Analysis on explosion-proof techniques and standards for lithium-ion battery power supply used in underground coal mine

The essential properties of high energy density,stability and long cycle life of lithium ion batteries rendered its widespread applications in mining occupations.However,the use of lithium-ion battery power supply in underground coal mines with explosive gas atmosphere poses unique explosion hazards considering its high-energy chemical properties and potential thermal runaway risk.These risks required urgent attention and comprehensive protection techniques to mitigate the potential of any catastrophic events such as fires and explosions.Based on the techniques published in the IEC 60079 standards,GB 3836 standards and relevant handbooks,this article introduced the explosion protection techniques currently applicable to electrical equipment used in underground coal mines and the equipment protection levels corresponding to different explosion protection techniques with emphasize on special protection technique and EPL Ma protection level.The causes of thermal runaway of lithium-ion batteries and the associated catastrophic hazards were analyzed inclusive the battery management technology and explosion-proof protection techniques.The article also presented the systematic risk assessment practices that to ensure the integrity of battery management system for lithium-ion battery power pack that used in underground coal mines where arduous and hazardous environment prevails.The method to determine the safety integrity level of the adopted battery management system are also explained.As there is currently no specific standard or requirements for large-capacity lithium-ion battery power supplies used in underground coal mines across the world,this article suggested three importance areas that worth noted to improve the safety level of the lithium-ion battery power supply.It also path the way for the potential establishment of relevant industry and national standards based on the special protection method provided in IEC 60079 and GB 3836 and the discussed risk assessment techniques.