Suppression of O2 evolution from oxide cathode for lithium-ion batteries: VO(x)-impregnated 0.5Li2MnO3-0.5LiNi(0.4)Co(0.2)Mn(0.4)O2 cathode.

A VO(x)-impregnated oxide cathode for lithium ion batteries exhibits a substantial drop in oxygen evolution during high voltage operation. An electrolyte was found to catalyze the gas evolution, and the VO(x) layer could protect the cathode oxide surface from the electrolyte and stabilize the surface oxide ions during their electrochemical oxidation.