A rechargeable molten salt electrolyte battery has an anode comprising lithium, a cathode electrode comprising a conductive metal that is compatible with the nitrate melt, an electrolyte comprising lithium nitrate or lithium nitrate mixtures with other nitrates which electrolyte is capable of becoming an ionic conductive liquid upon being heated above its melting point, wherein oxygen for reaction at the cathode or within the melt is provided from an external source to be delivered to the cathode through the electrolyte and provision is made to collect lithium oxide formed during discharge to be reconstituted as lithium ions and oxygen during recharge. At least a portion of the oxygen reduction reaction is provided by a nitrate ion pathway.