Synthesis and characterisation of electrode materials for sodium ion battery

Abstract

The interest in Sodium Ion Batteries have grown in recent years, in the light of the lithium depletion that has been used widely in our everyday lives. To compare the effect of cobalt doping and morphology as improvement strategies for metal oxide cathodes, five representatives of the P2-layered Na0.6MO2 (M = transition metal) have been studied, namely Na0.6MnO2 flake and sphere, as well as P2-Na0.6¬Mn0.9Co0.1O2, P2-Na0.6-Mn0.8Co0.2O2 and P2-Na0.6¬Mn0.6Co0.4O2. The higher capacity of the spheres over the flakes are explained based on the structural features observed using the Scanning Electron Microscope. Additionally, improved cycling stability of Co-doped materials is attributed to better accommodations to volume changes due to its spherical morphology. The two approaches in optimisation of morphology and doping have been shown to be successful in attaining higher capacity and cycling stability.