Hollow carbon cage with nanocapsules of graphitic shell/nickel core as an anode material for high rate lithium ion batteries

Hollow carbon cages (HCCs) with high electrical conductivity were developed by a spray drying-catalytic graphitization-activation process as anode materials for high power lithium ion batteries. The HCC anode has a high reversible capacity of 1135 mA h g(-1) at 50 mA g(-1), excellent cyclic stability without capacity degradation over 100 cycles at a current density of 500 mA g(-1), and an ultrafast charge/discharge rate of less than 2 min with a high capacity of 163 mA h g(-1), which are attributed to the unique structure of the hollow cores, the high porosity, and electrically conductive nickel nanoparticles and the graphitic layers produced by the carbothermal reduction of nickel hydroxide and the low-temperature catalytic graphitization.