Self-Assembled LiNi1/3Co1/3Mn1/3O2 Nanosheet Cathode with High Electrochemical Performance.

We have fabricated self-assembled LiNi1/3Co1/3Mn1/3O2 nanosheets via a facile synthesis method combining coprecipitation with the hydrothermal method. Scanning electron microscopic images show that the self-assembly processes for the LiNi1/3Co1/3Mn1/3O2 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 LiNi1/3Co1/3Mn1/3O2 nanosheets have demonstrated outstanding electrochemical performance. The initial specific capacity was 193 mAh g-1, and the capacity was maintained at 189 mAh g-1 after 100 cycles at 0.2 C, and 155 mAh g-1 at 1 C (after 1000 cycles). The LiNi1/3Co1/3Mn1/3O2 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 LiNi1/3Co1/3Mn1/3O2 nanosheets for energy storage applications.