Self-Assembled LiNiCoMnO Nanosheet Cathode with High Electrochemical Performance.

We have fabricated self-assembled LiNiCoMnO nanosheets via a facile synthesis method combining coprecipitation with the hydrothermal method. Scanning electron microscopic images show that the self-assembly processes for the LiNiCoMnO nanosheets depend on the reaction time and temperature. The nanosheet structure is uniform, and the width and thickness of the nanosheets are in the ranges of 0.7-1.5 μm and 10-100 nm, respectively. As a cathode material, the as-synthesized LiNiCoMnO nanosheets have demonstrated outstanding electrochemical performance. The initial specific capacity was 193 mAh g, and the capacity was maintained at 189 mAh g after 100 cycles at 0.2 C, and 155 mAh g at 1 C (after 1000 cycles). The LiNiCoMnO nanosheets have efficient contact with the electrolyte and short Li diffusion paths, as well as sufficient void spaces to accommodate large volume variation. The nanosheets are thus beneficial to the diffusion of Li in the electrode. The enhanced electrical conductance and excellent capacity demonstrate the great potential of LiNiCoMnO nanosheets for energy storage applications.