SAFEGUARD AGENT AND USE THEREOF

Abstract

The present disclosure discloses a safeguard agent and a use thereof. The present disclosure provides a safeguard agent consisting of component A and component B, and the molar ratio of the component A to the component B is 1:(1-4). The safeguard agent in the present disclosure can cool the protected space and heat sources, physically isolate heat sources, prevent burning or extinguish the flame in the space, suppress explosion, and effectively and continuously suppress and prevent reignition. Using the safeguard agent of the present disclosure as a suppression agent for battery thermal runaway can achieve the purpose of terminating thermal runaway after cooling, antiflaming, suppression, or extinguishing of a battery in thermal runaway, and more batteries can achieve constant voltage and good appearance without damage phenomena. For other batteries affected by heat in the space, the safeguard agent can also effectively prevent or suppress potential thermal runaway.

Description

TECHNICAL FIELD

The present disclosure relates to a safeguard agent and a use thereof, which are used for the suppression and safety protection of battery thermal runaway.

BACKGROUND

There are two main technologies for preventing burning, i.e., fire retardants and extinguishants, wherein the former renders burning impossible or difficult to occur, and the latter releases agents to extinguish the flame when the burning occurs. Fire retardants are added to combustibles, such as treating fabrics, wood, plastics, and rubber, so that combustibles cannot burn, or cannot burn constantly at high temperatures. Or, fire-retardant glue or fire-retardant board is used to physically isolate the burning material, making it difficult for the flame to spread and the burning to continue. The extinguishant is stored in an independent container. Once a fire starts, it is artificially or automatically sprayed to the object or the room on fire to extinguish the flame and the burning.

Fire retardants are usually added to combustibles as additives. However, for some high-risk commodities such as lithium batteries, even with the addition of fire retardants, thermal runaway and burning still occur inevitably, and explosions also occur from time to time. In addition, adding a large amount of fire retardants to the battery will affect the electrochemical performance of the battery, and the economic efficiency is poor.

Liquid water and foam, chemical gases and solid dry powder are generally used as extinguishants, and local application and total flooding are used to extinguish the fire. Local application refers to spraying an extinguishant on the protective object for a long time, without the need for space limitation, such as extinguishing with an extinguisher and spraying pressure water mist on fire. Total flooding refers to gaseous extinguishants, such as heptafluoropropane FM-200, perfluorohexanone Novec-1230, inert gas IG-541, which require a well-sealed protected space. It is necessary to test the enclosure integrity and leakage of the protected space according to relevant standards and procedures, so that a certain volume percentage and a certain duration of chemical concentration can be maintained in the space in order to extinguish the flame and constantly suppress the burning.

For small or micro spaces, such as battery cabinets or battery packages, conventional technology of chemical gaseous extinguishants cannot effectively deal with the situation which the enclosure integrity is damaged, and the agent will leak or diffuse quickly and the purpose of fire extinguishing cannot be achieved. The thermal runaway of a battery is caused by internal short circuit brought by internal factors such as battery manufacturing defects or lithium dendrite phenomenon, or external factors such as impact, heating, external short circuit or wiring process. After the thermal runaway of the battery, an irreversible energy release is formed, manifested as constant heat generation, generation of inflammable and explosive gas, violent deflagration or explosion, continuous burning, smoke generation, or flameless combustion. Most of these phenomena appear in combination. Thermal runaway is not equal to burning, and burning is only one of the accompanying phenomena. Thermal runaway without burning, only with heat and gas generation, is also more common. Thermal runaway sometimes manifests itself as flameless combustion, such as the ternary pouch battery added with fire retardants. Flameless combustion is live coal-like glow and smoke, which is a typical characteristic of deep-seated fire.

It'd been confirmed by a large number of experiments and research reports that conventional technologies of fire retardants and extinguishants, commonly used extinguishants such as perfluorohexanone, heptafluoropropane, hexafluoropropane, aerosol, high-pressure water mist, low-expansion foam and high-expansion foam, all cannot effectively deal with thermal runaway and burning of lithium battery in a small amount. After the fire is extinguished in battery thermal runaway, it is normal for the battery to resume burning because the interior of the battery constantly generates flammable gas and heat. For application of fire fighting such as water and foam, a large amount of agents form water damages, which results in secondary losses and total battery loss. Studies and tests on heptafluoropropane and Novec-1230, etc. have shown that only surface flame can be extinguished, and even if the used amount of the agents is huge, the thermal runaway of battery still cannot be terminated. 3M, the manufacturer of Novec-1230, had stated in a written declaration in August 2017 that clean agents are ineffective in avoiding and preventing thermal runaway, as are foams and dry powders.

It has been known to the public that lithium batteries are prone to thermal runaway and reignition frequently, for which the existing flame-retardant and fire-fighting technologies are powerless. The strong market demand urgently requires new forms of products to solve the above safety problems, and creative solutions and technical routes are required.

BRIEF SUMMARY OF THE INVENTION

Therefore, the technical problem solved by the present disclosure is a problem that if a large number of batteries are in an enclosure, or a space where the enclosure integrity is damaged or a space with poor sealing space, the batteries are prone to thermal runaway which cannot be terminated, and the batteries catch fire after the thermal propagation, and reignition after being extinguished by fire-fighting technology. The present disclosure provides a safeguard agent and a use thereof. The safeguard agent of the present disclosure can continuously cool, physically isolate and chemically suppress the burning to prevent the formation of the burning conditions, terminate the chemical reaction or suppress the unfavorable chain reaction, and finally heat and flammable and explosive gases are no longer produced, and completely terminate thermal runaway of a battery when the thermal runaway of the battery generates a large amount of heat and gas.

Specifically, when the signs of thermal runaway appear, the safeguard agent of the present disclosure can be released at the same time or after a delay, and it can remain for a long time even in a space with poor sealing, and continue to play the role of cooling, isolation and suppression, preventing burning or suppressing explosions. Even if the burning occurs before release, it can extinguish the flame immediately and suppress it for a long time to prevent reignition. As a result, the following logical evolution is fundamentally blocked: When the thermal runaway of the battery cannot be terminated, thermal propagation occurs between the batteries, and the battery is thermally runaway again, further igniting and burning.

The present disclosure provides a safeguard agent, consisting of component A and component B; the component A is selected from one or more of a C₅-C₈ perfluoroalkane, a C₅-C₇ perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C₅-C₈ fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms (the C₅-C₈ fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms consists of three elements fluorine, carbon and hydrogen), a C₄-C₇ perfluoroketone, a C₄-C₇ fluoroether, a C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups and heptafluoro-2-(1,2,2-trifluoroethyleneoxy)propane; the C₄-C₇ fluoroether contains at least 7 fluorine atoms;

• • the component B is a C₃-C₅ bromofluoroalkene and/or a C₂-C₄ iodofluoroalkane; the bromofluoroalkene contains at least 2 fluorine atoms; the C₂-C₄ iodofluoroalkane contains at least 4 fluorine atoms;
  • the molar ratio of the component A to the component B is 1:(1-4).

In a certain embodiment, the safeguard agent is a cooling suppressant or an extinguishant.

In a certain embodiment, the safeguard agent can be used in a walled space, a sealed space or an enclosure, such as the walled space or the enclosure.

In a certain embodiment, the safeguard agent is used to protect a battery or suppress energy that is continuously released from the battery during thermal runaway.

In a certain embodiment, the battery is preferably a battery that releases energy in seconds when thermal runaway occurs, preferably a lithium-ion battery that releases energy in seconds.

In a certain embodiment, the lithium-ion battery is a ternary lithium battery, a lithium-cobalt battery or a lithium manganese battery.

In a certain embodiment, the lithium-ion battery is a prismatic battery, a pouch battery or a cylinder battery.

In a certain embodiment, the release mode of energy release during thermal runaway is violent heat generation, gas generation, burning or explosion; the thermal runaway is caused by internal short circuit or external short circuit of the battery, which can be simulatively induced through nail penetration or heating experiment.

In a certain embodiment, the safeguard agent is a homogeneous liquid (wherein the meaning of homogeneous liquid is that the components of the safeguard agent are homogeneously distributed without stratification).

In a certain embodiment, the safeguard agent can be used to suppress heat generation, gas generation or burning caused by thermal runaway of a battery.

In one embodiment, the molar ratio of the component A to the component B is 1:(2-4), such as 1:3.

In a certain embodiment, the C₂-C₄ iodofluoroalkane contains one iodine atom.

In a certain embodiment, the C₃-C₅ bromofluoroalkene contains one bromine atom.

In a certain embodiment, the C₅-C₈ perfluoroalkane can be selected from perfluorohexane and/or perfluoroheptane, and the perfluorohexane is preferably perfluoro-n-hexane, perfluoro-2-methylpentane or perfluoro-2,3-dimethylbutane; the perfluoroheptane is preferably perfluoro-n-heptane. The C₅-C₈ perfluoroalkane is, for example, selected from one or more of

In a certain embodiment, the C₅-C₈ fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms can be decafluoropentane and/or monohydrotridecafluorohexane, such as

In a certain embodiment, the C₅-C₇ perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups can be dodecafluorocyclohexane and/or perfluoromethylcyclopentane.

In a certain embodiment, the C₄-C₇ perfluoroketone contains 1 or 2 carbonyl groups.

In a certain embodiment, the C₄-C₇ perfluoroketone is 1,1,1,3,4,4,4-heptafluoro-3-(trifluoromethyl)butan-2-one and/or perfluoro-2-methyl-3-pentanone.

In a certain embodiment, the C₄-C₇ fluoroether contains 1 or 2 oxygen atoms.

In a certain embodiment, the C₄-C₇ fluoroether can be selected from one or more of 2-(difluoro(methoxy)methyl)-1,1,1,2,3,3,3-heptafluoropropane, 2,2,3,3,3-pentafluoropropyl difluoromethyl ether, methylnonafluorobutylether, heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether, 1,1,1,2,2,3,3-heptafluoro-3-methoxypropane, 2-(difluoromethoxymethyl)-1,1,1,2,3,3,3-heptafluoropropane and 1-ethoxy-1,1,2,3,3,3-hexafluoro-2-(trifluoromethyl)propane; for example, selected from one or more of

In a certain embodiment, the C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups contains 1 oxygen atom.

In a certain embodiment, the C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups, wherein the C₂-C₆ refers to the carbon atoms on the ring.

In a certain embodiment, the C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups can be perfluorocycloheptyl ether or perfluoro-2-methyl-2,3-epoxypentane.

In a certain embodiment, the C₃-C₅ bromofluoroalkene can be selected from one or more of 3-bromo-3,3-difluoropropene, 2-bromo-3,3,3-trifluoropropene, 3-bromo-1,1,3,3-tetrafluoropropene, 2-bromo-3,3,4,4,4-pentafluoro-1-butene, 2-bromo-3,4,4,4-tetrafluoro-3-(trifluoromethyl)but-1-ene and 2-bromo-3,3,4,4,5,5,5-octafluoro-1-pentene, for example, selected from one or more of

In a certain embodiment, the C₂-C₄ iodofluoroalkane can be selected from one or more of 1,1,1,2-tetrafluoro-2-iodoethane, iodo-1,1,2,2-tetrafluoroethane and iodoperfluorobutane, the iodoperfluorobutane is preferably 1-iodoperfluorobutane and/or 2-iodononafluorobutane, for example, selected from one or more of

In a certain embodiment, the component A is selected from one or two of a C₅-C₇ perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C₄-C₇ perfluoroketone, C₂-C₄ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups and a C₄-C₇ fluoroether, the C₄-C₇ fluoroether contains at least 7 fluorine atoms.

In a certain embodiment, the component A is selected from one or more of

In a certain embodiment, the component A is selected from one or two of

In a certain embodiment, the component B is preferably selected from a C₃ bromofluoroalkene and/or a C₄ iodoperfluoroalkane; for example, selected from one or more of

In a certain embodiment, the component B is more preferably selected from

In a certain embodiment, the boiling point of the component A can be 20-85° C., preferably 25-60° C., such as 48° C., 55° C., 49.2° C., 49.5° C., 60° C. or 72° C.

In a certain embodiment, the boiling point of the component B can be 30-80° C., preferably 30-67° C., such as 34° C. or 64-67° C.

In a certain embodiment, the molecular weight of the component A can be 200-400 g/mol, preferably 250-370 g/mol, such as 250 g/mol, 252 g/mol, 366 g/mol, 264 g/mol, 300 g/mol or 316 g/mol.

In a certain embodiment, the molecular weight of the component B can be 150-400 g/mol, preferably 170-350 g/mol, such as 175 g/mol or 346 g/mol.

In a certain embodiment, the latent heat of vaporization of the component A can be 21.6-34.4 kJ/mol, preferably 26-32 kJ/mol, such as 27.3 kJ/mol, 27.8 kJ/mol, 27.9 kJ/mol, 28.3 kJ/mol, 30.7 kJ/mol or 31.5 kJ/mol.

In a certain embodiment, the latent heat of vaporization of the component B can be 24.2-33.2 kJ/mol, preferably 28-33 kJ/mol, such as 30.6 kJ/mol or 29.6 kJ/mol.

In a certain embodiment, the safeguard agent adopts scheme 1, scheme 2, scheme 3, scheme 4, scheme 5, scheme 6, scheme 7 or scheme 8

			Molar ratio of
			component A to
	Component A	Component B	component B
Scheme 1			1:3
Scheme 2			1:2
Scheme 3			2:5
Scheme 4			1:3
Scheme 5			1:2
Scheme 6			1:4
Scheme 7			1:1
Scheme 8			1:2

The present disclosure also provides a safeguard agent, consisting of component A and component B; and the latent heat of vaporization of the component A is 21.6-34.4 kJ/mol; the latent heat of vaporization of the component B is 24.2-33.2 kJ/mol; the boiling point of the component A is 20-85° C.; the boiling point of the component B is 30-80° C.; the number of fluorine atoms of the compound in the component A is 7-16, and the number of carbon atoms of the compound in the component A is 4-7; the compound in the component B contains at least one bromine or iodine atom; the number of hydrogen atoms of the compound in the component A is 0-5; the molecular weight of the component A is 200-400 g/mol; the molecular weight of the component B is 150-400 g/mol;

• • the molar ratio of the component A to the component B is 1:(1-4).

In a certain embodiment, the molar ratio of the component A to the component B is 1:(2-4), such as 1:3.

In a certain embodiment, the component A is selected from one or more of a C₅-C₈ perfluoroalkane, a C₅-C₇ perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C₅-C₈ fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms (the C₅-C₈ fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms consists of three elements fluorine, carbon and hydrogen), a C₄-C₇ perfluoroketone, a C₄-C₇ fluoroether, a C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups and heptafluoro-2-(1,2,2-trifluoroethyleneoxy)propane; the C₄-C₇ fluoroether contains at least 7 fluorine atoms.

In a certain embodiment, the component B is a C₃-C₅ bromofluoroalkene and/or a C₂-C₄ iodofluoroalkane; the bromofluoroalkene contains at least 2 fluorine atoms; the C₂-C₄ iodofluoroalkane contains at least 4 fluorine atoms.

In one embodiment, the safeguard agent is a homogeneous liquid (wherein the meaning of homogeneous liquid is that the components of the safeguard agent are homogeneously distributed without stratification).

In a certain embodiment, the safeguard agent is a cooling suppressant or an extinguishant.

In one embodiment, the safeguard agent can be used in a walled space, a sealed space or an enclosure.

In a certain embodiment, the safeguard agent is used to protect a battery or suppress energy that is continuously released from the battery during thermal runaway.

In a certain embodiment, the battery is preferably a battery that releases energy in seconds when thermal runaway occurs, preferably a lithium-ion battery that releases energy in seconds.

In one embodiment, the lithium-ion battery is a ternary lithium battery, a lithium-cobalt battery or a lithium manganese battery.

In a certain embodiment, the lithium-ion battery is a prismatic battery, a pouch battery or a cylinder battery.

In a certain embodiment, the release mode of energy release during thermal runaway is violent heat generation, gas generation, burning or explosion; the thermal runaway can be caused by internal short circuit or external short circuit of the battery, which can be simulatively induced through nail penetration or heating experiment.

In a certain embodiment, the safeguard agent can be used to suppress heat generation, gas generation or burning caused by thermal runaway of a battery.

In a certain embodiment, the number of the release of the safeguard agent can be one or more times in the use.

In a certain embodiment, the more times are preferably three times in the use.

In a certain embodiment, the C₂-C₄ iodofluoroalkane contains one iodine atom.

In a certain embodiment, the C₃-C₅ bromofluoroalkene contains one bromine atom.

In a certain embodiment, the C₅-C₈ perfluoroalkane can be selected from perfluorohexane and/or perfluoroheptane, and the perfluorohexane is preferably perfluoro-n-hexane, perfluoro-2-methylpentane or perfluoro-2,3-dimethylbutane; the perfluoroheptane is preferably perfluoro-n-heptane. The C₅-C₈ perfluoroalkane is, for example, selected from one or more of

In a certain embodiment, the C₅-C₈ fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms can be decafluoropentane and/or monohydrotridecafluorohexane, such as

In a certain embodiment, the C₅-C₇ perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups can be dodecafluorocyclohexane and/or perfluoromethylcyclopentane.

In a certain embodiment, the C₄-C₇ perfluoroketone contains 1 or 2 carbonyl groups.

In a certain embodiment, the C₄-C₇ perfluoroketone is 1,1,1,3,4,4,4-heptafluoro-3-(trifluoromethyl)butan-2-one and/or perfluoro-2-methyl-3-pentanone.

In a certain embodiment, the C₄-C₇ fluoroether contains 1 or 2 oxygen atoms.

In a certain embodiment, the C₄-C₇ fluoroether can be selected from one or more of 2-(difluoro(methoxy)methyl)-1,1,1,2,3,3,3-heptafluoropropane, 2,2,3,3,3-pentafluoropropyl difluoromethyl ether, methylnonafluorobutylether, heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether, 1,1,1,2,2,3,3-heptafluoro-3-methoxypropane, 2-(difluoromethoxymethyl)-1,1,1,2,3,3,3-heptafluoropropane and 1-ethoxy-1,1,2,3,3,3-hexafluoro-2-(trifluoromethyl)propane; for example, selected from one or more of

In a certain embodiment, the C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups contains one oxygen atom.

In a certain embodiment, the C₂-C₆ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups can be perfluorocycloheptyl ether or 2-methyl-2,3-epoxypentane.

In a certain embodiment, the C₃-C₅ bromofluoroalkene can be selected from one or more of 3-bromo-3,3-difluoropropene, 2-bromo-3,3,3-trifluoropropene, 3-bromo-1,1,3,3-tetrafluoropropene, 2-bromo-3,3,4,4,4-pentafluoro-1-butene, 2-bromo-3,4,4,4-tetrafluoro-3-(trifluoromethyl)but-1-ene and 2-bromo-3,3,4,4,5,5,5-octafluoro-1-pentene, for example, selected from one or more of

In a certain embodiment, the C₂-C₄ iodofluoroalkane can be selected from one or more of 1,1,1,2-tetrafluoro-2-iodoethane, iodo-1,1,2,2-tetrafluoroethane and iodoperfluorobutane, the iodoperfluorobutane is preferably 1-iodoperfluorobutane and/or 2-iodononafluorobutane, for example, selected from one or more of

In a certain embodiment, the component A is selected from one or two of a C₅-C₇ perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C₄-C₇ perfluoroketone, a C₂-C₄ perfluorocyclic ether which is unsubstituted or substituted by one or more C₁-C₃ perfluoroalkyl groups and a C₄-C₇ fluoroether, the C₄-C₇ fluoroether contains at least 7 fluorine atoms.

In a certain embodiment, the component A is selected from one or more of

In a certain embodiment, the component A is selected from one or two of

In a certain embodiment, the component B is preferably selected from a C₃ bromofluoroalkene and/or a C₄ iodoperfluoroalkane; for example, selected from one or more of

In a certain embodiment, the component B is more preferably selected from

In a certain embodiment, the boiling point of the component A is preferably 25-75° C., such as 48° C., 49.2° C., 49.5° C., 55° C., 60° C. or 72° C.

In a certain embodiment, the boiling point of the component B is preferably 30-67° C., such as 34° C. or 64-67° C.

In a certain embodiment, the molecular weight of the component A is preferably 250-370 g/mol, such as 250 g/mol, 252 g/mol, 366 g/mol, 264 g/mol, 300 g/mol or 316 g/mol.

In a certain embodiment, the molecular weight of the component B is preferably 170-350 g/mol, such as 175 g/mol or 346 g/mol.

In a certain embodiment, the latent heat of vaporization of the component A is preferably 26-32 kJ/mol, such as 27.3 kJ/mol, 27.8 kJ/mol, 27.9 kJ/mol, 28.3 kJ/mol, 30.7 kJ/mol or 31.5 kJ/mol.

In a certain embodiment, the latent heat of vaporization of the component B is preferably 28-33 kJ/mol, such as 30.6 kJ/mol or 29.6 kJ/mol.

In a certain embodiment, the safeguard agent adopts scheme 1, scheme 2, scheme 3, scheme 4, scheme 5, scheme 6, scheme 7 or scheme 8

			Molar ratio of
			component A to
	Component A	Component B	component B
Scheme 1			1:3
Scheme 2			1:2
Scheme 3			2:5
Scheme 4			1:3
Scheme 5			1:2
Scheme 6			1:4
Scheme 7			1:1
Scheme 8

The present disclosure also provides a thermal runaway suppressant or a fire suppressant comprising a mixture of the above-mentioned safeguard agent and one or more extinguishants.

The present disclosure also provides an extinguishing equipment comprising the above-mentioned safeguard agent or the above-mentioned thermal runaway suppressant or the fire suppressant.

The present disclosure also provides a battery system comprising the above-mentioned safeguard agent or the above-mentioned thermal runaway suppressant or the fire suppressant, wherein the safeguard agent or the thermal runaway suppressant or fire suppressant is used to suppress or terminate thermal runaway of the battery system.

The present disclosure also provides a safeguard agent system comprising one or more safeguard agent containers;

• • when the safeguard agent system comprises a plurality of the containers, each container independently contains the above-mentioned component A and/or the above-mentioned component B, respectively stored in the containers; the molar ratio of the component A to the component B in the containers is 1:(1-4);
  • when the safeguard agent system comprises one container, the above-mentioned component A and the component B are stored in the container at a molar ratio of 1:(1-4).

In a certain embodiment, the safeguard agent system plays the role of cooling, isolation, antiflaming, explosion suppression or extinguishing by releasing the safeguard agent. When the safeguard agent system comprises two or more containers, the agents in the two or more containers can be released simultaneously or sequentially, if satisfied, the molar ratio of component A to component B in the released agents is 1:(1-4), preferably 1:(2-4), such as 1:3. The present disclosure also provides a method for controlling thermal runaway comprising the following steps: releasing or releasing in advance the above-mentioned safeguard agent to an object that has appeared thermal runaway or an object that is about to appear thermal runaway;

alternatively, releasing or releasing in advance the above-mentioned component A and the component B respectively to the object that has appeared thermal runaway or the object that is about to appear thermal runaway.

The molar rate ratio of the release of the component A to the component B is 1:(1-4), preferably 1:(2-4), such as 1:3.

In the method, the method can be used in a walled space, a sealed space or an enclosure, such as the walled space or the enclosure.

In the method, the number of the release of the safeguard agent can be one or more times.

In the method, the more times are preferably three times.

In the method, the method is used for the object that has appeared thermal runaway or the object that is about to appear thermal runaway, and the object that has appeared thermal runaway or the object that is about to appear thermal runaway is a battery that release energy in seconds or combustibles that have characteristics of deep-seated fire such as wood, paper, cotton, and grain.

The battery is preferably a battery that releases energy in seconds when thermal runaway occurs, preferably a lithium-ion battery that releases energy in seconds.

The lithium-ion battery is a ternary lithium battery, a lithium-cobalt battery or a lithium manganese battery.

The lithium-ion battery is a prismatic battery, a pouch battery or a cylinder battery.

The release mode of energy release is violent heat generation, gas generation or burning; the thermal runaway is mostly caused by internal short circuit or external short circuit of the battery and the like, which can be simulatively induced through nail penetration or heating experiment.

DEFINITION OF TERMS

The substituted perfluorinated compound in the present disclosure is that the fluorine atoms in the compound are substituted by other groups, for example, the C₂-C₆ perfluorocyclic ether substituted by one or more C₁-C₃ perfluoroalkyl groups is that the fluorine atoms on the C₂-C₆ perfluorocyclic ether are substituted by one or more C₁-C₃ perfluoroalkyl groups.

In the present disclosure, the term “more” is 2, 3, 4 or more.

In the present disclosure, energy release in seconds refers to a state of violent energy release when thermal runaway occurs, and the duration is within 10 seconds, 30 seconds or 60 seconds, and the releasing duration is within about 100 seconds when the cell energy is large.

In the present disclosure, a sealed space refers to a tightly closed and well-sealed space to prevent water vapor from entering or steam from evaporating. Its subordinate concepts include high IP level electrical cabinets and boxes, such as IP67 or IP68.

In the present disclosure, an enclosure refers to a closed but not sealed space to prevent dust or foreign objects from entering. Its subordinate concepts include fire gas protected closed spaces with less leakage and able to maintain gas fire extinguishing concentration; and low IP level electrical cabinets, such as indoor IP34, IP44 or outdoor IP54, IP56.

In the present disclosure, an walled space refers to a space enclosed on all sides, such as a space with no leakage on all sides, such as a space with no leakage on all sides and bottom.

The above preferred conditions can be combined arbitrarily to obtain preferred embodiments of the present disclosure without violating common knowledge in the art.

The reagents and raw materials used in the present disclosure are all commercially available.

The positive progressive effect of the present disclosure is that the safeguard agent comprised in the present disclosure can cool the protected space and heat sources, physically isolate heat sources, prevent burning or extinguish the flame in the space, suppress explosion, and effectively and continuously suppress and prevent reignition. Using the safeguard agent of the present disclosure as a suppression agent for battery thermal runaway can achieve the purpose of terminating the thermal runaway after cooling, antiflaming, suppression, or extinguishing of a battery in thermal runaway, and more batteries can achieve constant voltage and good appearance without damage phenomena. For other batteries affected by heat in the space, the safeguard agent can also effectively prevent or suppress potential thermal runaway.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure will be further described below with reference to examples, but the present disclosure is not therefore limited to the scope of the examples. Experimental methods without specific conditions in the following examples are selected according to conventional methods and conditions, or according to the commercial specification.

The test scenes in the detailed description of the preferred embodiment are shown in the following table

			Trigger	Steady-
NO.	Test box	Battery type	method	state time
Scene 1	1200 L cabinet	21700 module 3 × 3	Nail	Vigorous
	without top	cell 4.8 Ah 100% SOC (State	penetration	release 33 s
		of Charge)(21700 refers to a
		cylinder battery with a
		diameter of 21 mm and a
		length of 70 mm)
Scene 2	500 L enclosure	Ternary prismatic battery	Nail	Vigorous
	box	40 Ah	penetration	release 13 s
		A 100% SOC cell (prismatic
		refers to a battery is a hard
		shell cuboid)
Scene 3	150 L airtight	Ternary pouch battery 58 Ah	Electric	Vigorous
	box	A 100% SOC cell (pouch	heating	release 10 s
		refers to a battery is a pouch-
		shaped thin cuboid)
Note:
1. A cabinet without top means that the top is completely open, the surrounding and bottom are steel plates, and there is no leakage around, simulating the environment of a battery warehouse or a battery cabinet with an open top, which is one of the walled spaces.

Enclosure box refers to a sealed but not airtight, less leakage, about IP44, simulating energy storage battery cabinet.

Airtight box simulates the airtight environment of the vehicle battery package, and has good airtightness, very little leakage, about IP67 or more.

Both airtight and enclosure test box are equipped with safety measures which are discontinuous relief device.

2. The violent release of thermal runaway of the battery cell refers to the violent release duration of the stored power of the battery cell. The violent release refers to the generation of high-speed off-gas, deflagration, and continuous mass fire. Small smoke and small fire are not violent.

3. The trigger method refers to the method of causing thermal runaway of the battery cell. Generally, nail penetration or electric heating is used to simulate the thermal runaway caused by an internal short circuit, so that the battery energy is released in seconds.

4. 100% SOC means that the battery is fully charged, and the Ah number is the battery capacity, indicating the power that can be stored.

IP is the level of protection against ingress of foreign objects by the casing of electrical equipment, as defined in the standard GB 4208-2008/IEC 60529-2001 “Degrees of Protection Provided by Enclosure (IP Code)”.

The burning situation of each test scene in the detailed description of the preferred embodiment when not adding safeguard agent is shown in the following table;

		Thermal	Steady-
	Description of thermal runaway	runaway	state
NO.	phenomenon	duration	duration	Battery test
Scene 1	A cell is penetrated by a nail;	Deflagration	Vigorously	The voltage
	thermal runaway and deflagration	and burning	lasts 33 s	of these 9
	occur, and the flame gradually	last for 1 min		pcs cells are
	extinguishes; after 5 minutes	16 s		0
	without flame and with smoke, the
	rest of the battery cells are
	discontinuously thermal runaway
	and deflagrated, and continued to jet
	fire.
Scene 2	A large amount of gas and sparks are	Off-gas	Vigorously	The voltage
	generated, and an explosion occurs	jetting,	lasts for 13 s	is 0, the
	instantly, blowing up the test box	deflagration		casing is
	and smashing the observation	and burning		cracked and
	window. Deflagrates violently, jets	last for 28 s		lifted
	fire and burns for a while.
Scene 3	The cell punch ruptures and catches	Burning and	Vigorously	The voltage
	fire. The fire continues to be jets,	deflagration	lasts for 10 s	is 0, and
	and the pressure relief plate bounces	last for 15 s,		there are
	with time intervals. After there is no	and live coal-		many splits
	open flame, a large amount of	like flameless		around
	smoke is still produced.	burning lasts
		for a long
		time

Each component name and structure in the detailed description of the preferred embodiment are shown in the following table:

		Latent heat of
Component		vaporization	Boiling point	Molecular
name	Structure	KJ/mol	° C.	weight g/mol
A1		27.3 KJ/mol	49.5	264
A2		27.9 KJ/mol	48	300
A3		27.8 KJ/mol	49.2	316
A4		28.3 KJ/mol	60	250
A5		30.7 KJ/mol	55	252
A6		31.5 KJ/mol	72	366
B1		30.6 KJ/mol	34	175
B2		29.6 KJ/mol	64-67	346

The component A and the component B were mixed homogeneously according to a certain volume ratio. Where, the types and proportions of the component A and component B are specifically shown in the following table:

			Molar ratio of
Example			component A to
number	Component A	Component B	component B
Example 1	A1	B1	A1:B1 = 1:3
Example 2	A1	B2	A1:B2 = 1:2
Example 3	A2 + A3	B1	A2:A3:B1 = 1:1:5
Example 4	A3	B1	A3:B1 = 1:3
Example 5	A3	B1	A3:B1 = 1:2
Example 6	A4	B1	A4:B1 = 1:4
Example 7	A5	B2	A5:B2 = 1:1
Example 8	A5 + A6	B2	A5:A6:B1 = 1:1:4

Mixing Method of Agent

Component A and component B were mixed and stirred evenly to obtain the safeguard agent.

Releasing Method of Agent

The safeguard agent was stored in a container, pressurized by the gas, and when released, the pressure pushed the safeguard agent to release through a pipeline and a nozzle.

At this time, the gas could be an inert gas such as N₂ or Ar₂.

The safeguard agent could be sucked or pushed out by a method of a pump or a piston, and released through a pipeline and a nozzle.

Effect Example 1: The effect data of the safeguard agent in Example 1 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	The agent is released totally, and	1300	It is observed that	The voltage of
	then a cell is penetrated. It can be		the unburned	one cell is 0 V,
	seen that sparks are ejected, but no		duration is 10	the voltage of
	flame is seen. It can be seen that		minutes, and the	the adjacent one
	the casing of the penetrated cell		burning torch in	is 2.6 V, and the
	turns red, and no burning is seen		the test is still	remaining 7 pcs
	until the end.		extinguished	are available at
				4.2 V.
Scene 2	The agent is sprayed once in	2100	It is observed that	The voltage is 0
	advance, then the cell is		the unburned	V, the cell film
	penetrated, and then the agent is		duration is 90	isn't melted; and
	released automatically with time		minutes, and the	the bottom film
	intervals. The cell generates a		burning torch is	is relatively
	large amount of off-gas with		extinguished in	intact
	violent disturbance, and gas		three tests
	overflows from the gap in the box,
	sparks can be seen, and no
	burning is seen until the end.
Scene 3	The film punch ruptures and jets	900	It is observed that	The voltage is 0
	fire, and the agent is released		the unburned	V, and the
	automatically with time intervals		duration is 90 min,	battery is
	for multiple times. It can be seen		and the burning	seriously
	that the flame lasts for about 2		torch is	cracked with
	seconds. After the fire is		extinguished in	obvious splits.
	extinguished, there is still a high-		three tests
	speed off-gas. It can be seen that
	the interior is like live coal, and
	the pressure relief plate bounces
	with time intervals. The
	disturbance in the box gradually
	calms down, and and no burning
	is seen until the end.

Effect Example 2: The effect data of the safeguard agent in Example 2 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	The agent is sprayed once in	2100	It is observed that	The voltage of
	advance, then the cell is		the unburned	one cell is 0 V,
	penetrated. It can be seen that		duration is 15	the voltage of
	sparks are ejected, but no flame		minutes, and the	the adjacent one
	is seen. It can be seen that the		burning torch in	is 1.4 V, and the
	casing of the penetrated cell turns		the test is still	remaining 7 pcs
	red, and no burning is seen until		extinguished	are available at
	the end.			4.2 V.
Scene 2	When the cell is penetrated, the	3400	It is observed that	The voltage is 0
	agent is released automatically		the unburned	V, the cell film
	with time intervals for multiple		duration is 110	isn't melted; and
	times. The cell generates a large		minutes, and the	the bottom film
	amount of off-gas with violent		burning torch is	is relatively
	disturbance, and gas overflows		extinguished in	intact
	from the gap in the box, sparks		three tests
	can be seen, and no burning is
	seen until the end.
Scene 3	The film punch ruptures and jets	1500	It is observed that	The voltage is 0
	fire, and the agent is released		the unburned	V, the battery
	totally. It can be seen that the		duration is 110	has obvious
	flame lasts for about 1 second.		min, and the	splits.
	After the fire is extinguished,		burning torch is
	there is still a high-speed off-gas.		extinguished in
	It can be seen that the interior is		three tests
	like live coal, and the pressure
	relief plate bounces in the early
	stage. The disturbance in the box
	gradually calms down, and no
	burning is seen until the end.

Effect Example 3: The effect data of the safeguard agent in Example 3 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	The agent is released totally,	1400	It is observed that	The voltage of one
	and then a cell is penetrated. It		the unburned	cell is 0 V, the
	can be seen that sparks are		duration is 10	voltage of the
	ejected, but no flame is seen. It		minutes, and the	adjacent one is 1.8
	can be seen that the casing of		burning torch in	V, and the
	the penetrated cell turns red,		the test is still	remaining 7 pcs are
	and no burning is seen until the		extinguished	available at 4.2 V.
	end.
Scene 2	The agent is sprayed once in	2250	It is observed that	The voltage is 0 V,
	advance, then the cell is		the unburned	the shape does not
	penetrated, and then the agent is		duration is 90	change
	released automatically with		min, and the	significantly, and
	time intervals. The cell		burning torch is	the bottom cell
	generates a large amount of off-		extinguished in	film is not melted
	gas with violent disturbance,		three tests
	and a small amount of gas
	overflows from the gap in the
	box, a few sparks can be seen,
	and no flame is seen until the
	end.
Scene 3	The cell punch ruptures and	1000	It is observed that	The voltage is 0 V,
	burns, and the agent is released		the unburned	and the battery is
	automatically with time		duration is 90	seriously cracked
	intervals for multiple times. It		min, and the	with obvious
	can be seen that the flame lasts		burning torch is	splits.
	for about 3 seconds, and a high-		extinguished in
	speed off-gas is generated. It		three tests
	can be seen that the interior is
	like live coal, and no flame is
	seen. The pressure relief plate
	bounces with time intervals.
	The disturbance in the box
	gradually calms down.

Effect Example 4: The effect data of the safeguard agent in Example 4 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	A cell is penetrated, and the	1400	It is observed that	The voltage of one
	agent is released at the same		the unburned	cell is 0 V, the
	time, which is sprayed		duration is 10	voltage of the
	multiple times. It can be seen		minutes, and the	adjacent one is 0.18
	that sparks are ejected, but no		burning torch in	V, the voltage of the
	flame is seen. The casing of		the test is still	other adjacent one is
	the penetrated cell turns red,		extinguished	0.26 V, and the
	and no burning is seen until			remaining 6 pcs are
	the end.			available at 4.2 V.
Scene 2	When the cell is penetrated,	2200	It is observed that	The voltage is 0 V,
	the agent is released		the unburned	the shape does not
	automatically with time		duration is 90	change significantly,
	intervals for multiple times.		minutes, and the	and the bottom cell
	The cell generates a large		burning torch is	film is not melted
	amount of off-gas with violent		extinguished in
	disturbance, and a small		three tests
	amount of gas overflows from
	the gap in the box, a few
	sparks can be seen, and no
	burning is seen until the end.
Scene 3	The cell punch ruptures and
	burns, and the agent is
	released automatically with	950	It is observed that	The voltage is 0 V,
	time intervals for multiple		the unburned	and the battery is
	times. It can be seen that the		duration is 90	seriously cracked
	flame lasts for about 3		min, and the	with obvious splits.
	seconds, and a high-speed off-		burning torch is
	gas is generated. It can be		extinguished in
	seen that the interior is like		three tests
	live coal, and no flame is
	seen. The pressure relief plate
	bounces with time intervals.
	The disturbance in the box
	gradually calms down.

Effect Example 5: The effect data of the safeguard agent in Example 5 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	The agent is released totally,	1500	It is observed that	The voltage of one
	and then a cell is penetrated. It		the unburned	cell is 0 V, the
	can be seen that sparks are		duration is 10	voltage of the
	ejected, but no flame is seen.		minutes, and the	adjacent one is 2.1
	The casing of the penetrated		burning torch in	V, and the
	cell turns red, and no burning is		the test is still	remaining 7 pcs
	seen until the end.		extinguished	are available at 4.2
				V.
Scene 2	The agent is sprayed once in	2350	It is observed that	The voltage is 0 V,
	advance, then the cell is		the unburned	the shape does not
	penetrated, and then the agent is		duration is 90	change
	released automatically with		min, and the	significantly, and
	time intervals. The cell		burning torch is	the bottom cell
	generates a large amount of off-		extinguished in	film is not melted
	gas with violent disturbance,		three tests
	and a small amount of gas
	overflows from the gap in the
	box, a few sparks can be seen,
	and no flame is seen until the
	end.
Scene 3	The cell punch ruptures and	1000	It is observed that	The voltage is 0 V,
	burns, and the agent is released		the unburned	and the battery is
	automatically with time		duration is 90	seriously cracked
	intervals for multiple times. It		min, and the	with obvious
	can be seen that the flame lasts		burning torch is	splits.
	for about 4 seconds, and a high-		extinguished in
	speed off-gas is generated. It		three tests
	can be seen that the interior is
	like live coal, and no flame is
	seen. The pressure relief plate
	bounces with time intervals.
	The disturbance in the box
	gradually calms down.

Effect Example 6: The effect data of the safeguard agent in Example 6 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	A cell is penetrated, and the	1300	It is observed that	The voltage of one
	agent is released at the same		the unburned	cell is 0 V, the
	time, which is sprayed		duration is 10	voltage of the
	multiple times. It can be seen		minutes, and the	adjacent one is 0.47
	that sparks are ejected and the		burning torch in	V, the voltage of the
	casing of the penetrated cell		the test is still	other adjacent one is
	turns red, and no burning is		extinguished	1.36 V, and the
	seen until the end.			remaining 6 pcs are
				available at 4.2 V.
Scene 2	When the cell is penetrated,	2000	It is observed that	The voltage is 0 V,
	the agent is released		the unburned	the shape does not
	automatically with time		duration is 90	change significantly,
	intervals for multiple times.		minutes, and the	and the bottom cell
	The cell generates a large		burning torch is	film is not melted
	amount of off-gas with violent		extinguished in
	disturbance, and a small		three tests
	amount of gas overflowes
	from the gap in the box, a few
	sparks can be seen, and no
	burning is seen until the end.
Scene 3	The cell punch ruptures and	850	It is observed that	The voltage is 0 V,
	jets fire, and the agent is		the unburned	and the battery has
	released totally. It can be seen		duration is 90	obvious splits.
	that the flame lasts for about 2		min, and the
	seconds, and a high-speed off-		burning torch is
	gas is still generated after the		extinguished in
	fire is extinguished. It can be		three tests
	seen that the interior is like
	live coal, and the pressure
	relief plate bounces many
	times in the early stage. The
	disturbance in the box
	gradually calms down, and no
	burning is seen until the end.

Effect Example 7: The effect data of the safeguard agent in Example 7 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	A cell is penetrated with a nail,	2000	It is observed that	The voltage of
	and appeared thermal runaway		the unburned	one cell is 0 V,
	and deflagration. The agent is		duration is 15	the voltage of the
	released totally. The burning		minutes, and the	adjacent three are
	disappears instantly and lasts for		burning torch in	0.39 V, 0.72 V
	1 second. The casing of the		the test is still	and 1.95 V, and
	penetrated cell turns red and		extinguished	the remaining
	then gradually darkens, and no			5 pcs are available
	burning is seen until the end.			at 4.2 V.
Scene 2	After the cell is penetrated and	3150	It is observed that	The voltage is 0
	deflagration is visible, the agent		the unburned	V, the shape has
	is released automatically with		duration is 120	obvious splits,
	time intervals, and the burning		minutes, and the	and the bottom
	lasts for 3 s and extinguishes.		burning torch is	cell film is melted
	The cell generates a large		extinguished in
	amount of off-gas with violent		three tests
	disturbance, and gas overflows
	from the gap in the box, and no
	burning is seen until the end.
Scene 3	When the cell punch ruptures,
	the agent is released	1350	It is observed that	The voltage is 0
	automatically with time intervals		the unburned	V, and the battery
	for multiple times. The sparks		duration is 120	has obvious
	are ejected, and no burning is		min, and the	splits.
	seen. A high-speed off-gas is		burning torch is
	generated. It can be seen that		extinguished in
	the interior is like live coal, and		three tests
	the pressure relief plate bounces
	frequently in the early stage.
	The disturbance in the box
	gradually calms down. No
	burning is seen until the end.

Effect Example 8: The effect data of the safeguard agent in Example 8 for scene 1, 2 or 3

	Suppression mode and	Agent	Unburned
NO.	phenomenon description	dose g	duration	Battery test
Scene 1	A cell is penetrated, and the	2200	It is observed that	The voltage of one
	agent is released at the same		the unburned	cell is 0 V, the
	time, which is sprayed multiple		duration is 15	voltage of the
	times. It can be seen that sparks		minutes, and the	adjacent one is 1.2
	are ejected, but no flame is		burning torch in	V, and the
	seen. It can be seen that the		the test is still	remaining 7 pcs are
	casing of the penetrated cell		extinguished	available at 4.2 V.
	turns red, and no burning is
	seen until the end.
Scene 2	When the cell is penetrated, the	3500	It is observed that	The voltage is 0 V,
	agent is released automatically		the unburned	the shape does not
	with time intervals for multiple		duration is 120	change
	times, and a few sparks can be		minutes, and the	significantly, and
	seen. The cell generates a large		burning torch is	the bottom cell
	amount of off-gas with violent		extinguished in	film is not melted
	disturbance, and gas overflows		three tests
	from the gap in the box, and no
	burning is seen until the end.
Scene 3	When the cell is about to	1500	It is observed that	The voltage is 0 V,
	rupture due to serious swelling,		the unburned	and the battery has
	the agent is sprayed in advance,		duration is 120	obvious splits.
	and then the agent is released		minutes, and the
	automatically with time		burning torch is
	intervals. Sparks are ejected,		extinguished in
	no burning is seen, and high-		three tests
	speed off-gas is generated, and
	it can be seen the interior is like
	live coal. The pressure relief
	plate bounces frequently in the
	early stage. The disturbance in
	the box gradually calms down.
	No burning is seen until the
	end.

Claims

1. A safeguard agent, consisting of component A and component B; the component A is selected from one or more of a C5-C8 perfluoroalkane, a C5-C7 perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C5-C8 fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms, a C4-C7 perfluoroketone, a C4-C7 fluoroether, a C2-C6 perfluorocyclic ether which is unsubstituted or substituted by one or more C1-C3 perfluoroalkyl groups and heptafluoro-2-(1,2,2-trifluoroethyleneoxy)propane; the C4-C7 fluoroether contains at least 7 fluorine atoms; the component B is a C3-C5 bromofluoroalkene and/or a C2-C4 iodofluoroalkane; the bromofluoroalkene contains at least 2 fluorine atoms; the C2-C4 iodofluoroalkane contains at least 4 fluorine atoms;the molar ratio of the component A to the component B is 1:(1-4).

2. The safeguard agent according to claim 1, wherein the safeguard agent satisfies one or more following conditions: (1) the safeguard agent is a cooling suppressant or an extinguishant;(2) the safeguard agent is used in a walled space, a sealed space or an enclosure, such as the walled space or the enclosure;(3) the safeguard agent is used to protect a battery or suppress energy that is continuously released from the battery during thermal runaway;(4) the molar ratio of the component A to the component B is 1:(2-4), such as 1:3;(5) the C2-C4 iodofluoroalkane contains one iodine atom;(6) the C3-C5 bromofluoroalkene contains one bromine atom;(7) the C5-C8 perfluoroalkane is selected from perfluorohexane and/or perfluoroheptane;(8) the C5-C8 fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms is decafluoropentane and/or monohydrotridecafluorohexane;(9) the C5-C7 perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups is dodecafluorocyclohexane and/or perfluoromethylcyclopentane;(10) the C4-C7 perfluoroketone contains 1 or 2 carbonyl groups;(11) the C4-C7 fluoroether contains 1 or 2 oxygen atoms;(12) the C2-C6 perfluorocyclic ether which is unsubstituted or substituted by one or more C1-C3 perfluoroalkyl groups contains one oxygen atom;(13) the C3-C5 bromofluoroalkene is selected from one or more of 3-bromo-3,3-difluoropropene, 2-bromo-3,3,3-trifluoropropene, 3-bromo-1,1,3,3-tetrafluoropropene, 2-bromo-3,3,4,4,4-pentafluoro-1-butene, 2-bromo-3,4,4,4-tetrafluoro-3-(trifluoromethyl)but-1-ene and 2-bromo-3,3,4,4,5,5,5-octafluoro-1-pentene;(14) the C2-C4 iodofluoroalkane is selected from one or more of 1,1,1,2-tetrafluoro-2-iodoethane, iodo-1,1,2,2-tetrafluoroethane and iodoperfluorobutane;(15) the boiling point of the component A is 20-85° C.;(16) the boiling point of the component B is 30-80° C.;(17) the molecular weight of the component A is 200-400 g/mol;(18) the molecular weight of the component B is 150-400 g/mol;(19) the latent heat of vaporization of the component A is 21.6-34.4 kJ/mol;and (20) the latent heat of vaporization of the component B is 24.2-33.2 kJ/mol.

3. The safeguard agent according to claim 2, wherein the safeguard agent satisfies one or more following conditions: (1) the battery is a battery that releases energy in seconds when thermal runaway occurs;(2) the perfluorohexane is perfluoro-n-hexane, perfluoro-2-methylpentane or perfluoro-2,3-dimethylbutane;(3) the perfluoroheptane is perfluoro-n-heptane;(4) the C5-C8 fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms is

4. The safeguard agent according to claim 3, wherein the safeguard agent satisfies one or more following conditions: (1) the battery is a lithium-ion battery that releases energy in seconds when thermal runaway occurs; the lithium-ion battery is preferably a ternary lithium battery, a lithium-cobalt battery or a lithium manganese battery; or the lithium-ion battery is a prismatic battery, a pouch battery or a cylinder battery;(2) the release mode of energy release during thermal runaway is heat generation, gas generation, burning or explosion; the thermal runaway can be caused by internal short circuit or external short circuit of the battery, which can be simulatively induced through nail penetration or heating experiment;(3) the C4-C7 fluoroether is selected from one or more of

5. The safeguard agent according to claim 1, wherein (1) the safeguard agent is used to suppress heat generation, gas generation, burning or explosion caused by thermal runaway of a battery;(2) the component A is selected from a C5-C7 perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C4-C7 perfluoroketone, a C2-C4 perfluorocyclic ether which is unsubstituted or substituted by one or more C1-C3 perfluoroalkyl groups and a C4-C7 fluoroether; the C4-C7 fluoroether contains at least 7 fluorine atoms;(3) the component B is selected from a C3 bromofluoroalkene and/or a C4 iodoperfluoroalkane;and (4) the safeguard agent is a homogeneous liquid.

6. The safeguard agent according to claim 1, wherein the safeguard agent satisfies one or two of the following conditions: (1) the component A is selected from one or more of

7. The safeguard agent according to claim 1, wherein the safeguard agent adopts scheme 1, scheme 2, scheme 3, scheme 4, scheme 5, scheme 6, scheme 7 or scheme 8

8. A safeguard agent, consisting of component A and component B; and the latent heat of vaporization of the component A is 21.6-34.4 kJ/mol; the latent heat of vaporization of the component B is 24.2-33.2 kJ/mol; the boiling point of the component A is 20-85° C.; the boiling point of the component B is 30-80° C.; the number of fluorine atoms of the compound in the component A is 7-16, and the number of carbon atoms of the compound in the component A is 4-8; the compound in the component B contains at least one bromine or iodine atom; the number of hydrogen atoms of the compound in the component A is 0-5; the molecular weight of the component A is 200-400 g/mol; the molecular weight of the component B is 150-400 g/mol; the molar ratio of the component A to the component B is 1:(1-4).

9. The safeguard agent according to claim 8, wherein the safeguard agent satisfies one or two of the following conditions: (1) the component A is selected from one or more of a C5-C8 perfluoroalkane, a C5-C7 perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C5-C8 fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms, a C4-C7 perfluoroketone, a C4-C7 fluoroether, a C2-C6 perfluorocyclic ether which is unsubstituted or substituted by one or more C1-C3 perfluoroalkyl groups and heptafluoro-2-(1,2,2-trifluoroethyleneoxy)propane; the C4-C7 fluoroether contains at least 7 fluorine atoms;and (2) the component B is a C3-C5 bromofluoroalkene and/or a C2-C4 iodofluoroalkane; the bromofluoroalkene contains at least 2 fluorine atoms; the C2-C4 iodofluoroalkane contains at least 4 fluorine atoms.

10. The safeguard agent according to claim 9, wherein the safeguard agent satisfies one or more following conditions: (1) the safeguard agent is a cooling suppressant or an extinguishant;(2) the safeguard agent is used in a walled space, a sealed space or an enclosure, such as the walled space or the enclosure;(3) the safeguard agent is used to protect a battery or suppress energy that continuously releases from the battery during thermal runaway;(4) the molar ratio of the component A to the component B is 1:(2-4), such as 1:3;(5) the C2-C4 iodofluoroalkane contains one iodine atom;(6) the C3-C5 bromofluoroalkene contains one bromine atom;(7) the C5-C8 perfluoroalkane is selected from perfluorohexane and/or perfluoroheptane;(8) the C5-C8 fluoroalkane containing 1, 2, 3 or 4 hydrogen atoms is decafluoropentane and/or monohydrotridecafluorohexane;(9) the C5-C7 perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups is dodecafluorocyclohexane and/or perfluoromethylcyclopentane;(10) the C4-C7 perfluoroketone contains 1 or 2 carbonyl groups;(11) the C4-C7 fluoroether contains 1 or 2 oxygen atoms;(12) the C2-C6 perfluorocyclic ether which is unsubstituted or substituted by one or more C1-C3 perfluoroalkyl groups contains one oxygen atom;(13) the C3-C5 bromofluoroalkene is selected from one or more of 3-bromo-3,3-difluoropropene, 2-bromo-3,3,3-trifluoropropene, 3-bromo-1, 1,3,3-tetrafluoropropene, 2-bromo-3,3,4,4,4-pentafluoro-1-butene, 2-bromo-3,4,4,4-tetrafluoro-3-(trifluoromethyl)but-1-ene and 2-bromo-3,3,4,4,5,5,5-octafluoro-1-pentene;and (14) the C2-C4 iodofluoroalkane is selected from one or more of 1,1,1,2-tetrafluoro-2-iodoethane, iodo-1,1,2,2-tetrafluoroethane and iodoperfluorobutane.

11. The safeguard agent according to claim 10, wherein the safeguard agent satisfies one or more following conditions: (1) the battery is a battery that releases energy in seconds when thermal runaway occurs;(2) the perfluorohexane is perfluoro-n-hexane, perfluoro-2-methylpentane or perfluoro-2,3-dimethylbutane;(3) the perfluoroheptane is perfluoro-n-heptane;

12. The safeguard agent according to claim 11, wherein the safeguard agent satisfies one or more following conditions: (1) the battery is a lithium-ion battery that releases energy in seconds when thermal runaway occurs; the lithium-ion battery is preferably a ternary lithium battery, a lithium-cobalt battery or a lithium manganese battery; or the lithium-ion battery is a prismatic battery, a pouch battery or a cylinder battery;(2) the release mode of energy release during thermal runaway is heat generation, gas generation, burning or explosion; the thermal runaway can be caused by internal short circuit or external short circuit of the battery, which can be simulatively induced through nail penetration or heating experiment;(3) the C4-C7 fluoroether is selected from one or more of

13. The safeguard agent according to claim 8, wherein (1) the safeguard agent is used to suppress heat generation, gas generation, burning or explosion caused by thermal runaway of a battery;(2) the component A is selected from one or two of a C5-C7 perfluorocycloalkane which is unsubstituted or substituted by one or more trifluoromethyl groups, a C4-C7 perfluoroketone, a C2-C4 perfluorocyclic ether which is unsubstituted or substituted by one or more C1-C3 perfluoroalkyl and a C4-C7 fluoroether; the C4-C7 fluoroether contains at least 7 fluorine atoms;(3) the component B is selected from a C3 bromofluoroalkene and/or a C4 iodoperfluoroalkane;and (4) the safeguard agent is a homogeneous liquid.

14. The safeguard agent according to claim 8, wherein the safeguard agent satisfies one or two of the following conditions: (1) the component A is selected from one or more of

15. The safeguard agent according to claim 14, wherein the safeguard agent adopts scheme 1, scheme 2, scheme 3, scheme 4, scheme 5, scheme 6, scheme 7 or scheme 8

16. A thermal runaway suppressant or a fire suppressant comprising a mixture of the safeguard agent according to claim 1 and one or more extinguishants.

17. An extinguishing equipment comprising the safeguard agent according to claim 1 or the thermal runaway suppressant or the fire suppressant comprising a mixture of the safeguard agent according to claim 1 and one or more extinguishants.

18. A battery system comprising the safeguard agent according to of claim 1 or the thermal runaway suppressant or the fire suppressant comprising a mixture of the safeguard agent according to claim 1 and one or more extinguishants.

19. A safeguard agent system comprising one or more safeguard agent containers; when the safeguard agent system comprises a plurality of the containers, each container independently contains the component A according to claim 1 and/or the component B according to claim 1, respectively stored in the containers; the molar ratio of the component A to the component B in the containers is 1:(1-4);when the safeguard agent system comprises one container, the component A and the component B according to claim 1 are stored in the container at a molar ratio of 1:(1-4).

20. A method for controlling thermal runaway comprising the following steps: releasing or releasing in advance the safeguard agent according to claim 1 to an object that has appeared thermal runaway or an object that is about to appear thermal runaway; alternatively, releasing or releasing in advance the component A and the component B respectively according to claim 1 to the object that has appeared thermal runaway or the object that is about to appear thermal runaway, wherein the molar rate ratio of the release of the component A to the component B is preferably 1:(1-4), more preferably 1:(2-4), such as 1:3.