Thermal Runaway Gas Generation of Lithium Iron Phosphate Batteries Triggered by Various Abusive Conditions

Abstract

Lithium iron phosphate (LFP) batteries are widely utilized in energy storage systems due to their numerous advantages. However, their further development is impeded by the issue of thermal runaway. This paper offers a comparative analysis of gas generation in thermal runaway incidents resulting from two abuse scenarios: thermal abuse and electrical abuse. The study initially focuses on 13-Ah lithium iron phosphate single-cell batteries. Experiments were conducted to induce thermal runaway through both forms of abuse, analyzing the production and dispersion of H2 and CO gases in each case. It was observed that thermal abuse–induced thermal runaway resulted in higher gas concentrations and more pronounced fluctuations, whereas electrical abuse–induced thermal runaway exhibited lower gas concentrations and lower fluctuations. Subsequently, key materials and temperature variations at the positive and negative electrodes were investigated under both types of thermal runaway, revealing distinct differences that are identified as the primary reasons for the significant disparities in H2 and CO gas generation during the two thermal runaway conditions. The conclusions drawn in this paper advance the understanding of the mechanisms underlying H2 and CO gas concentration generation in thermal runaway scenarios.