Heat-conducting and flame-retardant material

Abstract

The present invention relates to a thermally conductive and flame-retardant material (101), wherein the thermally conductive and flame-retardant material (101) is in a liquid, colloidal, or semi-solid state and comprises: silicon dioxide, which constitutes 10-85% of the total weight; a reagent having crosslinking properties and foaming reactivity, which is mixed with the silicon dioxide; and a catalyst, which is a temperature-active or photoactive catalyst that, upon mixing with the reactant, triggers a foaming reaction of the reactant. The thermally conductive and flame-retardant material (101) has thermal conductivity properties before the foaming reaction of the reactant and exhibits flame-retardant properties after the foaming reaction of the reactant.

Description

AREA OF INVENTION

[0001] The present invention relates to a sealing material that serves to equip electronic components with explosion- and flame-retardant properties; in particular an application in a cover for battery cores that causes a foaming reaction which blocks the heat transfer from a battery core and thereby prevents overheating, explosion and extensive combustion. DESCRIPTION OF THE STATE OF THE TECHNOLOGY

[0002] The thermally conductive and flame-retardant material possesses properties that block heat transfer and prevent the spread of fire. This material is typically used in areas such as buildings, industrial facilities, and transportation to improve fire safety and fire resistance. Regarding the manufacturing processes and applied research on composite materials in the prior art, Chinese patent no. [number missing in original text] describes...CN116496628A the manufacture of raw materials for an insulating composite material comprising a substrate and a resin composition, wherein the resin composition contains the following components: 100 parts by weight of hydroxy-terminated polysiloxane, 5-20 parts by weight of vinylpolysiloxane, 20-50 parts by weight of hydrogenated polysiloxane, 0.1-5 parts by weight of sulfonylhydrazide foaming agent, 0.1-1 parts by weight of a desiccant, 1-20 parts by weight of a metal hydride and 5-50 parts by weight of silicon dioxide aerogel.After the resin composition has cured and foamed, a cross-linked network structure with uniform porosity is formed, giving the heat-insulating composite material excellent flame retardancy, low thermal conductivity, high temperature tolerance and thermal insulation properties that fully meet the requirements for building materials, electrical equipment, chemical equipment, energy storage and mechanical equipment or for use in the oil production industry.

[0003] Regarding the state of the art in curable silicone compositions, patent no. TW202311437A from Taiwan describes a cured material with high thixotropic properties, exhibiting excellent refractive index properties and transparency, and utilizing a curable silicone composition containing the following components: (A) an alkenyl-containing organopolysiloxane with at least two alkenyl groups per molecule; (B) a hydrogen-organic polysiloxane with at least two hydrogen atoms bonded to silicon atoms per molecule; (C) more than 3 wt% silicon dioxide-titanium oxide compound particles, based on the total mass of the composition; and (D) a catalyst for curing.

[0004] A foaming agent is a chemical substance or additive used in the manufacture of foam or foam material and is widely used in various industries and applications. It is typically used to modify the density, structure, and characteristic properties of a material. Regarding prior art research on manufacturing processes for aerogel-modified, heat-resistant polyurethane rigid foam, Chinese patent no. CN109232850A describes the dispersion of a heat-resistant aerogel composite in polyurethane to form a modified polyurethane foam. The compound heat-resistant flame retardant is a compound heat-resistant flame retardant produced by modifying aerogel powder with a heat-resistant phosphate ester flame retardant.The modified heat-resistant aerogel composite flame retardant is added to the rigid polyurethane foam (RPUF) and uniformly dispersed within it. After heating, curing, and aging, this results in a heat-resistant rigid polyurethane foam with flame-retardant properties and low thermal conductivity. The modified RPUF has a temperature resistance of up to 153°C, a thermal conductivity of less than 0.027 W / mK, an oxygen limit of at least 32%, and a compressive strength of 0.39–0.40 MPa.

[0005] Regarding the state of the art in manufacturing processes for high-performance fire-retardant phenolic foams, Chinese patent no. CN111732814B describes a high-performance fire-retardant phenolic foam produced from an inorganic flame-retardant material, phenolic resin, polyethylene glycol, an emulsifier, and a foaming agent, which are mixed together and combined with a curing agent. The inorganic flame-retardant material is obtained by mixing aluminum hydroxide, cerium dioxide, and silicon dioxide in a ratio of 10⁻²⁵ : 10⁻⁸ : 25. A specific ratio of organic and inorganic acids (the ratio of organic acids to inorganic acids is 1:3) acts as the curing agent. The resulting phenolic foam has a fire spread index of 0, and the smoke index is reduced to 35. Furthermore, the measured thermal conductivity is ≤0.023 W / mk.The high-performance, fire-retardant phenolic resin foam has good thermal insulation properties and meets the higher requirements for effective flame protection and fire retardancy. SUMMARY OF THE INVENTION

[0006] The present invention provides a thermally conductive and flame-retardant material, wherein the thermally conductive and flame-retardant material is in a liquid, colloidal, or semi-solid state and comprises: silicon dioxide comprising 10-85% of the total weight; a reagent exhibiting crosslinking properties and foaming reactivity, which is mixed with the silicon dioxide; and a catalyst, which is a temperature-active or photoactive catalyst that, upon mixing with the reactant, triggers a foaming reaction of the reactant. The thermally conductive and flame-retardant material exhibits thermal conductivity before the foaming reaction of the reactant and possesses flame-retardant properties after the foaming reaction.The average particle diameter of the silicon dioxide is 5 nm to 10 µm, and the reactant begins a foaming reaction at an ambient temperature above 130°C. At an ambient temperature above 160°C, the reactant initiates a foaming reaction that is complete within 30 seconds to 5 minutes. Before foaming occurs in the thermally conductive and flame-retardant material, the foaming reaction is complete after a foaming time of 6 seconds when the silicon dioxide constitutes 80% of the total weight. And before foaming occurs in the thermally conductive and flame-retardant material, the reaction is complete after a foaming time of 4 seconds when the silicon dioxide constitutes 40% of the total weight.The thermally conductive and flame-retardant material is used in the encapsulation of battery cores, as well as in the inner and outer casing materials of a battery core housing, prior to the reactant foaming reaction. A foaming reaction begins when the temperature reaches the reactant's reaction temperature, and once the reactant foaming reaction has occurred within the thermally conductive and flame-retardant material, heat transfer to the interior and exterior of the battery core is blocked. After the reactant foaming reaction within the thermally conductive and flame-retardant material, its flame retardancy is rated up to V0-5VA according to UL94. The material has a total thickness of 600 µm and provides thermal insulation at temperatures above 800°C.

[0007] The present invention achieves the effects of heat conduction, explosion protection, and flame retardancy and is particularly applicable for covering battery cores. The silicon dioxide material, prior to foaming, provides a heat-conducting effect that prevents overheating and explosion of the battery core. After a foaming reaction, the heat-conducting and flame-retardant material can block heat transfer from the battery core, thus preventing extensive combustion. The components and foaming properties of the present invention distinguish it from the prior art; moreover, its originality, progress, and practical effectiveness are undeniable.

[0008] For a better understanding of the objectives, structures, properties and effects, as well as the technology and methods used in the present invention and the effects achieved, a brief description of the accompanying drawings follows, with a subsequent detailed description of the preferred embodiments. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 shows a schematic cross-sectional view of a heat-conducting and flame-retardant material that is filled between a battery core and a first metal packaging material according to the present invention. Fig. Figure 2 shows a schematic cross-sectional view of the heat-conducting and flame-retardant material that is filled between a first metallic packaging material and a second metallic packaging material according to the present invention. DETAILED DESCRIPTION OF PREFERRED EXECUTION EXAMPLES

[0009] The following description explains the embodiments of the present invention by means of specific examples. Those skilled in the art can easily deduce further advantages and effects of the present invention from the content described in the description. The present invention may also have other specific embodiments to illustrate its performance and applications. Each detail described in the description may also be based on a different perspective and application, so that various types of modifications and changes can be made without departing from the spirit of the present invention.

[0010] The present invention provides a thermally conductive and flame-retardant material, wherein the thermally conductive and flame-retardant material is in a liquid, colloidal, or semi-solid state and comprises: silicon dioxide, which constitutes 10-85% of the total weight; a reagent exhibiting crosslinking properties and foaming reactivity, which is mixed with the silicon dioxide; and a catalyst, which is a temperature-active or photoactive catalyst. The catalyst is mixed with the reactant to initiate a foaming reaction of the reactant. Before the foaming reaction of the reactant, the thermally conductive and flame-retardant material exhibits thermal conductivity, and after the foaming reaction of the reactant, it exhibits flame-retardant properties.

[0011] The average particle diameter of the silicon dioxide is 5 nm to 10 µm, and the reactant begins a foaming reaction at an ambient temperature above 130°C. At an ambient temperature above 160°C, the reactant initiates a foaming reaction that is complete within 30 seconds to 5 minutes. Before foaming occurs within the thermally conductive and flame-retardant material, the reaction is complete after a foaming time of 6 seconds if the silicon dioxide constitutes 80% of the total weight. If the silicon dioxide constitutes 40% of the total weight, the foaming reaction is complete after a foaming time of 4 seconds.

[0012] Before the reactant foams in the thermally conductive and flame-retardant material, the material can be used for coating battery cores as well as for inner and outer covering materials for a battery core casing. When the temperature reaches the reaction temperature for the reactant to initiate a foaming reaction in the thermally conductive and flame-retardant material, the foaming reaction blocks heat transfer to the interior and exterior of the battery core. After the reactant foams in the thermally conductive and flame-retardant material, the flame retardancy is rated up to V0-5VA according to UL94. After the reactant foams in the thermally conductive and flame-retardant material, its total thickness is 600 µm and provides thermal insulation at temperatures above 800°C.In the test of the thermal insulation temperature, one side of a thin disc of the thermally conductive and flame-retardant material with a total thickness of 600 µm was heated and a thermometer was used to check whether the temperature on the other side of the thin disc rose.

[0013] To enable the examination committee to better understand the practical applications of the present invention, examples of its use in thermal conductivity and explosion protection of battery cores are given. Fig. Figure 1 shows a schematic cross-sectional view of a thermally conductive and flame-retardant material that is filled between a battery core and a first metal packaging material according to the present invention, wherein a thermally conductive and flame-retardant material 101 of the present invention is filled between a battery core 201 and a first metal packaging material 301. The first metal packaging material 301 is an aluminum casing, aluminum foil, or a stainless steel casing, and the thermally conductive and flame-retardant material 101 completely covers the battery core 201. When the battery core 201 generates heat during normal use, the thermally conductive and flame-retardant material 101, in its unfoamed state, can adequately dissipate the heat energy, thereby achieving heat dissipation and a cooling effect of the battery core 201.And if the battery core 201 generates abnormal heat, the reactant initiates a foaming reaction at an ambient temperature above 130°C. This foaming reaction is completed within 30 seconds to 5 minutes, after which the thermally conductive and flame-retardant material 101 can block heat transfer from the battery core 201 to the outside and prevent extensive combustion. In other words, simply covering the internal smoldering of the individual abnormal battery core 201 with the foamed thermally conductive and flame-retardant material 101, the foamed air chambers within the material block heat transfer after the material has foamed. This prevents the abnormal battery core 201 from heating other battery cores or other electronic components.

[0014] The Fig.Figure 2 shows a schematic cross-sectional view of the thermally conductive and flame-retardant material that is filled between a first metal packaging material and a second metal packaging material according to the present invention, showing the thermally conductive and flame-retardant material 101 that is filled between the first metal packaging material 301 and a second metal packaging material 302 according to the present invention. The first metal packaging material 301 and the second metal packaging material 302 are aluminum trays, aluminum foils, or stainless steel trays, wherein the thermally conductive and flame-retardant material 101 completely covers the second metal packaging material 302, which surrounds the battery core 201.When the battery core 201 generates heat during normal use, the thermally conductive and flame-retardant material 101, in its unfoamed state, can adequately dissipate the heat energy, thus achieving heat dissipation and a cooling effect for the battery core 201. If the battery core 201 generates abnormally high heat, the reactant initiates a foaming reaction at an ambient temperature exceeding 130°C. This foaming reaction is completed within 30 seconds to 5 minutes, after which the thermally conductive and flame-retardant material 101 blocks heat transfer from the battery core 201 to the outside, preventing extensive combustion.In other words, by simply covering the internal smoldering of the individual abnormal battery core 201 with the foamed thermally conductive and flame-retardant material 101, after the foaming of the thermally conductive and flame-retardant material 101, the heat transfer through the foamed air chambers of the material is blocked, thus preventing the abnormal battery core 201 from further heating other battery cores or other electronic components.

[0015] The present invention undoubtedly creates a thermally conductive and flame-retardant material that enables heat conduction, explosion protection and flame retardancy, which is particularly useful in the covering of battery cores.

[0016] The components and foam-technical properties of the present invention distinguish it from the prior art; moreover, its originality, its progress and its practical effectiveness are unmistakable, which enables effective improvements over the shortcomings of the prior art.

[0017] In summary, the silicon dioxide material in the unfoamed, thermally conductive, and flame-retardant material exhibits a thermally conductive effect and also enables a foaming reaction to prevent overheating and explosion of a battery core by blocking heat transfer from the battery core and preventing extensive combustion. Regarding the overall components and the foaming mechanism of the present invention, it offers both thermal conductivity and flame-retardant effects that have not been observed in comparable products to date. Furthermore, the content of this patent specification was not publicly disclosed prior to the present application, so the essential elements required for a new patent are clearly fulfilled. Accordingly, a patent application is hereby proposed.

[0018] It is understood that the embodiments described here merely represent the principles of the present invention and that several modifications can be made by a person skilled in the art without deviating from the spirit and scope of the present invention as set out in the attached claims. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] CN 116496628A

[0002] TW 202311437A

[0003] CN 109232850A

[0004] CN 111732814B

[0005]

Claims

[1] A heat-conducting and flame-retardant material (101), wherein the heat-conducting and flame-retardant material (101) is in a liquid state, a colloidal state or a semi-solid state, comprising: Silicon dioxide, which makes up 10-85% of the total weight; a reactant which has crosslinking properties and foaming reactivity and is mixed with the silicon dioxide; and a catalyst which is a temperature-active or photoactive catalyst which, when mixed with the reactant, triggers a foaming reaction of the reactant; the thermally conductive and flame-retardant material (101) has thermal conductivity before a foaming reaction of the reactant and is provided with flame-retardant properties after a foaming reaction of the reactant. [2] The heat-conducting and flame-retardant material (101) according to claim 1, wherein the average particle diameter of the silicon dioxide is 5 nm-10 µm. [3] The thermally conductive and flame-retardant material (101) of claim 1, wherein the reactant triggers a foaming reaction at an ambient temperature of more than 130°C. [4] The thermally conductive and flame-retardant material (101) of claim 1, wherein the reactant initiates a foaming reaction at an ambient temperature of more than 160°C, which is completed in 30 seconds to 5 minutes. [5] The thermally conductive and flame-retardant material (101) according to claim 1, wherein the silicon dioxide accounts for 80% of the total weight before a foaming reaction of the reactant in the thermally conductive and flame-retardant material (101) takes place, and the foaming reaction is completed after a foaming time of 6 seconds. [6] The thermally conductive and flame-retardant material (101) according to claim 1, wherein the silicon dioxide accounts for 40% of the total weight before a foaming reaction of the reactant in the thermally conductive and flame-retardant material (101) takes place, and the foaming reaction is completed after a foaming time of 4 seconds. [7] The thermally conductive and flame-retardant material (101) according to claim 1, wherein the thermally conductive and flame-retardant material (101) is used in the cover of battery cores (201) and in inner and outer cover materials for a battery core casing prior to a foaming reaction of the reactant. [8] The heat-conductive and flame-retardant material (101) according to claim 1, wherein the heat-conductive and flame-retardant material (101) is used in the cover of battery cores (201) and in inner and outer cover materials for a battery core casing before a foaming reaction of the reactant occurs; a foaming reaction starts when the temperature reaches the reaction temperature of the reactant, and after the foaming reaction of the reactant occurs in the heat-conductive and flame-retardant material (101), heat transfer to an inside and outside of the battery core (201) is blocked. [9] The heat-conducting and flame-retardant material (101) according to claim 1, wherein after the foaming reaction of the reactant in the heat-conducting and flame-retardant material (101), its flame retardancy is rated up to V0-5VA according to UL94. [10] The heat-conducting and flame-retardant material (101) according to claim 1, wherein, after a foaming reaction of the reactant in the heat-conducting and flame-retardant material (101), its total thickness is 600 µm and ensures thermal insulation at temperatures above 800°C.

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