Safety issues have been attracted more and more attentions due to the wide applications of lithium ion batteries.Introducing flame retardant additives are one of the effective strategies to improve the safety of lithium-ion batteries. In this paper,tetrabutylammonium hexafluorophosphate(TBAPF_6) as a flame retardant additive was added to the electrolyte to enhance the safety of lithium ion batteries. The self-extinguishing time(SET) and ionic conductivities of electrolytes with different TBAPF_6 contents we...