Dry water: Toward an ideal extinguishant for lithium-ion battery fire

Developing an environment-friendly, high-cooling, non-conductive, and low-cost extinguishant has been the focus on fighting lithium-ion battery (LIB) fires. In this work, dry water (DW), a powdered material containing copious amounts of liquid water, was first studied as an extinguishant for LIB fires. Benefiting from the core-shell structure and dispersibility properties as a dry powder, DW shows a high electric breakdown voltage, which enables it to overcome the conductivity drawback of liquid water. Moreover, although the endothermic enthalpies of DWs are only about 82.4–95.7 % of liquid water, their water evaporation rates are faster than liquid water, which brings DWs a better cooling effect than liquid water in suppressing thermal runaway propagation. Thus, DW combines the advantages of both liquid water (high cooling ability) and dry powder (low conductivity), and presents a great application potential to control LIB fires.