We demonstrate a new rechargeable zinc-air battery with a molten carbonate electrolyte. CV reveals reversible deposition/dissolution of zinc from the molten carbonate electrolyte. At 550 °C, this Zn-air battery performs with a 97% coulombic efficiency over 110 cycles. The battery exhibits a charging potential of ∼1.43 V and discharge potential of ∼1.04 V. The zinc-air battery uses a cost effective steel electrode and a nickel air electrode.