磷酸铁锂离子电池热失控产物爆炸下限预测方法  

Prediction methods for lower explosion limit of thermal runaway products of lithium-iron phosphate batteries

作　　者：袁帅 台枫 钱新明[2] 程东浩 YUAN Shuai;TAI Feng;QIAN Xinming;CHENG Donghao(China Academy of Civil Aviation Science and Technology,Beijing 101399,China;Sate Key Laboratory of Explosion Science and Safety Protection,Beijing Institute of Technology,Beijing 100081,China;Engineering and Technical Research Center of Civil Aviation Safety Analysis and Prevention of Beijing,Beijing 100028,China)

机构地区：[1]中国民航科学技术研究院,北京101399 [2]北京理工大学爆炸科学与安全防护全国重点实验室,北京100081 [3]北京市民航安全分析及预防工程技术研究中心,北京100028

出　　处：《爆炸与冲击》2025年第2期126-136,共11页Explosion and Shock Waves

基　　金：国家重点研发计划(2023YFC3009504);国家自然科学基金(U2033204);民航安全能力项目(xxx2146903446)。

摘　　要：为准确预测磷酸铁锂电池热失控产物的爆炸下限,在密闭压力容器内开展了磷酸铁锂电池热失控实验,结合热失控特性和气相色谱-质谱联用技术,计算了热失控产物气体组分,基于能量守恒方程和绝热火焰温度,建立了磷酸铁锂电池热失控产物爆炸下限的预测模型,并验证了绝热火焰温度法、Le Chatelier法和Jones法的准确性,考察了电解液蒸气对热失控产物爆炸下限的影响。结果表明,常温下采用Le Chatelier法计算得到的爆炸下限偏差最小,为1.14%;采用绝热火焰温度法计算结果偏差最大,为10.02%。在60%~100%荷电状态(state of charge, SOC)范围内,磷酸铁锂电池热失控气体的爆炸下限先升后降。当热失控产物考虑电解液蒸气时,60%SOC磷酸铁锂电池热失控产物爆炸下限仅为3.93%,较未考虑电解液蒸气热失控气体的爆炸下限降低了22.49%,这说明电解液蒸气提高了磷酸铁锂电池热失控产物的爆炸风险。To predict precisely the lower explosion limit of thermal runaway products of lithium iron phosphate batteries,thermal runaway tests of lithium iron phosphate batteries were carried out in a closed pressure vessel.The experiments were carried out at 25℃and 0.1 MPa,and the method was used to analyze the thermal runaway gas production.The vent gas species composition of lithium iron phosphate batteries was analyzed by gas chromatography and mass spectrometry.Combined with the thermal runaway characteristics of the battery and gas chromatography-mass spectrometry(GC-MS)technology,the gas composition of thermal runaway products of lithium iron phosphate batteries was calculated.It was assumed that the thermal runway products released from the relief valve to the first injection were all dimethyl carbonate(DMC),and the secondary injection gas was the mixed gas generated by the internal chemical reaction,which is mainly composed of H2,CO2,CO,CH4,and C2H4.A prediction model of the lower explosion limit of thermal runaway products was established based on the energy conservation equation and adiabatic flame temperature.The prediction methods of lower explosion limit of multicomponent gases based on adiabatic flame temperature,Le Chatelier law method,and Jones method were verified,and the influence of electrolyte vapor on the lower explosion limit of thermal runaway production was also investigated.The smallest deviation of the lower explosion limit calculated by the Le Chatelier law method at normal temperature and pressure was 1.14%,and the largest deviation of the lower explosion limit calculated by the adiabatic flame temperature method was 10.02%.Within the range from 60%SOC to 100%SOC,the lower explosion limit of the thermal runaway gases increases first and then decreases.When the electrolyte vapor is considered in the thermal runaway products,the lower explosion limit of thermal runaway products of lithium iron phosphate batteries with 60%SOC is only 3.93%,which is 22.49%lower than that of the thermal runaway ga

关 键 词：磷酸铁锂电池 热失控产物 爆炸下限 Le Chatelier定律 绝热火焰温度 

分 类 号：O389[理学—流体力学]