Abstract
A lithium-rich layered cathode material [0.4Li2MnO3·0.6Li(Mn0.43Ni0.36Co0.21)O2)] containing nanosized grains (50–100 nm) was prepared from an aqueous precursor solution via a sequential two-step process composed of ultrasonic spray pyrolysis and post-calcination. The microsized lithium-rich layered composites show a high initial discharge capacity of 251 mA h g−1 at 0.1 C. The reversible capacities of 206 mA h g−1 at 0.5 C and 189 mA h g−1 at 1 C are obtained between 4.6 and 2.0 V. These are comparable to the values reported previously for these materials, without the need for doping or surface modification. The improved electrochemical performance may have resulted from the presence of nanosized grains, which can lead to an improvement in electronic and ionic transport, and the homogeneously dispersed Li2MnO3 phase in the LiMO2 (M = Mn, Ni, Co) phase. These results suggest that spray pyrolysis is an effective technique for the preparation of multi-component composite materials and can be used to control the microstructure of the materials, ultimately improving the electrical performance.
