HIGH-PERFORMANCE LICOO2 POSITIVE ELECTRODE MATERIAL

LiMO(2) (M=Co, Ni) and LiMn2O4 compounds synthesized at low temperature (LT) show very different electrochemical properties compared with their high-temperature (HT) analogues: These powders are in general characterized by a higher surface area and smaller grain size. When used as cathode materials in lithium secondary batteries, such LT compounds should show an enhanced electrochemical behaviour under heavy drain. We have developed a new synthesis method of LiMO(2) and LiMn2O4 characterized by monodispersive grain size powders, high surface area, good crystallinity, and a chemical composition close to the stoichiometry. We have carried out a comparison of the electrochemical properties of LiCoO2 powders obtained by the classical method and this new synthesis route. In spite of a slightly lower discharge capacity, the new powder showed higher performances in terms of rate capacity.