WO2021000927A1

WO2021000927A1 - Thermal-insulating and fireproof material and application thereof

Info

Publication number: WO2021000927A1
Application number: PCT/CN2020/100076
Authority: WO
Inventors: 张尤娟; 武庭轩; 石彦芳; 二宫有希; 原田大
Original assignee: 东丽纤维研究所（中国）有限公司
Priority date: 2019-07-03
Filing date: 2020-07-03
Publication date: 2021-01-07
Also published as: CN113939942A

Abstract

Disclosed in the present invention are a thermal-insulating and fireproof material and an application thereof. The thermal-insulating and fireproof material at least contains a thermal-insulating layer, wherein a porous material and hollow particles are contained in the thermal-insulating layer, the volume density of the porous material is 0.05-0.30 g/cm³, the average diameter of the hollow particles is 30-1000 μm, and the thermal conductivity coefficient of the thermal-insulating and fireproof material after carbonization treatment at normal temperature is 0.040 W/(m•K) or below. The thermal-insulating and fireproof material of the present invention has the characteristics of good flame retardance, high temperature resistance, a small thermal conductivity coefficient, and being lightweight, and can be applied between battery cells of a power battery.

Description

Heat insulation and fireproof material and its use

Technical field

The invention relates to a heat insulation and fireproof material and its use.

Background technique

In the power batteries of traditional electric vehicles, heat-insulating and fire-resistant materials are generally formed of high-temperature-resistant flame-retardant inorganic materials, such as mica materials. However, due to the high specific gravity of mica, in actual use, when used as a heat insulating sheet between two batteries, the overall weight of the battery increases, which is not conducive to the lightweight of electric vehicles, thereby affecting the range of electric vehicles.

Although increasing the number of batteries within a certain range can increase the range of electric vehicles, the number of batteries is restricted due to the limited volume of the car and the increase in weight. In order to achieve the purpose of increasing the cruising range, increase the battery capacity under the condition of the same volume and weight, that is, increase the energy density of the battery. However, it is more difficult to increase the energy density of electric vehicle batteries.

In addition, mica flakes are hard and brittle, and are extremely difficult to compress in the thickness direction. When the battery is in use or charging, when the battery core expands in the thickness direction, the mica sheet is squeezed but difficult to be compressed. Although 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.

For example, 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. In addition, 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. , It is difficult to buckle, and 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. In addition, although silica-based inorganic fibers containing hydroxyl groups are used in the insulator, 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.

For example, 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.

For example, 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. In addition, 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.

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. In this invention, 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. Moreover, 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.

Summary of the invention

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 technical solution of the present invention is as follows: 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, and 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 μm, and 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.

In the above-mentioned fiber structure, pores having a pore diameter between 5 and 50 μm preferably account for 50% or more of all pores.

At normal temperature, 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 beneficial effects of the present invention: 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.

Description of the drawings

Figure 1 is a schematic diagram of the thermal insulation and fireproof material of the present invention. In the figure, A is the thermal insulation layer, B is the thermal storage layer, C is the sealing layer, and 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.

Figure 2 is a schematic diagram of the heat insulation and fireproof material of the present invention. In the figure, A is the heat insulation layer, B is the heat storage layer, and 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.

Figure 3 is a schematic diagram of the thermal insulation and fireproof material of the present invention. In the figure, A is the thermal insulation layer, B is the heat storage layer, and 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.

Detailed ways

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 μm, 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. For example, 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. For example, 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 On the porous material of the mesh structure, 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 30μm, 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 1000μm, 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. Since the particle size of the hollow particles is too large, the dispersion of the hollow particles in the porous material becomes extremely uneven, resulting in the deterioration of the uniformity of the heat insulation performance of the entire material. In consideration of the dispersion stability of the hollow particles and the uniformity of heat insulation performance, the average diameter of the hollow particles is preferably 50 to 800 μm, more preferably 50 to 500 μm. 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. As a thermal insulation material between cells, it can effectively delay or block the thermal runaway of cells, thereby delaying the time of heat transfer to the entire battery system. Therefore, 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. If the 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. Taking into account the bulk density of the porous material in the heat-insulating fire-retardant material and the content of hollow particles, 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. Loss of control, in severe cases, will cause the drivers and passengers to escape too late and cause serious casualties. Therefore, it is preferable to provide a sealing layer on at least two opposite sides of the heat insulating layer. 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. 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. ; 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.

When the sealing layer is a film-like material, the average thickness of the sealing layer is preferably 5 to 200 μm. 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.

When the sealing layer is a fiber textile, the average thickness of the sealing layer is preferably 100-400 μm. 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. In particular, high-density flame-retardant fiber textiles with a thickness of 100-200μm 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.

When the sealing layer is a resin-formed sheet material, since 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. For thermal insulation and fireproof materials, the more heat absorption is. In consideration of the overall thickness of the heat insulating and fireproof material, the average thickness of the sealing layer is preferably 200 to 1000 μm. If 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. In sum, 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. 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. 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. When 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. On the other hand, if 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. When 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. Taking into account the performance requirements of thermal insulation and fire protection, cushioning and shock absorption, and lightweight, as well as the sealing performance and compression resilience when applied between the cells, 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. During the dehydration process, 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. Due to the large difference in the decomposition temperature of metal hydroxides, for example, 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, and 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. Considering the actual application environment of the thermal insulation and fireproof material of the present invention, metal hydroxides with a decomposition temperature of 100 to 1200°C are preferred, such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide and the like. In addition, from the viewpoint of heat storage density, it is not only preferable that 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. Considering the overall quality and thermal insulation performance of the sample after composite processing, 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. However, when such 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. ; If the weight of the water released by the heat storage material is too high relative to the weight of the heat insulation and fireproof material, 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. When the prepared thermal insulation fireproof material is installed between the batteries, 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. In consideration of the thermal insulation properties and weight reduction of the entire heat insulating and fireproof material, 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. 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. Thermal runaway; if 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. And when 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. When 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. When 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. In consideration of the heat insulation and fire protection, cushioning and shock absorption of the heat insulation and fire protection material, as well as the sealing performance and compression resilience when applied between the cells, 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 μm. When the heat storage layer has a layered structure distributed on opposite sides of the heat-insulating layer, the thickness of each side heat storage layer is preferably 50-1000 μm. 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. Considering the overall thickness of the heat-insulating fireproof material, when the heat storage material is mixed with the heat-meltable solid flame-retardant binder particles to obtain the mixed particles, they are spread evenly on the pre-prepared heat-insulating layer In the case of upper and lower sides, the thickness of the heat storage layer on one side at this time is more preferably 50 to 200 μm. When the heat storage material is dispersed in the flame-retardant resin and is also located on both sides of the heat insulation layer as a sealing layer, the thickness of the heat storage layer on one side is preferably 200-1000 μm. If 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 μm. 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.

In the present invention, it is preferable that the heat storage material is dispersed in the heat insulation layer. When 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. Between the voids of the hollow particles, 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.

In the present invention, the heat storage material is preferably dispersed in the sealing layer. When 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. When contacting high-temperature objects, 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. Among them, 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. As the needle punched non-woven fabric, 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. Not only the processing performance is reduced, the pores contained in the entire material are reduced, and the adhesion amount of the hollow particles is reduced, and the strength of the fibers constituting the non-woven fabric is reduced, and the shearing performance is reduced. Specifically, according to the ASTM C 273/C 273M test standard, 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. At this time, 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. In addition, as a heat-insulating and fire-proof material used between the batteries, 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.

In the fiber structure of the present invention, pores having a pore diameter between 5 and 50 μm 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. If the ratio of the pores between 5-50μm in the fiber structure to the total pores is too low, 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. Considering the ease of the aerogel dispersion into the microstructure and the uniformity of powder dispersion, the pores with a pore diameter of 5-50 μm in the above-mentioned fiber structure more preferably account for 50-95% of all pores.

At room temperature, 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). As a thermal insulation material between cells, as a thermal protection material that can effectively delay or block thermal runaway of cells, and delay propagation to the entire battery system, 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. Among them, 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. When the resulting heat insulation and fireproof material encounters high temperature, it cannot be fully and effectively Block large-scale thermal runaway, which spreads from the runaway single cell to the surrounding cells; if 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%.

Because the hollow particles dispersed in the porous material are small in volume and light in specific gravity, they are easy to spill under the action of external force. In order to prevent the drop in the thermal insulation performance of the material due to the scattering and falling of hollow particles, 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. When 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. In order for the overall heat-insulating and fire-retardant material to have excellent flame retardancy, 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.

When the continuous sheet material is a sheet formed of fiber textiles, 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.

When 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. For example, ceramic coatings and silicate coatings in inorganic high temperature coatings, and fluororesin coatings and silicone high temperature coatings in organic high temperature coatings.

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℃ . When 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. Within a few minutes of heat transfer, when the temperature difference between the two sides of the material is greater than 300°C, the heat transfer speed can be effectively slowed down, thereby gaining valuable escape time for drivers and passengers. If the temperature difference between the two sides of the thermal insulation and fireproof material is too low, when the cell heats up, the heat will quickly be transferred to the adjacent cell, causing the chain heat to run out of control in a very short time, thereby endangering the lives of drivers and passengers.

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. If 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.

The present invention is further illustrated by the following examples, but the protection scope of the present invention is not limited to the examples, and the physical parameters in the examples are determined by the following methods.

【Bulk density】

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 . For a porous material with a certain thickness, 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:

Bulk density (g/cm ³ )=weight per unit area (g/m ² )/thickness (mm)/1000.

When 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. In addition, the cleaning can be immersion treatment, or mechanical action can be added, such as ultrasonic cleaning.

After washing, 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 . 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.

[Average diameter of hollow particles]

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. 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.

【Carbonization Treatment】

In an aerobic environment at room temperature, heat insulation and fireproof materials on a flat plate at a temperature of 600℃. After 15 minutes on one side, heat on the other side for 15 minutes, then stop heating and remove the processed sample. , The carbonization treatment is completed.

【Thermal Conductivity】

According to the GB/T 10295～2008 test standard, the thermal conductivity of thermal insulation and fireproof materials is measured at 25°C.

[LOI value]

According to the ISO4589-2-2017 test standard, the KS-653D oxygen index tester is used, at room temperature, a mixture of oxygen and nitrogen gas at 23℃±2℃ 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.

[The ratio of the average total thickness of the sealing layer to the overall thickness of the thermal insulation and fireproof material]

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. Among them, 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 , and the calculation formula for the ratio of the average total thickness of the sealing layer to the total thickness of the heat insulation and fire protection material is as follows : The ratio of the average total thickness of the sealing layer to the overall thickness of the heat-insulating and fire-resistant material=D ₁ /D ₂ ×100%.

[The ratio of the weight of the water released when the heat storage material is heated to the weight of the heat insulation and fireproof material]

Take a square heat insulation and fireproof material with a size of 8cm×8cm, and place the sample on a heating platform with a temperature of 600℃ and an area of 10cm×10cm for heating treatment. In order to prevent accidental melting of the sample and contaminate the heating platform, Place an 8cm×8cm square copper plate with a thickness of 1mm on the upper and lower sides of the insulation and fireproof material. The copper plate can conduct heat quickly, so it can be considered that the temperature of the heated surface is equal to the temperature of the heating platform. Measure the weight of the heat-insulating and fire-proof material before heating as M ₀ , and measure the weight of the heat-insulating and fire-proof material to a constant weight after heating treatment as M ₁ , and calculate the weight of water released when the heat storage material is heated and the heat-insulating and fire-proof material according to the following formula Weight ratio:

The weight ratio of moisture to the weight of the heat insulation and fireproof material (%)=(M ₀ -M ₁ )/M ₀ ×100%.

[The ratio of the average thickness of the heat storage layer to the average thickness of the heat insulation layer]

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. As the average thickness of the heat storage layer and the heat insulation layer. Among them, the sum of the average thickness of the upper and lower two layers of heat storage layer is recorded as H ₁ , the average thickness of the heat storage layer is recorded as H ₂ , and the calculation formula of the average total thickness of the heat storage layer to the ratio of the heat insulation layer is as follows: The ratio of the average total thickness of the layers to the overall thickness of the heat-insulating and fire-resistant material=H ₁ /H ₂ ×100%.

[Aperture ratio in fiber structure]

According to the ASTM F316 test standard, 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. Use a computer to control the gas pressure and increase it slowly until it reaches the capillary action that is sufficient to overcome the liquid corresponding to the largest pore size, that is, the bubble point pressure. When the pressure further increases, a measurable flow of gas is formed until the flowable liquid is emptied. 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 μm to obtain the final test result.

D=4γCosθ/p,

among them,

D=pore diameter,

γ = surface tension of the liquid,

θ = contact angle,

p = pressure difference.

[Weight ratio of hollow particles]

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 .

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.

After washing, 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 washing and drying is measured as A ₁ . 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%.

[Air tightness of continuous sheet material]

According to the JIS L 1096A method, the continuous sheet material is placed on the air permeability tester, and the air permeability is tested under a pressure difference of 125 Pa. Randomly select N=5 for testing, and average the test results as the final air tightness test result.

【Temperature difference on both sides of heat insulation and fireproof material】

Place the heat-insulating and fire-retardant material on the heating platform that has been stably heated. After the heating platform is stabilized, the set temperature is 600℃, which is recorded as T _1. Test the temperature change on the opposite side of the heat-insulating and fire-proof material and take the test for 20 minutes The maximum temperature inside is denoted as T ₂ , and the calculation of the temperature difference between the two sides of the heat-insulating and fire-resistant material is as follows:

The temperature difference between the two sides of the heat insulation and fireproof material (°C)=T ₁ -T ₂ .

【Insulation】

The greater the temperature difference between the two sides of the thermal insulation and fireproof material, the better the thermal insulation. The temperature difference between the two sides of the heat insulation and fireproof material is greater than 400℃, 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℃～400℃, 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.

【Compression Elasticity】

Use the SE-15 compression elasticity testing machine, in the standard mode, measure the sample thickness T ₁ when the pressure is 0.3 MPa, and then press it to 2 MPa. After standing for one minute, test the thickness T ₂ , then remove the pressure and leave it for one minute, then again Measure the sample thickness T ₃ when the pressure is 0.3 MPa, and the accuracy is 0.01 mm. The compressive elastic modulus is calculated according to the following formula: compressive modulus (%)=(T ₃ -T ₂ )/(T ₁ -T ₂ )×100%.

Before the description of the following embodiments, the materials involved in the embodiments will be described in detail.

[Fibers that make up porous materials]

<Non-melting fiber>

Using the pre-oxidized fiber "Pyron" (US registered trademark) produced by Zoltek, the length is 50mm, the fineness is 1.7 dtex, the high temperature shrinkage rate is 1.6%, and 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%.

【Hollow particles】

Using the aerogel powder produced by Shenzhen Zhongning Technology Co., Ltd., the model is AG-D. The thermal conductivity of the aerogel powder at room temperature is 0.018W/(m·K), the porosity is 90%, and the ratio The surface area is 800m ² /g.

【Heat storage material】

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.

【Sealing layer】

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%.

Example 1

60% by weight of 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 5-50μm 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 preparation On the upper and lower sides of the heat insulation layer, a layer of aluminum hydroxide powder is formed in the form of a film, that is, the heat storage layer; and the airtightness is 0.5cm ³ /cm ² /s and the thickness is 50 microns. The imide film was encapsulated from six sides, and the sealing material was fixed to the outer surface of the heat insulation layer by heating and pressing, and finally a heat insulation fireproof material was prepared, and its physical properties were evaluated and shown in Table 1.

Example 2

60% by weight of 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 needle punching is performed at a needle punch density of 300 needles/cm ² . 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 5-50μm 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, and its physical properties are evaluated and shown in Table 1.

Example 3

60% by weight of 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 150 needles/cm ² . A needle punched non-woven fabric with a thickness of 4.2 mm, a grammage of 300 g/cm ³ and a bulk density of 0.07 g/cm ³ was prepared as a fiber structure. The thermal conductivity of the fiber structure was measured to be 0.033W/(m· K). The pores in the fiber structure with a pore diameter between 5-50μm account for 35% 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 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.

Example 4

After mixing aluminum hydroxide powder with polyethylene hot melt adhesive particles, spread the mixed particles evenly on the upper and lower sides of the prepared heat insulation layer by sprinkling in to form a layer of aluminum hydroxide powder in the form of a film 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.

Example 5

Mix aluminum hydroxide powder and liquid polyimide flame-retardant resin uniformly to form a flame-retardant resin solution containing aluminum hydroxide, and then evenly coat it on the upper and lower sides of the needle punched non-woven fabric at 170°C After drying and curing, cool at room temperature, and form a layer of polyimide flame-retardant resin cured film with aluminum hydroxide powder attached to the upper and lower sides of the needle punched non-woven fabric as the heat storage layer, and finally make it distributed on both sides of the heat insulation layer 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.

Example 6

Sprinkle aluminum hydroxide powder into the composite material of needle-punched non-woven fabric and aerogel by means of physical filling to obtain a thermal insulation layer. At this time, the thermal insulation layer is the heat storage layer. 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.

Example 7

Mix aluminum hydroxide powder and liquid polyimide flame-retardant resin uniformly to form a flame-retardant resin solution containing aluminum hydroxide, and then evenly coat it on the upper and lower sides of the needle punched non-woven fabric at 170°C After drying and curing, cool at room temperature, and form a layer of polyimide acid flame-retardant resin cured film with aluminum hydroxide powder attached to the upper and lower sides of the needle punched non-woven fabric as the heat storage layer. Finally, the two heat insulation layers are distributed. The heat storage layer on the side 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.

Example 8

Mix aluminum hydroxide powder and liquid polyimide flame-retardant resin uniformly to form a flame-retardant resin solution containing aluminum hydroxide, and then evenly coat it on the upper and lower sides of the needle punched non-woven fabric at 170°C After drying and curing, cool at room temperature, and form a layer of polyimide acid flame-retardant resin cured film with aluminum hydroxide powder attached to the upper and lower sides of the needle punched non-woven fabric as the heat storage layer. Finally, the two heat insulation layers are distributed. The heat storage layer on the side 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 1. The physical properties were evaluated and shown in Table 1.

Example 9

60% by weight of 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 5-50μm 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 fiber structure after the hollow glass microbead dispersion is slightly pressurized to remove the excess dispersion on the surface, and then dried at low temperature to obtain the hollow glass microbead powder with an average diameter of 1000 microns attached to the inside of the needle punched non-woven fabric 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 polyethylene hot melt adhesive particles, the mixed particles are evenly spread by sprinkling in On the upper and lower sides of the heat insulation layer prepared above, a layer of magnesium hydroxide powder is formed in the form of a film, which is the heat storage layer; the airtightness is 0.5cm ³ /cm ² /s and the thickness is The 50-micron polyimide film is encapsulated on four sides from the upper and lower surfaces and the front and rear sides, and the sealing material is fixed on the outer surface of the heat insulation layer by heating and pressing. Finally, the heat insulation and fire protection material is prepared and evaluated Physical properties are shown in Table 1.

Example 10

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.

Example 11

After mixing potassium aluminum sulfate dodecahydrate 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 in the form of a film Potassium aluminum sulfate dodecahydrate powder layer is the heat storage layer; then a polyimide film with an air-tightness of 0.5cm ³ /cm ² /s and a thickness of 50 microns is used from the upper and lower surfaces as well as the front and back sides Four-sided encapsulation was carried out, and the sealing material was fixed on the outer surface of the thermal insulation layer by heating and pressing. The rest was the same as in Example 9. The thermal insulation and fireproof material was finally prepared, and its physical properties were evaluated and shown in Table 2.

Example 12

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 13

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.

Example 14

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.

Example 15

60% by weight of the flame-retardant viscose fiber with an LOI value of 28% and 40% by weight of glass fiber are used for blending, carding, and netting, and then needling processing at a needling density of 150 needles/cm ² to produce A needle-punched non-woven fabric with a thickness of 1.0mm, a weight of 300g/cm ³ and a bulk density of 0.30g/cm ³ was used as the fiber structure. The thermal conductivity of the fiber structure was measured to be 0.037W/(m·K ), the pores with a pore diameter of 5-50 μm in the fiber structure account for 45% of the total pores. The rest is the same as in Example 1. The physical properties of the heat insulating and fireproof material of the present invention were evaluated and shown in Table 2.

Example 16

Use 60% by weight of the flame-retardant viscose fiber with an LOI value of 34% and 40% by weight of glass fiber to blend, card, and lay the net, and then perform needle punching at a needle punch density of 400 needles/cm ² to produce A needle-punched non-woven fabric with a thickness of 1.0mm, a grammage of 300g/cm ³ and a bulk density of 0.30g/cm ³ was used as the fiber structure, and the thermal conductivity of the fiber structure was measured to be 0.032W/(m·K ), the pores with a pore diameter of 5-50 μm in the fiber structure account for 85% of the total pores. The rest is the same as in Example 1. The physical properties of the heat insulating and fireproof material of the present invention were evaluated and shown in Table 2.

Example 17

Using polyphenylene sulfide filaments and glass fibers for weaving, 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 5-50μm account for 58% of the total pores; the warp-knitted spacer fabric prepared above is immersed in a uniformly dispersed aerosol In the gel dispersion liquid, 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.

Example 18

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.

Comparative example 1

60% by weight of 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 needle punching is performed at a needle punch density of 600 needles/cm ² . 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 5-50μm 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.

Comparative example 2

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.

Comparative example 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.

Comparative example 4

60% by weight of 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 and 50 μm 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.

Table 1

Table 2

table 3

According to the above table:

(1) It can be seen from Examples 1-3 that under the same conditions, the smaller the bulk density of the porous material, and the greater the weight ratio of hollow particles in the heat-insulating layer, the better the heat-insulating properties of the obtained heat-insulating and fire-retardant material.

(2) 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.

(3) 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.

(4) It can be seen from Examples 9-11 that, under the same conditions, the weight ratio of the water released by the heat storage material when heated in Example 9 to the weight ratio of the heat-insulating and fire-proof material is not within the preferred range. The heat is slightly lower.

(5) It can be seen from Examples 1, 12, and 13, that under the same conditions, the larger the average diameter of the aerogel, the more voids in the heat-insulating and fire-proof material obtained, and the heat-insulating property is slightly lower.

(6) 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.

(7) 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.

(8) It can be seen from Comparative Example 1 and Example 1 that, under the same conditions, the bulk density of the porous material of the former is too large, the weight ratio of the aerogel in the heat insulating layer is drastically reduced, and the heat insulating property is deteriorated.

(9) It can be seen from Comparative Example 2 and Example 9 that under the same conditions, the average diameter of the hollow glass beads of the former is too large, the resulting material has more voids, and the heat insulation property is deteriorated.

(10) In Comparative Example 3, there is no porous material, the aerogel powder cannot be stably supported by the base material, and phenomena such as powder falling or uneven thermal insulation occur, and thermal insulation properties are deteriorated.

(11) In Comparative Example 4, there are no hollow particles and cannot block the transmission of the heat insulation amount, and the heat insulation property is deteriorated.

Claims

A heat-insulating fire-retardant material, characterized in that the heat-insulating fire-retardant material contains at least a heat-insulating layer, the heat-insulating layer contains a porous material and hollow particles, and 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 μm, and the thermal conductivity of the heat-insulating and fire-resistant material at room temperature after carbonization treatment is 0.040 W/(m·K) or less.
The heat-insulating fire-proof material according to claim 1, wherein the heat-insulating fire-proof material contains a sealing layer, the sealing layer is a continuous sheet material, and the sealing layer is located on at least two opposite sides of the insulating layer, The average total thickness of the sealing layer accounts for 0.5-90.0% of the total thickness of the heat-insulating and fire-proof material.
The heat-insulating fire-proof material according to claim 1 or 2, wherein the heat-insulating fire-proof material contains a heat storage material, the heat storage material is a hydrate or a metal hydroxide, and the heat storage material The weight ratio of the water released when heated is 2.0-25.0% relative to the weight of the heat insulating and fireproof material.
The heat-insulating fireproof material according to claim 3, wherein the heat storage material is a layered structure distributed on opposite sides of the heat-insulating layer, and the average thickness of the heat-storing layer is equal to the average thickness of the heat-insulating layer The ratio is 10 to 90%.
The heat-insulating fireproof material according to claim 3 or 4, wherein the heat storage material is dispersed in the heat-insulating layer.
The thermal insulation and fireproof material according to claim 3 or 4 or 5, characterized in that the heat storage material is dispersed in the sealing layer.
The heat insulating and fireproof material according to any one of claims 1 to 6, wherein the porous material is a fibrous structure.
The heat-insulating and fire-proof material according to claim 7, wherein the pores with a pore diameter between 5-50 μm in the fiber structure account for more than 50% of the total pores.
The heat insulating and fireproof material according to claim 7 or 8, wherein the thermal conductivity of the fiber structure is lower than 0.040 W/(m·K) at normal temperature.
The heat-insulating and fire-proof material according to claim 9, wherein the fiber structure is a non-woven fabric containing thermoplastic fibers having an LOI value of 28% or more and non-melting fibers.
The heat-insulating fire-proof material according to any one of claims 1 to 6, wherein the hollow particles are aerogel powder.
The heat-insulating fire-proof material according to claim 11, wherein the weight ratio of aerogel powder in the heat-insulating fire-proof material is 15% or more.
The heat-insulating and fire-proof material according to any one of claims 2 to 6, wherein the airtightness of the continuous sheet material is less than 20 cm 3 /cm 2 /s.
The heat insulation and fireproof material according to claim 13, wherein the continuous sheet material is a film material, a sheet formed of fiber textile, or a sheet formed of continuous resin.
The heat-insulating fire-proof material according to any one of claims 1-14, wherein the temperature difference between the two sides of the heat-insulating fire-proof material is greater than 300°C.
An application of the heat insulation and fireproof material according to any one of claims 1 to 15 in a battery.