Cycling Na-O2 batteries via Li2O2 formation and Na deposition

In Na-O2 batteries, the active discharge product NaO2 always undergoes a disproportionation reaction and induces electrolyte decomposition, causing byproducts accumulation and cell polarization. Here, a new hybrid Na/Li+/O2 battery is constructed by controlling the formation of exclusive discharge products Li2O2 combined with the abundance resources of Na anode. It enables the sole discharge product Li2O2 formation at the cathode after discharge, thus reducing the side reaction. Upon charge, it only guarantees Na deposition, no Li deposition accompanied by no dendrite formation. Also, the easier desolvation effect of Li+ than Na+ and the electrostatic shielding of Li+ are the keys to improving the electrochemical performance of Na-O2 batteries.