A Li/CO2–O2 (2:1, volume ratio) battery and a Li/CO2 battery with discharging specific capacities of 1808 mA h g−1 and 1032 mA h g−1, respectively, are reported. Li2CO3 is the main discharge product in the Li/CO2–O2 (2:1) battery and can be decomposed during charging. In the Li/CO2 battery, the main discharge products could be Li2CO3 and carbon. Both batteries can be cycled reversibly at room temperature.
