锂离子电池箱爆炸危险性仿真及泄爆设计

Simulation of explosion hazard of Li-ion battery box and design of explosion venting

运用流体力学软件Fluent和爆炸模拟软件Flacs,对锂离子电池箱内气体爆炸危险性进行分析,得出不同扩散时间、不同点火位置、不同正极活性材料(LiFePO_(4)、LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2)和LiCoO_(2))电池和相同电池不同荷电状态(SOC)下电池箱内气体的爆炸特性和规律,在此基础上,对电池箱泄爆方式进行设计。最大爆炸危害对应时刻为10~20 s;中心点火比一侧点火的爆炸强度大;SOC越高的LiFePO_(4)锂离子电池,爆炸强度越大;不同正极活性材料电池热失控气体的爆炸超压与电池本身危险性关系不大;短侧双口和长侧单口的泄压效果较好,且短侧泄爆泄压面积越大,泄压效果越好。

The fluid mechanics software Fluent and explosion simulation software Flacs were used to analyze the risk of gas explosion in the Li-ion battery box,the explosion characteristics and laws of the gas in the battery box under different diffusion time,different positions of ignition,the battery with different cathode active materials(LiFePO_(4),LiNi_(0.8)Co_(0.15)Al_(0.05)O_(2),LiCoO_(2))and different states of charge(SOC)of the same battery were obtained.On this basis,the explosion venting method of the battery box was designed.The maximum gas explosion hazard corresponding time was 10-20 s.The explosive intensity of the center ignition was greater than that of one side ignition.The higher the SOC,the greater the explosion intensity of the LiFePO_(4)Li-ion battery.The overpressure of the thermal runaway gas explosion of battery with different cathode active materials had little to do with the danger of the battery itself.The double-port on the short side and the single-port on the long side had better pressure relief effects,the larger the short side explosion relief area,the better the pressure relief effect.