Development of thermal runaway propagation model considering vent gas combustion for electric vehicles

Abstract

A vent gas thermal runaway propagation model(VTRP) was developed for module scale application in electric vehicle. The VTRP model consists of an internal thermal abuse model and the vent gas model. The vent gas model presented the characteristics of vent gas generation in terms of cell temperature. To improve the accuracy of vent gas combustion heat, the hydrogen and VOC ratio was considered in terms of cell temperature. The VTRP model was validated at module scales. VOC is mainly formed around 90–150 °C, while H2 increases rapidly in temperatures over 175°C. Especially, the convective heat transfer by VOC and H2 combustion plays an important role in the propagation of thermal runaway. Moreover, the heat release rate and flow around the vehicle were properly predicted on the EV scale. Also, it was found that it had to withstand about 120°C to prevent fire propagation between vehicles in the parking lot. The VTRP model proposed in this study should be usefully to predict a number of thermal runaway phenomena including vent gas combustion.