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Electric vehicle (EV) fire accidents induced by the thermal runaway of li-ion batteries are increasingly frequent, and the fire dynamics of EVs parked in rows are still unclear. Hence the fire evolution process and characteristics of two parallel placed EVs were studied by analyzing the burning behaviors and thermal fields. The fire source was the battery pack of a battery electric vehicle (BEV). Results showed that the precursor to the BEV fire was the emission of white smoke from the chassis. Flames did not appear until the accumulated smoke exploded, and they engulfed both the EVs. The flame switched between momentum and buoyancy control on the vehicle scale. The maximums of the length and duration of the jet fires were determined. The maximum temperature of the EV fire was consistent with that of internal combustion engine vehicle (ICEV) fires, but the flame spread faster between the EVs compared to ICEVs. Pragmatic methods were proposed to quantify the fire evolution rate. The heat effect of the EV fire on humans was also quantitatively evaluated. These results provide a fundamental understanding of fire rules in a high EV concentration scenario. [ABSTRACT FROM AUTHOR]

Electric vehicle (EV) fires resulting from the thermal instability of high-energy lithium-ion batteries (LIBs) have become a significant hazard to public safety. Effective and prompt fire-fighting methods for dealing with EV fires are required. A fire protection method referred to as electric vehicle fire enclosure (EVFE) was proposed in this paper based on EV fire characteristics. Full-scale fire experiments were employed to evaluate the fire extinguishing efficiency of various types of EVFE. Results showed that EVFE could effectively suppress the thermal runaway (TR) of full-size LIB packs in the EVs under these experimental conditions, and the battery packs did not occur re-thermal runaway after EVFE stopped working. The agent consumption of water EVFE was 0.628 m3/kWh, while that of foam EVFE was 0.743 m3/kWh. Moreover, the overheated battery packs had an interesting TR propagation mechanism that TR discretely spread among the cells. The TR critical temperature of unconnected battery modules was not suitable for illustrating the TR characteristics of circuit-connection battery modules. For the full-size LIB packs, the TR onset temperature ranged from 31.8 °C to 117.3 °C. These results provide an insight into the fire protection methods and TR characteristics of the LIB packs in EVs. • A new fire protection method for dealing with electric vehicle fires is proposed. • The fire extinguishing performance of the method is evaluated by full-scale fire tests. • An interesting thermal runaway propagation mechanism is found in full-size lithium-ion battery packs. • The thermal runaway onset temperature of cells in the battery packs is between 31.8 °C and 117.3 °C. [ABSTRACT FROM AUTHOR]