Electrochemical Insertion of Magnesium in Metal Oxides and Sulfides from Aprotic Electrolytes

The electrochemistry of , , , , and has been studied in several organic solvents containing in view of their application as positive electrodes in rechargeable magnesium batteries. Only showed promising coulombic capacity and reversibility. Mg2+ insertion into this oxide depends on the ratio between the amounts of and Mg2+ as well as on the absolute amount of in the electrolyte. Water molecules preferentially solvating Mg2+ions appear to facilitate the insertion process. The highest coulombic capacities of up to 170 Ah/kg were reached in acetonitrile solutions containing .