锂离子电池热失控气体燃爆特征实验研究

Study on the characteristics of gas deflagration caused by the thermal runaway of Lithium-ion battery

为研究储能电站电池单元的火灾危险性,针对锂离子电池发生热失控后释放混合气体的爆炸危险性和火灾危险性进行实验研究,测定分析锂离子电池电解液的危险性以及不同环境气氛下锂离子电池的热失控特性。结果表明:按锂离子电池热失控释放主要气体组分配制的混合气体具有较大的爆炸危险性,爆炸下限为6.1%,最大爆炸压力可达0.61~0.76 MPa,可对建筑物造成严重破坏;配制的混合气体最小点火能为0.3 mJ。锂离子电池电解液在120~130℃温度下挥发蒸气危险性较高,爆炸下限为2.3%,且燃烧后产生的刺激性气体可能导致人体的二次伤害。实验采用三元锂电池热失控触发温度为125~150℃。研究结果可以为锂离子电池储能电站可燃气体探测、通风设计等提供支持。

This work experimentally studied the risk of the gas deflagration and the fire caused by the Lithium-ion battery in case that the thermal runaway happens in an energy storage system.Besides,the risk of the electrolyte under high temperature and the thermal runaway properties of the Lithium ion battery are also investigated.The results indicate that the gases caused by the thermal runaway of the lithium-ion battery performs a high deflagration level,and the lower explosive limit is about 6.1%.The maximum explosive pressure reaches to 0.61~0.76 MPa,which can cause severe damage to the building structure.Besides,the minimum ignition energy of the gases caused by the thermal runaway of the Lithium ion battery is only 0.3 mJ.The releasing gases of the electrolyte under 120~130℃ have a lower explosive limit of 2.3%,showing a high risk,which can also lead secondary damage to the human.It is shown that the activation temperature of the thermal runaway of the Lithiumion is between 125~150℃.The experimental results can provide guidance for the detection of the flammable gases and the design of the ventilation system in energy storage system.