Abstract: Different from the conventional ambient-temperature jet fires caused by fuel leakage in previous studies, the high-temperature combustible gas ejected during lithium-ion battery thermal runaway poses a higher fire risk. In this study, copper foam was proposed to reduce the temperature of high-temperature combustible gas and suppress the formation of jet fires, with methane jet fire adopted for experimental verification. The results showed that the 10 ppi copper foam could reduce the temperature of high-temperature combustible gas to 481 ℃, exhibiting excellent suppression and extinction performance on methane jet fires. The 20 ppi and 40 ppi copper foams also effectively reduced the gas flow temperature; however, the relatively high flow resistance induced lateral deflection of the flame, which posed a risk of heating the battery. Regarding the heat absorbed by copper foam from high-temperature combustible gas, the first 35 s were mainly consumed for self-heat storage of the copper foam, and after 35 s, the heat was mainly dissipated into the environment through external radiation. The effective suppression and extinction time of copper foam on methane jet fire exceeded 100 s.

Key words: lithium-ion battery, jet fire, copper foam, pore density, fire suppression performance