Solvate Ionic Liquid, [Li(triglyme)1][NTf2], as Electrolyte for Rechargeable Li–Air Battery: Discharge Depth and Reversibility

This study reports a reversible oxygen reduction–oxygen evolution reaction (ORR–OER) that uses a solvate ionic liquid, [Li(triglyme)1][NTf2], as an electrolyte for a rechargeable Li–air (O2) battery. Significantly, it was found that the reversibility and capacity retention for ORR–OER in the solvate ionic liquid was greatly improved with a decrease in the ORR discharge depth; the discharge to 2.2 V vs. Li/Li+ gave much better reversibility than that to 2.0 V vs. Li/Li+.