Electrochemical properties of coated spinel LiMn_2O_4

LiCoxMn2-xO4 - coated spinel LiMn2O4 was prepared by soft chemistry process, then the LiCoxMn2-xO4 - coated spinel LiMn2O4 and the uncoated spinel LiMn2O4 were characterized by methods of cyclic voltammetry, constant current charge - discharge and potential decay. Ther results showed that the initial capacity of LiCoxMn2-xO4 -coated spinel LiMn2O4 was lower than that of uncoated spinel LiMn2O4 After 50 cycles, the capacity loss of uncoated spinel LiMn2O4 was 56. 2% of initial, while that of LiCoxMn2-xO4 -coated spinel LiMn2O4 was 33. 5%, and LiCoxMn2-xO4 - coated spinel LiMn2O4 had better chemical stability than uncoated spinel LiMn2O4. Better cyclic stability of LiCoxMn2-xO4- coated spinel LiMn2O4 may be attributed to the surface layer LiCoxMn2-xO4, which reduces the LiMn2O4 dissolution into electrolyte.