Synthesis and electrochemical characterization of Li1.05RExCryMn2−x−yO4 spinel as cathode material for rechargeable Li-battery

The spinel phases of Li1.05RExCryMn2−x−yO4 (RE = Sc, Ce, Pr, Tb; 0 ≤ x ≤ 0.05; 0 ≤ y ≤ 0.1) were prepared by a soft chemical method. The structural and electrochemical properties of Li1.05RExCryMn2−x−yO4 were investigated by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and charge–discharge experiments. Rare earth element-Sc and transition metal-Cr as co-substituents stabilize the spinel framework and improve charge–discharge performance. For Li1.05Sc0.01Cr0.03Mn1.96O4, the capacity of the cell maintained 95% of the initial capacity at the 80th cycle. The rare earth elements of the variable valent metals such as Ce3+/4+, Pr3+/4+, Tb3+/4+ with transition metal Cr3+ as co-substituent do not stable framework of spinel or improve the cycling performance. Cyclic voltammetry (CV) were measured to provide clues for the improved cycling performance of cathode electrodes.