A rechargeable Mg vertical bar O-2 battery

Rechargeable Mg vertical bar O-2 batteries (RMOBs) offer several advantages over alkali metal-based battery systems owing tt, Mg's ease of transport/storage in ambient environment, low cost originatin )m its high abundance, as well as the high theoretical specific energy of RMOBs. However, research on RMOBs has been stagnant for the past decade, largely owing to unacceptably poor electrochemical performance. Here, we present a RWOB that employs Mg anode, Mg((CF3SO2)(2)N)(2)-MgCl2 in diglyme (G2) electrolyte, and commercial Pt/C on carbon fiber paper (Pt/C@CFP) oxygen Lathode. This battery demonstrates unparalleled improvement over existing RMOBs by rendering a discharge capacity over 1.6 mAh cm(-2), achieving cycle lives up to 35 cycles with a cumulative energy density of similar to 3.2 mWh cm(-2) at room temperature. This RMOB system seeks to reignite the pursuit of novel electrochemical systems based on Mg-O-2 chemistries.