Cycling behaviour of barium doped LiMn2O4 cathode materials for Li ion secondary batteries

In order to improve the cycling performance of LiMn2O4, the spinel phase LiMn2–xBaxO4 (x = 0.01, 0.02 and 0.05) compounds were fabricated by the glycine-nitrate method. The structures of the products were investigated by X-ray diffraction. Electrochemical studies were carried out using the Li|LiMn2O4 and Li|LiMn2–xBaxO4 cells. The capacity loss of Li|LiMn2O4 cell is about 15% after 30 cycles, whereas that for Ba doped spinel materials (x = 0.01, 0.02 and 0.05) are 7.5%, 3.5% and 1.8% respectively. The good capacity retention of LiMn2–xBaxO4 electrodes is attributed to stabilization of the spinel structure by Ba doping of Mn sites. Ba substituted spinels display better cycle performance in terms of cycle life compared with LiMn2O4.