INORGANIC MATERIALS, cilt.44, ss.420-425, 2008 (SCI İndekslerine Giren Dergi)
—In order to improve the cycling performance of LiMn2O4, the spinel phases LiCo0.15Mn1.85O4 and LiCo0.05M0.1Mn1.85O4 (M = Ni, Zn, Cu) were prepared by the sol–gel method. Their structures have been investigated by x-ray diffraction. Electrochemical studies were carried out using the LixMn2O4(x= 1.05, 1.1),LiCo0.15Mn1.85O4, and LiCo0.05M0.1Mn1.85O4 (M = Ni, Zn, Cu) cells. The capacity loss of Li|LixMn2O4 (x=1.05, 1.1)cells is about 21.7 and 6.4% after 30 cycles, whereas that for Co, Co–Ni, Co–Zn, and Co–Cu doped spinel materials is about 4.0, 2.0, 1.0, and 1.9%, respectively. The good capacity retention of LiCo0.05 M0.1Mn1.85O4 (M = Ni, Zn, Cu) electrodes is attributed to stabilization of spinel structure by double metal doping for Mn ion sites. Double substituted spinels display better performance in terms of cycle-life compared with LiMn2O4.