Crystal structure study of LiNi1−xMnxO2

Manganese in an LiNi1−xMnxO2 mixed valence compound, provided a layered structure of LiNiO2 (image) substituting a part of the 3a site to manganese was found to exist in part of the nickel site by using XAFS measurement and Rietveld analysis, and the majority of manganese existed in a divalent state by using electron spin resonance measurement. This material has less overvoltage than LiNiO2 at the end of charging state. It is presumed that control of the mixed valence affects the electron occupation state of the valence band, mainly eg orbit, and the crystal field, providing an action/relaxing change of the electron occupation state of the valence band according to the charge/discharge reaction.