Prediction and Correction of LFL for Multicomponent Gases Relevant to Lithium-Ion Battery Thermal Runaway

The lower flammability limit (LFL) is critical for assessing ignition and explosion risks associated with lithium-ion battery thermal runaway gases. In this study, a primary experimental LFL database containing 58 data points for H2–CO–CH4–C2H4–CO2–N2–O2 mixtures was compiled from the first author’s publicly available doctoral dissertation. Le Chatelier’s rule was first evaluated as a baseline model, and its prediction residuals were then corrected using a five-coefficient data-driven model based on physically interpretable variables, including total diluent fraction, CO2 fraction in diluent gases, oxygen fraction, and the interaction between highly reactive fuels and dilution. Results showed that Le Chatelier’s rule provided a useful first-order estimate but systematically underestimated LFL under high-dilution and CO2-rich conditions. The proposed correction model reduced the mean absolute error from 2.40% to approximately 1.00% while retaining an explicit mathematical form. This experimental-data-driven framework provides a preliminary and interpretable tool for rapid LFL estimation of multicomponent gases relevant to battery thermal runaway risk assessment.