Experimentally exploring prevention of thermal runaway propagation of large-format prismatic lithium-ion battery module

Thermal runaway (TR) propagation was considered to be the utmost safety issue in the application of lithium-ion batteries (LIBs) due to the high risk of fire or explosion, which raised extensive concerns. However, the scientific knowledge of TR propagation prevention on batteries with high capacity is still lacking. In this study, TR propagation behaviors in the large-format battery module were investigated through experiments. In addition, the effects of thermal insulation (aerogel) and a couple of thermal insulation and phase change material (PCM) on the inhibition mechanism of TR propagation were identified. An increasing tendency in maximum temperatures and peak mass-loss rates of batteries was observed with the proceeding of TR propagation, which was attributed to the pre-heating effect. During TR propagation, the energy released by the TR battery was responsible for the triggering of TR in its adjacent battery, accounting for more than 65%. Inserting the aerogel between adjacent batteries can effectively inhibit the propagation of TR, but easily resulted in the accumulation of thermal energy in the battery module. Compared with the insertion of the aerogel, coupling the thermal insulation of aerogel and the heat latent of PCM not only promoted the performance in preventing TR propagation, but also enhanced the heat dissipation capacity of the battery module. These findings provide deeper insights into TR propagation mechanisms and verification of the effectiveness of the combination of aerogel and PCM in quenching TR propagation, holding an enormous promise for the safer battery module.