考虑电解液汽化的280Ah LiFePO4棱柱形电池热失控行为的实验与建模研究

Abstract LiFePO 4 batteries are frequently used in energy storage stations, and their potential thermal runaway behavior poses a threat to the safety of these stations. The thermal runaway behavior of large-capacity LiFePO 4 batteries exhibits three-dimensional propagation characteristics, and the boiling of electrolyte complicates the heat transfer behavior within the battery , hindering the design of highly thermal safe batteries. This paper uses models to quantify and visualize the endothermic vaporization and heat transfer process of the electrolyte. Comprehensive tests, including heat generation, gas production, internal pressure, electrolyte phase change, venting mass flow rate, and venting gas composition, were conducted to provide input for the model. In the comparison between the model and experimental results, the coefficient of determination for the battery front surface temperature is 0.9258, and that for the battery back surface temperature is 0.9046. After the safety valve is opened, there is a 7°C difference between the experimental and simulated results of the endothermic vaporization of the electrolyte. Accurate temperature calculation will improve the reliability of thermal runaway insulation design for battery modules.