Origin of additional capacities in metal oxide lithium-ion battery electrodes

Metal fluorides/oxides are promising electrodes for lithium-ion batteries, but the mechanism by which they exhibit additional reversible capacity is still not well understood. By using high-resolution solid-state NMR techniques it is shown that extra capacity in this RuO2 system is due to the generation of LiOH and its subsequent reversible reaction with Li to form Li2O and LiH.