Fire Inhibition Mechanism of C 6 F 12 O on Li‐Ion Battery Thermal Runaway Vent Gas: A Reactive Force‐Field Molecular Dynamics Study

The frequent occurrence of Li‐ion battery safety incidents involving Li‐ion batteries has raised concerns regarding the development of high‐efficiency fire extinguishing agents for Li‐ion battery fires. The primary cause of these fires is the gas produced during the thermal runaway of lithium‐ion batteries. The thermal runaway exhaust gas is selected as the research object in this article to reveal the fire extinguishing mechanism of C 6 F 12 O for Li‐ion battery combustion base on reactive force‐field molecular dynamics. The reaction process and quantity changes of fuel, important intermediates, and C 6 F 12 O are analyzed, and the main radical reactions of combustion inhibition are determined. The results show that C 6 F 12 O inhibits CH 4 , C 2 H 4 , H 2 from combustion reactions such as chain initiation and chain transfer reactions. Meanwhile, small carbon–fluorine groups decomposed by C 6 F 12 O, including F · , CF 3 · , C 3 F 7 · , CF 2 · , and CF · , react with fuel molecules to form important intermediates and stable products, including HF, CF 3 H, and C 3 F 7 H. The carbon–fluorine groups also react with the intermediates mainly involved combustion chain reaction, which further inhibits the development of the combustion process. In addition, the production of Li‐ion battery exhaust gas combustion products, such as H 2 O and CO 2 , is reduced. The research results not only reveal the inhibition mechanism of C 6 F 12 O on the combustion of Li‐ion battery, but also provide an important reference for the engineering application of C 6 F 12 O as a fire extinguishing agent for Li‐ion battery.