LiNi0.1Mn0.1Co0.8O2 electrode material: Structural changes upon lithium electrochemical extraction

We reported here on the synthesis, the crystal structure and the study of the structural changes during the electrochemical cycling of layered LiNi0.1Mn0.1Co0.8O2 positive electrode material. Rietveld refinement analysis shows that this material exhibits almost an ideal alpha-NaFeO2 structure with practically no lithium-nickel disorder. The SQUID measurements confirm this structural result and evidenced that this material consists of Ni2+, Mn4+ and Co3+ ions. Unlike LiNiO2 and LiCoO2 conventional electrode materials, there was no structural modification upon lithium removal in the whole 0.42 <= x <= 1.0 studied composition range. The peaks revealed in the incremental capacity curve were attributed to the successive oxidation of Ni2+, and Co3+ while Mn4+ remains electrochemically inactive. (C) 2010 Elsevier Ltd. All rights reserved.