Effect of SEI Component on Graphite Electrode Performance for Li-Ion Battery Using Ionic Liquid Electrolyte

In this study, we investigated the role of solid electrolyte interface (SEI) films in the cells fabricated with the ionic liquids ([N2,2,1(2O1)][TFSI] and [Li(G4)][TFSI]). The SEI was introduced beforehand to the graphite electrode, which facilitated the intercalation of Li-ions into the graphite electrode in [Li(G4)][TFSI]. In addition, the discharge capacity in the case of the cell fabricated with [Li(G4)][TFSI] was almost similar to that observed in the case of the cell fabricated with organic electrolyte. The SEI performed the pulling apart combination of glyme and Li-ion. Identification analysis of the SEI component having action of extracting Li-ion from [Li(G4)] was carried out.