THE EFFECTS OF CARBON NANO-COATING ON Li(Ni0.8Co0.15Al0.05)O2 CATHODE MATERIAL USING ORGANIC CARBON FOR Li-ION BATTERY

摘要

Carbon nano-coated LiNi0.8Co0.15Al0.05O2/C (LNCAO/C) cathode-active materials were prepared by a sol–gel method and investigated as the cathode material for lithium ion batteries. Electrochemical properties including the galvanostatic charge–discharge ability and cyclic voltammogram behavior were measured. Cyclic voltammetry (2.7–4.8 V) showed that the carbon nano-coating improved the “formation” of the LNCAO electrode, which was related to the increased electronic conductivity between the primary particles. The carbon nano-coated LNCAO/C exhibited good electrochemical performance at high C-rate. Also, the thermal stability at a highly oxidized state of the carbon nano-coated LNCAO was remarkably enhanced. The carbon nano-coating layer can serve as a physical and/or (electro-)chemical protection shell for the underlying LNCAO, which is attributed to an increase of the gr ain connectivity (physical part) and also to the protection of metal oxide from chemical reactions (chemical part).