Oxygen stability study of Li-rich compound: First Principle Analysis

High energy density Li-rich layered cathode materials suffer from structural instability at high voltage. It is known that oxygen stability influence the structural stability of Li2MO3 (M=Co/Mn/Ni). Oxygen stability with partial de-lithiation has not been clarified in presence of multiple d-orbital elements. This work presents density functional theory based study of Li1.17Ni0.17Mn0.67O2. In the series of Li-rich compounds, end point material is Li2MnO3, in which oxidation of Mn4+ compensates with oxidation of O2- to O2 while charging. This makes Li2MnO3 electrochemically inactive poor cathode material. Li2MnO3 become electro-chemically active when it is stabilized with LiMO2.