Rechargeable Li-Air Batteries with Carbonate-Based Liquid Electrolytes

Rechargeable Li-air battery is a candidate for post Li-ion battery with high energy density. In this paper, the rechargeability of Li-air battery over 100 cycles was confirmed and its capacity retention over 60% was achieved. Nevertheless, a large voltage gap between the discharge-charge profiles was observed. Here, a discharged product formed on a cathode was investigated by TEM observation and FT-IR spectroscopy. It was found that the main product formed in discharge was not an ideal compound, Li2O2, but was carbonate species issued from the decomposition of carbonate-based electrolyte solvent.