Imidazolium Based Ionic Liquid Electrolytes for Li-Ion Secondary Batteries Based on Graphite and LiFePO 4

This manuscript reports the development of a safe and green lithium-ion battery using lithium iron phosphate (LiFePO 4 ) as a positive electrode, graphite (Cgr) as a negative electrode, and an Ionic Liquid (IL) electrolyte solution based on 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)-imide (C 1 C 6 ImNTf 2 ). Vinylene carbonate (VC) was tested as an electrolyte additive. The electrochemical stability of (C 1 C 6 ImNTf 2 ) and their binary mixture referred as (Li)(C 1 C 6 ImNTf 2 ) were investigated. In addition the electrochemical behavior of the graphite electrode was studied through cyclic voltammetry experiments in the presence and absence of VC co- additive. Complementary cycling tests demonstrated the benefic effect of VC on the charge-discharge performances for the full Lithium ion configuration based on Cgr/LiFePO 4 .