Evaluation of Mg[N(SO₂CF₃)₂]₂/Acetonitrile Electrolyte for Use in Mg-Ion Cells

Mg[N(SO 2 CF 3 ) 2 ] 2 /Acetonitrile electrolyte was evaluated for use in Mg-ion cells. It was found to have a stable potential range between about −0.2 V and 2.8 V vs. Mg against a stainless steel working electrode. Higher voltages resulted in stainless steel corrosion, while lower voltages resulted in acetonitrile reduction. No Mg plating was observed. Reversible intercalation of Mg into Mo 6 S 8 was demonstrated in this electrolyte with significantly lower irreversible capacity, compared to cycling in Grignard-based electrolytes. Mg[N(SO 2 CF 3 ) 2 ] 2 /Acetonitrile electrolyte may be useful for Mg-ion batteries, if the negative electrode has sufficiently high voltage to avoid acetonitrile reduction.