环境温度对锂离子电池爆炸参数影响

Influence of environment temperature on explosibility parameters of lithium-ion batteries

为探究在不同环境温度下锂离子电池触发热失控后的燃爆危险性,利用改进的20-L球装置测试了锂离子电池在不同初始环境温度和加热功率下触发热失控后的爆炸参数,对爆炸后的气体取样并分析气体成分。结果表明,当初始环境温度为25℃时,随着加热功率增加,电池更早发生燃爆,最大压升速率增大,电池质量损失增大,损毁更为严重;当初始环境温度为60℃时,最大压升速率由14.41 MPa/s增加至29.12 MPa/s,表明初始环境温度对爆炸参数的测试结果有显著影响;当初始环境温度为95℃时,最大压升速率基本一致,最大压力略有下降;爆炸后的气体中均存在CO和H2,其体积分数随着初始环境温度的增加而增加,表明锂离子电池热失控产物并未充分燃烧。研究结果有助于更为全面地评估锂离子电池的燃爆危险性,为锂离子电池的安全防护提供数据参考。

Fires and explosions from thermal runaway of lithium-ion batteries(LIBs)are serious threats.To investigate the explosibility parameters of LIBs at various initial temperatures and heating power,a modified Siwek 20-L apparatus was used.The results show that when the initial temperature is 25℃,the maximum pressure rise rate increased,the battery mass loss and damage become more severe,while the maximum surface temperature of the cell decreased with increasing of heating power.When the initial temperature is 60℃,there is a sharp increase from 14.41 MPa/s to 29.12 MPa/s in the maximum pressure rise rate,indicating that the initial ambient temperature has a significant impact on the explosibility parameters.When the initial environmental temperature is 95℃,the maximum pressure rise rate is basically the same,and the maximum pressure slightly decreases.Through the composition analysis of the gas after explosion,it is found that the combustible gas generated by the LIB after thermal runaway was not completely burned due to insufficient oxygen in the chamber.CO and H2 were present in the chamber after the deflagration.Their volume fractions were higher with higher initial ambient temperature.The results contribute to a more comprehensive assessment of the explosion hazard and provide data reference for the safety protection of LIBs.