Onion-like carbon matrix supported Co3O4 nanocomposites: a highly reversible anode material for lithium ion batteries with excellent cycling stability

Co3O4/onion-like carbon (OLC) nanocomposites with a high surface area of 222.83 m(2) g(-1) were synthesized by a simple solvothermal method for application as an anode material in lithium ion batteries (LIBs). The electrochemical properties of the hybrid nanocomposites were investigated by a half-cell LIB configuration with lithium foil as the counter electrode. The result shows improved battery performance including enhanced specific capacity (i.e., similar to 632 mA h g(-1) at the 100th cycle with a current density of 200 mA g(-1)) and excellent cycling stability, which are attributed to good conductivity and fast ion transportation of the nanocomposites. Remarkably, this new anode material also exhibited an extremely high rate capability at various current densities from 50 to 2000 mA g(-1). These results suggest that such a Co3O4/OLC hybrid composite architecture is promising for next generation high capacity and safe LIBs.