Ultrathin TiO2 Coating on LiCoO2 for Improved Electrochemical Performance as Li–Ion Battery Cathode

Abstract

AbstractSurface modification of LiCoO2 (LCO) gained much attention as it could play a prominent role in improving electrochemical performance and structural stability. Herein, we report an ultra‐thin TiO2 coating on LiCoO2 (LCO‐TiO2) as a potential candidate to overcome the electrochemical, structural instability and interface issues of the bare‐LCO. The structural properties as well as electrochemical performances of bare‐LCO and LCO‐TiO2 were investigated by X‐Ray diffraction, Transmission Electron Microscopy (TEM), X‐ray Photoelectron Spectroscopy (XPS), Galvanostatic charge‐discharge and electrochemical impedance spectroscopy (EIS). At the end of 100 cycles, 1C rate capacity retention was about 50% and 90% for bare‐LCO and LCO‐TiO2 respectively. Rate studies showed that the bare LCO exhibited a specific capacity of ∼120 mAh/g and only 16 mAh/g at 1C and 60 discharge rates respectively whereas, the TiO2 coated LCO showed a capacity of ∼132 mAh/g and nearly 98 mAh/g at 1C and 60C discharge rates respectively. The implementation of TiO2 coating over LiCoO2 enhanced the electrochemical performance, cell stability as well as efficiency.