Modeling Analysis of Thermal Runaway Propagation and Mitigation in a Large-Format Lithium-Ion Battery Module

A thermal abuse model of a single lithium-ion battery, coupling the electric–chemical reaction model and heat transfer model condition, is presented in this work to predict the battery’s thermal response. This model was validated by the experimental results, and it was found that it can predict the battery’s thermal runaway in adiabatic conditions well. It was found that a local hot spot is formed first on the cell nearest the air gap inside the battery. A thermal runaway propagation model was constructed based on this thermal abuse model of a single battery. In addition, the effect of four different modes on the mitigation of thermal runaway propagation is also discussed, including the air gap, cooling plate and insulation layer. The thermal runaway propagation event is successfully prevented when the aerogel is placed between adjacent batteries. However, low-thermal-conductivity insulation material has a negative effect on the heat sink of the battery in thermal runaway, which may aggravate this behavior. This study demonstrates that the model can be used to predict thermal runaway propagation event in battery modules with different prevention measures, and also contributes to the design of safe lithium-ion battery systems.