WO2021000927A1 - 一种隔热防火材料及其用途 - Google Patents

一种隔热防火材料及其用途 Download PDF

Info

Publication number
WO2021000927A1
WO2021000927A1 PCT/CN2020/100076 CN2020100076W WO2021000927A1 WO 2021000927 A1 WO2021000927 A1 WO 2021000927A1 CN 2020100076 W CN2020100076 W CN 2020100076W WO 2021000927 A1 WO2021000927 A1 WO 2021000927A1
Authority
WO
WIPO (PCT)
Prior art keywords
heat
insulating
layer
fire
fireproof
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2020/100076
Other languages
English (en)
French (fr)
Inventor
张尤娟
武庭轩
石彦芳
二宫有希
原田大
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toray Fibers and Textiles Research Laboratories China Co Ltd
Original Assignee
Toray Fibers and Textiles Research Laboratories China Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toray Fibers and Textiles Research Laboratories China Co Ltd filed Critical Toray Fibers and Textiles Research Laboratories China Co Ltd
Priority to CN202080044134.7A priority Critical patent/CN113939942B/zh
Publication of WO2021000927A1 publication Critical patent/WO2021000927A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/658—Means for temperature control structurally associated with the cells by thermal insulation or shielding
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/659—Means for temperature control structurally associated with the cells by heat storage or buffering, e.g. heat capacity or liquid-solid phase changes or transition
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the invention relates to a heat insulation and fireproof material and its use.
  • heat-insulating and fire-resistant materials are generally formed of high-temperature-resistant flame-retardant inorganic materials, such as mica materials.
  • inorganic materials such as mica materials.
  • the overall weight of the battery increases, which is not conducive to the lightweight of electric vehicles, thereby affecting the range of electric vehicles.
  • mica flakes are hard and brittle, and are extremely difficult to compress in the thickness direction.
  • the mica sheet is squeezed but difficult to be compressed.
  • mica materials have good heat resistance, they have poor thermal conductivity. Therefore, it is necessary to develop a heat insulation and fire prevention effect, but also good compression resilience, even under the influence of temperature, it can withstand the dimensional changes caused by the deformation of the battery.
  • Japanese Laid-open Patent Publication No. 2018-179010 discloses a fire-resistant and heat-insulating sheet. Since this invention puts a laminated heat-insulating body in a bag made of fire-resistant fibers, it will be exposed to external forces during use. In the phenomenon of vibration or compression, the insulation body and the bag body will be separated under the action of shearing, and it is impossible to guarantee that the whole sheet can play the role of heat insulation.
  • the surface of the inorganic fiber is smooth and rigid, the entanglement force between the fibers constituting the non-woven fabric is small, and the adhesion of the aerogel is also unstable, resulting in poor mechanical properties of the overall insulation, and the density of the inorganic fiber itself is high.
  • the formed non-woven fabric has a high weight and a large thickness, resulting in a large weight and large volume of the refractory and thermal insulation sheet, and it is impossible to achieve lightweight.
  • Si(OH) 4 undergoes dehydration and condensation reaction to generate H 2 O by heating, but the water generated by the reaction is very limited, and significant Endothermic cooling effect.
  • Japanese Laid-open Patent Publication No. 2018-118489 discloses an aerogel laminated composite and a heat insulation material. Since the aerogel in the invention is distributed in layers alone, it lacks a supporting and reinforcing substrate. Therefore, when squeezed by an external force, it is easily compressed and deformed, and after the external force is removed, the compressed part cannot be restored.
  • Chinese published patent CN207425974U discloses a battery box thermal runaway blocking protection sheet.
  • This utility model has a low bonding strength due to the polymer film around the fiber felt, and the battery cell vibrates when the car is running, and is The friction of the thermal insulation felt causes the edge of the polymer film to peel off, and the aerogel powder in it is scattered, which causes the thermal insulation performance of the protective sheet to decrease.
  • the protective sheet also includes an explosion-proof layer made of a metal material as an encapsulation layer, which causes the overall weight of the protective sheet to increase, and it is difficult to achieve weight reduction.
  • FIG. 1 Another example is the Chinese Patent CN108689678A discloses a fiber-reinforced aerogel mat with no large particles of aerogel attached on the surface and a preparation method thereof.
  • the overall specific gravity of the fiber mat is small, and the pores are large and large. Adhesion, even after adhesion, the aerogel particles are likely to fall off, which affects the insulation performance of the material.
  • the whole roll of normal pressure dipping method is adopted in this invention, which will result in poor dispersion uniformity of the aerogel in the rolled fiber mat, and uneven dipping of the outer layer and the inner layer, thereby affecting the insulation of the felt. Stability of performance.
  • the purpose of the present invention is to provide a heat-insulating and fire-proof material with good flame retardancy, high temperature resistance, low thermal conductivity and light weight.
  • the heat-insulating fireproof material of the present invention contains at least a heat-insulating layer
  • the heat-insulating layer contains a porous material and hollow particles
  • the bulk density of the porous material is 0.05 to 0.30 g/ cm 3
  • the average diameter of the hollow particles is 30-1000 ⁇ m
  • the thermal conductivity at room temperature of the heat-insulating and fire-resistant material after carbonization treatment is 0.040 W/(m ⁇ K) or less.
  • the above heat-insulating fireproof material also contains a sealing layer, the sealing layer is a continuous sheet material, the sealing layer is located on at least two opposite sides of the heat-insulating layer, and the average total thickness of the sealing layer accounts for the total thickness of the heat-insulating fire-proof material
  • the ratio is preferably 0.5 to 90%.
  • the above-mentioned heat-insulating fireproof material also contains a heat storage material, the heat storage material is hydrate or metal hydroxide, and the weight ratio of the water released when the heat storage material is heated to the weight of the heat-insulating fireproof material is preferably 2.0 ⁇ 25.0%.
  • the above-mentioned heat storage material preferably has a layered structure distributed on opposite sides of the heat insulation layer, and the ratio of the average thickness of the heat storage layer to the average thickness of the heat insulation layer is preferably 10 to 90%.
  • the above-mentioned heat storage material is preferably dispersed in the heat insulating layer.
  • the above-mentioned heat storage material is preferably dispersed in the sealing layer.
  • the porous material is preferably a fibrous structure.
  • pores having a pore diameter between 5 and 50 ⁇ m preferably account for 50% or more of all pores.
  • the thermal conductivity of the fiber structure is preferably less than 0.040 W/(m ⁇ K).
  • the above-mentioned fiber structure is preferably a non-woven fabric containing thermoplastic fibers having an LOI value of 28% or more and non-melting fibers.
  • the above-mentioned hollow fine particles are preferably aerogel powder.
  • the weight ratio of the aerogel powder in the heat insulating and fireproof material of the present invention is preferably 15% or more.
  • the airtightness of the continuous sheet material is preferably 20 cm 3 /cm 2 /s or less.
  • the aforementioned continuous sheet-like material is preferably a film-like material, a sheet formed of a fiber textile, or a sheet-like material formed of a continuous resin.
  • the temperature difference between the two sides of the heat insulating and fireproof material of the present invention is preferably greater than 300°C.
  • the heat insulating and fireproof material of the present invention has the characteristics of excellent heat insulation and fire resistance, and light weight.
  • the thermal insulation and fireproof material of the present invention can be used as a buffer and thermal insulation material between the cells of a power battery, can effectively block the transfer of thermal insulation energy, is fireproof and flame retardant, slows down the transfer speed of huge heat and flame when the cell explodes, and slowly Conduct heat to adjacent batteries, thereby prolonging the escape time of drivers and passengers and playing a role of safety protection.
  • FIG. 1 is a schematic diagram of the thermal insulation and fireproof material of the present invention.
  • A is the thermal insulation layer
  • B is the thermal storage layer
  • C is the sealing layer
  • the thermal storage layer B is distributed on both sides of the thermal insulation layer A, where a is Porous material, b is hollow particles, c is continuous sheet material, and d is heat storage material.
  • FIG. 2 is a schematic diagram of the heat insulation and fireproof material of the present invention.
  • A is the heat insulation layer
  • B is the heat storage layer
  • C is the sealing layer.
  • the heat storage layer and the sealing layer are the same layer, where a is a porous material, b is hollow particles, c is a continuous sheet material, and d is a heat storage material.
  • FIG. 3 is a schematic diagram of the thermal insulation and fireproof material of the present invention.
  • A is the thermal insulation layer
  • B is the heat storage layer
  • C is the sealing layer.
  • the thermal insulation layer and the heat storage layer are the same layer, where a is a porous material , B is hollow particles, c is continuous sheet material, and d is heat storage material.
  • the heat-insulating fireproof material of the present invention contains at least a heat-insulating layer, the heat-insulating layer contains a porous material and hollow particles, the bulk density of the porous material is 0.05 to 0.30 g/cm 3 , and the hollow particles are The average diameter is 30-1000 ⁇ m, and the thermal conductivity at room temperature of the heat-insulating and fire-resistant material after carbonization treatment is 0.040W/(m ⁇ K) or less.
  • Porous material refers to a material with a network structure composed of interpenetrating or closed pores. The material has a certain thickness.
  • the porous material is a foamed porous material, a metal powder sintered porous material, a fiber structure, etc., preferably a fiber structure , Because the fiber structure has better compression recovery, compression deformation occurs under external force, and after the external force is removed, the fiber structure can recover faster and eliminate the compression deformation.
  • Hollow particles refer to particles with hollow structures or cavities, where the cavities can be completely enclosed or partially enclosed.
  • the hollow particles are hollow silica particles, hollow glass beads, hollow ceramic particles, etc., preferably hollow silica particles, that is, silica aerogel particles, because hollow silica particles have high porosity and high specific surface area. , And light weight, with excellent heat insulation performance.
  • the silica aerogel powder of appropriate particle size maintains the nanoporous structure of the aerogel, making it easier to disperse and fill, and then composite with porous materials, that is, hollow particles can be effectively contained and attached to the structure containing holes
  • the porous material supports the hollow particles to form an integrated heat-insulating layer.
  • the resulting heat-insulating layer has certain mechanical strength and functionality, such as fire prevention and heat insulation.
  • the bulk density of the porous material of the present invention must be controlled within a certain range. If the bulk density of the porous material is lower than 0.05g/cm 3 , there are too many pores in the material, and even larger through-type pores will appear. The hollow particles on the porous material will fall out of the large pores, and the hollow particles cannot even accumulate, and the resulting heat insulation layer will not have the effect of heat insulation; if the bulk density of the porous material is higher than 0.30g/cm In the case of 3 , the porous material becomes dense, the pores in the porous material become smaller and less, and the adhesion amount of hollow particles decreases, and even cannot enter the interior of the porous material, which greatly reduces the thermal insulation performance of the thermal insulation layer.
  • Hollow particles have a hollow or cavity structure and can store air. Hollow particles of suitable particle size are attached and accumulated in the porous material, which can greatly reduce the barrier properties of the heat insulation and fireproof material of the present invention to heat transfer. If the hollow particles are average If the diameter is less than 30 ⁇ m, the contact area between the hollow particles dispersed in the porous material and the porous material becomes smaller, which makes it difficult for the hollow material to adhere, and it is prone to scattering and falling, which will cause the insulation performance to decrease; if the hollow particles If the average diameter is greater than 1000 ⁇ m, it is difficult for the large hollow particles to enter the internal pores of the porous material, but only float on the surface of the porous material, which is very easy to fly and fall during use, and the thermal insulation performance is greatly reduced.
  • the average diameter of the hollow particles is preferably 50 to 800 ⁇ m, more preferably 50 to 500 ⁇ m.
  • the average diameter of the hollow particles herein refers to the particle diameter of the aggregate composed of the three-dimensional network structure of the aerogel for aerogel particles.
  • the thermal conductivity of the heat-insulating and fire-proof material of the present invention after carbonization treatment is 0.040 W/(m ⁇ K) or less at room temperature.
  • thermal insulation and fireproof materials must have excellent thermal insulation properties, especially When the battery core is out of control, the heat-insulating and fire-resistant materials will be instantly carbonized by high temperature. At this time, the heat-insulating and fire-resistant materials are required to maintain good thermal insulation performance after carbonization to avoid chain loss of control.
  • thermal conductivity of the thermal insulation and fireproof material at room temperature after carbonization is higher than 0.040W/(m ⁇ K), that is, carbonization occurs when the thermal insulation material is subjected to high temperature, and its thermal conductivity becomes higher, which is produced by the cell that is thermally out of control.
  • the high temperature cannot be blocked, heat diffusion reaction occurs, causing rapid heat transfer, and further rapid heat conduction to adjacent cells, causing adjacent cells to instantaneously cause chain thermal runaway, further aggravating the battery burning speed, reducing driving The valuable escape time of passengers can even lead to serious casualties.
  • the thermal conductivity of the heat-insulating fire-proof material of the present invention after carbonization treatment is preferably 0.020 to 0.040 W/(m ⁇ K) at room temperature.
  • the heat insulating and fireproof material of the present invention preferably contains a sealing layer, the sealing layer is a continuous sheet material, the sealing layer is located on at least two opposite sides of the heat insulating layer, and the average total thickness of the sealing layer accounts for the heat insulating fireproof material
  • the ratio of the overall thickness is preferably 0.5 to 90%. Due to the hollow particles attached to the porous material in the thermal insulation layer, during the packaging, transportation and use of the thermal insulation material, the hollow particles are prone to flying and falling due to external force, which directly affects the thermal insulation performance of the material. When the material is used as a thermal insulation buffer material between the cells, the thermal insulation becomes poor or uneven. Once the cells heat up abnormally, the heat transfer cannot be effectively blocked in time, causing the cells to heat up.
  • the sealing layer is a continuous sheet material, which can effectively prevent the hollow particles in the heat insulating layer from scattering and maintain the heat insulating performance to the greatest extent. Since the insulation layer is a material with a certain thickness, it can be regarded as a cuboid. Therefore, the sealing layer can be located on two opposite sides of the thermal insulation layer, or on four or six sides of the thermal insulation layer.
  • the sealing layer When the sealing layer is located on two opposite sides of the thermal insulation layer, the two sides are rectangular parallelepiped and the insulation layer occupies the largest area
  • the opposite sides of the insulation layer namely the upper and lower surfaces of the insulation layer, can prevent the hollow particles in the insulation layer from being vibrated or squeezed by external force to fly and fall off. It can also be produced quickly and at low cost.
  • the sealing layer When the sealing layer is located on four or six sides of the insulating layer, that is, the sealing layer not only covers the upper and lower surfaces of the insulating layer, but also covers the sides of the insulating layer. At this time, the insulating layer can be completely prevented Since the hollow particles are vibrated or squeezed by an external force to scatter and fall off, it is more preferable that the sealing layer is located on four or six sides of the heat insulating layer.
  • the average thickness of the sealing layer is preferably 5 to 200 ⁇ m. If the average thickness of the film-like material is too thin, it will be easily damaged by the thermal expansion and friction between the cells on both sides, causing the hollow particles in the thermal insulation layer to fly and fall, causing a decrease in thermal insulation; If the average thickness of the shaped material is too thick, the compressible space is too small due to the high density, and even after being compressed, its resilience is poor. When the battery core cools to restore the original thickness, the heat insulation and fireproof material cannot recover as a whole To the original thickness, there will be gaps between adjacent cells, and the thermal insulation and fireproof materials will loosen.
  • the average thickness of the sealing layer is preferably 100-400 ⁇ m. If the thickness of the fiber textile is too thin, it will be easily damaged by the thermal expansion and friction between the electric cores on both sides, causing the hollow particles in the heat insulation layer to fly and fall, causing the heat insulation to decrease; if the fiber textile is If the thickness is too thick, the overall thickness of the heat-insulating fireproofing material is limited, generally not exceeding 4mm, so that the thickness of the heat-insulating layer or the thickness of the heat storage layer can only be reduced, resulting in a decline in the overall performance of the heat-insulating fireproofing material.
  • high-density flame-retardant fiber textiles with a thickness of 100-200 ⁇ m are preferred as the sealing layer, which can not only prevent the hollow particles in the heat insulation layer from flying and falling, but also improve the deformation resistance and shear resistance of the heat insulation and fire protection material. It even plays a role of flame retardant and fire prevention. When the battery is on fire, it can prevent the flame from spreading and slow down the heat transfer.
  • the sealing layer is a resin-formed sheet material
  • the resin-formed sheet material contains a heat storage material
  • the more heat storage material it contains the greater the thickness of the sheet material formed by the resin.
  • the more heat absorption is.
  • the average thickness of the sealing layer is preferably 200 to 1000 ⁇ m.
  • the thickness of the resin-formed sheet material is too thin, the heat storage material contained in the resin layer is too small, and the amount of heat that can be absorbed decreases, resulting in a decrease in the overall thermal insulation of the heat-insulating fireproof material; if the resin-formed sheet If the thickness of the shaped material is too thick, the overall thickness of the heat-insulating fireproof material is limited, generally not exceeding 4mm, so the thickness of the heat-insulating layer becomes thinner, and the heat insulation performance decreases, which will also cause the overall heat insulation performance of the heat-insulating fireproof material to decrease .
  • the ratio of the average total thickness of the above-mentioned sealing layer to the overall thickness of the heat-insulating and fire-resistant material is preferably 0.5-90.0%.
  • the average total thickness of the sealing layer in the present invention refers to the average thickness distributed on the upper and lower surfaces of the insulating layer.
  • the overall thickness of the heat-insulating and fire-proof material refers to the distance between the upper and lower surfaces of the heat-insulating and fire-proof material of the present invention, that is, includes all the thicknesses of the heat-insulating layer, the heat storage layer and the sealing layer.
  • the ratio of the average total thickness of the sealing layer to the overall thickness of the heat-insulating fire-retardant material can reflect the sealing performance of the sealing layer to the hollow material on the one hand, and it also directly affects the overall compression recovery performance of the heat-insulating fire-retardant material. If the ratio of the average total thickness of the sealing layer to the overall thickness of the heat-insulating and fire-proofing material is too low, it means that the sealing layer is too thin.
  • the friction force easily breaks the continuous state of the too thin sealing layer, which causes the hollow particles uniformly dispersed in the porous material to fall due to external forces such as vibration, and the hollow particles fall out from the pores of the porous material, resulting in hollow particles
  • the adhesion amount of the battery becomes less and the distribution is uneven.
  • the battery core When the battery core is thermally out of control, it cannot have a good heat insulation and fire prevention effect, resulting in rapid heat transfer to the adjacent battery core, causing a chain reaction; if the average total thickness of the sealing layer accounts for the partition If the proportion of the overall thickness of the thermal fireproof material is too high, it means that the sealing layer is too thick.
  • the resulting thermal insulation fireproof material When the resulting thermal insulation fireproof material is installed between the cells, it will be squeezed by the thermally expanded cells on both sides. High, the compressible space is too small, and even after being compressed, its resilience is poor.
  • the battery core cools and restores its original thickness, the heat insulation and fireproof material cannot return to its original thickness as a whole, resulting in gaps. The cell becomes loose, and even deforms and fails.
  • the ratio of the average total thickness of the sealing layer to the overall thickness of the heat-insulating and fire-resistant material is too high, that is, the thickness of the heat-insulating layer is too thin, and there are too few porous materials and hollow particles in the heat-insulating layer, which is the main body of the heat-insulation. Can not provide sufficient heat insulation performance for the material.
  • the prepared heat insulation and fire protection material is installed between the cells, it will not have a good heat insulation and fire protection effect when the cells are thermally out of control, resulting in heat quickly being transferred to the phase. Adjacent batteries cause a chain reaction.
  • the average total thickness of the sealing layer of the present invention accounts for the thermal insulation and fire protection
  • the ratio of the overall thickness of the material is more preferably 10.0 to 70.0%, and still more preferably 25.0 to 50.0%.
  • the thermal insulation and fireproof material of the present invention preferably contains a heat storage material, which can make up for the limitation of the pure heat insulation layer in the thermal insulation and fireproof material on heat blocking effect, especially when the heat insulation and fireproof material is in an environment where the temperature rises sharply Below, the heat storage material can effectively suppress the temperature rise.
  • the heat storage material is a hydrate or a metal hydroxide, and the weight ratio of the water released when the heat storage material is heated relative to the weight of the heat insulating and fireproof material is preferably 2.0-25.0%. Hydrate refers to a compound containing water, usually refers to crystal hydrate, that is, a substance containing a certain amount of crystal water, and its sources are quite wide.
  • the water in the hydrate can be connected to other parts by coordination bonds, such as hydrated metal ions, the chemical formula is KAl(SO 4 ) 2 ⁇ 12H 2 O, or it can be combined by covalent bonds, such as hydrated chloroacetaldehyde.
  • Some crystal hydrates can automatically lose part or all of the crystal water at room temperature and dry air. This phenomenon is called weathering. Therefore, this kind of crystal hydrate does not exist because of the loss of water at room temperature, and some crystals Hydrates need to occur under certain heating conditions. When hydrates are heated, hydrolysis or dehydration reactions occur, that is, water molecules are lost when heated.
  • the loss of water molecules can occur within the compound molecule, that is, intramolecular dehydration, or between two molecules of the same compound, that is, intermolecular dehydration.
  • the water of the hydrate undergoes an endothermic reaction and can absorb heat, thereby reducing heat conduction.
  • Metal hydroxides refer to inorganic compounds formed by metal cations and hydroxide ions (-OH), which can generate metal oxides and water when heated, and can absorb heat.
  • the thermal decomposition starting temperature of Al(OH) 3 is about 220°C
  • the thermal decomposition starting temperature of Mg(OH) 2 is about 340°C
  • NaOH is difficult to decompose by heating. .
  • This is related to the metallicity of the metal in the metal hydroxide. Generally speaking, the stronger the metallicity, the higher the stability of the hydroxide.
  • metal hydroxides with a decomposition temperature of 100 to 1200°C are preferred, such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide and the like.
  • the decomposition temperature is in the range of 100 to 1200°C, but also metal hydroxides having a heat storage density of 600 kJ/kg or more, such as aluminum hydroxide.
  • the heat storage density here can represent the ability of the material to absorb heat per unit weight. If the heat storage density of the heat storage material is too low, it will not be able to absorb a large amount of heat generated by the battery when the temperature rises sharply. It absorbs heat quickly to reach saturation and no longer absorbs heat, which cannot effectively delay the rise of the temperature of the cell, thereby affecting the overall thermal insulation performance of the material.
  • the heat storage density of the chemical heat storage material is more preferably 1000 kJ/kg or more.
  • the weight ratio of the water released by the heat storage material when heated relative to the weight of the heat-insulating fireproof material is preferably 2.0-25.0%, if the weight of the water released when the heat storage material is heated and decomposed relative to the weight ratio of the heat-insulating fireproof material If it is too low, the water released after heating can absorb less heat, that is, thermal decomposition can occur under lower heat conditions.
  • heat storage materials are used between the cells, If the abnormal heating of the cell causes thermal runaway, when the heat storage material contacts the cell whose temperature rises sharply, it will not be able to quickly absorb the large amount of heat generated by the cell, so that it will not be able to effectively block the transfer of heat insulation to adjacent cells. In severe cases, a chain explosion will occur.
  • the weight ratio of the heat insulation layer as the main body of the heat insulation must be reduced, that is, the porous material in the heat insulation layer
  • the decrease in the weight ratio of the hollow particles directly leads to the decrease of the overall thermal insulation performance of the thermal insulation fireproof material, which cannot provide sufficient thermal insulation performance.
  • the thermal insulation effect is poor. As a result, more heat is quickly transferred to adjacent cells, and a chain reaction occurs, resulting in thermal runaway of the battery as a whole.
  • the weight ratio of the moisture released when the heat storage material is heated to the weight of the heat insulating and fireproof material is more preferably 5 to 20%.
  • the heat-insulating fire-proof material of the present invention preferably contains a heat storage material, and the heat storage material is present in the heat-insulating fire-proof material in the following manner.
  • Method 1 Mix the heat storage material with the heat-meltable solid flame-retardant binder particles to obtain mixed particles, and spread the mixed particles evenly on the upper and lower sides of the pre-prepared heat insulation layer.
  • a layer of heat storage powder layer is formed in the form of a film, which is the heat storage layer, and then a continuous sheet material is used to encapsulate at least two opposite sides, and the two are initially consolidated by heating, melting, cooling and solidifying to form a distributed heat insulation layer.
  • the heat storage layer on both sides of the layer is encapsulated by a continuous sheet material as an integral heat insulation and fireproof material.
  • Method 2 Mix the heat storage material and the liquid flame-retardant resin uniformly to form the flame-retardant resin liquid of the heat storage material, and then evenly coat it on the upper and lower sides of the pre-prepared heat insulation layer at a suitable temperature After drying and solidifying, cooling at room temperature, a layer of flame-retardant resin cured film with heat storage material powder attached is formed on both sides of the heat insulation layer, and finally the heat storage layer distributed on both sides of the heat storage layer and the sealing layer are integrated In this case, the heat storage layer is the sealing layer.
  • the above-prepared flame-retardant resin cured film with heat storage material particles attached can not only absorb a large amount of heat, but also solve the problem that hollow particles inside the porous material are scattered from the pores of the porous material.
  • Method 3 Sprinkle the heat storage material powder into the pre-prepared porous material containing hollow particles, and make the heat storage material powder fully enter the gap between the porous material and the hollow particles by physical filling, to obtain a barrier
  • the heat layer is also a heat storage layer, and then a continuous sheet material is used to encapsulate at least two opposite sides to form the heat insulation layer and the heat storage layer in the same layer structure, and the continuous sheet material is encapsulated as an integral heat insulation and fireproof material.
  • the preparation method of the heat-insulating and fire-proof material of the present invention is not limited to the above three, and the above-mentioned three methods can also be cross-used to obtain a heat-insulating and fire-proof material that has both heat insulation and fire resistance and is lightweight.
  • the heat storage material of the present invention preferably has a layered structure distributed on opposite sides of the heat insulation layer, and the ratio of the average thickness of the heat storage layer to the average thickness of the heat insulation layer is preferably 10-90%.
  • the heat storage layer is preferably distributed on opposite sides of the heat insulation layer, and since the heat insulation layer has a certain thickness, it can be regarded as a cuboid.
  • the opposite sides of the thermal insulation layer refer to the two opposite sides that occupy the largest area in the thermal insulation layer of the cuboid, namely the upper and lower surfaces.
  • the two opposite sides of the heat insulation layer are in direct surface contact with the battery core.
  • the battery core Once the battery core is thermally out of control, it can most effectively block the heat from the battery core, thereby delaying the thermal runaway of adjacent cells and avoiding chain reactions . If the ratio of the average thickness of the heat storage layer to the average thickness of the heat insulation layer is too low, that is, the ratio of the average thickness of the heat storage layer is too small, the heat storage material in the heat storage layer plays a role of heat storage is less, and the heat is decomposed The amount of heat that can be absorbed at the time is also reduced sharply, which does not have the effect of absorbing heat and suppressing temperature rise, but can only rely on the heat insulation effect of the heat insulation layer, so that the heat insulation conduction cannot be fully blocked, and the heating and heating of adjacent cells are increased.
  • the ratio of the average thickness of the heat storage layer to the average thickness of the insulation layer is too high, that is, the ratio of the average thickness of the insulation layer is too small, and the thickness of the insulation layer is too thin.
  • the content of the porous material and hollow particles contained in the thermal layer is too small. Especially when the content of hollow particles is reduced, the through pores contained in the porous material may be directly exposed, and high-temperature heat on one side will pass through the The pores are directly transmitted to the opposite side and cannot effectively block the heat insulation.
  • the thickness of the heat insulation layer is too thin, that is, the thickness of the layer where the hollow particles are located is too thin, the air barrier layer that the hollow particles can form becomes thinner. As we all know, air is an excellent thermal insulation material.
  • the air barrier layer becomes thinner, the heat barrier effect is directly deteriorated, that is, heat can be easily transferred from one side of the insulation layer to the other.
  • the prepared heat insulation and fireproof material is installed between the cells, when the cells are thermally out of control, the too thin insulation layer cannot have a better heat insulation and fire prevention effect, which causes the heat to be quickly transferred to the adjacent The battery cell causes a chain thermal runaway reaction.
  • the ratio of the average thickness of the heat storage layer to the average thickness of the heat insulation layer is more preferably 15-85%.
  • the average thickness of the above-mentioned heat storage layer is preferably 100-2000 ⁇ m.
  • the thickness of each side heat storage layer is preferably 50-1000 ⁇ m. The more heat storage material contained in the heat storage layer, the thicker the heat storage layer formed and the more heat absorption, but the final heat insulation and fireproof material will have a higher thickness.
  • the thickness of the heat storage layer on one side at this time is more preferably 50 to 200 ⁇ m.
  • the thickness of the heat storage layer on one side is preferably 200-1000 ⁇ m.
  • the thickness of the heat storage layer on one side is too thin, because the heat storage material contained is too small, it will not be able to absorb the large amount of heat generated by the battery when the temperature rises sharply, and the heat storage material will quickly saturate and no longer absorb heat. , Unable to effectively delay the temperature rise of adjacent cells, resulting in a decrease in the overall thermal insulation of the thermal insulation fireproof material.
  • the average thickness of the heat insulating layer is preferably 600 to 2400 ⁇ m.
  • the heat insulation layer contains porous materials and hollow particles, and plays an important role in heat insulation and fire protection materials. If the thickness of the thermal insulation layer is too thin, when the thermal insulation and fireproof material is used as a thermal insulation buffer between the cells, once the cells rise abnormally during use, the heat transfer cannot be effectively blocked in time , Resulting in continuous thermal runaway of the battery, and in severe cases, it will cause the drivers and passengers to escape too late and cause serious casualties; if the thickness of the insulation layer is too thick, it needs to be adjusted by reducing the thickness of the heat storage layer or the sealing layer. After the thickness of the thermal layer is reduced, it cannot absorb a large amount of heat energy generated instantaneously when it comes into contact with a battery whose temperature rises sharply.
  • the heat storage material is dispersed in the heat insulation layer.
  • the heat-insulating fireproof material is prepared by the above method three, the heat storage material powder is sprinkled into the previously prepared porous material containing hollow particles, and the heat storage material powder is fully infiltrated into the porous material and the porous material through physical filling.
  • a heat-insulating layer is made, which is also a heat storage layer, and then a continuous sheet material is used to encapsulate at least two opposite sides to form the same layer structure of the heat-insulating layer and the heat storage layer, and the continuous sheet material Encapsulated as an integral heat insulation and fireproof material.
  • the heat storage material is dispersed in the heat insulation layer and mixed with hollow particles. When it comes into contact with high-temperature objects, it can play the role of heat insulation and heat absorption at the same time, and quickly block the transfer of heat insulation.
  • the heat storage material is preferably dispersed in the sealing layer.
  • the heat-insulating fireproof material is prepared by the above method two, the heat storage material and the liquid flame-retardant resin are uniformly mixed to form the flame-retardant resin liquid of the heat storage material, and then it is uniformly coated on the pre-prepared heat insulation layer
  • the upper and lower sides are dried and solidified at a suitable temperature and then cooled at room temperature.
  • a layer of flame-retardant resin cured film attached with heat storage material powder is formed on both sides of the heat insulation layer to form heat storage distributed on both sides of the heat insulation layer
  • the layer is an integrated heat-insulating and fire-proof material, at this time, the heat storage layer is the sealing layer.
  • the above-prepared flame-retardant resin cured film with heat storage material particles attached can not only absorb a large amount of heat, but also solve the problem that hollow particles inside the porous material are scattered from the pores of the porous material.
  • the heat storage material is dispersed in the sealing layer, that is, distributed on at least two opposite sides of the heat insulation layer. By adjusting the thickness of the sealing layer, the amount of heat storage material used can be precisely controlled.
  • the heat storage materials dispersed on the outside can thermally decompose and absorb heat for the first time, slowing down heat transfer. Then, the heat insulation layer further blocks the heat, while part of the heat continues to be transferred to the heat storage layer away from the heat source.
  • the heat storage layer continues to undergo thermal decomposition to absorb heat, and the functions of heat insulation and heat absorption are most effectively exerted, thereby ensuring heat insulation Fireproof material has excellent heat insulation performance.
  • the porous material of the present invention is preferably a fibrous structure.
  • the fiber structure refers to an aggregate formed of fibers, such as a non-woven fabric.
  • the non-woven fabric has a certain thickness, is easy to form a porous structure, and has a certain compression resilience performance, and if used as a supporting substrate, it has good performance and is therefore preferred.
  • the form of the nonwoven fabric may be needle punched, spunlaced, etc., and considering the composite processing with the aerogel material, the form of the fiber structure is more preferably a needle punched nonwoven fabric having a porous structure.
  • the needle punch density is preferably 100 needles/cm 2 or more, and the needle punch density is more preferably 150 needles/cm 2 or more.
  • the resulting fiber structure has more entanglement between fibers and friction It has stronger cohesion and overall higher tensile strength, higher shear strength and shear modulus. That is, the needling density of the non-woven fabric is particularly important. If the needling density is too low, the necessary mechanical properties such as stretching and shearing cannot be guaranteed; if the needling density is too high, the non-woven fabric layer will be repeatedly pierced.
  • the shear strength and shear modulus of the heat insulating and fireproof material of the present invention are preferably above 1 MPa.
  • the heat insulation and fireproof material of the present invention is applied to the battery. Because the initial interval between the two cells in the battery is relatively fixed, when the battery is in use or charging, a large amount of heat will be generated, and the cells will be heated. When expansion occurs, the thickness increases, and the interval between the two cells becomes narrower.
  • the fiber structure can provide better compression resilience performance, can absorb the swelling stress of the cell, and play a buffering effect. That is, the fiber structure of the present invention can be compressed when the cell is heated and expanded, and when the cell is cooled After shrinking, it can return to its original thickness.
  • the batteries constantly vibrate and relative displacement during the movement of the car, which drives the heat-insulating and fire-proof materials to produce friction and shear. Therefore, it is necessary for the heat-insulating and fire-resistant material to have good shear strength and shear modulus.
  • pores having a pore diameter between 5 and 50 ⁇ m preferably account for more than 50% of all pores.
  • the porous structure in the fiber structure facilitates the attachment and fixation of the aerogel powder, thereby giving the fiber structure better heat insulation. If the pores in the fiber structure are too large, the aerogel powder will easily scatter and the uniformity of dispersion will be poor; if the pores in the fiber structure are too small and the surface tension is too large, the aerogel powder will not easily enter the inside of the pores , Adhesion becomes worse, and it is easy to fly and fall when vibrated by external force.
  • the aerogel powder dispersed in the liquid enters the pores in the fiber structure during composite processing, and it is easy to flow and quickly It flows out from the holes in the fiber structure, causing the aerogel powder to not be uniformly dispersed, and the thermal insulation performance is deteriorated.
  • the pores with a pore diameter of 5-50 ⁇ m in the above-mentioned fiber structure more preferably account for 50-95% of all pores.
  • the thermal conductivity of the fiber structure in the heat-insulating and fire-proof layer of the present invention is preferably lower than 0.040 W/(m ⁇ K).
  • the fiber structure that constitutes the main body must have excellent thermal insulation. If the thermal conductivity of the fiber structure at room temperature is too high, it will not be able to effectively play the role of heat insulation, inhibit heat diffusion, and will not delay the spread of fire. It may also quickly conduct heat to adjacent cells, causing rapid heat transfer, resulting in The chain heat is out of control, which reduces the time of escape and leads to accidents.
  • the above-mentioned fiber structure is preferably a non-woven fabric containing thermoplastic fibers having an LOI value of 28% or more and non-melting fibers.
  • Thermoplastic fibers with LOI values above 28% include but are not limited to flame-retardant polyester fibers, polyphenylene sulfide fibers, polytetrafluoroethylene fibers, etc.
  • Non-melting fibers include, but are not limited to, pre-oxidized fibers, glass fibers, phenolic fibers, etc.
  • the non-melting fibers can be used as a more heat-resistant skeleton support layer, so that the obtained heat-insulating and flame-retardant materials can maintain a certain shape and can withstand deformation.
  • the ratio of thermoplastic fibers to non-melting fibers is 10%: 90% to 80%: 20%. If the ratio of thermoplastic fiber to non-melting fiber is too low, it means that the content of thermoplastic fiber is too small to cover the surface of non-melting fiber evenly.
  • the ratio of thermoplastic fiber to non-melting fiber is too high, the heat insulation and fireproofing material will be excessive when it encounters high temperatures.
  • Thermoplastic fibers will produce droplets, while there are too few non-melted fibers, resulting in thermoplastic fibers that cannot carry the droplets.
  • the resulting heat insulation and fireproof material will undergo droplet perforation, causing heat or flame to quickly and directly transfer to the surrounding electricity. Core, causing large-scale thermal runaway, and even causing casualties to drivers and passengers.
  • the hollow fine particles of the present invention are preferably aerogel powder.
  • Aerogel powder has a nanoporous structure and extremely low density. As an excellent thermal insulation material, it is widely used in pipelines, ships, motor cars, and batteries. However, aerogel has low strength, high brittleness, and poor mechanical properties. If used alone, it cannot exert its thermal insulation properties. Therefore, the aerogel powder is adhered to the surface of the fiber structure, and the fiber structure itself forms a porous structure with crisscrossed fibers.
  • the porous structure can be used as an adhesion substrate for aerogel powder, and can effectively carry the aerogel powder, thereby realizing the excellent heat insulation of the material as a whole.
  • the method for attaching the aerogel powder to the surface of the fiber structure of the present invention is as follows: First, the fiber structure is immersed in a uniformly dispersed aerogel dispersion liquid, and the aerogel powder with a smaller average diameter dispersed in the liquid enters the phase. The inside of the fiber structure is better, and then the fiber structure after fully absorbing the aerogel dispersion is slightly pressurized to remove the excess dispersion on the surface, and then dried at low temperature to obtain the aerogel powder attached to the fiber.
  • the surface of the structure is composite material, and the composite material is finally encapsulated, so as to solve the problem that the aerogel powder inside the fiber structure is scattered from the pores in the fiber structure.
  • the weight ratio of the aerogel powder in the heat insulating and fireproof material of the present invention is preferably 15% or more. If the weight ratio of the aerogel powder is too low, that is, the amount of aerogel powder attached to the fiber structure becomes small, and there is even no aerogel powder attached to the fiber structure, resulting in uneven dispersion of the aerogel powder, thereby affecting The uniformity and stability of the thermal insulation performance of the material, and the overall thermal insulation of the material also deteriorate. In consideration of processing cost and thermal insulation performance, the weight ratio of the aerogel powder in the thermal insulation fireproof material of the present invention is more preferably 20 to 80%, and even more preferably 20 to 60%.
  • the airtightness of the continuous sheet material located on the outside of the porous material is preferably 20 cm 3 /cm 2 /s or less, more preferably 15 cm 3 / cm 2 /s or less, more preferably 10 cm 3 /cm 2 /s or less. If the airtightness is too high, the airtightness will deteriorate. When the heat-insulating and fire-proof material is squeezed or impacted by an external force, the aerogel powder inside the fiber structure is likely to scatter and fall. The lower the air tightness, the more the aerogel powder can be sealed and fixed in the fibrous structure, which can effectively play a role in heat insulation, and it is also conducive to mechanical suction cups to transport and assemble materials through negative pressure.
  • the aforementioned continuous sheet-like material is preferably a film-like material, a sheet formed of a fiber textile, or a sheet-like material formed of a continuous resin.
  • the continuous sheet material is a film-shaped material, it is beneficial to the overall weight reduction of the heat-insulating and fire-proof material, and any side of the film-shaped material may also contain a heat-reflecting material.
  • the heat-reflective material can be a heat-reflective paint attached to the surface of the film material, such as thermally evaporated aluminum, or it can be a heat-reflective continuous sheet material, such as aluminum foil.
  • the heat-reflective material has obvious heat resistance effect for reducing heat transfer.
  • the film-like material can be a polymer film with good high temperature resistance, such as polyphenylene sulfide film, polyimide film, etc., can also be a conventional polyester film, and can also be a non-high temperature resistant or non-flame retardant type Film, such as polyethylene film.
  • the grammage of the non-high temperature resistant or non-flame retardant type film material is preferably 20 g/m 2 or less, more preferably 15 g/m 2 or less.
  • the film-like material can be partially melted by heating, and then combined with the porous material in the heat-insulating layer; the film-like material can also be bonded with the porous material in the heat-insulating layer through hot melt adhesive powder and other adhesives Combine.
  • the fiber textiles are more preferably textiles composed of flame-retardant fibers, such as aramid fabrics.
  • the form of fiber textile is not limited, and it can be woven fabric, woven fabric or non-woven fabric.
  • the continuous sheet material is a sheet material formed of a continuous resin
  • a coating material with better heat resistance or flame retardancy is preferred.
  • the temperature difference between the two sides of the heat insulating and fireproof material of the present invention is preferably greater than 300°C. That is, when one side of the heat insulation and fireproof material is in contact with a high-temperature heat source, the heat is conducted from the higher-temperature heating surface to the lower-temperature non-heating surface. After 20 minutes of heat conduction, the temperature difference between the two surfaces will be greater than 300°C .
  • the electric core located on the side of the heat-insulating and fire-proof material is thermally out of control, its temperature will rise rapidly and quickly transfer the heat to the side surface of the heat-insulating and fire-proof material. At this time, in order to avoid chain thermal runaway of the battery, the heat insulation and fireproof material must have excellent heat insulation performance.
  • the compressive elastic modulus of the heat insulation and fireproof material of the present invention is 3-15%, and certain internal pressure and deformation will occur in the battery core when the lithium ion power battery is charged and discharged. Therefore, the thermal insulation material placed between the cells needs to have a certain compression deformation and a restoring force after compression.
  • the rigidity of the heat insulation and fireproof material is large, that is, the compression deformation is small, the internal pressure in the battery cell cannot be released during the charging and discharging process of the battery, causing the cell shell to be compressed and deformed, reducing the battery system life and safety; if After the heat insulation pad cannot be recovered after compression, the gap between the batteries will become larger, and the batteries will loosen and collide during driving, which will increase the probability of thermal runaway and greatly reduce the safety.
  • the heat-insulating and fire-proof material of the present invention obtains a heat-insulating layer by compounding hollow particles and porous materials, and encapsulating the heat-insulating layer, effectively preventing the flying and falling of the hollow particles, and achieving both heat insulation and fire resistance , And lightweight battery cell thermal insulation buffer material, the thermal insulation and fireproof material can be used in batteries.
  • Bulk density refers to the ratio of the mass of the material to the sum of the volume of the substance, closed pores and open pores, and the unit is g/cm 3 .
  • the unit area weight and thickness of the porous material are measured separately, and then calculated by the following formula, the bulk density of the porous material can be obtained.
  • Test method of unit area weight According to JIS L 1096 ⁇ 1999 8.4, use an electronic balance to weigh a sample of 10cm ⁇ 10cm, and then multiply the obtained data by 100 to get the weight of fabric per square meter after conversion, and measure 5 groups Data, take the average of 5 test results as the final test result of the sample; thickness test method: According to JIS L 1096 ⁇ 1999 8.5, use a handheld thickness meter to test the thickness of the sample, measure 5 sets of data, take 5 times The average of the test results is used as the final test result of the sample.
  • the calculation formula of volume density is as follows:
  • the surface of the porous material is laminated with a sealing material or contains hollow particles and other particles inside, first peel off the surface layer of the sealing material, and then use a solvent with a high affinity for hollow particles or other particles to remove the hollow particles or other particles .
  • the following materials can be selected as solvents, such as water, methanol, ethanol, acetone, n-hexane, methyl acetone, etc., one of them can be used, or a combination of multiple types can be used to prevent the porous material from softening, deforming, or dissolving Any solvent can be used.
  • the cleaning temperature and time can be appropriately selected, but it is necessary to select a solvent that does not soften, deform, or dissolve the porous material.
  • the cleaning can be immersion treatment, or mechanical action can be added, such as ultrasonic cleaning.
  • a drying process is performed, and the temperature and time are selected so that the porous material does not soften, deform, or melt.
  • the weight of the porous material after the first cleaning and drying is measured as W 1 .
  • W 2 When the weight of the porous material after the second washing and drying is measured as W 2 , when the weight loss rate of (W 1 -W 2 )/W 1 ⁇ 100 (%) is less than 0.5%, it can be considered as Hollow particles and other particles are completely removed. Then use the above method to measure the unit area weight and thickness of the porous material, and finally calculate the volume density of the porous material.
  • the hollow particles are sampled and fixed on the sample table for gold plating.
  • the hollow particles are photographed with a scanning electron microscope (SEM) at a magnification of 1000 times.
  • SEM scanning electron microscope
  • the diameter of the hollow particles of 50 samples is measured, and the 50 test results are taken. , Calculate the average value, as the average diameter of the hollow particles.
  • thermal conductivity of thermal insulation and fireproof materials is measured at 25°C.
  • the KS-653D oxygen index tester is used, at room temperature, a mixture of oxygen and nitrogen gas at 23°C ⁇ 2°C is introduced, and the thermoplastic fiber is placed in the fixture and exposed to the flame for 30 seconds. Remove every 5 seconds and observe whether the sample burns. In this way, the ignition temperature of the sample at the lowest oxygen concentration is measured.
  • the oxygen concentration is the LOI value, which is the limiting oxygen index.
  • a digital microscope was used to photograph the cross-sections of the sealing layer and the heat-insulating fire-proof material at a magnification of 50 times, and the cross-section heights of the sealing layer and the heat-insulating fire-proof material at 5 locations were randomly measured, and the average of the 5 test results was taken Value, respectively, as the average thickness of the sealing layer and the heat insulation and fireproof material.
  • the sum of the average thickness of the upper and lower sealing layers is denoted as D 1
  • the average thickness of the entire fire and heat insulation material is denoted as D 2
  • a digital microscope was used to photograph the cross-sections of the heat storage layer and the heat insulation layer at a magnification of 50 times, and the cross section heights of the heat storage layer and the heat insulation layer at 5 locations were measured randomly, and the average of the 5 test results was taken.
  • the capillary flow pore measuring instrument (equipment abbreviation PMI, equipment model CFP-1100-AEX) of American Stovell Company is used to test the pore size of the fiber structure.
  • the principle of the test is: take out the saturated sample to be tested from the wetting solution, put it into the sample chamber and seal it, and then use the gas to flow from the front of the sample to the sample chamber.
  • Using dry samples will also generate flow rate versus pressure data, and store and display it in real time.
  • the calculation of the pore diameter refers to the following formula and uses the application program that comes with the device to calculate the ratio of the pores between 5 and 50 ⁇ m to obtain the final test result.
  • the porous material without the hollow particles attached is weighed, the weight is recorded as S 0 , the weight after the hollow particles are attached is recorded as S 1 , and the weight of the hollow particles is calculated as S 1 -S 0 .
  • the measured porous material When the measured porous material already contains hollow particles, weigh the sample and record it as S 1 , and then use a solvent with a higher affinity for hollow particles to remove the hollow particles.
  • the following materials can be selected as solvents, such as water, methanol, ethanol, acetone, n-hexane, methyl acetone, etc., one of them can be used, or multiple combinations can be used to make the porous material not soft, deformed, or insoluble All solvents can be used.
  • the cleaning temperature and time can be appropriately selected, but it is necessary to select a solvent that does not soften, deform, or dissolve the porous material.
  • the cleaning can be immersion treatment, or mechanical action can be added, such as ultrasonic cleaning.
  • the weight of the porous material after the first washing and drying is measured as A 1 .
  • a 2 when the weight of the porous material after the second cleaning and drying is measured as A 2 , when the weight loss rate of (A 1 -A 2 )/A 1 ⁇ 100 (%) is less than 0.5%, it can be considered as The hollow particles are completely removed. Weigh the weight of the sample at this time and record it as S 0. Calculate the weight of the hollow particles as S 1 -S 0.
  • the calculation formula for the weight ratio of hollow particles is as follows:
  • the weight ratio of hollow particles (%) (S 1 -S 0 )/S 0 ⁇ 100%.
  • the temperature difference between the two sides of the heat insulation and fireproof material is greater than 400°C, and it is judged as excellent, and it is recorded as S; the temperature difference between the two sides of the heat insulation and fireproof material is 300°C ⁇ 400°C, and it is judged as good, and it is recorded as A; If the temperature difference is greater than or equal to 250°C and less than 300°C, it is judged as fair and recorded as B; if the temperature difference between the two sides of the heat insulating and fireproof material is less than 250°C, it is judged as bad and recorded as F.
  • the length is 50mm
  • the fineness is 1.7 dtex
  • the high temperature shrinkage rate is 1.6%
  • the room temperature thermal conductivity is 0.033W/(m ⁇ K) (prepared A needle felt with a gram weight of 200 g/m 2 and a thickness of 2 mm was tested).
  • the polyphenylene sulfide fiber "TORCON" (registered trademark) produced by Toray Co., Ltd. is used.
  • the single fiber diameter is 2.2 dtex (diameter is 14.5 microns), the length is 51mm, the product name is S371, the LOI is 34%, and the melting point is 284.
  • °C the glass transition temperature is 90 °C, the number of crimps is 14 (pieces/25mm), and the crimp rate is 15%.
  • the model is AG-D.
  • the thermal conductivity of the aerogel powder at room temperature is 0.018W/(m ⁇ K)
  • the porosity is 90%
  • the surface area is 800m 2 /g.
  • the flame-retardant aluminum hydroxide powder produced by Yangzhou Dilan Chemical Materials Co., Ltd. is used.
  • the effective content of the aluminum hydroxide is more than 99.6% by weight, and the attached water content is less than 0.8% by weight.
  • the black opaque polyimide film is adopted, the light transmittance is less than 1%, the heat shrinkage rate is less than 0.1%, and the moisture absorption rate is less than 2%.
  • polyphenylene sulfide fiber with an LOI value of 34% and 40% by weight of pre-oxidized fiber are used for blending, carding, and netting, and then needling processing at a needling density of 400 needles/cm 2 .
  • a needle-punched non-woven fabric with a thickness of 1.0 mm, a weight of 300 g/cm 3 and a bulk density of 0.30 g/cm 3 was prepared as a fiber structure, and the thermal conductivity of the fiber structure was measured to be 0.037W/(m ⁇ K), the pores in the fiber structure with a pore diameter between 5-50 ⁇ m account for 85% of the total pores; the needle punched non-woven fabric prepared above is immersed in the uniformly dispersed aerogel dispersion, and then the gas is fully absorbed
  • the fibrous structure after the gel dispersion is slightly pressurized to remove the excess dispersion on the surface, and then dried at low temperature to obtain an aerogel powder with an average diameter of 50 microns attached to the inside and surface of the needle punched non-woven fabric
  • the composite material is used as the heat insulation layer, and the weight ratio of the aerogel powder is measured to be 17%; after mixing the aluminum hydroxide powder and the polyethylene hot melt adhesive particles, the mixed particles are evenly spread in the above
  • a needle-punched non-woven fabric with a thickness of 1.5 mm, a grammage of 300 g/cm 3 and a bulk density of 0.20 g/cm 3 was prepared as a fiber structure, and the thermal conductivity of the fiber structure was measured to be 0.035W/(m ⁇ K), the pores in the fiber structure with a pore diameter between 5-50 ⁇ m account for 60% of the total pores; the needle punched non-woven fabric prepared above is immersed in a uniformly dispersed aerogel dispersion, and then the gas is fully absorbed
  • the fibrous structure after the gel dispersion is slightly pressurized to remove the excess dispersion on the surface, and then dried at low temperature to obtain an aerogel powder with an average diameter of 50 microns attached to the inside and surface of the needle punched non-woven fabric
  • the composite material is used as the thermal insulation layer, and the weight ratio of the aerogel powder measured is 24%.
  • the rest is the same as in Example 1, and finally the heat insulation and fireproof material of the present invention is prepared,
  • the fibrous structure after the gel dispersion is slightly pressurized to remove the excess dispersion on the surface, and then dried at low temperature to obtain an aerogel powder with an average diameter of 50 microns attached to the inside and surface of the needle punched non-woven fabric
  • the composite material is used as the thermal insulation layer, and the weight ratio of the aerogel powder is measured to be 43%.
  • the rest is the same as in Example 1, and finally the heat insulation and fireproof material of the present invention is prepared, and its physical properties are evaluated and shown in Table 1.
  • the layer is the heat storage layer; a polyimide film with an airtightness of 0.1cm 3 /cm 2 /s and a thickness of 80 microns is used to encapsulate from six sides, and the sealing material is fixed on the partition by heating and pressing.
  • the outer surface of the thermal layer was the same as in Example 1.
  • the heat insulation and fireproof material was finally prepared, and its physical properties were evaluated and shown in Table 1.
  • the heat storage layer is an integrated heat-insulating and fireproof material. At this time, the heat storage layer is the sealing layer. The rest is the same as in Example 2. The physical properties were evaluated and shown in Table 1.
  • the preparation method of the composite material is the same Example 2.
  • a polyimide film with an airtightness of 0.5cm 3 /cm 2 /s and a thickness of 50 microns is used to encapsulate from six sides, and the sealing material is fixed on the outer surface of the heat insulation layer by heating and pressing, and the final manufacturing
  • the heat insulating and fireproof material of the present invention was obtained, and its physical properties were evaluated and shown in Table 1.
  • polyphenylene sulfide fiber with an LOI value of 34% and 40% by weight of pre-oxidized fiber are used for blending, carding, and netting, and then needling processing at a needling density of 400 needles/cm 2 .
  • a needle-punched non-woven fabric with a thickness of 1.0 mm, a weight of 300 g/cm 3 and a bulk density of 0.30 g/cm 3 was prepared as a fiber structure, and the thermal conductivity of the fiber structure was measured to be 0.037W/(m ⁇ K), the pores in the fiber structure with pore diameters between 5-50 ⁇ m account for 85% of the total pores; the needle punched non-woven fabric prepared above is immersed in the uniformly dispersed hollow glass microbead dispersion, and then fully absorbed
  • the composite material on the surface and the surface is used as the heat insulation layer, and the weight ratio of the hollow glass microbead powder is measured to be 17%; after mixing the magnesium hydroxide powder and the poly
  • the sodium sulfate decahydrate powder and polyethylene hot melt adhesive particles After mixing the sodium sulfate decahydrate powder and polyethylene hot melt adhesive particles, the mixed particles are evenly spread on the upper and lower sides of the above-prepared heat insulation layer by sprinkling in to form a layer of decahydrate in the form of a film
  • the sodium sulfate powder layer is the heat storage layer; a polyimide film with an air tightness of 0.5cm 3 /cm 2 /s and a thickness of 50 microns is used for four-sided packaging from the upper and lower surfaces and the front and rear sides.
  • the sealing material was fixed on the outer surface of the heat insulation layer by heating and pressing. The rest was the same as in Example 9.
  • the heat insulation and fire protection material was finally prepared, and its physical properties were evaluated and shown in Table 1.
  • the needle punched non-woven fabric prepared in Example 1 was immersed in the evenly dispersed aerogel dispersion, and then the fiber structure after fully absorbing the aerogel dispersion was slightly pressurized to disperse the excess surface The liquid was removed and then dried at low temperature to obtain a composite material with an average diameter of 500 microns aerogel powder attached to the inside and surface of the needle punched non-woven fabric as a heat insulation layer. The weight ratio of the aerogel powder was measured to be 17%. The rest is the same as in Example 1, and finally the heat insulation and fireproof material of the present invention is prepared, and its physical properties are evaluated and shown in Table 2.
  • Example 2 The needle punched non-woven fabric prepared in Example 1 was immersed in the evenly dispersed aerogel dispersion, and then the fiber structure after fully absorbing the aerogel dispersion was slightly pressurized to disperse the excess surface The liquid was removed and then dried at low temperature to obtain a composite material with an average diameter of 1000 microns aerogel powder attached to the inside and surface of the needle punched non-woven fabric as a heat insulation layer. The weight ratio of the aerogel powder was measured to be 17%. The rest is the same as in Example 1, and finally the heat insulation and fireproof material of the present invention is prepared, and its physical properties are evaluated and shown in Table 2.
  • the needle punched non-woven fabric prepared in Example 1 was immersed in the evenly dispersed aerogel dispersion, and then the fiber structure after fully absorbing the aerogel dispersion was slightly pressurized to disperse the excess surface The liquid was removed and then dried at low temperature to obtain a composite material with an aerogel powder with an average diameter of 50 microns attached to the inside and surface of the needle punched non-woven fabric as a heat insulation layer. The weight ratio of the aerogel powder was measured to be 12%. The rest is the same as in Example 1, and finally the heat insulation and fireproof material of the present invention is prepared, and its physical properties are evaluated and shown in Table 2.
  • a warp-knitted spacer fabric with a thickness of 1.9mm, a weight of 420g/cm 3 and a bulk density of 0.22g/cm 3 is prepared as the fiber structure, and the fiber is measured
  • the thermal conductivity of the structure is 0.042W/(m ⁇ K), and the pores in the fiber structure with a diameter of 5-50 ⁇ m account for 58% of the total pores;
  • the warp-knitted spacer fabric prepared above is immersed in a uniformly dispersed aerosol
  • the fiber structure after fully absorbing the aerogel dispersion liquid is slightly pressurized to remove the excess dispersion liquid on the surface, and then dried at low temperature to obtain an aerogel powder with an average diameter of 50 microns
  • the composite material attached to the interior and surface of the warp-knitted spacer fabric is used as a thermal insulation layer, and the weight ratio of the aerogel powder is measured to be 25%.
  • a polyimide film with an airtightness of 0.5cm 3 /cm 2 /s and a thickness of 50 microns is used to encapsulate from six sides, and the sealing material is fixed on the outer surface of the heat insulation layer by heating and pressing, and the final manufacturing
  • the heat-insulating and fire-resistant materials were obtained, and their physical properties were evaluated and shown in Table 2.
  • the preparation method of the thermal insulation layer is the same as in Example 1.
  • the thermal insulation layer obtained is the thermal insulation and fireproof material of the present invention, and its physical properties are evaluated and shown in Table 2.
  • the heat insulation and fireproof materials prepared in Examples 1-18 were applied to power batteries.
  • a needle-punched non-woven fabric with a thickness of 0.6mm, a grammage of 300g/cm 3 and a bulk density of 0.50g/cm 3 was prepared as a fiber structure, and the thermal conductivity of the fiber structure was measured to be 0.051W/(m ⁇ K), the pores in the fiber structure with pore diameters between 5-50 ⁇ m account for 96% of the total pores; the needle punched non-woven fabric prepared above is immersed in a uniformly dispersed aerogel dispersion, and then the gas is fully absorbed The fibrous structure after the gel dispersion is slightly pressurized to remove the excess dispersion on the surface, and then dried at low temperature to obtain an aerogel powder with an average diameter of 50 microns attached to the inside and surface of the needle punched non-woven fabric The composite material is used as the thermal insulation layer, and the weight ratio of the aerogel powder is measured to be 5%. The rest is the same as in Example 1. The physical properties of this material were evaluated and shown in Table 3.
  • the needle-punched non-woven fabric prepared in Example 9 was immersed in the evenly dispersed hollow glass microbead dispersion, and then the fiber structure after fully absorbing the hollow glass microbead dispersion was slightly pressurized to remove the excess surface The dispersion liquid is removed, and then dried at low temperature to obtain a composite material of hollow glass microsphere powder with an average diameter of 1500 microns attached to the inside and surface of the needle-punched non-woven fabric as a heat insulation layer. The weight ratio of the hollow glass microsphere powder is measured Is 17%. The rest is the same as in Example 9. The physical properties of this material were evaluated and shown in Table 3.
  • the aerogel powder with an average diameter of 50 microns was piled into a 1.4mm thick rectangular parallelepiped and fixed in a bag made of a polyimide film with an airtightness of 0.5 cm 3 /cm 2 /s and a thickness of 50 microns.
  • the rest is the same as in Example 1, and finally a heat-insulating and fire-proof material is prepared, and its physical properties are evaluated and shown in Table 3.
  • a needle-punched non-woven fabric with a thickness of 1.0 mm, a weight of 300 g/cm 3 and a bulk density of 0.30 g/cm 3 was prepared as a fiber structure, and the thermal conductivity of the fiber structure was measured to be 0.037W/(m ⁇ K).
  • the pores in the fiber structure with a pore diameter between 5 and 50 ⁇ m account for 85% of the total pores.
  • the needle punched non-woven fabric prepared above is used as the heat insulation layer; the preparation methods of the heat storage layer and the sealing layer are the same as those in the embodiment 1.
  • the heat insulation and fireproof material was finally prepared, and its physical properties were evaluated and shown in Table 3.
  • Example 5 It can be seen from Example 5 and Example 7 that under the same conditions, the ratio of the average total thickness of the sealing layer of the latter to the total thickness of the heat-insulating and fire-resistant material is within a further preferred range. Compared with the former, the resulting heat-insulating and fire-resistant The material has good heat insulation.
  • Example 4 From Example 1 and Example 4, it can be seen that under the same conditions, the ratio of the average thickness of the heat storage layer to the average thickness of the heat insulation layer of the former is within a more preferable range.
  • the material has good heat insulation.
  • Example 1 It can be seen from Example 1 and Example 14 that under the same conditions, the aerogel weight ratio of the former is within the preferred range, and compared with the latter, the obtained heat insulating and fireproof material has better heat insulating properties.
  • Example 15 and Example 16 It can be seen from Example 15 and Example 16 that, under the same conditions, the proportion of the pore size of the fibrous structure of the latter is within the preferred range. Compared with the former, the obtained heat insulating and fireproof material has better heat insulating properties.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Secondary Cells (AREA)
  • Laminated Bodies (AREA)
  • Thermal Insulation (AREA)

Abstract

本发明公开一种隔热防火材料及其用途，所述隔热防火材料中至少含有隔热层，所述隔热层中含有多孔质材料和中空微粒，所述多孔质材料的体积密度为0.05～0.30g/cm 3，所述中空微粒的平均直径为30～1000μm，所述隔热防火材料经过碳化处理后的常温导热系数为0.040W/(m·K)以下。本发明的隔热防火材料具有阻燃性好、耐高温、导热系数小且轻量化的特点，可应用于动力电池的电芯之间。

Description

一种隔热防火材料及其用途 技术领域
本发明涉及一种隔热防火材料及其用途。
背景技术
在传统的电动汽车的动力电池中，隔热防火材料一般都是由耐高温阻燃无机材料形成的，如耐高温阻燃无机材料为云母材料。然而，由于云母的比重较大，在实际使用时，作为隔热片用于两枚电芯中间时，导致电池的整体重量增加，不利于电动汽车的轻量化，从而影响电动汽车的续航里程。
虽然在一定范围内增加电池数量可以提高电动汽车的续航里程，但是由于车内体积有限，并且重量也会随之增加，电池数量受到制约。为了可以达到增加续航里程的目的，在体积与重量不变的条件下，增加电池容量，即提高电池的能量密度。然而，提高电动车电池能量密度是比较困难的。
另外，云母片硬度高且发脆，在其厚度方向上极难被压缩。当电池在使用或充电过程中，电芯在厚度方向发生膨胀时，云母片被挤压却难以被压缩。虽然云母材料具有较好的耐热性，但是导热性能较差。因此，有必要开发出一种既有隔热防火效果，又有良好的压缩回弹性，即使在温度影响下，也可以承受因电芯发生的形变所带来的尺寸变化。
如日本公开专利特開2018-179010中公开了一种耐火隔热片材，该发明由于是将层积状隔热体放于耐火纤维制成的袋体中，在使用过程中受外力会发生振动或压缩的现象，在剪切作用下，隔热体与袋体会产生分离，无法保证整体片材可以发挥隔热作用。此外，无机纤维表面光滑、刚硬，构成无纺布的纤维之间的缠结力较小，气凝胶的附着也不稳定，导致隔热体整体的机械性能差，而且无机纤维本身密度大，难以屈曲，形成的无纺布克重高、厚度大，从而导致耐火隔热片材整体重量大、体积大，无法实现轻量化。另外，隔热体中虽然使用含有羟基的二氧化硅系无机纤维，通过加热的方法，Si(OH) 4发生脱水缩合反应生成H 2O，但是由于反应生成的水分非常有限，无法获得显著的吸热降温效果。
如日本公开专利特開2018-118489中公开了一种气凝胶层积复合体及隔热材料，由于该发明中的气凝胶单独呈层状分布，缺少起到支撑增强作用的基材，因此在受外力挤压时，极易被压缩变形，且外力去除后，被压缩部分也无法恢复。
如中国公开专利CN207425974U中公开了一种电池箱热失控阻断防护片，该实用新型由于纤维毡四周的高分子膜层贴合强度较低，在汽车行驶时电芯发生震动，并与阻燃绝热毡发生摩擦，导致高分子膜层的边缘发生剥离，其中的气凝胶粉末飞散，从而导致防护片的隔热性能下降。另外，该防护片材中还包括由金属材料制得的防爆层作为封装层，导致防护片材整体的重量增加，难于实现轻量化。
又如中国公开专利CN108689678A中公开了一种表面无气凝胶大颗粒附着的纤维增强气凝胶毡及其制备方法，该发明中纤维毡整体比重小、孔隙大且多，气凝胶颗粒难以附着，即使附着后，气凝胶颗粒也容易发生脱落，从而影响材料的隔热性能。而且，该发明中采用整卷常压浸胶方式，会导致气凝胶在卷状纤维毡中的分散均匀性不好，外层与内层的浸胶量不均匀，从而影响毡的隔热性能的稳定性。
发明内容
本发明的目的在于提供一种阻燃性好、耐高温、导热系数小且轻量化的隔热防火材料。
本发明的技术解决方案如下：本发明的隔热防火材料中至少含有隔热层，所述隔热层中含有多孔质材料和中空微粒，所述多孔质材料的体积密度为0.05～0.30g/cm 3，所述中空微粒的平均直径为30～1000μm，所述隔热防火材料经过碳化处理后的常温导热系数为0.040W/(m·K)以下。
上述隔热防火材料中还含有密封层，所述密封层为连续片状材料，所述密封层位于隔热层的至少相对两面，所述密封层的平均总厚度占隔热防火材料整体厚度的比例优选为0.5～90％。
上述隔热防火材料中还含有蓄热材料，所述蓄热材料为水合物或金属的氢氧化物，所述蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例优选为2.0～25.0％。
上述蓄热材料优选为层状结构分布于隔热层相对两侧，所述蓄热层的平均厚度与隔热层的平均厚度的比例优选为10～90％。
上述蓄热材料优选分散于隔热层中。
上述蓄热材料优选分散于密封层中。
上述多孔质材料优选为纤维构造体。
上述纤维构造体中孔径在5～50μm之间的孔优选占全部孔的50％以上。
在常温下，上述纤维构造体的导热系数优选低于0.040W/(m·K)。
上述纤维构造体优选为含有LOI值在28％以上的热塑性纤维与非熔融纤维形成的无纺布。
上述中空微粒优选为气凝胶粉末。
本发明的隔热防火材料中气凝胶粉末的重量比优选为15％以上。
上述连续片状材料的气密性优选在20cm 3/cm 2/s以下。
上述连续片状材料优选为膜状材料、由纤维纺织品形成的片材或由连续树脂形成的片状材料。
本发明的隔热防火材料的两面温度差优选大于300℃。
本发明的有益效果：本发明的隔热防火材料具有优异的隔热性与防火性，且轻量化的特点。本发明的隔热防火材料作为缓冲隔热材料可应用于动力电池的电芯之间，可以有效阻隔热能传递，并且防火阻燃，减缓电芯爆炸时的巨大热量与火焰的传递速度，缓慢地将热量传导到相邻的电芯，从而延长驾乘人员的逃生时间，起到安全防护的作用。
附图说明
图1为本发明隔热防火材料的示意图，图中，A为隔热层、B为蓄热层、C为密封层，蓄热层B分布在隔热层A的两侧，其中，a为多孔质材料、b为中空微粒、c为连续片状材料、d为蓄热材料。
图2为本发明隔热防火材料的示意图，图中，A为隔热层、B为蓄热层、C为密封层，蓄热层与密封层为同一层，其中，a为多孔质材料、b为中空微粒、c为连续片状材料、d为蓄热材料。
图3为本发明隔热防火材料的示意图，图中，A为隔热层、B为蓄热层、C为密封层，隔热层与蓄热层为同一层，其中，a为多孔质材料、b为中空微粒、c为连续片状材料、d为蓄热材料。
具体实施方式
本发明的隔热防火材料中至少含有隔热层，所述隔热层中含有多孔质材料和中空微粒，所述多孔质材料的体积密度为0.05～0.30g/cm 3，所述中空微粒的平均直径为30～1000μm，所述隔热防火材料经过碳化处理后的常温导热系数为0.040W/(m·K)以下。多孔质材料是指由相互贯通或封闭的孔洞构成网状结构的材料，该材料具有一定的厚度， 如多孔质材料为泡沫多孔材料、金属粉末烧结多孔材料、纤维构造体等，优选纤维构造体，因为纤维构造体具有较好的压缩回复性，受外力发生压缩形变，随着外力去除后，纤维构造体能够较快回复，消除压缩形变。中空微粒是指具有中空结构或空腔的微粒颗粒物，其中的空腔可以是全部封闭，也可以是部分封闭。如中空微粒为中空二氧化硅微粒、中空玻璃微珠、中空陶瓷微粒等，优选中空二氧化硅微粒，即二氧化硅气凝胶微粒，因为中空二氧化硅微粒具有高孔隙率、高比表面积、且轻质的特点，具有优异的隔热性能。适当粒径的二氧化硅气凝胶粉体保持了气凝胶的纳米孔结构，更容易分散、填装，然后与多孔质材料进行复合，即中空微粒可以有效地容纳、附着在含孔洞构成网状结构的多孔质材料上，多孔质材料给予中空微粒支撑，使之成为一体形成隔热层，所得的隔热层具有一定的机械强力以及功能性，比如防火、隔热等。
本发明的多孔质材料的体积密度必须控制在一定的范围内，如果多孔质材料的体积密度低于0.05g/cm 3的话，该材料内孔隙过多，甚至出现较大的贯穿型孔洞，附着在多孔质材料上的中空微粒就会从大孔中掉落出来，甚至无法蓄积中空微粒，所得的隔热层起不到隔热的效果；如果多孔质材料的体积密度高于0.30g/cm 3的话，多孔质材料变得致密，多孔质材料中的孔隙变小、变少，中空微粒的附着量降低，甚至无法进入多孔质材料的内部，使得隔热层的隔热性能大大下降。中空微粒由于具有中空或空腔结构，能够贮存空气，合适粒径的中空微粒附着、蓄积于多孔质材料中，可以大大降低本发明隔热防火材料对热量传递的阻隔性，如果中空微粒的平均直径小于30μm的话，分散在多孔质材料中的中空微粒与多孔质材料的接触面积变小，导致中空材料附着困难，极易发生飞散、掉落的现象，从而引起隔热性能下降；如果中空微粒的平均直径大于1000μm的话，大颗粒的中空微粒难以进入多孔质材料的内部孔隙中，而只是仅仅浮于多孔质材料的表层，使用时极易飞散、掉落，隔热性能大幅度下降，而且由于中空微粒粒径过大，中空微粒在多孔质材料中的分散变得极为不均匀，从而导致材料整体的隔热性能均匀性变差。考虑到中空微粒的分散稳定性与隔热性能均匀性，中空微粒的平均直径优选为50～800μm，更优选50～500μm。这里的中空微粒的平均直径，对于气凝胶微粒而言，该粒径是指由气凝胶的三维空间网状结构所构成的集合体的粒径。
本发明的隔热防火材料经过碳化处理后的常温导热系数为0.040W/(m·K)以下。作为用于电芯间的隔热材料，可以有效延缓或阻断电芯的热失控，从而延缓向整个电池系统热传递的时间，因此隔热防火材料必须具备优异的隔热性，特别是受电芯热失控时隔热防火材料会瞬间受高温发生碳化，此时更要求隔热防火材料在碳化后仍保持良好的隔热性能，从而避免连锁失控。如果隔热防火材料经过碳化处理后的常温导热系数高于0.040W/(m·K)的话，即当隔热材料受高温时发生碳化，其导热系数变高，发生热失控的电芯所产生的高温无法被阻隔，发生热扩散反应，引起热量快速传递，进一步迅速将热传导传到相邻的电芯，使相邻的电芯瞬间发生连锁热失控，进一步加剧了电池燃烧速度，减少了驾乘人员宝贵的逃生时间，甚至会导致严重的伤亡事故发生。考虑到隔热防火材料中多孔质材料的体积密度以及中空微粒的含有量，本发明隔热防火材料经过碳化处理后的常温导热系数优选为0.020～0.040W/(m·K)。
本发明的隔热防火材料中优选为含有密封层，所述密封层为连续片状材料，所述密封层位于隔热层的至少相对两面，所述密封层的平均总厚度占隔热防火材料整体厚度的比例优选为0.5～90％。由于隔热层中多孔质材料上附着有中空微粒，在隔热材料包装、运输、使用过程中，中空微粒受到外力作用容易出现飞散、掉落等情况，直接影响到该材料的隔热性能，当该材料被应用于电芯之间作为隔热缓冲材时，隔热性变差或不均匀，一旦出现电芯异常升温，就无法及时有效地阻断热量的传递，从而导致电芯发生热失控，严重时会造成驾乘人员来不及逃离，引发重大伤亡事故。因此，优选在隔热层的至少相 对两面设置密封层，该密封层为连续片状材料，这样可以有效防止隔热层中的中空微粒飞散，最大程度保持隔热性能。由于隔热层是具有一定厚度的材料，可以将它视为一个长方体。因此，密封层可以位于隔热层的相对两面，也可以位于隔热层的四面或六面，当密封层位于隔热层的相对两面时，该两面是长方体的隔热层上所占面积最大的相对两面，即隔热层的上、下两个表面，这样既可以起到防止隔热层中的中空微粒受外力振动或挤压而飞散、脱落的发生，也可以快速、低成本地生产；当密封层位于隔热层的四面或六面时，即密封层不仅覆盖于隔热层的上、下两个表面，还覆盖于隔热层的侧面，此时，可以完全防止隔热层中的中空微粒受外力振动或挤压而发生飞散、脱落的发生，因此更优选密封层位于隔热层的四面或六面。
当密封层为膜状材料时，密封层的平均厚度优选5～200μm。如果膜状材料的平均厚度过薄的话，受两侧电芯之间的热膨胀挤压和摩擦，容易发生破损，导致隔热层中的中空微粒飞散、掉落，引起隔热性下降；如果膜状材料的平均厚度过厚的话，由于密度较高，可压缩空间过小，且即使被压缩后，其回弹性较差，当电芯冷却恢复原有厚度时，隔热防火材整体上无法回复到原有厚度，导致相邻电芯之间出现空隙，隔热防火材发生松动。
当密封层为纤维纺织品时，密封层的平均厚度优选100～400μm。如果纤维纺织品的厚度过薄的话，受两侧电芯之间的热膨胀挤压和摩擦，容易发生破损，导致隔热层中的中空微粒飞散、掉落，引起隔热性下降；如果纤维纺织品的厚度过厚的话，由于隔热防火材整体厚度有一定限制，一般不超过4mm，这样隔热层厚度或蓄热层厚度只能减少，导致隔热防火材整体的性能下降。特别是优选厚度在100～200μm的高密度阻燃纤维纺织品作为密封层，不仅能防止隔热层中的中空微粒飞散、掉落，还可以提高隔热防火材料的抗形变、抗剪切强力，甚至还起到阻燃防火的作用，在电芯发生着火时，可以阻挡火焰蔓延，减缓热量传递。
当密封层为树脂形成的片状材料时，由于在树脂形成的片状材料中含有蓄热材料，当所含有的蓄热材料越多，所在树脂形成的片状材料厚度也就越高。对于隔热防火材来说，对热量的吸收也就越多。考虑到隔热防火材的整体厚度，密封层的平均厚度优选200～1000μm。如果树脂形成的片状材料的厚度过薄的话，由于树脂层中所含有的蓄热材料过少，能够吸收的热量变少，导致隔热防火材整体的隔热性下降；如果树脂形成的片状材料的厚度过厚的话，由于隔热防火材整体厚度有一定限制，一般不超过4mm，这样隔热层厚度变薄，隔热性能下降，也会导致隔热防火材整体的隔热性能下降。
上述密封层的平均总厚度占隔热防火材料整体厚度的比例优选为0.5～90.0％，本发明中密封层的平均总厚度是指分布于隔热层的上、下两个表面的平均厚度的总和，隔热防火材料整体厚度是指本发明的隔热防火材料的上、下两个表面之间的距离，即包括了隔热层、蓄热层以及密封层的所有厚度。密封层的平均总厚度与隔热防火材料整体厚度的比值，一方面可以反映出密封层对中空材料的密封性能，另一方面也直接影响到隔热防火材料整体的压缩回复性能。如果密封层的平均总厚度占隔热防火材料整体厚度的比例过低的话，说明密封层过薄，当所得的隔热防火材料安装在电芯之间时，受两侧电芯振动以及产生的摩擦力，容易将过薄的密封层的连续状态破坏，从而导致均匀分散在多孔质材料内部的中空微粒因振动等外力发生掉落，中空微粒从多孔质材料的孔隙中散落出来，造成中空微粒的附着量变少，分布不均匀，当电芯发生热失控时无法起到很好的隔热防火效果，导致热量迅速传导到相邻的电芯引起连锁反应；如果密封层的平均总厚度占隔热防火材料整体厚度的比例过高的话，说明密封层过厚，当所得的隔热防火材料安装在电芯之间时，受到两侧热膨胀的电芯挤压，过厚的密封层由于密度较高，可压缩空间过小，并且即使被压缩后，其回弹性较差，当电芯冷却恢复原有厚度时，隔热防 火材料在整体上无法回复到原有的厚度，导致出现空隙，导致电芯松动，甚至电芯变形失效。另一方面，密封层的平均总厚度占隔热防火材料整体厚度的比例过高的话，即隔热层的厚度过薄，作为隔热主体的隔热层中多孔质材料与中空微粒过少，无法为材料提供足够的隔热性能，制得的隔热防火材料安装在电芯之间时，在电芯发生热失控时无法起到很好的隔热防火效果，导致热量很快传导到相邻电芯引起连锁反应。考虑到隔热防火材料的隔热防火、缓冲减震、以及轻量化等性能要求以及被应用于电芯之间时的密封性、压缩回弹性，本发明密封层的平均总厚度占隔热防火材料整体厚度的比例更优选10.0～70.0％，进一步优选25.0～50.0％。
本发明的隔热防火材料中优选含有蓄热材料，蓄热材料可以弥补本隔热防火材料中单纯的隔热层对热量阻隔作用的局限性，特别是隔热防火材料处于温度急剧上升的环境下，蓄热材料可以有效抑制温度上升。所述蓄热材料为水合物或金属的氢氧化物，所述蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例优选为2.0～25.0％。水合物指的是含有水的化合物，通常指结晶水合物，即含有一定量结晶水的物质，其来源相当广泛。水合物中的水可以以配位键与其他部分相连，如水合金属离子，化学式为KAl(SO 4) 2·12H 2O，也可以是以共价键相结合，如水合三氯乙醛。有的结晶水合物在室温和干燥的空气里,能自动失去部分或全部结晶水,这种现象被称为风化，因而此类结晶水合物在常温下就因为失去水分而不存在，也有的结晶水合物需要在一定的加热条件下才发生，水合物被加热时会发生水解反应或脱水反应，即水分子被加热失去。水分子的失去可以发生在化合物分子内部，即分子内脱水，也可以发生在同一化合物的两个分子之间，即分子间脱水。脱水过程中水合物的水发生吸热反应，能够吸收热量，从而可以起到减少热量传导的作用。金属的氢氧化物是指金属阳离子与氢氧根离子(-OH)形成的无机化合物，受热时能生成金属氧化物和水，可以吸收热量。由于金属氢氧化物的分解温度差异很大，如Al(OH) 3的热分解起始温度约220℃，Mg(OH) 2的热分解起始温度约340℃，而NaOH很难被加热分解。这与金属氢氧化物中金属的金属性有关，一般来说金属性越强，氢氧化物的稳定性越高。考虑到本发明的隔热防火材料的实际应用环境，优选分解温度在100～1200℃的金属氢氧化物，如氢氧化钙、氢氧化镁、氢氧化铝等。此外，从蓄热密度的角度出发，不仅优选分解温度在100～1200℃范围内的，进一步优选蓄热密度在600kJ/kg以上的金属氢氧化物，比如氢氧化铝。这里的蓄热密度可以表征单位重量的材料吸收热量多少的能力，如果蓄热材料的蓄热密度过低的话，在接触温度急剧上升的电芯时将无法吸收其产生的大量热量，蓄热材料迅速吸热达到饱和，不再吸热，无法有效延缓电芯温度的升高，从而影响材料的整体隔热性能。考虑到复合加工后样品的整体质量及隔热性能，化学蓄热材料的蓄热密度更优选为1000kJ/kg以上。
上述蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例优选为2.0～25.0％，如果所述蓄热材料受热分解时释放出的水分重量相对于隔热防火材料的重量比例过低的话，其受热后所释放出来的水分能够吸收的热量较小，也就是在较低热量条件下就能发生热分解，然而，当此类蓄热材料被应用于电芯之间时，如果电芯异常发热引起热失控的话，蓄热材料接触温度急剧上升的电芯时，就不能快速吸收电芯产生的大量热能，从而无法有效阻隔热量向相邻电芯传递，严重时发生连锁爆炸；如果蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例过高的话，作为隔热主体的隔热层，其重量比例必定下降，也就是隔热层中的多孔质材料与中空微粒的重量比例下降，直接导致隔热防火材整体的隔热性能降低，从而无法提供足够的隔热性能，制得的隔热防火材料安装在电芯之间时，隔热效果差，导致较多热量快速传导到相邻电芯，发生连锁反应，导致电池整体发生热失控。考虑到隔热防火材料整体的隔热性与轻量化， 上述蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例更优选为5～20％。
本发明的隔热防火材料中优选含有蓄热材料，蓄热材料通过以下方式存在于隔热防火材料中。
方法一：将蓄热材料与可热熔融的固态难燃粘合剂颗粒进行混合得到混合颗粒，将混合颗粒以铺撒的方式均匀铺放在预先制备好的隔热层的上、下两面，以膜的形式形成一层蓄热粉末层，即为蓄热层，再使用连续片状材料进行至少相对两面的封装，通过加热熔融冷却固化的方式使两者初步固结，形成分布在隔热层两侧的蓄热层，并被连续片状材料封装为一体的隔热防火材料。
方法二：将蓄热材料与液态难燃树脂均匀混合，形成蓄热材料的难燃树脂液，然后将其均匀涂敷在预先制备好的隔热层的上、下两面，在适宜的温度下干燥固化后室温冷却，在隔热层两侧分别形成一层附着有蓄热材料粉末的难燃树脂固化膜，最终得到蓄热层分布在隔热层两侧的蓄热层与密封层为一体的隔热防火材料，此时，蓄热层即为密封层。上述制得的附着有蓄热材料颗粒的难燃树脂固化膜不仅能吸收大量的热量，又能解决多孔质材料内部的中空微粒从多孔质材料的孔隙中散落出来的问题。
方法三：将蓄热材料粉末撒进预先制备好的含有中空微粒的多孔质材料中，通过物理填充的方式使蓄热材料粉末充分进入到多孔质材料与中空微粒的空隙之间，制得隔热层，也是蓄热层，再使用连续片状材料进行至少相对两面的封装，形成隔热层与蓄热层为同一层结构，并被连续片状材料封装为一体的隔热防火材料。
本发明隔热防火材料的制备方法不局限以上三种，也可以将上述三种方法进行交叉使用，得到兼备隔热性与防火性，且轻量化的隔热防火材料。
本发明蓄热材料优选为层状结构分布于隔热层相对两侧，所述蓄热层的平均厚度与隔热层的平均厚度的比例优选为10～90％。蓄热层优选分布于隔热层相对两侧，由于隔热层具有一定厚度，可视作长方体。隔热层相对两侧是指长方体的隔热层中所占面积最大的相对两侧，即上、下两个表面。该隔热层的相对两侧直接与电芯发生面接触，当电芯一旦发生热失控时，能够最有效地阻隔来自电芯的热量，从而延缓相邻电芯发生热失控，避免引起连锁反应。如果蓄热层的平均厚度与隔热层的平均厚度的比例过低的话，即蓄热层的平均厚度所占比例过小，蓄热层中起蓄热作用的蓄热材料较少，受热分解时能吸收的热量也急剧降低，就起不到吸热及抑制温度上升的作用，而只能靠隔热层的隔热作用，从而不能充分地阻隔热传导，使得相邻电芯受热升温加剧发生热失控；如果蓄热层的平均厚度与隔热层的平均厚度的比例过高的话，即隔热层的平均厚度所占比例过小，隔热层的厚度过薄，作为隔热主体的隔热层中所含有的多孔质材料与中空微粒的含量也就过少，特别是中空微粒的含量减少后，多孔质材料中含有的贯通孔隙可能会被直接暴露，一侧的高温热量会通过该孔隙直接传递到对侧，无法有效阻隔热量。而且当隔热层的厚度过薄，也就是中空微粒所在层的厚度过薄，中空微粒能够形成的空气阻隔层变薄。众所周知，空气是绝好的隔热材料，当空气阻隔层变薄，直接导致对热的阻隔效果变差，也就是热量可以轻易地从隔热层的一侧传递到另一侧。当将制得的隔热防火材料安装在电芯之间时，在电芯发生热失控时，过薄的隔热层无法起到较好的隔热防火效果，导致热量很快传导到相邻电芯，引起连锁热失控反应。考虑到隔热防火材料的隔热防火、缓冲减震以及被应用于电芯之间时的密封性、压缩回弹性，上述蓄热层的平均厚度与隔热层的平均厚度的比例更优选为15～85％。
上述蓄热层的平均厚度优选为100～2000μm，当蓄热层为层状结构分布于隔热层相对两侧时，即每一侧蓄热层的厚度优选为50～1000μm。蓄热层中所含有的蓄热材料越多，形成的蓄热层也就越厚，对热量的吸收也就越多，但最终得到的隔热防火材的厚 度也就越高。考虑到隔热防火材的整体厚度，当蓄热材料与可热熔融的固态难燃粘合剂颗粒进行混合得到混合颗粒，并以铺撒的方式均匀铺放在预先制备好的隔热层的上、下两面时，此时一侧蓄热层的厚度更优选50～200μm。当蓄热材料分散于难燃树脂中，同时也作为密封层位于隔热层两侧时，此时一侧蓄热层的厚度优选200～1000μm。如果一侧蓄热层的厚度过薄的话，由于所含有的蓄热材料过少，在接触温度急剧上升的电芯时，将无法吸收其产生的大量热量，蓄热材料迅速饱和不再吸热，无法有效延缓相邻电芯温度的升高，导致隔热防火材整体的隔热性下降。
上述隔热层的平均厚度优选为600～2400μm。隔热层含有多孔质材料和中空微粒，在隔热防火材料中起到重要的隔热作用。如果隔热层厚度过薄的话，当该隔热防火材被应用于电芯之间作为隔热缓冲材时，一旦电芯在使用过程中出现异常升温，就无法及时有效地阻断热量的传递，从而导致电芯发生连续热失控，严重时会造成驾乘人员来不及逃离，引发重大伤亡事故；如果隔热层厚度过厚的话，就需要通过减少蓄热层或密封层的厚度来调整，蓄热层厚度减少后，在接触温度急剧上升的电芯时，无法吸收其瞬间产生的大量热能。
本发明优选蓄热材料分散于隔热层中。当通过上述方法三制得隔热防火材时，即将蓄热材料粉末撒进预先制备好的含有中空微粒的多孔质材料中，通过物理填充的方式使蓄热材料粉末充分进入到多孔质材料与中空微粒的空隙之间，制得隔热层，也是蓄热层，再使用连续片状材料进行至少相对两面的封装，形成隔热层与蓄热层为同一层结构，并被连续片状材料封装为一体的隔热防火材料。蓄热材分散于隔热层中，与中空微粒混合后，在接触高温物体时，能够同时发挥隔热与吸热的作用，较快阻隔热量的传递。
本发明优选蓄热材料分散于密封层中。当通过上述方法二制得隔热防火材时，即将蓄热材料与液态难燃树脂均匀混合，形成蓄热材料的难燃树脂液，然后将其均匀涂敷在预先制备好的隔热层的上、下两面，在适宜的温度下干燥固化后室温冷却，在隔热层两侧分别形成一层附着有蓄热材料粉末的难燃树脂固化膜，形成分布在隔热层两侧的蓄热层为一体的隔热防火材料，此时，蓄热层即为密封层。上述制得的附着有蓄热材料颗粒的难燃树脂固化膜不仅能吸收大量的热量，又能解决多孔质材料内部的中空微粒从多孔质材料的孔隙中散落出来的问题。蓄热材分散于密封层中，即分布在隔热层的至少相对两侧，通过调整密封层的厚度，可以精确控制蓄热材的使用量。在接触高温物体时，分散于外侧的蓄热材能够第一时间发生热分解吸收热量，减缓热传递。然后，隔热层进一步将热量阻隔，同时一部分热量继续传递到远离热源的蓄热层，蓄热层继续发生热分解吸收热量，隔热与吸热的作用得到最有效的发挥，从而保证隔热防火材具有优异的隔热性能。
本发明的多孔质材料优选为纤维构造体。纤维构造体是指由纤维形成的集合体，如无纺布等。其中，无纺布由于具备一定的厚度，且容易形成多孔结构，并具有一定的压缩回弹性能，作为支撑基材使用的话，具有良好的性能，因此作为优选。无纺布的形态可以是针刺、水刺等，考虑到与气凝胶材料进行复合加工，纤维构造体的形态更优选为具有多孔结构的针刺无纺布。作为针刺无纺布，其针刺密度优选在100针/cm 2以上，针刺密度更优选在150针/cm 2以上，所得纤维构造体中，纤维之间的缠结更多，摩擦力与抱合力更强，整体具有更高的拉伸强度，更高的剪切强度以及剪切模量。也就是形成无纺布的针刺密度尤为重要，如果针刺密度过低的话，无法保证必要的拉伸、剪切等机械性能；如果针刺密度过高的话，无纺布层被反复穿刺，不仅加工性能下降，材料整体所含的孔隙变少，中空微粒的附着量降低，还会引起构成该无纺布的纤维强度发生下降，反而引起剪切性能下降。具体来说，根据ASTM C 273/C 273M测试标准，本发明的隔热防火材料的剪切强度及剪切模量优选在1MPa以上。本发明的隔热防火材料是被应用 于电池中的，由于电池中两枚电芯之间的初始间隔是相对固定的，当电池在使用或充电过程中，会产生大量的热量，电芯受热发生膨胀，厚度就会增加，两枚电芯之间的间隔变窄。此时，纤维构造体可以提供较好的压缩回弹性能，能够吸收电芯鼓胀应力，起到缓冲作用，即本发明的纤维构造体在电芯受热膨胀时可以被压缩，而在电芯冷却收缩后，还能回复到原有的厚度。另外，作为用于电芯间的隔热防火材料，汽车在移动过程中，电芯不断发生振动和相对位移，并带动隔热防火材料发生摩擦剪切作用。因此，需要该隔热防火材料具有较好的剪切强度及剪切模量。
本发明纤维构造体中孔径在5～50μm之间的孔优选占全部孔的50％以上。纤维构造体中存在的孔状结构有利于气凝胶粉末的附着与固定，从而赋予纤维构造体更好的隔热性。如果纤维构造体中的孔过大，气凝胶粉末容易飞散，且分散的均匀性变差；如果纤维构造体中的孔过小，表面张力过大，则气凝胶粉末不易进入孔的内部，附着力变差，受外力振动时容易飞散掉落。如果纤维构造体中5～50μm之间的孔占全部孔的比率过低的话，复合加工时，分散在液体中的气凝胶粉末进入纤维构造体中的孔内，极易发生流动，并快速从纤维构造体中的孔中流出，导致气凝胶粉末无法均匀分散，隔热性能变差。考虑到气凝胶分散液进入显微构造体中的难易程度以及粉末的分散均匀性，上述纤维构造体中孔径在5～50μm之间的孔更优选占全部孔的50～95％。
在常温下，本发明的隔热防火层中纤维构造体的导热系数优选低于0.040W/(m·K)。作为电芯间的隔热材料，作为一种能够有效延缓或阻断电芯热失控，延缓向整个电池系统的传播的热防护材料，构成其主体的纤维构造体必须具备优异的隔热性。如果纤维构造体在常温下的导热系数过高的话，无法有效发挥隔热作用，抑制热扩散，也无法延缓火势蔓延，也有可能迅速将热传导到达相邻的电芯，引起热量快速传递，从而导致连锁热失控，减少了逃生的时间，从而导致事故发生。
上述纤维构造体优选为含有LOI值在28％以上的热塑性纤维与非熔融纤维形成的无纺布。LOI值在28％以上的热塑性纤维，包括但不限于阻燃聚酯类纤维、聚苯硫醚纤维、聚四氟乙烯纤维等。非熔融纤维包括但不限于预氧化纤维、玻璃纤维、酚醛纤维等，这里的非熔融纤维可以作为更耐热的骨架支撑层，使所得隔热阻燃材料保持一定的形状，能够承受形变。其中，热塑性纤维与非熔融纤维的比例为10％：90％～80％:20％。如果热塑性纤维与非熔融纤维的比例过低的话，说明热塑性纤维的含量过少，不足以均匀地覆盖在非熔融纤维的表面，当所得的隔热防火材料遇到高温时，从而无法全面有效地阻断大规模的热失控，该热失控是从失控单体电芯向周围电芯传播；如果热塑性纤维与非熔融纤维的比例过高的话，则该隔热防火材料遇到高温时，过量的热塑性纤维就会发生熔滴，而非熔融纤维过少，导致无法承载熔滴的热塑性纤维，从而制得的隔热防火材料会发生熔滴穿孔，导致热量或火焰快速直接地传向周围的电芯，引发大规模热失控，甚至会造成驾乘人员的伤亡。
本发明的中空微粒优选为气凝胶粉末。气凝胶粉末具有纳米多孔结构，密度极低，作为优异的保温隔热材料，被广泛用于管道、船舶、动车、电池中。然而，气凝胶的强度低、脆性大、力学性能差，若单独使用的话，无法发挥其隔热性。因此，将气凝胶粉末附着于纤维构造体表面，纤维构造体本身由纵横交错的纤维形成多孔结构。该多孔结构可以作为气凝胶粉末的附着基材，能够有效承载气凝胶粉末，从而实现本材料整体优异的隔热性。本发明的气凝胶粉末附着于纤维结构体表面的方法如下：先是将纤维构造体浸入均匀分散的气凝胶分散液中，分散于液体中的具有较小平均直径的气凝胶粉末进入相性较好的纤维构造体内部，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到气凝胶粉末附着于纤维 结构体表面复合材料，最后对该复合材料进行封装加工，从而解决了纤维构造体内部的气凝胶粉末从纤维构造体中的孔隙散落出来的问题。
本发明的隔热防火材料中气凝胶粉末的重量比优选为15％以上。如果气凝胶粉末的重量比过低的话，即气凝胶粉末在纤维构造体中的附着量变小，甚至纤维构造体内局部无气凝胶粉末附着，导致气凝胶粉末分散不均匀，从而影响材料的隔热性能的均匀性和稳定性，材料整体的隔热性也变差。考虑到加工成本与隔热性能，本发明的隔热防火材料中气凝胶粉末的重量比更优选为20～80％，进一步优选20～60％。
由于分散在多孔质材料中的中空微粒体积小、比重轻，在外力作用下容易洒落。为了防止因中空微粒的飞散、洒落而引起材料的隔热性能下降的问题，位于多孔质材料外侧的连续片状材料气密性优选在20cm 3/cm 2/s以下，更优选在15cm 3/cm 2/s以下，进一步优选在10cm 3/cm 2/s以下。气密性过高，则密封性变差，当隔热防火材料受外力挤压或冲击时，纤维构造体内部的气凝胶粉末容易飞散、掉落。气密性越低，气凝胶粉末越能够被封锁、固定于纤维构造体内，能够有效起到隔热作用，同时也有利于机械吸盘通过负压对材料进行搬送和装配。
上述连续片状材料优选为膜状材料、由纤维纺织品形成的片材或由连续树脂形成的片状材料。当连续片状材料为膜状材料时，有利于隔热防火材料整体的轻量化，该膜状材料的任意一侧还可以含有热反射材料。热反射材料可以是附着于膜状材料表面的热反射涂料，比如热蒸镀铝等，也可以是热反射连续片状材料，比如铝箔等。热反射材料对于减少热量传递，具有比较明显的阻热效果。该膜状材料可以为耐高温性较好的高分子薄膜，比如聚苯硫醚薄膜，聚酰亚胺薄膜等，也可以为常规的聚酯薄膜，还可以为非耐高温或非阻燃类型的薄膜，比如聚乙烯薄膜。为了整体的隔热防火材料具有优异的阻燃性，非耐高温或非阻燃类型的薄膜材料的克重优选在20g/m 2以下，更优选在15g/m 2以下。该膜状材料可以通过加热的方式发生部分熔融，然后与隔热层中的多孔质材料进行结合；该膜状材料也可以通过热熔胶粉末等粘结剂与隔热层中的多孔质材料进行结合。
当连续片状材料为由纤维纺织品形成的片材时，纤维纺织品更优选由阻燃纤维所构成的纺织品，例如芳纶织物。纤维纺织品形态不限，可以是机织物、编织物或无纺布。
当连续片状材料为由连续树脂形成的片状材料时，优选耐热性或阻燃性较好的涂层材料。比如，无机耐高温涂料中的陶瓷涂料、硅酸盐类涂料等，以及有机耐高温涂料中的氟树脂涂料、有机硅耐高温涂料等。
本发明的隔热防火材料的两面温度差优选大于300℃。即当隔热防火材料的一面与高温热源接触时，热量从温度较高的加热面开始向温度较低的非加热面进行传导，在发生热量传导20分钟后，两面的温度差会大于300℃。当位于隔热防火材料一面的电芯发生热失控时，其温度会快速升高，并将热量迅速传递到隔热防火材料的一侧表面。此时，为了避免电芯发生连锁热失控，隔热防火材料必须具有优异的隔热性能。在热量传递的数分钟之内，材料两面的温度差大于300℃时，可以有效减缓热量传递速度，从而为驾乘人员争取到宝贵的逃生时间。如果隔热防火材料的两面温度差过低的话，电芯升温时，热量会快速传导到相邻电芯，极短时间内引起连锁热失控，从而危及驾乘人员生命。
本发明的隔热防火材料的压缩弹性率为3～15％，锂离子动力电池在充放电时，电芯内部会出现一定的内压力以及变形。因此，放置在电芯间的隔热材料需要有一定的压缩变形以及压缩后的回复力。如果该隔热防火材料的刚性大，即压缩形变小，电池在充放电过程中，电芯内的内压力无法释放，导致电芯外壳受挤压发生变形，降低电池系统寿命以及安全性；如果隔热垫压缩后无法回复，则电芯之间的空隙会变大，行驶时会发生电芯松动、碰撞的现象，导致热失控的概率上升，安全性大幅降低。
本发明的隔热防火材料通过将中空微粒与多孔质材料进行复合加工得到隔热层，并对隔热层进行封装，有效防止中空微粒的飞散、掉落，实现了隔热性与防火性兼备，且轻量化的电芯隔热缓冲材料，该隔热防火材料可应用于电池中。
通过以下实施例对本发明作进一步说明，但本发明的保护范围并不限于实施例，实施例中的各物性参数由下面方法测定。
【体积密度】
体积密度是指材料的质量与物质、闭气孔和开气孔体积之和的比值,单位是g/cm 3。对于具有一定厚度的多孔质材料来说，分别测定该多孔质材料的单位面积重量和厚度，再通过以下公式计算，即可得到该多孔质材料的体积密度。单位面积重量的测试方法：根据JIS L 1096～1999 8.4，使用电子天平，称取10cm×10cm的试样的重量，然后将所得数据乘100，得到换算后每平方米织物的重量，测定5组数据，取5次测试结果的平均值作为该样品的最终测试结果；厚度的测试方法：根据JIS L 1096～1999 8.5，采用手持式厚度仪，测试样品的厚度，测定5组数据，取5次测试结果的平均值作为该样品的最终测试结果。体积密度的计算公式如下：
体积密度(g/cm 3)＝单位面积重量(g/m 2)/厚度(mm)/1000。
当多孔质材料表面贴合有密封材料或内部含有中空微粒及其他颗粒物时，先将表层的密封材料剥离之后，再使用与中空微粒或其他颗粒物亲和性较高的溶剂去除中空微粒或其他颗粒物。可以选择以下材料作为溶剂，比如水、甲醇、乙醇、丙酮、正己烷、甲基丙酮等，可以使用其中一种，也可以多种组合使用，能够使多孔质材料不软化、不变形、不溶解的溶剂均可使用。
可以适当选择清洗温度和时间，但需要选择使多孔质材料不软化、不变形、不溶解的溶剂。另外，洗净可以是浸渍处理，也可以增加机械作用，例如超声波洗净之类的方法。
洗涤后进行干燥处理，选择使多孔质材料不软化、不变形、不熔化的温度和时间。第一次清洗、干燥后的多孔质材料的重量，测量标记为W 1。当第二次清洗、干燥后的多孔质材料的重量，测量标记为W 2，当(W 1-W 2)/W 1×100(％)的重量减少率在0.5％以下时，可以认为已经完全去除了中空微粒和其他颗粒物。再采用上述方法，测定多孔质材料的单位面积重量以及厚度，最后计算得到多孔质材料的体积密度。
【中空微粒的平均直径】
将中空微粒取样后固定于样品台上进行镀金处理，采用扫描电子显微镜(SEM)对中空微粒进行拍摄，拍摄倍率为1000倍，测定50个样本的中空微粒的直径，取该50次的测试结果，计算其平均值，作为该中空微粒的平均直径。
【碳化处理】
在室内常温有氧环境下，对隔热防火材料在温度为600℃下进行平板加热处理，单面处理15分钟后，再对另一面进行加热处理15分钟后，停止加热，取下被处理样品，碳化处理完成。
【导热系数】
根据GB/T 10295～2008测试标准，在25℃时，测定隔热防火材料的导热系数。
【LOI值】
根据ISO4589-2-2017测试标准，采用KS-653D氧指数测定仪，在室温下，通入23℃±2℃的氧、氮混合气体，将热塑性纤维放置于夹具内，与火焰接触30秒，每隔5秒移开一次，观察样品是否燃烧。从而测得样品在最低氧气浓度下的燃点温度，该氧气浓度即LOI值，也就是极限氧指数。
【密封层的平均总厚度占隔热防火材料整体厚度的比例】
采用数码显微镜分别拍摄密封层与隔热防火材料整体的横截面，拍摄倍率为50倍，并随机分别测定密封层与隔热防火材料整体各5处的断面高度，取该5次测试结果的平均值，分别作为密封层与隔热防火材料的平均厚度。其中，上、下两层密封层的平均厚度总和记为D 1，防火隔热材料整体的平均厚度记为D 2，密封层的平均总厚度占隔热防火材料整体厚度的比例的计算公式如下：密封层的平均总厚度占隔热防火材料整体厚度的比例＝D 1/D 2×100％。
【蓄热材料受热时释放出的水分重量与隔热防火材料重量的比例】
取尺寸为8cm×8cm的方形隔热防火材料，将该样品放置在在温度为600℃，面积为10cm×10cm的加热平台上进行加热处理，为了防止样品发生意外熔化而污染加热平台，在被测隔热防火材料的上、下两侧各放置一枚8cm×8cm、厚度为1mm的方形铜板。铜板可以迅速导热，因此可认为被加热面温度等同于加热平台的温度。计量加热前隔热防火材料的重量为M 0，计量加热处理后至恒重的隔热防火材料的重量为M 1，根据以下公式计算蓄热材料受热时释放出的水分重量与隔热防火材料重量的比例：
水分重量与隔热防火材料的重量比(％)＝(M 0-M 1)/M 0×100％。
【蓄热层的平均厚度与隔热层的平均厚度的比例】
采用数码显微镜分别拍摄蓄热层与隔热层的横截面，拍摄倍率为50倍，并随机分别测定蓄热层与隔热层各5处的断面高度，取该5次测试结果的平均值，分别作为蓄热层与隔热层的平均厚度。其中，上、下两层蓄热层的平均厚度总和记为H 1，隔热层的平均厚度记为H 2，蓄热层的平均总厚度占隔热层的比例的计算公式如下：蓄热层的平均总厚度占隔热防火材料整体厚度的比例＝H 1/H 2×100％。
【纤维构造体中孔径比率】
根据ASTM F316测试标准，采用美国施多威尔公司的毛细流动孔隙测量仪(设备简称PMI，设备型号CFP-1100-AEX)，测试纤维构造体的孔径。测试原理是：从润湿液中将浸润饱和的待测样品取出，放入样品室密封好，然后用气体从样品前面流向样品室。用计算机控制气体压力，使之缓缓增加、直到它达到足以克服最大孔径对应的液体的毛细血管作用，即泡点压力。当压力进一步增加，形成可测量初的气体流动，直到能流动的液体被排空为止。用干样品也会产生流速对压力的数据，并且将其进行实时存储与显示。孔隙直径的计算参考以下公式，采用设备自带的应用程序，计算5～50μm之间的孔所占的比率，从而得到得最终测试结果。
D＝4γCosθ/p，
其中，
D＝孔隙直径，
γ＝液体的表面张力，
θ＝接触角，
p＝压差。
【中空微粒的重量比】
将未附着中空微粒的多孔质材料进行称重，重量记为S 0，中空微粒附着后的重量记为S 1，计算出中空微粒的重量为S 1-S 0。
当被测的多孔质材料中已含有中空微粒时，称取该样品的重量，记为S 1，再使用与中空微粒亲和性较高的溶剂去除中空微粒。可以选择以下材料作为溶剂，比如水、甲醇、乙醇、丙酮、正己烷、甲基丙酮等，可以使用其中一种，也可以多种组合使用，能够使多孔材料不软化、不变形、不溶解的溶剂均可使用。
可以适当选择清洗温度和时间，但需要选择使多孔材料不软化、不变形、不溶解的溶剂。另外，洗净可以是浸渍处理，也可以增加机械作用，例如超声波洗净之类的方法。
洗涤后进行干燥处理，选择使多孔材料不软化、不变形、不熔化的温度和时间。第一次清洗、干燥后的多孔质材料的重量，测量标记为A 1。当第二次清洗、干燥后的多孔质材料的重量，测量标记为A 2，当(A 1-A 2)/A 1×100(％)的重量减少率在0.5％以下时，可以认为已经完全去除了中空微粒,称取此时该样品的重量，记为S 0，计算出中空微粒的重量为S 1-S 0，中空微粒的重量比的计算公式如下：
中空微粒的重量比(％)＝(S 1-S 0)/S 0×100％。
【连续片状材料的气密性】
根据JIS L 1096A法，将连续片状材料放置于通气度测试仪上，在125Pa压差下，测试其透气性。随机取N＝5进行测试，并将测试结果取平均值，作为最终的气密性测试结果。
【隔热防火材料两面温度差】
将隔热防火材料放置于已经稳定加热后的加热平台上，加热平台稳定后的设定温度为600℃，记为T 1，测试该隔热防火材料加热对面的温度变化，并取测试20分钟内的最高温度，记为T 2，隔热防火材料两面温度差的计算公示如下：
隔热防火材料的两面温度差(℃)＝T 1-T 2。
【隔热性】
隔热防火材料两面温度差越大，代表隔热性越好。隔热防火材料两面温度差温差大于400℃，判定为优异，记为S；隔热防火材料两面温度差温差为300℃～400℃，判定为良好，记为A；隔热防火材料两面温度差温差为大于等于250℃小于300℃，判定为一般，记为B；隔热防火材料两面温度差为小于250℃，判定为不好，记为F。
【压缩弹性率】
使用SE～15型压缩弹性试验机，在标准模式下，测定加压0.3MPa时样品厚度T 1，然后加压到2MPa，放置一分钟后测试厚度T 2，然后去除压力放置一分钟后，再次测定加压0.3MPa时样品厚度T 3，精确到0.01mm。根据以下公式计算压缩弹性率：压缩弹性率(％)＝(T 3-T 2)/(T 1-T 2)×100％。
在以下实施例说明之前，对实施例中所涉及的材料进行详细说明。
【构成多孔质材料的纤维】
<非熔融纤维>
采用Zoltek公司生产的预氧化纤维“Pyron”(美国注册商标)，长度为50mm、纤度为1.7分特、高温收缩率为1.6％、常温导热系数围为0.033W/(m·K)(制得克重为200g/m 2、厚度为2mm的针刺毡进行测试)。
<热塑性纤维>
采用东丽株式会社生产的聚苯硫醚纤维“TORCON”(注册商标)，单纤维直径为2.2分特(直径为14.5微米)、长度为51mm、品名为S371、LOI为34％、熔点为284℃、玻璃化转移温度为90℃，卷缩数为14(个/25mm)、卷缩率为15％。
【中空微粒】
采用深圳中凝科技有限公司生产的气凝胶粉体，型号为AG-D，该气凝胶粉体在常温下的导热系数为0.018W/(m·K)、孔隙率为90％、比表面积为800m 2/g。
【蓄热材料】
采用扬州帝蓝化工原料有限公司生产的阻燃级氢氧化铝粉末，氢氧化铝有效成分在99.6重量％以上，附着水含量小于0.8重量％。
【密封层】
采用黑色不透光聚酰亚胺薄膜，透光率小于1％、热收缩率小于0.1％、吸湿率小于2％。
实施例1
采用60重量％的LOI值为34％的聚苯硫醚纤维与40重量％的预氧化纤维进行混棉、梳理、铺网，然后在针刺密度为400针/cm 2下进行针刺加工，制得厚度为1.0mm、克重为300g/cm 3、体积密度为0.30g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.037W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的85％；将上述制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为50微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为17％；将氢氧化铝粉末与聚乙烯热熔胶颗粒混合后，将混合颗粒以撒进的方式均匀铺放在上述制备好的隔热层上、下两侧，以膜的形式形成一层氢氧化铝粉末层，即为蓄热层；再采用气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜从六面进行封装，并通过加热加压使密封材固定于隔热层的外表面，最终制得隔热防火材料，评价其各物性，并示于表1中。
实施例2
采用60重量％的LOI值为34％的聚苯硫醚纤维与40重量％的预氧化纤维进行混棉、梳理、铺网，然后在针刺密度为300针/cm 2下进行针刺加工，制得厚度为1.5mm、克重为300g/cm 3、体积密度为0.20g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.035W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的60％；将上述制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为50微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为24％。其余同实施例1，最终制得本发明的隔热防火材料，评价其各物性，并示于表1中。
实施例3
采用60重量％的LOI值为34％的聚苯硫醚纤维与40重量％的预氧化纤维进行混棉、梳理、铺网，然后在针刺密度为150针/cm 2下进行针刺加工，制得厚度为4.2mm、克重为300g/cm 3、体积密度为0.07g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.033W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的35％；将上述制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为50微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为43％。其余同实施例1，最终制得本发明的隔热防火材料，评价其各物性，并示于表1中。
实施例4
将氢氧化铝粉末与聚乙烯热熔胶颗粒混合后，将混合颗粒以撒进的方式均匀铺放在制备好的隔热层上、下两侧，以膜的形式形成一层氢氧化铝粉末层，即为蓄热层；再采用气密性为0.1cm 3/cm 2/s、厚度为80微米的聚酰亚胺薄膜从六面进行封装，并通过加热加压使密封材固定于隔热层的外表面，其余同实施例1，最终制得隔热防火材料，评价其各物性，并示于表1中。
实施例5
将氢氧化铝粉末与液态聚酰亚胺难燃树脂均匀混合，形成含有氢氧化铝的难燃树脂液，然后将其均匀涂敷于针刺无纺布上、下两面，在170℃温度下干燥固化后室温冷却，在针刺无纺布上、下两面形成一层附着有氢氧化铝粉末的聚酰亚胺难燃树脂固化膜作为 蓄热层，最后制得分布在隔热层两侧的蓄热层为一体的隔热防火材料，此时，蓄热层即为密封层。其余同实施例2。评价其各物性，并示于表1中。
实施例6
通过物理填充的方式将氢氧化铝粉末撒进针刺无纺布与气凝胶的复合材料中，制得隔热层，此时，隔热层即为蓄热层，复合材料的制备方法同实施例2。再采用气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜从六面进行封装，并通过加热加压使密封材固定于隔热层的外表面，最终制得本发明的隔热防火材料，评价其各物性，并示于表1中。
实施例7
将氢氧化铝粉末与液态聚酰亚胺难燃树脂均匀混合，形成含有氢氧化铝的难燃树脂液，然后将其均匀涂敷于针刺无纺布上、下两面，在170℃温度下干燥固化后室温冷却，在针刺无纺布上、下两面形成一层附着有氢氧化铝粉末的聚酰亚胺酸难燃树脂固化膜作为蓄热层，最后制得分布在隔热层两侧的蓄热层为一体的隔热防火材料，此时，蓄热层即为密封层。其余同实施例2。评价其各物性，并示于表1中。
实施例8
将氢氧化铝粉末与液态聚酰亚胺难燃树脂均匀混合，形成含有氢氧化铝的难燃树脂液，然后将其均匀涂敷于针刺无纺布上、下两面，在170℃温度下干燥固化后室温冷却，在针刺无纺布上、下两面形成一层附着有氢氧化铝粉末的聚酰亚胺酸难燃树脂固化膜作为蓄热层，最后制得分布在隔热层两侧的蓄热层为一体的隔热防火材料，此时，蓄热层即为密封层。其余同实施例1。评价其各物性，并示于表1中。
实施例9
采用60重量％的LOI值为34％的聚苯硫醚纤维与40重量％的预氧化纤维进行混棉、梳理、铺网，然后在针刺密度为400针/cm 2下进行针刺加工，制得厚度为1.0mm、克重为300g/cm 3、体积密度为0.30g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.037W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的85％；将上述制得的针刺无纺布浸入均匀分散的中空玻璃微珠分散液中，然后再将充分吸收中空玻璃微珠分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为1000微米的中空玻璃微珠粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得中空玻璃微珠粉末的重量比为17％；将氢氧化镁粉末与聚乙烯热熔胶颗粒混合后，将混合颗粒以撒进的方式均匀铺放在上述制备好的隔热层上、下两侧，以膜的形式形成一层氢氧化镁粉末层，即为蓄热层；再采用气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜从上、下表面以及前、后侧面进行四面封装，并通过加热加压使密封材固定于隔热层的外表面，最终制得隔热防火材料，评价其各物性，并示于表1中。
实施例10
将十水硫酸钠粉末与聚乙烯热熔胶颗粒混合后，将混合颗粒以撒进的方式均匀铺放在上述制备好的隔热层上、下两侧，以膜的形式形成一层十水硫酸钠粉末层，即为蓄热层；再采用气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜从上、下表面以及前、后侧面进行四面封装，并通过加热加压使密封材固定于隔热层的外表面，其余同实施例9，最终制得隔热防火材料，评价其各物性，并示于表1中。
实施例11
将十二水硫酸铝钾粉末与聚乙烯热熔胶颗粒混合后，将混合颗粒以撒进的方式均匀铺放在上述制备好的隔热层上、下两侧，以膜的形式形成一层十二水硫酸铝钾粉末层，即为蓄热层；再采用气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜从上、下 表面以及前、后侧面进行四面封装，并通过加热加压使密封材固定于隔热层的外表面，其余同实施例9，最终制得隔热防火材料，评价其各物性，并示于表2中。
实施例12
将实施例1中制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为500微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为17％。其余同实施例1，最终制得本发明的隔热防火材料，评价其各物性，并示于表2中。
实施例13
将实施例1中制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为1000微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为17％。其余同实施例1，最终制得本发明的隔热防火材料，评价其各物性，并示于表2中。
实施例14
将实施例1中制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为50微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为12％。其余同实施例1，最终制得本发明的隔热防火材料，评价其各物性，并示于表2中。
实施例15
采用60重量％的LOI值为28％的难燃粘胶纤维与40重量％的玻璃纤维进行混棉、梳理、铺网，然后在针刺密度为150针/cm 2下进行针刺加工，制得厚度为1.0mm、克重为300g/cm 3、体积密度为0.30g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.037W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的45％。其余同实施例1。评价本发明的隔热防火材料的各物性，并示于表2中。
实施例16
采用60重量％的LOI值为34％的难燃粘胶纤维与40重量％的玻璃纤维进行混棉、梳理、铺网，然后在针刺密度为400针/cm 2下进行针刺加工，制得厚度为1.0mm、克重为300g/cm 3、体积密度为0.30g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.032W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的85％。其余同实施例1。评价本发明的隔热防火材料的各物性，并示于表2中。
实施例17
采用聚苯硫醚长丝与玻璃纤维进行编织，制得厚度为1.9mm、克重为420g/cm 3、体积密度为0.22g/cm 3的经编间隔织物作为纤维构造体，测得该纤维构造体的导热系数为0.042W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的58％；将上述制得的经编间隔织物浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为50微米的气凝胶粉末附着于经编间隔织物内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为25％。再采用气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜从六面进行封装，并通过加热加压使密封材固定于隔热层的外表面，最终制得隔热防火材料，评价其各物性，并示于表2中。
实施例18
隔热层的制备方法同实施例1，所得的隔热层即为本发明的隔热防火材料，评价其各物性，并示于表2中。
将实施例1～18中制得的隔热防火材料应用于动力电池中。
比较例1
采用60重量％的LOI值为34％的聚苯硫醚纤维与40重量％的预氧化纤维进行混棉、梳理、铺网，然后在针刺密度为600针/cm 2下进行针刺加工，制得厚度为0.6mm、克重为300g/cm 3、体积密度为0.50g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.051W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的96％；将上述制得的针刺无纺布浸入均匀分散的气凝胶分散液中，然后再将充分吸收气凝胶分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为50微米的气凝胶粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得气凝胶粉末的重量比为5％。其余同实施例1。评价该材料的各物性，并示于表3中。
比较例2
将实施例9中制得的针刺无纺布浸入均匀分散的中空玻璃微珠分散液中，然后再将充分吸收中空玻璃微珠分散液后的纤维构造体进行轻微加压处理，将表面多余的分散液去除，再进行低温干燥，得到平均直径为1500微米的中空玻璃微珠粉末附着于针刺无纺布内部及表面的复合材料作为隔热层，测得中空玻璃微珠粉末的重量比为17％。其余同实施例9。评价该材料的各物性，并示于表3中。
比较例3
将平均直径为50微米的气凝胶粉末堆积成1.4mm厚的长方体，并固定于气密性为0.5cm 3/cm 2/s、厚度为50微米的聚酰亚胺薄膜形成的袋体内。其余同实施例1，最终制得隔热防火材料，评价其各物性，并示于表3中。
比较例4
采用60重量％的LOI值为34％的聚苯硫醚纤维与40重量％的预氧化纤维进行混棉、梳理、铺网，然后在针刺密度为400针/cm 2下进行针刺加工，制得厚度为1.0mm、克重为300g/cm 3、体积密度为0.30g/cm 3的针刺无纺布作为纤维构造体，测得该纤维构造体的导热系数为0.037W/(m·K)，纤维构造体中孔径在5～50μm之间的孔占全部孔的85％，将上述制得的针刺无纺布作为隔热层；蓄热层与密封层的制备方法同实施例1，最终制得隔热防火材料，评价其各物性，并示于表3中。
表1
Figure PCTCN2020100076-appb-000001
表2
Figure PCTCN2020100076-appb-000002
表3
Figure PCTCN2020100076-appb-000003
根据上述表：
(1)由实施例1-3可知，同等条件下，多孔质材料的体积密度越小，隔热层中含中空微粒的重量比越多，所得隔热防火材料的隔热性越好。
(2)由实施例5与实施例7可知，同等条件下，后者的密封层的平均总厚度占隔热防火材料整体厚度的比例在进一步优选范围内，与前者相比，所得隔热防火材料的隔热性好。
(3)由实施例1与实施例4可知，同等条件下，前者的蓄热层的平均厚度与隔热层的平均厚度的比例在更优选范围内，与后者相比，所得隔热防火材料的隔热性好。
(4)由实施例9-11可知，同等条件下，实施例9中蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例不在优选范围内，所得隔热防火材料的隔热性略低。
(5)由实施例1、12、13可知，同等条件下，气凝胶的平均直径越大，所得隔热防火材料中的空隙就越多，隔热性略低。
(6)由实施例1与实施例14可知，同等条件下，前者的气凝胶重量比在优选范围内，与后者相比，所得隔热防火材料的隔热性好。
(7)由实施例15与实施例16可知，同等条件下，后者的纤维构造体的孔径占比在优选范围内，与前者相比，所得隔热防火材料的隔热性好。
(8)由比较例1与实施例1可知，同等条件下，前者的多孔质材料的体积密度过大，隔热层中含气凝胶的重量比急剧减少，隔热性变差。
(9)由比较例2与实施例9可知，同等条件下，前者的中空玻璃微珠的平均直径过大，所得材料中的空隙更多，隔热性变差。
(10)比较例3中无多孔质材料，气凝胶粉末无法得到基材的稳定支撑，出现掉粉或隔热不均等现象，隔热性变差。
(11)比较例4中无中空微粒，无法阻隔热量传递，隔热性变差。

Claims (16)

  1. 一种隔热防火材料，其特征在于：所述隔热防火材料中至少含有隔热层，所述隔热层中含有多孔质材料和中空微粒，所述多孔质材料的体积密度为0.05～0.30g/cm 3，所述中空微粒的平均直径为30～1000μm，所述隔热防火材料经过碳化处理后的常温导热系数为0.040W/(m·K)以下。
  2. 根据权利要求1所述的隔热防火材料，其特征在于：所述隔热防火材料中含有密封层，所述密封层为连续片状材料，所述密封层位于隔热层的至少相对两面，所述密封层的平均总厚度占隔热防火材料整体厚度的比例为0.5～90.0％。
  3. 根据权利要求1或2所述的隔热防火材料，其特征在于：所述隔热防火材料中含有蓄热材料，所述蓄热材料为水合物或金属的氢氧化物，所述蓄热材料受热时释放出的水分重量相对于隔热防火材料的重量比例为2.0～25.0％。
  4. 根据权利要求3所述的隔热防火材料，其特征在于：所述蓄热材料为层状结构分布于隔热层相对两侧，所述蓄热层的平均厚度与隔热层的平均厚度的比例为10～90％。
  5. 根据权利要求3或4所述的隔热防火材料，其特征在于：所述蓄热材料分散于隔热层中。
  6. 根据权利要求3或4或5所述的隔热防火材料，其特征在于：所述蓄热材料分散于密封层中。
  7. 根据权利要求1～6任一项所述的隔热防火材料，其特征在于：所述多孔质材料为纤维构造体。
  8. 根据权利要求7所述的隔热防火材料，其特征在于：所述纤维构造体中孔径在5～50μm之间的孔占全部孔的50％以上。
  9. 根据权利要求7或8所述的隔热防火材料，其特征在于：在常温下，所述纤维构造体的导热系数低于0.040W/(m·K)。
  10. 根据权利要求9所述的隔热防火材料，其特征在于：所述纤维构造体为含有LOI值在28％以上的热塑性纤维与非熔融纤维形成的无纺布。
  11. 根据权利要求1～6任一项所述的隔热防火材料，其特征在于：所述中空微粒为气凝胶粉末。
  12. 根据权利要求11所述的隔热防火材料，其特征在于：所述隔热防火材料中气凝胶粉末的重量比为15％以上。
  13. 根据权利要求2～6任一项所述的隔热防火材料，其特征在于：所述连续片状材料的气密性在20cm 3/cm 2/s以下。
  14. 根据权利要求13所述的隔热防火材料，其特征在于：所述连续片状材料为膜状材料、由纤维纺织品形成的片材或由连续树脂形成的片状材料。
  15. 根据权利要求1～14任一项所述的隔热防火材料，其特征在于：所述隔热防火材料的两面温度差大于300℃。
  16. 一种权利要求1～15任一项所述的隔热防火材料在电池中的应用。
PCT/CN2020/100076 2019-07-03 2020-07-03 一种隔热防火材料及其用途 Ceased WO2021000927A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202080044134.7A CN113939942B (zh) 2019-07-03 2020-07-03 一种隔热防火材料及其用途

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN201910594449.8 2019-07-03
CN201910594449 2019-07-03
CN201910909245 2019-09-25
CN201910909245.9 2019-09-25

Publications (1)

Publication Number Publication Date
WO2021000927A1 true WO2021000927A1 (zh) 2021-01-07

Family

ID=74101202

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/100076 Ceased WO2021000927A1 (zh) 2019-07-03 2020-07-03 一种隔热防火材料及其用途

Country Status (2)

Country Link
CN (1) CN113939942B (zh)
WO (1) WO2021000927A1 (zh)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113025226A (zh) * 2021-03-22 2021-06-25 朗缪环保科技(天津)有限公司 气凝胶防火保温隔热涂料
CN113637233A (zh) * 2021-07-23 2021-11-12 浙江理工大学 一种全生物质节能防火用气凝胶的制备方法
CN113785431A (zh) * 2021-02-05 2021-12-10 气凝胶研发私人有限公司 用于电池的隔热装置
CN113858723A (zh) * 2021-09-29 2021-12-31 湖北三江航天红阳机电有限公司 一种梯度热防护层结构试板及其制备方法
CN114395336A (zh) * 2021-12-02 2022-04-26 广东航邦新材料科技有限公司 一种新型隔热防护材料及其生产工艺
CN114628844A (zh) * 2022-03-24 2022-06-14 广州小鹏汽车科技有限公司 电池箱、动力电池总成及车辆
CN114643762A (zh) * 2022-03-09 2022-06-21 苏州中纺学面料产业研究院 一种阻燃隔热面料的制备方法
WO2022199642A1 (zh) * 2021-03-25 2022-09-29 东丽纤维研究所（中国）有限公司 一种耐火焰毡
CN115180836A (zh) * 2022-07-11 2022-10-14 南通金鹏玻纤制品有限公司 一种阻燃玻纤布及其生产工艺
CN115476524A (zh) * 2021-06-15 2022-12-16 东莞市硅翔绝缘材料有限公司 一种新能源汽车电池缓冲隔热垫的制备工艺
CN115799729A (zh) * 2023-02-01 2023-03-14 中创新航科技股份有限公司 电池组以及电池装置
CN116166073A (zh) * 2023-04-26 2023-05-26 深圳市博硕科技股份有限公司 具有学习功能的动力电池隔热棉裁切温控系统
CN116278252A (zh) * 2023-03-17 2023-06-23 吴江德伊时装面料有限公司 一种多组分保温高密涤纶面料及其制备方法
WO2024191623A3 (en) * 2023-03-03 2024-12-12 Aspen Aerogels, Inc. Thermal barriers with reinforcement structures
CN119912726A (zh) * 2025-04-01 2025-05-02 泰和新材集团股份有限公司 一种芳纶气凝胶绝热板及其制备方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12162766B1 (en) 2023-06-29 2024-12-10 Lg Chem, Ltd. Aerogel composite
US12162767B1 (en) 2023-07-26 2024-12-10 Lg Chem, Ltd. Aerogel composite
CN119381614A (zh) * 2023-07-25 2025-01-28 蔚来电池科技(安徽)有限公司 电池包和用电装置
US12326214B2 (en) 2023-08-30 2025-06-10 Lg Chem, Ltd. Aerogel composite
US12162260B1 (en) 2023-10-05 2024-12-10 Lg Chem, Ltd. Aerogel composite
US12428352B1 (en) 2024-03-27 2025-09-30 Lg Chem, Ltd. Aerogel composite

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3346180A1 (de) * 1983-12-21 1985-08-29 Grünzweig + Hartmann und Glasfaser AG, 6700 Ludwigshafen Starrer waermedaemmkoerper
CN1205751A (zh) * 1995-12-21 1999-01-20 德国赫彻斯特研究技术两合公司 含有至少一种热塑性纤维材料的纤维组织－气凝胶-复合材料,其制备方法及其应用
CN1622852A (zh) * 2002-01-29 2005-06-01 卡伯特公司 耐热气凝胶绝缘复合材料及其制备方法,气凝胶粘合剂组合物及其制备方法
WO2007011750A3 (en) * 2005-07-15 2009-04-16 Aspen Aerogels Inc Secured aerogel composites and method of manufacture thereof
CN103249560A (zh) * 2010-10-08 2013-08-14 日东电工株式会社 热功能性阻燃聚合物构件
CN108883597A (zh) * 2016-01-27 2018-11-23 W.L.戈尔及同仁股份有限公司 包含增强的气凝胶复合物的层叠体

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5081464B2 (ja) * 2007-02-14 2012-11-28 ニチアス株式会社 断熱材及びその製造方法
CN204144345U (zh) * 2014-08-01 2015-02-04 北京新能源汽车股份有限公司 一种用于电动汽车的动力电池箱体
JP2017166610A (ja) * 2016-03-17 2017-09-21 イビデン株式会社 断熱保温部材
CN107914428A (zh) * 2017-12-19 2018-04-17 深圳市德镒盟电子有限公司 一种新能源汽车动力电池用隔热防火材料
CN207697181U (zh) * 2017-12-19 2018-08-07 深圳市德镒盟电子有限公司 一种新能源汽车动力电池用隔热防火材料

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3346180A1 (de) * 1983-12-21 1985-08-29 Grünzweig + Hartmann und Glasfaser AG, 6700 Ludwigshafen Starrer waermedaemmkoerper
CN1205751A (zh) * 1995-12-21 1999-01-20 德国赫彻斯特研究技术两合公司 含有至少一种热塑性纤维材料的纤维组织－气凝胶-复合材料,其制备方法及其应用
CN1622852A (zh) * 2002-01-29 2005-06-01 卡伯特公司 耐热气凝胶绝缘复合材料及其制备方法,气凝胶粘合剂组合物及其制备方法
WO2007011750A3 (en) * 2005-07-15 2009-04-16 Aspen Aerogels Inc Secured aerogel composites and method of manufacture thereof
CN103249560A (zh) * 2010-10-08 2013-08-14 日东电工株式会社 热功能性阻燃聚合物构件
CN108883597A (zh) * 2016-01-27 2018-11-23 W.L.戈尔及同仁股份有限公司 包含增强的气凝胶复合物的层叠体

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113785431A (zh) * 2021-02-05 2021-12-10 气凝胶研发私人有限公司 用于电池的隔热装置
CN113785431B (zh) * 2021-02-05 2024-02-06 气凝胶研发私人有限公司 用于电池的隔热装置
EP4064423A4 (en) * 2021-02-05 2022-11-30 Aerogel R&D Pte. Ltd. Thermal insulation element for batteries
CN113025226A (zh) * 2021-03-22 2021-06-25 朗缪环保科技(天津)有限公司 气凝胶防火保温隔热涂料
CN116711132A (zh) * 2021-03-25 2023-09-05 东丽纤维研究所（中国）有限公司 一种耐火焰毡
WO2022199642A1 (zh) * 2021-03-25 2022-09-29 东丽纤维研究所（中国）有限公司 一种耐火焰毡
CN115476524A (zh) * 2021-06-15 2022-12-16 东莞市硅翔绝缘材料有限公司 一种新能源汽车电池缓冲隔热垫的制备工艺
CN113637233B (zh) * 2021-07-23 2022-11-29 浙江理工大学 一种全生物质节能防火用气凝胶的制备方法
CN113637233A (zh) * 2021-07-23 2021-11-12 浙江理工大学 一种全生物质节能防火用气凝胶的制备方法
CN113858723A (zh) * 2021-09-29 2021-12-31 湖北三江航天红阳机电有限公司 一种梯度热防护层结构试板及其制备方法
CN113858723B (zh) * 2021-09-29 2023-09-19 湖北三江航天红阳机电有限公司 一种梯度热防护层结构试板及其制备方法
CN114395336A (zh) * 2021-12-02 2022-04-26 广东航邦新材料科技有限公司 一种新型隔热防护材料及其生产工艺
CN114643762B (zh) * 2022-03-09 2024-03-08 苏州中纺学面料产业研究院 一种阻燃隔热面料的制备方法
CN114643762A (zh) * 2022-03-09 2022-06-21 苏州中纺学面料产业研究院 一种阻燃隔热面料的制备方法
CN114628844A (zh) * 2022-03-24 2022-06-14 广州小鹏汽车科技有限公司 电池箱、动力电池总成及车辆
CN115180836A (zh) * 2022-07-11 2022-10-14 南通金鹏玻纤制品有限公司 一种阻燃玻纤布及其生产工艺
CN115799729A (zh) * 2023-02-01 2023-03-14 中创新航科技股份有限公司 电池组以及电池装置
WO2024191623A3 (en) * 2023-03-03 2024-12-12 Aspen Aerogels, Inc. Thermal barriers with reinforcement structures
CN116278252A (zh) * 2023-03-17 2023-06-23 吴江德伊时装面料有限公司 一种多组分保温高密涤纶面料及其制备方法
CN116166073B (zh) * 2023-04-26 2023-07-21 深圳市博硕科技股份有限公司 具有学习功能的动力电池隔热棉裁切温控系统
CN116166073A (zh) * 2023-04-26 2023-05-26 深圳市博硕科技股份有限公司 具有学习功能的动力电池隔热棉裁切温控系统
CN119912726A (zh) * 2025-04-01 2025-05-02 泰和新材集团股份有限公司 一种芳纶气凝胶绝热板及其制备方法

Also Published As

Publication number Publication date
CN113939942B (zh) 2024-12-17
CN113939942A (zh) 2022-01-14

Similar Documents

Publication Publication Date Title
WO2021000927A1 (zh) 一种隔热防火材料及其用途
CN207587926U (zh) 电池模块的吸热隔热结构
US8592076B2 (en) Battery pack
KR20220143100A (ko) 배터리용 열 관리 다층 시트
KR20220150347A (ko) 배터리용 열 관리 다층 시트
JP7578847B2 (ja) 電池ベースのエネルギー貯蔵システムにおける熱伝播を軽減するシステム及び方法
TW202319232A (zh) 用於緩解電能儲存熱事件之材料、系統及方法
JP7144629B2 (ja) 断熱層を有するシングルセル用ケース
CN212076863U (zh) 具有二氧化硅气凝胶玻纤毡复合材料薄板的隔热垫制品
US20230087017A1 (en) Thermal barrier component for mitigating thermal runaway in batteries
CN219066972U (zh) 热传递抑制片以及电池组
CN220341331U (zh) 热传递抑制片及电池组
US20240250334A1 (en) Thermal runaway suppression sheet and battery pack and/or battery module using the same
CN220341328U (zh) 热传递抑制片及电池组
CN113506935A (zh) 电池模组用热蔓延防护板、电池模组和电池包
JP2022125585A (ja) 断熱材
US20240124670A1 (en) Fire-resistant, fire retardant and/or thermal insulation
CN117861103A (zh) 具有复合系统的防火装置、复合系统和具有防火装置的电池包
CN116799353A (zh) 防火构造体及其制造方法、以及电池模块
CN217704995U (zh) 热防护层及电动汽车电池用热防护结构
CN112038511A (zh) 电动汽车锂离子动力蓄电池缓冲减振用表面封装的二氧化硅气凝胶毡制品及其制造方法
JP7670939B1 (ja) 電気自動車用バッテリーセル間断熱材シート
EP4570757A1 (en) Heat control member comprising wet-gel blanket
Li et al. Development of phase change material for thermal management of lithium-ion batteries: a review
KR20240126782A (ko) 열반응형 방화재 조성물 및 이를 이용한 열반응형 방화재

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20835454

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20835454

Country of ref document: EP

Kind code of ref document: A1