301 / 2024-03-15 09:59:53

Study on the thermal runaway and explosion characteristics of penetration-induced li-ion battery hazard in confined space

Li-ion battery; Thermal runaway; Penetration; Explosion; Gas release

2、安全工程与职业健康 > 5、应急技术与救援

The massive heat and gas release during li-ion battery (LIB) thermal runaway (TR) are the two main root causes for fire and explosion hazard. However, the characteristics of combustible gases release and explosion behaviors under various penetration conditions have not been comprehensively studied. In this work, the influence of penetration duration, penetration area, battery capacity, and ignition condition have been investigated with the large-format LIBs. Results show that the short circuit contributes minor heat generation, but can significantly accelerate the heat generation process during TR. An explanatory module has been illustrated to analyze the mechanism of penetration-induced TR, and the triggering of TR is closely related with the scale of initial penetration, where continuous short circuit should be formed. During the tests, the maximum normalized heat generation of 5.8 kJ/Ah can be obtained for the 280 Ah LIB. However, the normalized gas release presents contrary behaviors, and reaches the maximum of 0.35 L/Ah for the 100 Ah and 150 Ah LIBs. Violent explosion with a maximum overpressure of 285.3 kPa has been recognized with manually ignition, which is mainly contributed by consumption of the CO, CH₄, C₂H₄, and C₅H₁₂. The findings present positive significance on the underlying understanding of the TR and explosion behaviors during penetration, which is crucial for the TR and explosion suppression.