This study investigates the suppression of lithium-ion battery (LIB) fires using
composite aqueous extinguishing agents, with a 20 Ah lithium iron phosphate
battery as the experimental subject. Based on the functional selection of
coverage-isolation and cooling-smothering, three aqueous extinguishing agents,
S-E-1, S-E-2, and S-E-3, were designed and developed using hydrocarbon
surfactants. The results indicate that all three aqueous fire extinguishing
agents can effectively suppress LIB fires. Through a comprehensive evaluation of
extinguishing time, cooling rate during extinguishing agent release, and
physical and chemical parameters of the extinguishing agents, the optimal
formulation was determined to be 2% SDS (sodium dodecyl sulfate), 1% SDBS
(sodium dodecyl benzene sulfonate), 3.5% CAB (cocamidopropyl betaine), 1%
APG0810 (alkyl polyglycoside), 1% CDEA (coconut oil acid diethanolamine), 0.32%
CH4N2O (urea), 1.5%
NH4H2PO4 (ammonium dihydrogen phosphate),
0.5% C2H6O2 (glycol), 1.5%
Na3PO4 (sodium phosphate), and deionised water,
demonstrated the best performance. Reducing the extinguishing time to 14
seconds, a 41.7% reduction compared to pure water, and increasing the cooling
rate to 0.816 °C·s^–1, which is 4.4 times that of pure water, with no
reignition observed. This work contributes to the theoretical principles needed
to engineer next-generation fire suppression materials for lithium-ion batteries
that are both efficient and eco-friendly.