基于相变材料的锂离子电池热失控分级抑制

Grading inhibition of thermal runaway of lithium ion battery based on phase change materials

基于锂离子电池组高温热失控过程,分析电池热失控过程的热参数变化特征。针对50、100℃两个温度节点,采用石蜡-膨胀石墨-活性炭、聚乙二醇1500-甲基纤维素的两级相变材料,以弧形铝蜂巢板作为载体,提出一种基于相变材料的预防锂离子电池组高温热失控的分级抑制方法。常温常压条件下,以3节锂离子电池并联外短路放电对相变材料有效性进行测试,与未应用两级相变材料的电池组相比最大温差可达446℃,验证了两级相变材料的有效性。

Based on high temperature thermal runaway process of lithium ion battery pack,thermal parameters variation characteris⁃tics during the thermal runway were analyzed.Selecting the tem⁃peratures of 50℃and 100℃,taking paraffin-expanded graphiteactivated carbon and PEG1500-methyl cellulose as two levels of phase change materials(PCM),the grading inhibition method to prevent the high temperature thermal runaway of the lithium ion battery was put forward.Curved aluminum honeycomb board was used as the carrier.Under normal temperature and pressure,the ef⁃fectiveness of phase change materials was tested by external short circuit of three lithium-ion batteries in parallel.The maximum tem⁃perature difference is 446℃compared with the batteries without two-stage phase change materials.The validity of the two-stage phase change material is verified.