Composites of porous Co3O4 grown on Li2MnO3 microspheres as cathode materials for lithium ion batteries

Abstract

The core–shell structure of Co₃O₄@Li₂MnO₃ was prepared by a facile hydrothermal method following heat treatment at 300 °C. The outer shell is porous and makes the diffusion of Li⁺ ions to the inner shell easier. The synergetic effect between the core and shell shows that the Co₃O₄ shell in the composite serves as a host to react with lithium oxide removed from the Li₂MnO₃ core during the initial charging process, which eliminates the huge irreversible capacity loss of Li₂MnO₃. As the cathode material for lithium ion batteries, the composite exhibits an attractive discharge capacity of 178 mA h g⁻¹ with little irreversible capacity loss in the voltage range of 2.0–4.8 V. Its cycling performance is stable without any drastic capacity fading when cycling in the high voltage range of 2.0–4.6 V.