矿用防爆锂离子电池电源安全设计影响因素研究

Study on influencing factors of mine explosion-proof lithium-ion battery power supply safety design

锂离子电池潜在的热失控风险及其可能引发的叠加效应对大型锂离子电池电源的安全设计提出了巨大挑战,因此在某些特殊应用领域,如煤矿井下爆炸性环境,大容量锂离子电池电源的使用依然存在诸多限制,难以普及。根据现有针对锂离子电池热失控行为的研究结论,在不进行充分的气体热力学和动力学分析的前提下,仅采用传统隔爆外壳对大容量锂离子电池电源进行防爆保护,存在隔爆外壳内部压力积聚的安全隐患。在分析现有研究工作的基础上,选用不同电池制造商生产的容量在72~280 A·h范围内的磷酸铁锂电池进行了热失控试验研究,全面分析了锂离子电池热失控过程中电池表面以及释放气体的温度、气体释放速度、释放气体在容器内产生的压力和释放气体的成分等相关参数。在此基础上,根据气体动力学和热力学特性,系统阐述了适用于煤矿井下爆炸性环境用可移动设备和后备电源等设备的锂离子电池电源在设计和制造过程中需要重点考虑的2个因素:①锂离子电池电源外壳内部的自由空间,②锂离子电池电源内部单体电池发生热失控事故时针对所释放气体的处理方法,并提出了必要的设计依据。本研究成果有望对爆炸性特殊环境用锂离子电池电源的防爆保护设计和安全完整性评估提供新的重要参考依据。

The potential thermal runaway risk of lithium-ion batteries and the superimposing effects they may cause pose a huge challenge to the safety design of large-scale lithium-ion battery power supplies.Therefore,in some special applications,such as explosive environments in coal mines and large-capacity lithium-ion batteries,there are still many restrictions on the use of power sources and it is difficult to popularize.According to the existing research conclusions on the thermal runaway behavior of lithium-ion batteries,under the premise of insufficient gas thermodynamics and kinetic analysis,only the traditional explosion-proof enclosure is used to protect the power supply of large-capacity lithium-ion batteries for explosion-proof.There is a potential safety hazard for the lithium battery to discharge the explosion-proof enclosure pressure.Based on the analysis of existing research work,this paper selects lithium iron phosphate batteries produced by different battery manufacturers with a capacity in the range of 72~280 A·h to conduct thermal runaway experimental research,a comprehensive analysis of the battery surface and the temperature of the released gas during the thermal runaway process of the lithium-ion battery,the gas release rate,the pressure of the released gas in the container,and the composition of the released gas are comprehensively analyzed.On this basis,according to the characteristics of gas dynamics and thermodynamics,the two factors that need to be considered in the design and manufacture of lithium-ion battery power supplies suitable for portable equipment and backup power supplies for explosive environments in coal mines are systematically explained:①The free space inside the casing of the lithium ion battery power supply,②The treatment method for the released gas when a thermal runaway accident occurs in the internal single battery of the lithium ion battery power supply,and the necessary design basis is proposed.The results of this research are expected to provide a new important reference for the explosion protection design and safety integrity assessment of lithium-ion battery power supplies used in explosive special environments.