Impact of humidified water mist on thermal runaway characteristics of lithium-ion batteries in a long-narrow confined space
Zhi Wang, Xianyu Yu, Qingjie Zhao, Qingying Cheng, Bobo Shi
Abstract
Thermal runaway (TR) in lithium-ion batteries (LIBs) poses a significant fire and explosion risk, especially in long-narrow confined spaces. This study experimentally investigates the effect of humidified water mist on the TR behavior of LIBs in a long-narrow confined space. The results reveal a dual-action mechanism of humidified water mist on TR characteristics, identifying a critical mass flow rate. When the mass flow rate of humidified water mist is below 1.4 g/min, it effectively reduces peak temperatures and delays the onset of TR, demonstrating a significant suppression effect. However, as the flow rate exceeds this threshold, the suppression effect reverses, intensifying TR characteristics and indicating a complex, non-linear relationship between humidified water mist and TR dynamics in confined spaces. Additionally, the maximum ceiling temperature in this space was analyzed, and a predictive model of temperature decay was developed, clarifying the environmental TR hazard posed by the cell. Finally, the heat loss of LIBs in each scenario is calculated, elucidating the mechanism of humidified water mist affecting TR of the cell. These findings offer a practical approach to reducing TR risk in LIBs applications in confined environments.