Spherical LiCoO2 particles embedded with carbon nanotubes have been prepared via self-assembly in water/oil microemulsion. Mesoporous spherical LiCoO2 was obtained by burning out the carbon nanotubes at 300 degrees C in an O-2 atmosphere. The structure and morphology of the mesoporous particle were characterized with X-ray diffraction, scanning electron microscope, and Brunauer, Emmett, and Teller method. It revealed that the mesoporous particles are comprised of submicrometer-sized LiCoO2 grains, possessing high specific surface area up to 36 m(2)/g and with an average mesopore diameter of similar to 22.5 nm. The synthesized spherical LiCoO2 shows improved reversibility and cyclability at high rate 5 C. (c) 2008 The Electrochemical Society.