Polyaspartic-acid-pyrolysis route for the synthesis of nanocrystalline LiCo0.15Mn1.85O4 powder for Li-ion batteries

摘要

Nanocrystalline cubic spinel LiCo0.15Mn1.85O4 powder was prepared by a novel method based on in situ polymerization of aspartic acid along with metal salts. Thermal study shows that the complete crystallization and/or formation of the compound is at 358 °C. The structural property of the synthesized material was characterized by X-ray diffraction studies. The X-ray diffractogram reveals the single-phase formation of the product. Scanning electron microscope study shows that the average grain size of the powder is less than 1 μm. To assess the electrochemical performance of the synthesized cathode material, the C/LiCo0.15Mn1.85O4 cell with 1 M LiPF6 in 1:1 (v/v) mixture of ethylene carbonate and dimethyl carbonate as the electrolyte was assembled, and the charge and discharge studies were made in between 3.0 and 4.8 V at a constant current density of 0.1 mAcm?2. It shows that capacity loss is only 2% even after the 50th cycle. As this preparation method is simple and particularly suitable for preparation of highly homogeneous mixed metal oxides for Li-ion batteries.