Aerogel fire extinguishing agent and preparation method thereof

Abstract

The invention discloses an aerogel fire extinguishing agent and a preparation method thereof, and the aerogel fire extinguishing agent comprises the following components by mass: 2-10 parts of inorganic aerogel powder, 3-5 parts of a fluorocarbon surfactant, 4-6 parts of a hydrocarbon surfactant, 6-8 parts of a foaming agent, 4-10 parts of a lithium ion battery flame retardant, 8-13 parts of an organic solvent, 1-10 parts of an antifreeze agent, 0.05-1 part of a foam stabilizer, and the balance of water. The obtained aerogel fire extinguishing agent has high viscosity, when the aerogel fire extinguishing agent is sprayed on the lithium ion battery, a gas-liquid-solid three-phase isolation layer can be rapidly formed, the three-phase isolation layer adheres to the surface of the battery, oxygen is isolated, fire disasters can be rapidly extinguished, and meanwhile reburning is restrained.

Description

Technical Field

[0001] The invention relates to the field of fire extinguishing agent processing, and in particular to an aerogel fire extinguishing agent and a preparation method thereof. Background Art

[0002] As a representative of clean energy, lithium-ion batteries have the characteristics of high conversion efficiency and no pollution. They are currently widely used in the fields of mobile Internet, electric vehicles, and aerospace. While lithium-ion batteries are widely used, related fire accidents occur frequently, and the fire hazard has received widespread attention. The fire hazard of lithium-ion batteries mainly comes from its battery design defects and abuse during use. The direct cause of lithium-ion battery combustion is thermal runaway caused by the heat generation rate of the battery core being greater than the heat dissipation rate of the lithium-ion battery to the external environment. Once a lithium-ion battery has thermal runaway, if it is not promptly extinguished and controlled, it will quickly cause the surrounding battery modules to burn or explode, seriously threatening people's lives and property.

[0003] Lithium-ion battery fires are quite different from traditional fires. Once a lithium-ion battery has thermal runaway, it will burn with the characteristics of three types of fires: A, B, and C. Therefore, lithium-ion battery fires burn quickly and last for a long time. Not only is the combustion temperature high, but it is also highly toxic. However, the automatic fire extinguishing systems configured by most domestic manufacturers and warehouses currently use water as the main extinguishing agent. Although traditional water-based fire extinguishing agents can reduce the temperature, once the spraying stops, the battery is very likely to have thermal runaway again. Dry powder fire extinguishing agents and gas fire extinguishing agents have poor cooling effects and are also difficult to be effective. Summary of the invention

[0004] The main purpose of the present invention is to propose an aerogel fire extinguishing agent and a preparation method thereof, aiming to solve the problem that the battery is very likely to have thermal runaway again, and the cooling effect of dry powder fire extinguishing agents and gas fire extinguishing agents is poor and is also difficult to be effective.

[0005] To achieve the above purpose, the present invention provides an aerogel fire extinguishing agent, which includes the following components by mass: 2-10 parts of inorganic aerogel powder, 3-5 parts of fluorocarbon surfactant, 4-6 parts of hydrocarbon surfactant, 6-8 parts of foaming agent, 4-10 parts of lithium ion battery flame retardant, 8-13 parts of organic solvent, 1-10 parts of antifreeze agent, 0.05-1 part of foam stabilizer and balance water.

[0006] In some embodiments, the inorganic aerogel powder includes at least one of silica aerogel, alumina aerogel, zirconium dioxide aerogel, silica-alumina binary aerogel, and silica-zirconium binary aerogel.

[0007] In some embodiments, the fluorocarbon surfactant includes FS-50, Cap1470, Cap1157, or Cap1440.

[0008] In some embodiments, the hydrocarbon surfactant includes at least one of disodium lauryl sulfosuccinate, disodium fatty alcohol polyoxyethylene ether (3) sulfosuccinate, disodium acid monoethanolamide sulfosuccinate, potassium monododecyl phosphate, alcohol ether phosphate, sodium lauryl amphoacetate, potassium lauryl ether phosphate, and ammonium fatty alcohol polyoxyethylene ether sulfate.

[0009] In some embodiments, the foaming agent includes one of sodium lauryl sulfate, cocamidopropyl betaine, sodium dodecylbenzene sulfonate, lauroamidopropyl betaine, and cocamidopropyl hydroxysulfonate.

[0010] In some embodiments, the lithium ion battery flame retardant includes azobisisobutylimidazoline hydrochloride.

[0011] In some embodiments, the organic solvent includes at least one of diethylene glycol monobutyl ether, ethanol, ethylene glycol, and polyethylene glycol.

[0012] In some embodiments, the antifreeze agent is one or more of methanol, sodium chloride, calcium chloride, magnesium chloride, dimethyl sulfoxide and saline; and / or,

[0013] The foam stabilizer includes at least one of carbomer, alginate or sodium carboxymethyl cellulose.

[0014] The present invention also provides a method for preparing an aerogel fire extinguishing agent, wherein the preparation of the aerogel fire extinguishing agent comprises the following steps:

[0015] S10, adding a fluorocarbon surfactant, a hydrocarbon surfactant, a foaming agent and an inorganic aerogel powder into water, and stirring evenly to obtain a mixed solution A;

[0016] S20, stirring and dissolving the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and water to obtain a mixed solution B;

[0017] S30, stirring and mixing the mixed solution B and the mixed solution A, and adding the remaining water to obtain an aerogel fire extinguishing agent.

[0018] In step S10, the stirring speed is 400-500 rpm; and / or,

[0019] In step S10, the stirring time is 1.5-2h; and / or,

[0020] In step S20, the stirring speed is 600-700 rpm; and / or,

[0021] In step S20, the stirring time is 0.5h; and / or,

[0022] In step S30, the stirring speed is 800-1000 rpm; and / or,

[0023] In step S30, the stirring time is 2 hours.

[0024] The present invention provides an aerogel fire extinguishing agent and a preparation method thereof, which is prepared by compounding 2-10 parts of inorganic aerogel powder, 3-5 parts of fluorocarbon surfactant, 4-6 parts of hydrocarbon surfactant, 6-8 parts of foaming agent, 4-10 parts of lithium ion battery flame retardant, 8-13 parts of organic solvent, 1-10 parts of antifreeze agent, 0.05-1 part of foam stabilizer and the balance of water. The inorganic aerogel powder in the aerogel fire extinguishing agent has extremely high porosity, is filled with lithium ion battery flame retardant and solvent water, can continuously cool the lithium ion battery, block the propagation of thermal runaway, and the lithium ion battery flame retardant can restore the thermal runaway when the lithium ion battery burns. The reactants produced by the fire extinguisher are controlled, and the anions therein can capture the free radicals produced during combustion to prevent the combustion of the battery. The fluorocarbon surfactant used does not contain perfluorooctane sulfonic acid (PFOS), which can greatly reduce the surface tension of water without causing pollution to the environment. The use of hydrocarbon surfactants and foaming agents can enable the fire extinguishing agent to produce a large amount of stable foam more quickly, which can quickly cover the surface of the battery, reduce the temperature, and isolate oxygen. The obtained aerogel fire extinguishing agent has a large viscosity. When sprayed on a lithium-ion battery, it can quickly form a "gas-liquid-solid" three-phase insulation layer, adhere to the battery surface, isolate oxygen, and can quickly extinguish the fire while suppressing re-ignition. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0026] Figure 1 This is a flow chart of the aerogel fire extinguishing agent provided in Example 1 of the present invention.

[0027] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] To make the purpose, technical scheme and advantages of the embodiment of the present invention clearer, the technical scheme in the embodiment of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiment, it is carried out according to the normal conditions or the conditions recommended by the manufacturer. If the reagents or instruments used do not specify the manufacturer, they are all conventional products that can be purchased commercially. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes, taking "A and / or B" as an example, including scheme A, or scheme B, or schemes that A and B meet at the same time. In addition, the technical schemes between the various embodiments can be combined with each other, but must be based on the ability of ordinary technicians in the field to achieve. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that the combination of such technical solutions does not exist, and is not within the scope of protection required by the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present invention.

[0029] Lithium-ion battery fires are quite different from traditional fires. Once a lithium-ion battery has thermal runaway, it will burn with the characteristics of three types of fires: A, B, and C. Therefore, lithium-ion battery fires burn quickly and last for a long time. Not only is the combustion temperature high, but it is also highly toxic. However, the automatic fire extinguishing systems configured by most domestic manufacturers and warehouses currently use water as the main extinguishing agent. Although traditional water-based fire extinguishing agents can reduce the temperature, once the spraying stops, the battery is very likely to have thermal runaway again. Dry powder fire extinguishing agents and gas fire extinguishing agents have poor cooling effects and are also difficult to be effective.

[0030] In the present invention, an aerogel fire extinguishing agent is proposed, which includes the following mass components: 2-10 parts of inorganic aerogel powder, 3-5 parts of fluorocarbon surfactant, 4-6 parts of hydrocarbon surfactant, 6-8 parts of foaming agent, 4-10 parts of lithium ion battery flame retardant, 8-13 parts of organic solvent, 1-10 parts of antifreeze agent, 0.05-1 parts of foam stabilizer and balance water.

[0031] The present invention provides an aerogel fire extinguishing agent and a preparation method thereof, which is prepared by compounding 2-10 parts of inorganic aerogel powder, 3-5 parts of fluorocarbon surfactant, 4-6 parts of hydrocarbon surfactant, 6-8 parts of foaming agent, 4-10 parts of lithium ion battery flame retardant, 8-13 parts of organic solvent, 1-10 parts of antifreeze agent, 0.05-1 part of foam stabilizer and the balance of water. The inorganic aerogel powder in the aerogel fire extinguishing agent has extremely high porosity and is full of lithium ion battery flame retardant and solvent water, which can continuously cool the lithium ion battery and block the propagation of thermal runaway. When the lithium ion battery burns, the lithium ion battery flame retardant can also The anions in the reactants produced by the original thermal runaway can capture the free radicals produced during combustion and prevent the combustion of the battery. The fluorocarbon surfactant used does not contain PFOS, which will not pollute the environment while greatly reducing the surface tension of water. The use of hydrocarbon surfactants and foaming agents can make the fire extinguishing agent produce a large amount of stable foam more quickly, which can quickly cover the surface of the battery, reduce the temperature, and isolate oxygen. The obtained aerogel fire extinguishing agent has a large viscosity. When sprayed on the lithium-ion battery, it can quickly form a "gas-liquid-solid" three-phase insulation layer, adhere to the battery surface, isolate oxygen, and can quickly extinguish the fire while suppressing re-ignition.

[0032] In some embodiments, the inorganic aerogel powder includes at least one of silica aerogel, alumina aerogel, zirconium dioxide aerogel, silicon-aluminum binary aerogel and silicon-zirconium binary aerogel. The above materials are mainly used to utilize extremely high porosity to continuously cool the lithium-ion battery and block the propagation of thermal runaway.

[0033] In some embodiments, the fluorocarbon surfactant includes FS-50, Cap1470, Cap1157 or Cap1440, in order to significantly reduce the surface tension of water without causing pollution to the environment.

[0034] In some embodiments, the hydrocarbon surfactant includes at least one of disodium lauryl sulfosuccinate, disodium fatty alcohol polyoxyethylene ether (3) sulfosuccinate, disodium acid monoethanolamide sulfosuccinate, potassium monododecyl phosphate, alcohol ether phosphate, sodium lauryl amphoacetate, potassium lauryl ether phosphate, and ammonium fatty alcohol polyoxyethylene ether sulfate, mainly to form micelles with the fluorocarbon surfactant to increase the stability of the fire extinguishing agent.

[0035] In some embodiments, the foaming agent includes one of sodium lauryl sulfate, cocamidopropyl betaine, sodium dodecylbenzene sulfonate, lauryl amide propyl betaine, and cocamidopropyl hydroxysulfonate, mainly to enhance the rapid foaming ability of the fire extinguishing agent, so that the fire extinguishing agent can cover the surface of the burning object faster.

[0036] In some embodiments, the lithium ion battery flame retardant includes azobisisobutylimidazoline hydrochloride.

[0037] In some embodiments, the organic solvent includes at least one of diethylene glycol monobutyl ether, ethanol, ethylene glycol, and polyethylene glycol.

[0038] In some embodiments, the antifreeze agent is one or more of methanol, sodium chloride, calcium chloride, magnesium chloride, dimethyl sulfoxide and brine. The use of the above antifreeze agents can ensure the normal use of the fire extinguishing agent at low temperatures and avoid the fire extinguishing agent from freezing and becoming unusable when the ambient temperature is too low.

[0039] The foam stabilizer includes at least one of carbomer, alginate or sodium carboxymethyl cellulose.

[0040] The present invention also provides a method for preparing an aerogel fire extinguishing agent, wherein the preparation of the aerogel fire extinguishing agent comprises the following steps:

[0041] S10, adding a fluorocarbon surfactant, a hydrocarbon surfactant, a foaming agent and an inorganic aerogel powder into water, and stirring evenly to obtain a mixed solution A;

[0042] S20, stirring and dissolving the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and water to obtain a mixed solution B;

[0043] S30, stirring and mixing the mixed solution B and the mixed solution A, and adding the remaining water to obtain an aerogel fire extinguishing agent.

[0044] The method for preparing an aerogel fire extinguishing agent provided by the present invention prepares a mixed solution A and a mixed solution B respectively, thereby preparing an aerogel fire extinguishing agent. The preparation method has simple preparation steps and is easy to promote.

[0045] Further, in step S10, in step S10, the stirring speed is 400-500rpm; and / or, in step S10, the stirring time is 1.5-2h; and / or, in step S20, the stirring speed is 600-700rpm; and / or, in step S20, the stirring time is 0.5h; and / or, in step S30, the stirring speed is 800-1000rpm; and / or, in step S30, the stirring time is 2h. By setting appropriate stirring rate and stirring time, it can be ensured that the material of the aerogel fire extinguishing agent reacts fully with the solution so as to maximize its effectiveness, thereby improving the accuracy of the results and the quality of the aerogel fire extinguishing agent.

[0046] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments and drawings. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0047] Example 1

[0048] An aerogel fire extinguishing agent comprises the following components by mass: 8 parts of inorganic aerogel powder (silicon dioxide aerogel), 4 parts of fluorocarbon surfactant (Cap1470), 5 parts of hydrocarbon surfactant (disodium monoethanolamide sulfosuccinate), 7 parts of foaming agent (sodium dodecyl sulfate), 6 parts of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride), 10 parts of organic solvent (ethanol), 6 parts of antifreeze agent (sodium chloride), 0.08 parts of foam stabilizer (sodium alginate) and 53.92 parts of water, wherein each part is 1g.

[0049] Example 2

[0050] An aerogel fire extinguishing agent, the aerogel fire extinguishing agent comprising the following mass components: 2 parts of inorganic aerogel powder (silicon zirconium binary aerogel), 3 parts of fluorocarbon surfactant (Cap1157), 4 parts of hydrocarbon surfactant (potassium lauryl ether phosphate), 6 parts of foaming agent (cocamidopropyl hydroxysulfobetaine), 4 parts of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride), 8 parts of organic solvent (diethylene glycol monobutyl ether), 1 part of antifreeze agent (methanol), and 0.05 parts of foam stabilizer (sodium carboxymethyl cellulose).

[0051] and 71.95 parts of water, wherein each part is 1 g.

[0052] Example 3

[0053] An aerogel fire extinguishing agent comprises the following components by mass: 10 parts of inorganic aerogel powder (zirconium dioxide aerogel), 5 parts of fluorocarbon surfactant (Cap1440), 6 parts of hydrocarbon surfactant (fatty alcohol polyoxyethylene ether ammonium sulfate), 8 parts of foaming agent (laurylamidopropyl betaine), 10 parts of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride), 13 parts of organic solvent (polyethylene glycol), 10 parts of antifreeze agent (magnesium chloride), 1 part of foam stabilizer (sodium carboxymethyl cellulose) and 37 parts of water, wherein each part is 1g.

[0054] Example 4

[0055] A method for preparing an aerogel fire extinguishing agent comprises the following raw material components by weight: 2.5 g of inorganic aerogel powder (silicon dioxide aerogel, particle size 50-100 μm), 3.5 g of fluorocarbon surfactant (FS-50), 5 g of hydrocarbon surfactant (disodium lauryl sulfosuccinate), 7 g of foaming agent (sodium dodecylbenzene sulfonate), 5 g of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride (AIBI)), 10 g of organic solvent (ethylene glycol), 2 g of antifreeze agent (sodium chloride), 0.5 g of foam stabilizer (sodium carboxymethyl cellulose), and 64.5 g of deionized water.

[0056] Take the components of the high-efficiency aerogel fire extinguishing agent described in Example 4, such as Figure 1 The preparation process shown in the figure comprises the following steps:

[0057] (1) adding a selected amount of fluorocarbon surfactant, hydrocarbon surfactant, foaming agent and inorganic aerogel powder to 25 g of deionized water and stirring for 1.5 h, controlling the speed of the stirrer to 400 rpm, to obtain a mixed solution A;

[0058] (2) Stirring the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and deionized water (not less than 30% of the total amount) for 0.5 h, controlling the speed of the stirrer to 600 rpm, to obtain a mixed solution B;

[0059] (3) Slowly add the mixed solution B into the mixed solution A, and add deionized water to the rated mass fraction, adjust the speed to 900 rpm, and stir for 2 hours to obtain an aerogel fire extinguishing agent.

[0060] Example 5

[0061] The high-efficiency aerogel fire extinguishing agent of this embodiment, calculated on the total amount of raw materials for its preparation, includes the following raw material components by mass: 6g of inorganic aerogel powder (alumina aerogel, particle size 30-50μm), 4g of fluorocarbon surfactant (Cap1470), 5g of hydrocarbon surfactant (potassium monododecyl phosphate), 7g of foaming agent (sodium dodecyl sulfate), 5g of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride (AIBI)), 10g of organic solvent (diethylene glycol monobutyl ether), 2g of antifreeze agent (calcium chloride), 0.1g of foam stabilizer (carbomer), and 60.9g of deionized water.

[0062] The method for preparing the high-efficiency aerogel fire extinguishing agent described in Example 5 comprises the following steps:

[0063] (1) adding a selected amount of fluorocarbon surfactant, hydrocarbon surfactant, foaming agent and inorganic aerogel powder to 25 g of deionized water and stirring for 2 h, controlling the speed of the stirrer to 450 rpm, to obtain a mixed solution A;

[0064] (2) Stirring the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and deionized water (not less than 30% of the total amount) for 0.5 h, controlling the speed of the stirrer to 700 rpm, to obtain a mixed solution B;

[0065] (3) Slowly add the mixed solution B into the mixed solution A, and add deionized water to the rated mass fraction, adjust the speed to 1000 rpm, and stir for 2 hours to obtain an aerogel fire extinguishing agent.

[0066] Example 6

[0067] A method for preparing an aerogel fire extinguishing agent comprises the following steps:

[0068] The high-efficiency aerogel fire extinguishing agent of this embodiment, calculated on the total amount of raw materials used for its preparation, includes the following raw material components by mass: 9g of inorganic aerogel powder (zirconium dioxide aerogel, particle size 15-20 μm), 3g of fluorocarbon surfactant (Cap1157), 6g of hydrocarbon surfactant (alcohol ether phosphate), 6g of foaming agent (laurylamidopropyl betaine), 7g of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride (AIBI)), 8g of organic solvent (diethylene glycol monobutyl ether), 5g of antifreeze agent (calcium chloride), 1g of foam stabilizer (alginate), and 55g of deionized water.

[0069] The method for preparing the high-efficiency aerogel fire extinguishing agent described in Example 6 comprises the following steps:

[0070] (1) adding a selected amount of fluorocarbon surfactant, hydrocarbon surfactant, foaming agent and inorganic aerogel powder to 30 g of deionized water and stirring for 2 h, controlling the speed of the stirrer to 500 rpm, to obtain a mixed solution A;

[0071] (2) Stirring the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and deionized water (not less than 25% of the total amount) for 0.5 h, controlling the speed of the stirrer to 700 rpm, to obtain a mixed solution B;

[0072] (3) Slowly add the mixed solution B into the mixed solution A, and add deionized water to the rated mass fraction, adjust the speed to 1000 rpm, and stir for 2 hours to obtain an aerogel fire extinguishing agent.

[0073] Example 7

[0074] A method for preparing an aerogel fire extinguishing agent comprises the following steps:

[0075] The high-efficiency aerogel fire extinguishing agent of this embodiment, calculated on the total amount of raw materials used for its preparation, includes the following raw material components by mass: 8g of inorganic aerogel powder (silicon zirconium binary aerogel, particle size 15-20 μm), 6g of fluorocarbon surfactant (Cap1440), 8g of hydrocarbon surfactant (sodium lauryl amphoacetate), 8g of foaming agent (sodium dodecylbenzene sulfonate), 5g of lithium ion battery flame retardant (azobisisobutylimidazoline hydrochloride (AIBI)), 8g of organic solvent (ethylene glycol), 1g of antifreeze agent (methanol), 1g of foam stabilizer (alginate), and 55g of deionized water as a balance.

[0076] The method for preparing the high-efficiency aerogel fire extinguishing agent described in this embodiment 7 comprises the following steps:

[0077] (1) adding a selected amount of fluorocarbon surfactant, hydrocarbon surfactant, foaming agent and inorganic aerogel powder to 30 g of deionized water and stirring for 2 h, controlling the speed of the stirrer to 500 rpm, to obtain a mixed solution A;

[0078] (2) Stirring the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and deionized water (not less than 25% of the total amount) for 0.5 h, controlling the speed of the stirrer to 650 rpm, to obtain a mixed solution B;

[0079] (3) Slowly add the mixed solution B into the mixed solution A, and add deionized water to the rated mass fraction, adjust the speed to 900 rpm, and stir for 2 hours to obtain an aerogel fire extinguishing agent.

[0080] Comparative Example 1

[0081] The fire extinguishing agent was prepared according to the method in Example 4, except that no silica aerogel powder was added in Comparative Example 1.

[0082] Comparative Example 2

[0083] The fire extinguishing agent was prepared according to the method in Example 4, except that no lithium ion battery flame retardant was added in Comparative Example 2.

[0084] Comparative Example 3

[0085] Comparative Example 3 used the MSWZ / 6 water-based fire extinguishing agent produced by Beijing Jiujiu Shenlong Fire Fighting Equipment Co., Ltd. to carry out a fire extinguishing experiment.

[0086] Performance Testing

[0087] The aerogel fire extinguishing agents of Examples 4 to 7 and the fire extinguishing agents of Comparative Examples 1 to 3 were subjected to fire extinguishing performance tests, and the results are as follows:

[0088] The fire extinguishing experiment used a battery pack consisting of two 58Ah INP58P square ternary lithium batteries. The first battery was heated by a 350W electric heating plate. When the first battery had thermal runaway, the power of the heating plate was disconnected and the fire extinguishing agent was sprayed at the same time. The fire extinguishing time was the time required for each fire extinguishing agent to extinguish the fire. Whether the fire re-ignites refers to whether the second battery has thermal runaway. If the second battery has thermal runaway, it means that the battery pack has re-ignited. If the second battery does not have thermal runaway, it means that the battery pack has not re-ignited.

[0089] The test results are shown in Table 1:

[0090] Table 1 Fire extinguishing agent performance test results

[0091]

[0092] It can be seen from the data in Table 1 that the fire extinguishing time of Examples 4-7 is all around 30 seconds, and the battery packs do not reignite. The fire extinguishing time of the fire extinguishing agent in Comparative Example 1 without adding silica aerogel powder is 14 seconds longer than that in Example 4. Comparative Example 1 lacks silica aerogel, which can directly affect the thermal runaway propagation, that is, whether the battery pack reignites. Since no silica aerogel is added in Comparative Example 1, the battery pack reignites. This is because the fire extinguishing agent covering the battery surface at this time has only gas-liquid two phases. First, it has greater fluidity and flows away quickly, and cannot stay on the battery surface to continue to absorb heat; second, the high temperature generated during the combustion of the lithium battery can easily destroy the structure of the gas-liquid two-phase foam, and it cannot cover the battery surface well. In the embodiment, due to the addition of silica aerogel, the structure of the foam becomes a solid-liquid-gas three-phase structure. The structure at this time is more stable, and the viscosity is large enough to adhere to the battery surface well. At the same time, silica aerogel is a porous material with a porosity of more than 90%. The pores can absorb more fire extinguishing agents. Such a material attached to the battery surface can continuously cool the battery, thereby extinguishing the fire faster and preventing re-ignition. The fire extinguishing time of the fire extinguishing agent in Comparative Example 2 without adding the lithium ion battery flame retardant is increased by 22s compared with that in Example 4. This is because the lithium ion battery flame retardant can The reactants generated by thermal runaway can be reduced, and the anions therein can capture the free radicals generated by the fuel during the combustion process, thereby inhibiting the combustion of the battery. In Comparative Example 2, in which no lithium-ion battery flame retardant is added, the chain reaction of battery combustion cannot be inhibited, so the fire extinguishing time will be prolonged. At the same time, the second battery in Comparative Example 2 has thermal runaway, which shows that without the addition of lithium-ion battery flame retardant, the fire extinguishing agent loses its good fire suppression effect and cooling effect on the battery; Comparative Example 3 uses a commercially available water-based fire extinguishing agent for fire extinguishing, which can neither inhibit the re-ignition of the battery pack, nor does it have a fire extinguishing time of about 3 times that of the embodiment. The above experiments can show that the fire extinguishing agent prepared by the present invention has a high fire extinguishing efficiency and a better anti-reignition effect.

[0093] The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. For those skilled in the art, the present invention may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the patent protection scope of the present invention.

Claims

1. An aerogel fire extinguishing agent for lithium-ion battery fires, characterized in that: The aerogel fire extinguishing agent comprises the following components by weight: 2-10 parts of inorganic aerogel powder, 3-5 parts of fluorocarbon surfactant, 4-6 parts of hydrocarbon surfactant, 6-8 parts of foaming agent, 4-10 parts of lithium ion battery flame retardant, 8-13 parts of organic solvent, 1-10 parts of antifreeze agent, 0.05-1 parts of foam stabilizer and balance water.

2. The aerogel fire extinguishing agent according to claim 1, characterized in that: The inorganic aerogel powder includes at least one of silicon dioxide aerogel, aluminum oxide aerogel, zirconium dioxide aerogel, silicon-aluminum binary aerogel and silicon-zirconium binary aerogel.

3. The aerogel fire extinguishing agent according to claim 1, characterized in that: The fluorocarbon surfactant includes FS-50, Cap1470, Cap1157 or Cap1440.

4. The aerogel fire extinguishing agent according to claim 1, characterized in that: The hydrocarbon surfactant includes at least one of disodium lauryl sulfosuccinate, disodium fatty alcohol polyoxyethylene ether (3) sulfosuccinate, disodium acid monoethanolamide sulfosuccinate, potassium monododecyl phosphate, alcohol ether phosphate, sodium lauryl amphoacetate, potassium lauryl ether phosphate, and ammonium fatty alcohol polyoxyethylene ether sulfate.

5. The aerogel fire extinguishing agent according to claim 1, characterized in that: The foaming agent includes one of sodium lauryl sulfate, cocamidopropyl betaine, sodium dodecylbenzene sulfonate, lauryl amide propyl betaine, and cocamidopropyl hydroxysulfonate.

6. The aerogel fire extinguishing agent according to claim 1, characterized in that: The lithium ion battery flame retardant includes azobisisobutylimidazoline hydrochloride.

7. The aerogel fire extinguishing agent according to claim 1, characterized in that: The organic solvent includes at least one of diethylene glycol monobutyl ether, ethanol, ethylene glycol, and polyethylene glycol.

8. The aerogel fire extinguishing agent according to claim 1, characterized in that: The antifreeze agent is one or more of methanol, sodium chloride, calcium chloride, magnesium chloride, dimethyl sulfoxide and salt water; and / or, The foam stabilizer includes at least one of carbomer, alginate or sodium carboxymethyl cellulose.

9. A method for preparing an aerogel fire extinguishing agent according to any one of claims 1 to 8, characterized in that: The preparation of the aerogel fire extinguishing agent comprises the following steps: S10, adding a fluorocarbon surfactant, a hydrocarbon surfactant, a foaming agent and an inorganic aerogel powder into water, and stirring evenly to obtain a mixed solution A; S20, stirring and dissolving the lithium ion battery flame retardant, the organic solvent, the foam stabilizer, the antifreeze agent and water to obtain a mixed solution B; S30, stirring and mixing the mixed solution B and the mixed solution A, and adding the remaining water to obtain an aerogel fire extinguishing agent.

10. The method for preparing an aerogel fire extinguishing agent according to claim 9, characterized in that: In step S10, the stirring speed is 400-500 rpm; and / or, In step S10, the stirring time is 1.5-2h; and / or, In step S20, the stirring speed is 600-700 rpm; and / or, In step S20, the stirring time is 0.5h; and / or, In step S30, the stirring speed is 800-1000 rpm; and / or, In step S30, the stirring time is 2 hours.

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