Fine-sized LiNi0.8Co0.15Mn0.05O2 cathode powders prepared by combined process of gas-phase reaction and solid-state reaction methods

The Ni-rich precursor powders with spherical shape and filled morphologies were prepared by spray pyrolysis from the spray solution with citric acid, ethylene glycol and a drying control chemical additive. The precursor powders with controlled morphologies formed the LiNi0.8Co0.15Mn0.05O2 cathode powders with spherical shape and fine size by solid-state reaction with lithium hydroxide. However, the cathode powders prepared from the spray solution without additives had irregular morphologies and were large in size. The precursor powders with hollow and porous morphologies formed cathode powders with irregular and aggregated morphologies. The composition ratios of the nickel, cobalt and manganese components were maintained in the as-prepared, precursor and cathode powders. The initial discharge capacity of the LiNi0.8Co0.15Mn0.05O2 cathode powders with spherical shape and fine size tested at a temperature of 55 degrees C under a constant current density of 0.5 C was 215 mAh g(-1). The discharge capacity of the LiNi0.8Co0.15Mn0.05O2 cathode powders decreased to 81% of the initial value after 30 cycles. (C) 2007 Elsevier B.V. All rights reserved.