Mechanistic insights for the development of Li-O-2 battery materials: addressing Li2O2 conductivity limitations and electrolyte and cathode instabilities

The Li-air battery has received significant attention over the past decade given its high theoretical specific energy compared to competing energy storage technologies. Yet, numerous scientific challenges remain unsolved in the pursuit of attaining a battery with modest Coulombic efficiency and high capacity. In this Feature Article, we provide our current perspective on challenges facing the development of nonaqueous Li-O-2 battery cathodes. We initially present a review on our understanding of electrochemical processes occurring at the nonaqueous Li-O-2 cathode. Electrolyte and cathode instabilities and Li2O2 conductivity limitations are then discussed, and suggestions for future materials research development to alleviate these issues are provided.