双相流细水雾抑制锂离子电池热失控蔓延试验研究

Experimental Study on the Suppress Effect of Biphasic Flow Water Mist on Thermal Runaway Propagation in Lithium Ion Batteries

为抑制锂离子电池热失控及其蔓延,构建氮气与细水雾(NWM)双相流系统.通过改变系统施加压强和作用时间,对比分析电池表面温度和附近烟气体积分数以及NWM的冷却功率和电池模块的热量累积,阐述NWM系统抑制锂离子电池模块热失控蔓延的机制及有效性.结果表明,在NWM冷却电池模块表面和窒息机制的协同作用下,电池模块射流火的持续时间显著降低;且NWM压强越大,作用时间越长,会使电池表面的最高温度越低,相邻电池之间TR蔓延的时间间隔越长,表明NWM抑制锂离子电池热失控蔓延的有效性显著增强.

To suppress the thermal runaway(TR)and its propagation in lithium-ion batteries,a nitrogen and water mist(NWM)biphasic flow system is constructed.By changing the pressure and duration of the system,comparing the surface temperature and the volume fraction of flue gas emitted from the batteries,and analyzing the cooling power of NWM and the heat accumulation in the battery module,the mechanism and effectiveness of NWM system in suppressing TR propagation in the lithium-ion battery module are studied.The results show that under the synergistic effect of NWM cooling the battery module surface and the suffocation mechanism,duration of the jet fire of the battery module is significantly reduced.Moreover,higher NWM pressure and longer duration of the system leads to lower peak temperature on the battery surface,and time intervals for TR propagation between adjacent batteries increases,demonstrating a significantly enhanced effectiveness of NWM in suppressing the propagation of TR in lithium-ion batteries.