Understanding oxygen electrochemistry in aprotic LiO2 batteries

Abstract In the past decade, the aprotic lithium–oxygen (Li O 2 ) battery has generated a great deal of interest because theoretically it can store more energy than today's lithium-ion batteries. Although considerable research efforts have been devoted to the R&D of this potentially disruptive technology, many scientific and engineering obstacles still remain to be addressed before a practical device could be realized. In this review, we summarize recent advances in the fundamental understanding of the O 2 electrochemistry in Li O 2 batteries, including the O 2 reduction to Li 2 O 2 on discharge and the reverse Li 2 O 2 oxidation on recharge and factors that exert strong influences on the redox of O 2 /Li 2 O 2 . In addition, challenges and perspectives are also provided for the future study of Li O 2 batteries.