Requirements for reversible extra-capacity in Li-rich layered oxides for Li-ion batteries

Abstract

Oxygen lone-pairs (|O) are responsible for the extra-capacity observed in Li-rich Li₂MO₃ electrodes and not in LiMO₂. M–O covalency is required to stabilize the oxidized O⁻ species involved in the anionic process and to prevent O₂ release.