基于火探管式的锂离子电池灭火技术研究

Development of fire suppression technology for lithium ion batteries based on fire detection pipe

为研究锂离子电池灭火方案,基于火探管灭火技术同时利用新型清洁灭火剂Novec 1230,组装成火探管灭火系统。在灭火测试平台上以功率为200 W的电热管作为外热源引发单电池或电池模组热失控,通过改变火探管的布置位置,记录相应的灭火行为以及灭火效率,并对实验结果进行了分析。研究结果表明,当火探管灭火系统直接布置在电池正上方时,在起火后的5.6s内控制火情;随着灭火剂用量增加可以显著降低体系温度,防止电池复燃以及连锁热失控现象发生;火探管有效覆盖区域外的失控电池作为热源将继续加热临近电池,引发连锁热失控,造成灭火系统失效;根据电池热失控后的燃烧行为以及传热行为,提出相应的火探管灭火系统复合方案。

Developing an efficient fire suppression technology is an essential aspect of consummating lithium ion battery safety.In this study,a new and clean extinguishing agent named as dodecafluoro-2-methylpentan-3-one was applied to lithium ion battery systerm by combining with fire detection pipe technology.This fire suppression technology is presented according to the thermal runaway behavior and heat transfer process of lithium ion battery.Thermal runaway of a single battery or battery module was triggered by a 200 W electric tube as the external heat source to verify the effectiveness of this fire suppression technology according to the recorded fire behavior and fire extinguishing efficiency.Results show that battery fire can be controlled within 5.6 s after the ignition when the fire detection pipe was arranged directly above the battery.Furtherly,with the increase of the fire extinguishing agent usage,the temperature of the system can be significantly reduced and reignition and the spread of thermal runaway can be prevented.But for batteries outside the protection area of the fire detection pipe,they will continue to heat other batteries and then trigger the spread of thermal runaway,resulting in fire extinguishing system failure.