Efficiency of dodecafluoro-2-methylpentan-3-one microemulsion to inhibit thermal runaway in lithium-ion batteries

Under abusive conditions, lithium-ion battery (LIB) are prone to thermal runaway (TR), which can result in fire and explosion, even toxic. A water-in-oil dodecafluoro-2-methylpentan-3-one (C₆F₁₂O) microemulsion was created in this study by emulsifying C₆F₁₂O as the oil phase with a fluorocarbon surfactant, sodium perfluorooctanoate, and a co-surfactant, perfluorobutanol, and encapsulating the aqueous phase. In this paper, the combustion characteristics of 100% SOC LIB and the fire extinguishing experiments of various inhibitors such as microemulsions were carried out; the flame suppression effect, cooling effect and suppression of TR gas production effect of different extinguishing agents were explored; the synergistic suppression mechanism of C₆F₁₂O microemulsions on LIB fires was revealed. The experimental results show that C₆F₁₂O microemulsions can quickly and effectively extinguish LIB flames after release, and their fire extinguishing time is short, which can effectively reduce the generation of high temperature battery fumes and prevent battery re-ignition without short circuit risk. The microemulsion PM1 (61.2% C₆F₁₂O, 26.5% water, and the rest emulsifiers) was the most effective: compared with C₆F₁₂O and water, the cooling efficiency was enhanced by 156% and 28%, respectively, and the degree of TR inhibition was enhanced by 18.5% and 24.0%; and the release of cell gas production during inhibition was reduced.