纳米纤维材料对锂电池热失控传播影响研究

Effect of nanofiber material on thermal runaway propagation of lithium battery

锂电池在运输以及使用过程中的磕碰、外短路等原因造成的热失控极易诱发周边电池升温,导致热失控蔓延。为控制锂电池热失控传播,本文使用纳米纤维材料对热量传播进行抑制,以瓦楞纸、陶瓷纤维和玻璃纤维作为间隔材料展开锂电池热失控试验,从隔热性和耐火性两方面对隔热材料进行评估。结果表明:虽然纳米纤维材料的保温性能会促使首节电池更快进入热失控状态,但由于其良好的隔热性能,锂电池热失控的传播可以被有效抑制。对首节电池燃爆过程中隔热材料的热流密度进行测算,发现陶瓷纤维纸的热通量峰值更低,纳米纤维材料的隔热性能要优于瓦楞纸。同时对3种材料耐火性进行试验,判定电池燃爆时材料的可靠性,发现瓦楞纸极易燃烧,而纳米纤维材料具有良好的热稳定性。结果证明了纳米材料作为锂电池运输间隔材料的可行性。

The thermal runaway of lithium battery caused by bumping and external short circuit during transportation and use is very easy to induce the surrounding batteries to heat up,leading to the spread of thermal runaway.In order to control the thermal runaway propagation of lithium batteries,this paper uses nanofi⁃ber materials to inhibit heat propagation,and uses corrugated pa⁃per,ceramic fiber and glass fiber as spacer materials to carry out the thermal runaway test of lithium batteries,and evaluates the in⁃sulation materials in terms of heat insulation and fire resistance.The results show that although the thermal insulation perfor⁃mance of the nanofiber material will prompt the first battery to en⁃ter the thermal runaway state faster,the propagation of the ther⁃mal runaway of the lithium battery can be effectively suppressed due to its good thermal insulation performance.The heat flux den⁃sity of the thermal insulation materials during the combustion ex⁃plosion of the first battery is measured,and it is found that the peak heat flux of ceramic fiber paper is lower,and the thermal in⁃sulation performance of nanofiber materials is better than that of corrugated paper.At the same time,the fire resistance of the three materials was tested to determine the reliability of the mate⁃rials during the battery explosion,and it was found that the corru⁃gated paper was very easy to burn,while the nanofiber material had good thermal stability.The results demonstrate the feasibility of nanomaterials as transportation spacers for lithium batteries.