Experimental analysis on comprehensive combustion performances of vehicle-level thermal runaway

Abstract

As the growing population of electric vehicles, the increasing fire accidents have drawn much attention both for researcher and society. Unfortunately, the real-conditional thermal runaway is hard to recurrent according to diverse inducements. The comprehensive combustion behaviors for vehicle-level fire accident are still confusing and should be further investigated, and the results will provide guidance on further improvement of vehicle safety or further applicational situation. In this article, a vehicle-level thermal runaway experiment is carried out with a commercial SUV, and multi-information is collected to determine the combustion behavior and fire spreading path including temperature, voltage and gases. The artificial arson is selected as the inducement for simulating the real-conditional accident, and 4 periods on fire burning are divided according to combustion behaviors. An interval of 12 mins before the battery thermal runaway can be observed and provide probability for roadside assistance. Moreover, the safe distance of possible harmful hazards is less than 10 m, and should be warning when designing underground parking. Then, Limited voltage decrease of 10 mV is recognized as early-warning information before battery thermal runaway, and the large voltage jump or characteristic temperature help for diagnostic of thermal runaway. Finally, the established experimental workbench delivers the potential solution for vehicle-level thermal runaway analysis, and can be promoted to other experiments under various inducements. The article highlights the whole process of fire spreading of electric vehicle and help to improve the safety of vehicles according to the results.