Heat-conducting flame-retardant material

Abstract

To provide a heat-conducting flame-retardant material that can foam before battery cells and the like, overheat and explode, thereby blocking heat transfer and preventing combustion when applied to the coating of battery cells and the like.SOLUTION: There is provided a heat-conducting flame-retardant material, wherein the heat-conducting flame-retardant material is a liquid state, colloidal state, or a semisolid state, and comprises silicon dioxide, a reactant and a catalyst. The silicon dioxide accounts for 10 to 85% of the entire weight. The reactant has crosslinking properties and foaming reactivity and is mixed with the silicon dioxide. The catalyst is a temperature active or photoactive catalyst, and when mixed with a reactant, it triggers a foaming reaction of the reactant. The heat-conducting flame-retardant material has a heat conductivity before a foaming reaction of the reactant occurs, and has flame retardancy after a foaming reaction of the reactant occurs.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an explosion-proof and flame-retardant sealing material for electronic components, and in particular to a thermally conductive flame-retardant material suitable for covering battery cells, which can foam to block heat transfer and prevent combustion before the battery cells overheat and explode. [Background technology]

[0002] Thermally conductive flame retardant materials are materials that have the properties to inhibit the conduction of thermal energy and resist the spread of fire. Such materials are typically used in construction, industrial facilities, transportation and other areas to improve fire safety and fire performance.

[0003] As a research on conventional heat insulating composite materials and their preparation methods and applications, for example, Patent Document 1 discloses a heat insulating composite material in which the raw materials for producing the material include a base material and a resin composition, and the resin composition includes, by weight, 100 parts by weight of hydroxyl-terminated polysiloxane, 5 to 20 parts by weight of vinyl-group polysiloxane, 20 to 50 parts by weight of hydrogen-containing polysiloxane, 0.1 to 5 parts by weight of sulfonyl hydrazide blowing agent, 0.1 to 1 part by weight of desiccant, 1 to 20 parts by weight of metal hydride, and 5 to 50 parts by weight of silicon dioxide aerogel. Through the component design and formulation of the resin composition, a crosslinked network structure and a uniform porous structure are formed after the resin composition is cured and foamed, which gives the heat insulating composite material excellent flame retardancy, low thermal conductivity coefficient, high temperature resistance and heat insulation, making it fully suitable for applications such as building materials, electrical products, chemical equipment, energy storage equipment, mechanical equipment and oil development.

[0004] Furthermore, as an example of research into curable silicone compositions, Patent Document 2 discloses a cured product that has high thixotropy and exhibits excellent refractive index and transparency. This is applied to the fields mentioned above by a curable silicone composition containing the following components: (A) an alkenyl-containing organopolysiloxane having at least two alkenyl groups per molecule, (B) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, (C) silica-titania composite oxide particles in an amount of 3 mass % or more relative to the total mass of the composition, and (D) a curing catalyst.

[0005] Blowing agents are chemicals or additives used in the production of foam or foam-like materials. They are widely used in a variety of industries and applications, typically to modify the density, structure, and properties of the material. As a conventional study on aerogel-modified heat-resistant rigid polyurethane foam plastics and a method for producing the same, for example, Patent Document 3 discloses a method in which an aerogel composite heat-resistant flame retardant is dispersed in a polyurethane body to modify it, and then a polyurethane foam is formed.

[0006] This composite heat-resistant flame retardant is a composite heat-resistant flame retardant formed by modifying aerogel powder with a phosphate ester-based heat-resistant flame retardant. The modified aerogel composite heat-resistant flame retardant is added to polyurethane foam (RPUF), and the composite heat-resistant flame retardant is uniformly dispersed throughout the RPUF body. After heating, curing, and aging, a heat-resistant, flame-retardant, low-thermal conductivity rigid polyurethane foam is obtained. After modification with this material, the RPUF has a heat resistance of up to 153°C, a thermal conductivity of less than 0.027 W / m·K, a limit oxygen index of 32% or more, and a compressive strength of 0.39 to 0.40 MPa.

[0007] As a conventional study on high-performance fire-resistant and flame-retardant phenolic foam and its manufacturing method, for example, the high-performance fire-resistant and flame-retardant phenolic foam disclosed in Patent Document 4 is manufactured by mixing inorganic fire-retardant material with phenolic resin, polyethylene glycol, emulsifier, and foaming agent, and then adding a curing agent. The inorganic fire-retardant material is obtained by mixing aluminum hydroxide, cerium dioxide, and silicon dioxide according to a ratio of 10-25:5-10:8-25, and organic acid and inorganic acid are mixed in a specific ratio (ratio of organic acid:inorganic acid is 1:3) as a curing agent. The measured flame spread index of the manufactured phenolic foam is 0, and the smoke index is reduced to 35. At the same time, the measured thermal conductivity is ≦0.023 W / m·k or less, and the high-performance fire-resistant and flame-retardant phenolic foam has good heat retention performance and achieves a higher fire and flame retardant effect. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] People's Republic of China Patent Publication No. CN116496628A Specification [Patent Document 2] Taiwan Patent Publication No. TW202311437A [Patent Document 3] People's Republic of China Patent Publication No. CN109232850A Specification [Patent Document 4] People's Republic of China Patent Publication No. CN111732814B Specification Summary of the Invention [Problem to be solved by the invention]

[0009] The problem to be solved by the present invention is to provide a thermally conductive flame retardant material that, when applied to cover battery cells or the like, can foam to block heat transfer and prevent combustion before the battery cells or the like overheat and explode. [Means for solving the problem]

[0010] The thermally conductive flame-retardant material of the present invention is in a liquid, colloidal or semi-solid state, and comprises silicon dioxide, a reactant and a catalyst, the silicon dioxide accounts for 10 to 85% by weight of the total, the reactant has crosslinking properties and foaming reactivity and is mixed with the silicon dioxide, the catalyst is a temperature-responsive or photoresponsive catalyst and is mixed with the reactant to catalyze a foaming reaction of the reactant, and the thermally conductive flame-retardant material has thermal conductivity before the foaming reaction of the reactant and has flame retardancy after the foaming reaction of the reactant.

[0011] In one embodiment, the average particle size d of the silicon dioxide is 5 nm to 10 μm.

[0012] In one embodiment, the reactants initiate a foaming reaction when the environmental temperature exceeds 130°C.

[0013] In one embodiment, the reactant starts a foaming reaction when the environmental temperature exceeds 160° C., and the foaming reaction is completed within 30 seconds to 5 minutes.

[0014] In one embodiment, before the foaming reaction of the reactants, silicon dioxide accounts for 80% by weight of the total, and the foaming reaction is completed in 6 seconds.

[0015] In one embodiment, before the foaming reaction of the reactants, silicon dioxide accounts for 40% by weight of the total, and the foaming reaction is completed in 4 seconds.

[0016] In one embodiment, the thermally conductive flame retardant material is applied to the coating of the battery cells and the coating materials inside and outside the battery cell housing before the reactants undergo a foaming reaction.

[0017] In one embodiment, the thermally conductive flame-retardant material is applied to the coating of the battery cell and the coating material inside and outside the battery cell housing before the foaming reaction of the reactant, and starts the foaming reaction when the temperature reaches the reaction temperature of the reactant, and after the foaming reaction of the reactant of the thermally conductive flame-retardant material, the temperature transfer between the inside and outside of the battery cell is blocked.

[0018] In one embodiment, the flame retardancy of the thermally conductive flame retardant material after the foaming reaction of the reactants is higher than grade UL94, and can reach V0-5VA.

[0019] In one embodiment, the thermally conductive flame-retardant material has a total thickness of 600 μm and an insulating temperature of higher than 800° C. after the foaming reaction of the reactants. Effect of the Invention

[0020] The thermally conductive flame-retardant material of the present invention exhibits the effects of heat conduction, explosion prevention and combustion inhibition, and is particularly applicable to covering battery cells, etc., where the silicon dioxide material before foaming exhibits a heat conductive effect, causing a foaming reaction before the battery cells, etc. overheat and explode, and after foaming, it can block the temperature transfer to the battery cells, etc., and prevent combustion. [Brief description of the drawings]

[0021] [Figure 1] FIG. 2 is a cross-sectional view showing a state in which a thermally conductive, flame-retardant material is filled between a battery cell and a first metal packaging material, according to an embodiment of the present invention. [Diagram 2] 1 is a cross-sectional view showing a state in which a thermally conductive, flame-retardant material is filled between a first metal packaging material and a second metal packaging material, illustrating an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Needless to say, the present invention is not limited to the embodiments, and the details of the embodiments described below can be modified and changed without departing from the gist of the present invention.

[0023] The thermally conductive flame-retardant material of the present invention is in a liquid, colloidal or semi-solid state, and contains silicon dioxide, a reactant and a catalyst, with the silicon dioxide occupying 10 to 85% by weight of the total. The reactant has crosslinking and foaming reactivity, and is mixed with silicon dioxide. The catalyst is a temperature-responsive or light-responsive catalyst that is mixed with the reactants to catalyze the foaming reaction of the reactants. The thermally conductive, flame retardant material is thermally conductive prior to the foaming reaction of the reactants and is flame retardant after the foaming reaction of the reactants.

[0024] The average particle size d of the silicon dioxide is 5 nm to 10 μm. As an example, the reactants start a foaming reaction when the environmental temperature exceeds 130°C. As another example, the reactant starts a foaming reaction when the environmental temperature exceeds 160° C., and the foaming reaction is completed within 30 seconds to 5 minutes. As yet another example, before the reactants of the thermally conductive flame retardant material start to foam, silicon dioxide accounts for 80% by weight of the total, and the foaming reaction is completed in 6 seconds. As yet another example, before the reactants of the thermally conductive flame retardant material start to foam, silicon dioxide accounts for 40% by weight of the total, and the foaming reaction is completed in 4 seconds.

[0025] The thermally conductive, flame retardant material is applied to the coating of the battery cells and to the coating materials inside and outside the battery cell housing before the reactants undergo a foaming reaction. After the thermally conductive flame-retardant material is applied to the coating of the battery cell and the coating materials inside and outside the battery cell housing, the reactant will start a foaming reaction when the temperature reaches the reaction temperature of the reactant, and after the foaming reaction of the reactant, the thermally conductive flame-retardant material will block the temperature transfer between the inside and outside of the battery cell.

[0026] After the foaming reaction of the reactants, the flame retardancy of the thermal conductive flame retardant material is higher than grade UL94, and can reach V0~5VA. After the foaming reaction of the reactants, the thermally conductive flame-retardant material has a total thickness of 600 μm and an adiabatic temperature of more than 800° C. The adiabatic temperature is obtained by heating one side of a sheet of the thermally conductive flame-retardant material having a total thickness of 600 μm and measuring the temperature of the other side to test whether there is a temperature increase.

[0027] In order to help users better understand the actual application of thermally conductive flame-retardant materials, we will take an example of their application in battery cell thermal conduction and explosion protection. FIG. 1 shows the thermally conductive, flame-retardant material of the present invention filled between a battery cell and a first metal packaging material. The thermally conductive flame-retardant material 101 is filled between the battery cell 201 and the first metal packaging material 301. The first metal packaging material 301 is an aluminum housing, an aluminum foil, or a stainless steel housing, and the thermally conductive flame-retardant material 101 completely covers the battery cell 201.

[0028] When the battery cell 201 generates heat under normal use, the thermally conductive flame-retardant material 101 in the unfoamed state can sufficiently release the thermal energy to achieve the heat dissipation and temperature reduction effect of the battery cell 201. When the battery cell 201 generates abnormal heat, the reactant starts a foaming reaction at an environmental temperature above 130° C., and the foaming reaction is completed within a short period of 30 seconds to 5 minutes. After foaming, the thermally conductive flame-retardant material 101 can block the transfer of the temperature of the battery cell 201 to the outside, and prevent combustion. In other words, the single abnormal battery cell 201 will simply smolder inside the foamed thermally conductive flame-retardant material 101, and the foaming chamber formed by the foamed thermally conductive flame-retardant material 101 will block heat transfer, preventing the single abnormal battery cell 201 from continuing to spread fire to other battery cells or electronic components.

[0029] FIG. 2 shows a state in which the thermally conductive, flame-retardant material of the present invention is filled between a first metal packaging material and a second metal packaging material. A thermally conductive, flame-retardant material 101 is filled between a first metal packaging material 301 and a second metal packaging material 302 . The first metal packaging material 301 and the second metal packaging material 302 are aluminum housing, aluminum foil, or stainless steel housing, and the thermally conductive and flame-retardant material 101 completely covers the second metal packaging material 302 around the battery cell 201 .

[0030] When the battery cell 201 generates heat under normal use, the thermally conductive flame-retardant material 101 in the unfoamed state can sufficiently release the thermal energy to achieve the heat dissipation and temperature reduction effect of the battery cell 201. When the battery cell 201 generates abnormal heat, the reactant starts a foaming reaction at an environmental temperature of over 130° C., and the foaming reaction is completed within a short period of time of 30 seconds to 5 minutes. The foamed thermally conductive flame-retardant material 101 can block the transfer of the temperature of the battery cell 201 to the outside, and prevent combustion. In other words, the single abnormal battery cell 201 will simply smolder inside the foamed thermally conductive flame-retardant material 101, and the foaming chamber formed by the foamed thermally conductive flame-retardant material 101 will block heat transfer, preventing the single abnormal battery cell 201 from continuing to spread fire to other battery cells or electronic components.

[0031] To sum up, in the above embodiment, when the thermally conductive flame-retardant material is not foamed, the silicon dioxide material in the thermally conductive flame-retardant material exerts a thermal conductive effect, and a foaming reaction occurs before the battery cell overheats and explodes, so as to block the temperature transfer of the battery cell and prevent combustion.

[0032] The above is merely a description of the embodiments of the present invention, and the scope of the present invention is not limited thereto. All changes and modifications that do not depart from the scope of the claims are included within the scope of the present invention. [Explanation of symbols]

[0033] 101 Thermally conductive flame retardant materials 201 Battery Cells 301 First metal packaging material 302 Second metal packaging material

Claims

1. A thermally conductive, flame retardant material, the thermally conductive, flame retardant material being in a liquid, colloidal, or semi-solid state, comprising silicon dioxide, a reactant, and a catalyst; The silicon dioxide accounts for 10 to 85% by weight of the total, The reactant has crosslinking and foaming reactivity and is mixed with the silicon dioxide; the catalyst is a temperature-responsive or photoresponsive catalyst, and is mixed with the reactant to catalyze a foaming reaction of the reactant; The thermally conductive, flame-retardant material has thermal conductivity before a foaming reaction of the reactants and has flame retardancy after a foaming reaction of the reactants.

2. The thermally conductive flame-retardant material according to claim 1, characterized in that the average particle size d of the silicon dioxide is 5 nm to 10 μm.

3. 2. The thermally conductive flame-retardant material according to claim 1, wherein the reactant initiates a foaming reaction when the environmental temperature exceeds 130°C.

4. 2. The thermally conductive flame-retardant material according to claim 1, wherein the reactant starts a foaming reaction when the environmental temperature exceeds 160° C., and the foaming reaction is completed within 30 seconds to 5 minutes.

5. 2. The thermally conductive flame-retardant material according to claim 1, wherein the silicon dioxide accounts for 80% by weight of the total before the foaming reaction of the reactants, and the foaming reaction is completed in 6 seconds.

6. 2. The thermally conductive flame-retardant material according to claim 1, characterized in that before the foaming reaction of the reactants, silicon dioxide accounts for 40% wt of the total, and the foaming reaction is completed in 4 seconds.

7. The thermally conductive flame-retardant material according to claim 1, characterized in that, before the reactants undergo a foaming reaction, the thermally conductive flame-retardant material is applied to a coating of a battery cell and a coating material inside and outside a battery cell housing.

8. 2. The thermally conductive flame-retardant material according to claim 1, characterized in that before a foaming reaction of the reactant, the thermally conductive flame-retardant material is applied to a coating of a battery cell and a coating material inside and outside a battery cell housing, and starts a foaming reaction when a temperature reaches a reaction temperature of the reactant; and after the foaming reaction of the reactant, temperature transfer between the inside and outside of the battery cell is blocked.

9. 2. The thermally conductive flame-retardant material according to claim 1, wherein the flame retardancy of the thermally conductive flame-retardant material after the foaming reaction of the reactants is higher than grade UL94, and reaches V0-5VA.

10. 2. The thermally conductive flame-retardant material according to claim 1, wherein the thermally conductive flame-retardant material has a total thickness of 600 μm and an adiabatic temperature of higher than 800° C. after the foaming reaction of the reactants.

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