The Role of Charge Reactions in Cyclability of Lithium–Oxygen Batteries

The significant influence of product removal upon charge on cyclability of Li–O2 batteries with carbon electrodes is demonstrated. Optimal charge cut-off voltages lead to 32 cycles for the tetraethylene glycol dimethyl ether (TEGDME)-based batteries, and 40 cycles for the N-methyl-N-propylpiperidinium bis(trifluoromethansulfony) imide (PP13TFSI)-based ones without degradation of the retained discharge capacity. Further extension of cycle operation would need introduction of catalysts that can avoid by-product accumulation.