Enhancement of the electrochemical properties of LiMn2O4 through chemical substitution

The electrochemical performance of spinel-type LiMn2O4 cathode active materials has been effectively improved by dual doping with chromium and fluorine. The influence of different doping element on the structural and electrochemical properties of as-prepared samples was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and charge/discharge measurements. The results indicated that fluorine play an important role in controlling morphology, and the doped chromium could enhance significantly the stability of spinel-type LiMn2O4. The LiCr0.1Mn1.9O4 powders show high capacity retention, which is 95.4% of the initial after 30 cycles, and the novel compound LiCr0.1Mn1.9O3.95F0.05 with regular cubic spinel shapes was found to offer much higher capacity, whose initial discharge capacity was 130.6 mAh g−1.