Fabrication and electrochemical performance of 0.6Li(2)MnO(3)-0.4Li(Ni(1/3)Co(1/3)Mn(1/3))O(2) microspheres by two-step spray-drying process

0.6Li(2)MnO(3)–0.4Li(Ni(1/3)Co(1/3)Mn(1/3))O(2) composite microspheres with dense structures are prepared by a two-step spray-drying process. Precursor powders with hollow and porous structures prepared by the spray-drying process are post-treated at a low temperature of 400°C and then wet-milled to obtain a slurry with high stability. The slurry of the mixture of metal oxides is spray-dried to prepare precursor aggregate powders several microns in size. Post-treatment of these powders at high temperatures (>700°C) produces 0.6Li(2)MnO(3)–0.4Li(Ni(1/3)Co(1/3)Mn(1/3))O(2) composite microspheres with dense structures and high crystallinity. The mean size and geometric standard deviation of the composite microspheres post-treated at 900°C are 4 μm and 1.38, respectively. Further, the initial charge capacities of the aggregated microspheres post-treated at 700, 800, 900, and 1000°C are 336, 349, 383, and 128 mA h g(−1), respectively, and the corresponding discharge capacities are 286, 280, 302, and 77 mA h g(−1), respectively. The discharge capacity of the composite microspheres post-treated at an optimum temperature of 900°C after 100 cycles is 242 mA h g(−1), and the corresponding capacity retention is 80%.