Mesoporous carbon-encapsulated NiO nanocomposite negative electrode materials for high-rate Li-ion battery

In this study, a novel mesoporous carbon-encapsulated NiO nanocomposite is proposed and demonstrated for Li-ion battery negative electrode. The nanostructure of the electrode composes of an ordered mesoporous CMK-3 as a 3D nanostructured current collector with micorporous channels for Li+ transportation. In addition, exclusive formation of NiO nanoparticles in the confined space of the ordered mesoporous carbon is achieved using the hydrophobic encapsulation route. The half-cell assembled with the synthesized NiO/CMK-3 nanocomposite is able to deliver a high charge capacity of 812 mAh g(-1) at the first cycle at a C-rate of 1000 m Ag-1 and retained throughout the test with only 0.236% decay per cycle. Even the C-rate as high as 3200 mA g(-1), a charge capacity of 808 mAh g(-1) contributed by the NiO nanoparticles in CMK-Ni is obtained, which shows excellent rate capability for NiO with utilization close to 100%. The result suggests fast kinetics of conversion reaction for NiO with Li+. It also indicates the blockage of the pore channels by NiO nanoparticles does not take place in the synthesized NiO/CMK-3. (C) 2010 Elsevier B.V. All rights reserved.