三元动力锂离子电池组热失控火灾危险性

Study on thermal runaway of ternary power Lithium ion battery module

针对电动汽车火灾事故中电池组热失控工况,对动力锂离子电池组进行封闭空间内外火加热和内部单体过充引燃实验,记录实验现象和温度变化。结果表明:电池组过充时箱体内最高温度升至10701且出现持续的喷射火焰,外火加热时箱体内最高温度为450 t:,无剧烈的喷火、冒烟现象;内部过充起火后电池组破坏程度远大于外部火源加热的情况。实验后电池组痕迹显示,过充引发的电池组整体热失控痕迹会具有较明显的由两侧向中心挤压的特征,单体的破坏程度由过充单体向远端依次递减。

Against with the thermal runaway condition of the battery pack in the electric vehicle fire accident,the ignition tests of the external lithium heat and the internal monomer overcharge in confined space were carried out on the power lithium ion battery pack,and the experimental phenomena and temperature changes were recorded.The results showed that the maximum temperature in the box rises to 1070℃ and there is continuous jet flame when the battery was overcharged.The maximum temperature in the box is 450℃ and there is no flame and smoke when the box is heated by external fire.After the experiment,the traces of the battery pack showed that the thermal runaway of the battery pack caused by overcharge has more obvious bilaterally-centered extrusion characteristics,in which the degree of destruction of the monomer was successively decreased from the overcharged monomer to the distal end.