Enhanced high-temperature cycling stability of LiNi1/3Co1/3Mn1/3O2-coated LiMn2O4 as cathode material for lithium ion batteries

To enhance the electrochemical performances of LiMn2O4 at elevated temperature, we proposed a sol–gel method to synthesize LiNi1/3Co1/3Mn1/3O2-modified LiMn2O4. The physical and electrochemical performances of pristine and LiNi1/3Co1/3Mn1/3O4-coated LiMn2O4 cathode materials were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical measurements, respectively. The results indicated that about 5–6-nm-thick layer of LiNi1/3Co1/3Mn1/3O2 formed on the surface of the LiMn2O4 powders. The modified LiMn2O4 exhibited excellent storage performance at 45, 55, and 65 °C compared to the pristine one, which was attributed to the suppression of electrolyte decomposition and the reduction of Mn dissolution.