Preparation and application of perfluorohexanone O/W microemulsion in suppressing lithium battery thermal runaway

Abstract

Lithium-ion battery (LIB) is often capable of causing great harm in the event of a fire, and existing extinguishing agents are unable to achieve fast, efficient, convenient and low-cost suppression of thermal runaway in LIB. This paper, based on the theory of microemulsions, has formulated a cost-effective perfluorohexanone O/W microemulsion by selecting the surfactant C₁₅H₄F₁₉NaO₄S and the co-surfactant C₂H₅OH. Molecular dynamics simulations showed that the OBS molecule adsorbs C₆F₁₂O through its fluorine-containing hydrophobic group, while its hydrophilic group interacts with the hydroxyl group of C₂H₅OH and adsorbs water molecules at the same time, resulting in the spontaneous formation of stable microemulsion systems. The fire suppression characteristics of this microemulsion on LIB fires are investigated using a self-built experimental platform. Experimental results show that perfluorohexanone O/W microemulsion can significantly reduce the flame temperature of LIB spraying by about 51 % in synergy with N₂, and at the same time, absorb the toxic and harmful gases through the release of the foam formed, and effectively reduce the concentration of CO by 43 % and the concentration of SO₂ by 65 %. Compared with C₆F₁₂O and water mist extinguishing agents, it demonstrates a more pronounced fire suppression effect. This research provides a valuable reference for the development of efficient, economical, and environmentally friendly LIB extinguishing agents, contributing to advancements in fire safety technology for LIB.