 ℃ for 1 hour. Subsequently, a solution (10 volume%) of the prepared trimethylethoxysilane (TMES) diluted in ethanol was added at 90 volume% based on the volume of the aged wet gel composite, and surface modification was performed at a temperature of 75 ℃ for 8 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Subsequently, the temperature inside the extractor was raised to 70°C over a period of 1 hour and 20 minutes. Upon reaching 70°C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Subsequently, CO2 was vented over a period of 2 hours to produce a hydrophobic silica aerogel composite.

[0215]

[0216] [Preparation Example 5] Preparation of a silica thermal insulation composite

[0217] 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were mixed, followed by the addition of 0.62 mol of hexamethyldisilazane (HMDS), and the mixture was refluxed at 100 °C for 3 hours to produce ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.62 wt% was prepared. A silica precursor composition was prepared by mixing the obtained trimethylethoxysilane (TMES) and tetraethyl orthosilicate (TEOS) in a molar ratio of 1:9. A silica sol was prepared by mixing the silica precursor composition with water in a molar ratio of 1:10 and adding ethanol in a weight ratio of 1:2 with the silica precursor composition. Hydrochloric acid was added to the silica sol so that the pH of the silica sol was 3 or lower to promote hydrolysis. Ultracarb (LKAB), a mixture of CaMg3(CO3)4 (huntite) and hydromagnesite, was added to the silica sol prepared as above in an amount equal to 0.2 wt parts of the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol was added to prepare a catalyzed sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the silica sol into the fiber, ensuring that the silica sol was impregnated into the fiber mat at a volume ratio of 1:1 (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. A solution (2.4 wt%) of the prepared trimethylethoxysilane (TMES) diluted in ethanol was added at 109 volume% based on the volume of the wet gel composite, and the mixture was aged at a temperature of 75 ℃ for 1 hour. A hexamethyldisilazane (HMDS) / ethanol solution (5:95 volume ratio) was added to the aged wet gel composite at 90 volume% based on the volume of the wet gel composite as a surface modification solution, and surface modification was performed at a temperature of 75 °C for 4 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected.Subsequently, the temperature inside the extractor was raised to 70°C over a period of 1 hour and 20 minutes. Upon reaching 70°C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Subsequently, CO2 was vented over a period of 2 hours to produce a hydrophobic silica aerogel composite.

[0218]

[0219] [Preparation Example 6] Preparation of a silica thermal insulation composite

[0220] 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were mixed, followed by the addition of 0.62 mol of hexamethyldisilazane (HMDS), and the mixture was refluxed at 100 °C for 4 hours to produce ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.51 wt% was prepared. A silica precursor composition was prepared by mixing the obtained trimethylethoxysilane (TMES) and tetraethyl orthosilicate (TEOS) in a molar ratio of 0.5:9.5. A silica sol was prepared by mixing the silica precursor composition with water in a molar ratio of 1:10 and adding ethanol in a weight ratio of 1:2 with the silica precursor composition. Hydrochloric acid was added to the silica sol so that the pH of the silica sol was 3 or lower to promote hydrolysis. Ultracarb (LKAB), a mixture of CaMg3(CO3)4 (huntite) and hydromagnesite, was added to the silica sol prepared as above in an amount equal to 0.5 wt parts of the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol was added to prepare a catalyzed sol. After filling an impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the silica sol into the fiber, ensuring that the silica sol was impregnated into the fiber mat at a volume ratio of 1:1 (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. After gelation was complete, the wet gel composite was stabilized at room temperature (25 ℃) for 10 minutes, followed by primary aging in a 70 ℃ oven for 30 minutes. A solution of 2.9 wt% methyltriethoxysilane (MTES) diluted in ethanol with a moisture content of 10 wt% was prepared and added to the primary aged wet gel composite at 109% of the volume of the wet gel composite, followed by secondary aging in a 75 ℃ oven for 2 hours.Subsequently, as a surface modification solution, a solution (10 vol%) of the prepared trimethylethoxysilane (TMES) diluted in ethanol was added at 90 vol% based on the volume of the aged wet gel composite, and surface modification was performed at a temperature of 75 ℃ for 4 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Then, the temperature inside the extractor was raised to 70 ℃ over 1 hour and 20 minutes. Upon reaching 70 ℃ and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Subsequently, CO2 was vented over a period of 2 hours to prepare a hydrophobic silica aerogel composite.

[0221]

[0222] [Preparation Example 7] Preparation of a silica thermal insulation composite

[0223] 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were mixed, followed by the addition of 0.62 mol of hexamethyldisilazane (HMDS), and the mixture was refluxed at 100 °C for 3 hours to produce ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.62 wt% was prepared. A silica precursor composition was prepared by mixing the obtained trimethylethoxysilane (TMES) and tetraethyl orthosilicate (TEOS) in a molar ratio of 0.5:9.5. A silica sol was prepared by mixing the silica precursor composition with water in a molar ratio of 1:10 and adding ethanol in a weight ratio of 1:2 with the silica precursor composition. Hydrochloric acid was added to the silica sol so that the pH of the silica sol was 3 or lower to promote hydrolysis. Plate-shaped powder Mg(OH)2 was added to the silica sol prepared as above in an amount of 3 parts by weight relative to the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol was added to prepare a catalyzed sol. After filling an impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the silica sol into the fiber, ensuring that the silica sol was impregnated into the fiber mat at a volume ratio of 1:1 (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 30 ℃. After gelation was complete, the wet gel composite was stabilized at room temperature (25 ℃) for 10 minutes, followed by primary aging in a 70 ℃ oven for 30 minutes. A solution of 2.9 wt% methyltriethoxysilane (MTES) diluted in ethanol with a moisture content of 10 wt% was prepared and added to the primary aged wet gel composite at 109% of the volume of the wet gel composite, followed by secondary aging in a 75 ℃ oven for 2 hours. Subsequently, as a surface modification solution, a solution (5 vol%) of the trimethylethoxysilane (TMES) diluted in ethanol was added at 90 vol% based on the volume of the wet gel complex, and then 500 ppm of NH4 relative to the weight of the trimethylethoxysilane (TMES) +Water ammonia was added to add ions. Subsequently, surface modification was performed at a temperature of 75 °C for 4 hours. A wet silica gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Then, the temperature inside the extractor was raised to 70 °C over 1 hour and 20 minutes. Upon reaching 70 °C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, followed by stopping the CO2 injection for 20 minutes; this process was repeated 4 times. Ethanol was recovered through the bottom of the separator during the CO2 injection and discharge. Afterward, CO2 was vented over a period of 2 hours to prepare a hydrophobic silica aerogel composite.

[0224]

[0225] [Comparative Preparation Example 1] Preparation of a silica thermal insulation composite

[0226] A silica precursor solution was prepared by mixing tetraethyl orthosilicate (TEOS) and water in a molar ratio of 1:4 and adding ethanol in a weight ratio of 1:1 with TEOS. To promote the hydrolysis of the silica precursor solution, an acid was added to lower the pH of the silica precursor solution to 3 or lower, and the mixture was stirred for at least 2 hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a weight ratio of 1:6 with the hydrated TEOS solution. Hydrochloric acid was added to lower the pH of the silica sol to 3 or lower to promote hydrolysis. A catalyzed sol was prepared by adding a base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the silica sol into the fiber, ensuring that the silica sol was impregnated into the fiber mat at a volume ratio of 1:1 (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 25 ℃. After gelation was complete, a solution of 2.4 wt% ammonia water (NH4OH) diluted in ethanol with a moisture content of 10 wt% was added to the wet gel complex at 109% of the volume of the wet gel blanket as an aging solution, and the mixture was aged at a temperature of 75 ℃ for 1 hour. To prepare a surface modifier, 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were added and mixed, and 0.62 mol of hexamethyldisilazane (HMDS) was added and mixed. Subsequently, the mixture was refluxed at 100 °C for 4 hours to [induce] ammonium ions (NH4 +Trimethylethoxysilane (TMES) containing 0.51 wt% was prepared. A solution (10 wt%) of the above trimethylethoxysilane (TMES) diluted in ethanol was added at 90 wt% based on the volume of the wet gel composite, and surface modification was performed at a temperature of 75 °C for 4 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Subsequently, the temperature inside the extractor was raised to 70 °C over 1 hour and 20 minutes. Upon reaching 70 °C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Afterward, CO2 was vented over a period of 2 hours to produce a hydrophobic silica aerogel composite.

[0227]

[0228] [Comparative Preparation Example 2] Preparation of a silica thermal insulation composite

[0229] A silica precursor solution was prepared by mixing tetraethyl orthosilicate (TEOS) and water in a molar ratio of 1:4 and adding ethanol in a weight ratio of 1:1 with TEOS. To promote the hydrolysis of the silica precursor solution, an acid was added to lower the pH of the silica precursor solution to 3 or lower, and the mixture was stirred for at least 2 hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a weight ratio of 1:6 with the hydrated TEOS solution. Hydrochloric acid was added to lower the pH of the silica sol to 3 or lower to promote hydrolysis. Plate-shaped powder Mg(OH)2 was added to the silica sol prepared as described above in an amount of 2.5 parts by weight relative to the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 was added to the silica sol to prepare a catalyzed sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the silica sol into the fiber, ensuring that the silica sol was impregnated into the fiber mat at a volume ratio of 1:1 (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 25 ℃. After gelation was complete, a solution of 2.4 wt% ammonia water (NH4OH) diluted in ethanol with a moisture content of 10 wt% was added to the wet gel complex at 109% of the volume of the wet gel blanket as an aging solution, and the mixture was aged at a temperature of 75 ℃ for 1 hour. A hexamethyldisilazane (HMDS) / ethanol solution (5:95 volume ratio) was added to the aged wet gel composite at 90 volume% based on the volume of the wet gel composite as a surface modification solution, and surface modification was performed at a temperature of 75 °C for 4 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected.Subsequently, the temperature inside the extractor was raised to 70°C over a period of 1 hour and 20 minutes. Upon reaching 70°C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Subsequently, CO2 was vented over a period of 2 hours to produce a hydrophobic silica aerogel composite.

[0230]

[0231] [Comparative Preparation Example 3] Preparation of a silica thermal insulation composite

[0232] A silica precursor composition was prepared by mixing trimethylethoxysilane (TMES) and tetraethyl orthosilicate (TEOS) in a molar ratio of 1:9. A silica sol was prepared by mixing the silica precursor composition with water in a molar ratio of 1:10 and adding ethanol in a weight ratio of 1:2 with the silica precursor composition. Hydrochloric acid was added to the silica sol to lower the pH to 3 or lower in order to promote hydrolysis. Ultracarb (LKAB), a mixture of CaMg3(CO3)4 (huntite) and hydromagnesite, was added to the silica sol prepared as above in an amount equal to 0.2 parts by weight of the silica concentration. A base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 was added to the silica sol to prepare a catalyzed sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the silica sol into the fiber, ensuring that the silica sol impregnated the fiber mat at a 1:1 volume ratio (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 25 ℃. A hexamethyldisilazane (HMDS) / ethanol solution (5:95 volume ratio) was added as a surface modification solution to the gelled wet gel composite at 90 vol% based on the volume of the wet gel composite, and surface modification was performed at a temperature of 75 ℃ for 4 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Subsequently, the temperature inside the extractor was raised to 70°C over 1 hour and 20 minutes, and when 70°C and 150 bar were reached, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge.Subsequently, a hydrophobic silica aerogel composite was prepared by venting CO2 over a period of 2 hours.

[0233]

[0234] [Comparative Preparation Example 4] Preparation of a silica thermal insulation composite

[0235] A silica precursor solution was prepared by mixing tetraethyl orthosilicate (TEOS) and water in a molar ratio of 1:4 and adding ethanol in a weight ratio of 1:1 with TEOS. To promote the hydrolysis of the silica precursor solution, an acid was added to lower the pH of the silica precursor solution to 3 or lower, and the mixture was stirred for at least 2 hours to prepare a hydrated TEOS solution. A silica sol was prepared by adding ethanol in a weight ratio of 1:6 with the hydrated TEOS solution. Hydrochloric acid was added to lower the pH of the silica sol to 3 or lower to promote hydrolysis. A catalyzed sol was prepared by adding a base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol. After filling the impregnation tank with 33.3 L of catalyzed silica sol, a fiber (basalt fiber mat, 2 mm) was passed through as a substrate to infiltrate the fiber with the silica sol, ensuring that the silica sol was impregnated into the fiber mat at a volume ratio of 1:1 (silica sol: fiber). The fiber, infiltrated with silica sol after passing through the impregnation tank, was gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 25 ℃. After gelation was complete, a solution of 2.9 wt% methyltriethoxysilane (MTES) diluted in ethanol with a moisture content of 10 wt% was added to the wet gel complex as an aging solution, and the mixture was aged at a temperature of 75 ℃ for 1 hour. As a surface modification solution, a solution of trimethylethoxysilane (TMES) diluted in ethanol (10 vol%) was added at 90 vol% based on the volume of the aged wet gel composite, and surface modification was performed at a temperature of 75 ℃ for 12 hours. A silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Subsequently, the temperature inside the extractor was raised to 70 ℃ over 1 hour and 20 minutes, and when 70 ℃ and 150 bar were reached, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times.Ethanol was recovered through the bottom of the separator during CO2 injection and exhaust. Subsequently, a hydrophobic silica aerogel composite was prepared by venting CO2 over a period of 2 hours.

[0236]

[0237] [Comparative Preparation Example 5] Preparation of a silica thermal insulation composite

[0238] 1.30 mol of ethanol and 0.02 g of acid catalyst HCl were mixed, followed by the addition of 0.62 mol of hexamethyldisilazane (HMDS), and the mixture was refluxed at 100 °C for 6 hours to produce ammonium ions (NH4 + Trimethylethoxysilane (TMES) containing 0.48 wt% was prepared. A silica precursor composition was prepared by mixing the obtained trimethylethoxysilane (TMES) and tetraethyl orthosilicate (TEOS) in a molar ratio of 1:9. A silica sol was prepared by mixing the silica precursor composition with water in a molar ratio of 1:10 and adding ethanol in a weight ratio of 1:2 with the silica precursor composition. Hydrochloric acid was added to ensure the pH of the silica sol was 3 or lower to promote hydrolysis. A catalytic sol was prepared by adding a base catalyst solution (5 wt% NaOH aqueous solution) in a volume ratio of 99:1 with the silica sol. After filling 33.3 L of the catalytic silica sol into an impregnation tank, the silica sol was infiltrated into the fibers by passing the sol through a fiber (basalt fiber mat, 2 mm) as a substrate, such that the silica sol impregnated the fiber mat in a volume ratio of 1:1 (silica sol: fiber). The fibers, infiltrated with silica sol after passing through the impregnation tank, were gelled while moving along a conveyor belt at a constant speed. During this process, the ambient temperature on the conveyor belt was maintained at 25 ℃. After gelation was complete, the fibers were stabilized at room temperature (25 ℃) for 10 minutes, followed by aging in a 70 ℃ oven for 30 minutes. Subsequently, ammonium ions (NH4 +A solution (10 vol%) of trimethylethoxysilane (TMES) not containing ) diluted in ethanol was added at 90 vol% based on the volume of the aged wet gel composite, and surface modification was performed at a temperature of 75 °C for 2 hours. The silica wet gel was placed in a 7.2 L supercritical extractor, and CO2 was injected. Subsequently, the temperature inside the extractor was raised to 70 °C over 1 hour and 20 minutes. Upon reaching 70 °C and 150 bar, CO2 was injected and discharged at a rate of 0.5 L / min for 20 minutes, and the process of stopping CO2 injection and maintaining the state for 20 minutes was repeated 4 times. Ethanol was recovered through the bottom of the separator during CO2 injection and discharge. Afterward, CO2 was vented over a period of 2 hours to prepare a hydrophobic silica aerogel composite.

[0239]

[0240] [Examples 1 to 7 and Comparative Examples 1 to 5] Manufacture of thermal insulation members

[0241] Specimens were prepared such that the width and length of the silica insulation composites prepared in Manufacturing Examples 1 to 7 and Comparative Manufacturing Examples 1 to 5 were approximately 75 mm x 75 mm. As a film to surround the silica insulation composite, a PET film with a thickness of approximately 25 μm and an acrylic adhesive applied to one side was prepared (adhesive thickness: approximately 50 μm, total heat generation of the film: approximately 2498 J / g). After placing the silica insulation composite on the center of this PET film, an insulating member with a thickness of approximately 2 to 2.5 mm was manufactured by sealing the front surface of the silica insulation composite as shown in Fig. 4.

[0242]

[0243] [Experimental Example 1] Evaluation of heat blocking efficiency (1)

[0244] 1. Evaluation of time to reach 180°C and heat resistance index (A) of the insulating member

[0245] The heat transfer efficiency of the above-manufactured insulating material was evaluated using equipment with the structure shown in Figures 5 and 6. After placing the insulating material specimens of each example and comparative example on an insulating board, they were left until the temperature of one side of the specimen reached 25±5 ℃ using a temperature sensor located between the specimen and the insulating board. The heating plate was heated to 700 ℃, and the pressure was applied at a pressure of 500 kPa by adjusting the pressure part so that the upper surface of the insulating material specimen came into contact with the heating plate. The temperature of the lower surface of the specimen was measured using a temperature sensor located between the specimen and the insulating board, and the time (in seconds) required for the temperature of the lower surface of the sheet-shaped specimen to reach 180 ℃ was measured from the point when the temperature of the lower surface of the specimen reached 50 ℃. In addition, experiments were performed in the same manner on silica insulation composite specimens prepared in the same way as Preparation Examples 1 to 7 and Comparative Preparation Examples 1 to 5, with dimensions of approximately 75 mm x 75 mm, and the time (in seconds) required for the temperature of the lower surface of the specimen to reach 180 ℃ or 350 ℃ was measured. For each example, the percentage of the time it takes for the temperature of the lower surface of the insulation member to reach 180 ℃ relative to the time it takes for the temperature of the lower surface of the silica insulation composite to reach 180 ℃ was calculated using the 180 ℃ heat resistance index (A) of Formula 1 below, and the results are shown in Table 1 below.

[0246] [Equation 1]

[0247]

[0248] Classification Time to reach 180°C (sec) Heat resistance index (A) (%) Silica insulation composite Insulation member Example 1 29.8 16.6 55.70 Example 2 30.8 18.2 59.09 Example 3 33.2 21.8 65.66 Example 4 29.2 21.6 73.97 Example 5 27.4 21.3 77.74 Example 6 32.1 26.5 82.55 Example 7 28.6 248 3.92 Comparative Example 1 31.2 13.2 42.31 Comparative Example 2 29.2 12.1 41.44 Comparative Example 3 32.6 339.88 Comparative Example 4 28.8 11.7 40.63 Comparative Example 5 34.4 13.2 38.37

[0249] As shown in Table 1 above, in the case of the insulating member containing the silica insulating composite of Comparative Examples 1 to 5, it can be seen that the time to reach a temperature of 180°C is drastically shortened compared to the silica insulating composite without a laminated film. However, for the insulating member containing the silica insulating composite of Examples 1 to 7, the time to reach 180°C is 16 seconds or more even when surrounded by a PET film, and it can be seen that the degree of reduction in the time to reach a temperature of 180°C is small compared to the silica insulating composite without a laminated film.

[0250] 2. Evaluation of time to reach 350 ℃ and heat resistance index (B) of the insulating member

[0251] The experiment was conducted in the same manner as the experiment described in 1 above, but the time (in seconds) for the lower surface of the insulating member and the silica insulating composite to reach a temperature of 350°C was measured, and the heat resistance index (B) of 350°C was calculated according to Equation 2, and the results are shown in Table 2 below.

[0252] [Equation 2]

[0253]

[0254] Classification Time to reach 350 ℃ (sec) 350 ℃ Heat Resistance Index (B) (%) Silica Insulation Composite Insulation Example 1 209.210952.10 Example 2 213115.254.08 Example 3 207.8121.558.47 Example 4 197.6113.157.24 Example 5 189.4118.262.41 Example 6 215.6133.862.06 Example 7 20813563.38 Comparative Example 1 205.67.7.937.89 Comparative Example 2 186.378.241.98 Comparative Example 3 20890.143.32 Comparative Example 4 178.468.938.62 Comparative Example 5 223.896.242.98

[0255] As shown in Table 2 above, in the case of the insulating member containing the silica insulating composites of Comparative Examples 1 to 5, it can be seen that the time to reach a temperature of 350°C is drastically shortened compared to the silica insulating composite without a laminated film. However, for the insulating member containing the silica insulating composites of Examples 1 to 7, the time to reach 350°C is 100 seconds or more, and it was observed that the degree of reduction in the time to reach 350°C is very small compared to the silica insulating composite without a laminated film. From the above experiments, it was found that the silica insulating composite according to the present invention has excellent heat resistance and pore strength, so even when the silica insulating composite is surrounded by a film, the degradation of the thermal insulation performance of the silica insulating composite caused by the film is minimized.

[0256]

[0257] [Experimental Example 2] Evaluation of heat transfer efficiency (2)

[0258] In order to confirm that the silica thermal insulation composite according to the present invention has excellent heat resistance and that the decrease in heat transfer efficiency is suppressed even when sealed with any film, a specimen of the silica thermal insulation composite of Preparation Example 1, with a size of approximately 75 mm X 75 mm, was encapsulated by surrounding it with the films shown in Table 3 below. The time (in seconds) for the thermal insulation member to reach 180 ℃ and 350 ℃ and the heat resistance index (A, B) were calculated in the same manner as in Experimental Example 1 above, and the results are shown in Tables 4 and 5 below.

[0259] PET Film Thickness (㎛) Heat Generation (J / g) Film #1 Approx. 25 ㎛ PET film (approx. 35 ㎛ acrylic adhesive coated) 1854 Film #2 Approx. 40 ㎛ PET film (approx. 40 ㎛ acrylic adhesive coated) 2913

[0260] Classification Time to reach 180 ℃ (sec) Heat resistance index (A) (%) Silica insulation composite insulation material Example 8 (Film #1) 29.8 17.35 8.05 Example 9 (Film #2) 29.8 15.95 3.36

[0261] Classification Time to reach 350 ℃ (sec) Heat resistance index (B) (%) Silica insulation composite insulation material Example 8 (Film #1) 209.211354.02 Example 9 (Film #2) 209.2106.851.05

[0262] As shown in Tables 4 and 5 above, the silica thermal insulation composite according to the present invention has excellent heat resistance and pore strength, and it was confirmed that it still maintains excellent heat insulation performance even when sealed with different PET films of different thicknesses or heat generation amounts. In particular, it was confirmed that the heat insulation efficiency remains high even when sealed with a film with a heat generation amount close to 3000 J / g.

[0263]

[0264] [Experimental Example 3] Evaluation of Thermal Insulation Performance

[0265] In order to evaluate the thermal conductivity of the silica thermal insulation composite manufactured according to the present invention, a silica thermal insulation composite with dimensions of 100 mm x 100 mm was prepared by the methods of each of Manufacturing Examples 1 to 7, and the thermal conductivity at room temperature (25±5℃) was measured using a Netzsch HFM436 instrument, and the results are shown in Table 6 below.

[0266] Thermal Conductivity (mW / mK) Preparation Example 1 20.20 Preparation Example 2 21.35 Preparation Example 3 22.64 Preparation Example 4 22.18 Preparation Example 5 20.28 Preparation Example 6 21.40 Preparation Example 7 19.47

[0267] As shown in Table 6 above, all silica thermal insulation composites according to the present invention (Preparation Examples 1 to 7) had low thermal conductivity and excellent thermal insulation properties. Although not shown in the table above, it was confirmed that even when the entire surface of the silica thermal insulation composite was wrapped with a film in the same manner as the above-described examples, the thermal conductivity increased by only about 1 to 2 mW / mK, and it still possessed excellent thermal insulation performance. Although the present invention has been described above by limited examples, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0268] [Explanation of the symbol]

[0269] 1: Insulation board

[0270] 2: Temperature sensor

[0271] 3: Heating plate

[0272] 4: Pressurizing part

[0273] 10: Psalms

[0274] 10': Insulation board contact surface among the two sides of the specimen

[0275] 10": Heating plate contact surface among the two sides of the specimen

[0276] 100: Silica insulation composite

[0277] 200, 200': Film

[0278] S1, S2: Sealing part

[0279] The present invention relates to an insulating material that can be applied as an insulating material for batteries, and can also be used as an insulating material, thermal insulation material, or non-combustible material in the construction, aviation, automotive, home appliance, semiconductor, or industrial equipment fields.

Claims

1. A silica thermal insulation composite comprising a substrate and a plurality of silica particles and a silica network structure comprising one or more pores; and a thermal insulation member comprising a film surrounding the silica thermal insulation composite, Insulating member having a heat resistance index (A) of 180°C represented by the following Formula 1 that is 50% or more when heat of 700°C is applied to the first surface of the insulating member: [Equation 1] In the above Equation 1, the time to reach 180°C (seconds) of the insulating member refers to the time (seconds) when the temperature of the second surface of the insulating member reaches 180°C, and the time to reach 180°C (seconds) of the silica insulating composite refers to the time (seconds) when the temperature of the second surface of the silica insulating composite reaches 180°C when heat of 700°C is applied to the first surface of the silica insulating composite that is not surrounded by a film.

2. In Paragraph 1, An insulating member, wherein the time (seconds) required for the temperature of the second surface of the insulating member to reach 180°C is 15 seconds or more.

3. In Paragraph 1, Insulating member having a heat resistance index (B) of 350°C, expressed by the following Equation 2, of 50% or more when heat of 700°C is applied to the first surface of the insulating member: [Equation 2] In the above Equation 2, the time (seconds) to reach 350 ℃ of the insulating member refers to the time (seconds) for the temperature of the second surface of the insulating member to reach 350 ℃, and the time (seconds) to reach 350 ℃ of the silica insulating composite refers to the time (seconds) for the temperature of the second surface of the silica insulating composite to reach 350 ℃ when heat of 700 ℃ is applied to the first surface of the silica insulating composite that is not surrounded by a film.

4. In Paragraph 3, An insulating member, wherein the time (seconds) required for the temperature of the second surface of the insulating member to reach 350 ℃ is 100 seconds or more.

5. In Paragraph 1, The above film is an insulating material having a heat generation capacity of 1,500 to 3,000 J / g.

6. In Paragraph 1, An insulating member having a thickness of 0.5 to 10 mm of the silica insulating composite.

7. In Paragraph 1, An insulating member wherein the above silica network structure comprises silica, methylsilylated silica, dimethylsilylated silica, trimethylsilylated silica, or a mixture thereof.

8. In Paragraph 1, The above silica thermal insulation composite is a thermal insulation member comprising particles in which a plurality of silica particles having a particle size greater than 0 and less than or equal to 5 nm are aggregated or bonded.

9. In Paragraph 8, An insulating member having an average particle size of the aggregated or bonded particles of 5 to 2,000 nm.

10. In Paragraph 1, The density of the above silica thermal insulation composite is 0.05 to 0.50 g / cm³ 3 Phosphorus, insulating member.

11. A battery module comprising: one or more battery cells in an internal space; and an insulating member according to any one of claims 1 to 10.

12. A battery pack comprising the battery module of claim 11.

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