(624a) Carbon Nanomaterial Dense Layer Formation On Graphite Particles for Li-Ion Battery Anode By Using Colloidal and CVD Combined Process

Carbon nanomaterials, such as carbon nanotube, CNT and carbon nano fiber, CNF, have various high functional properties to develop Li-ion battery performance. However, hard aggregates of CNT during CVD preparation process were formed in gas phase, and such aggregates hindered to prepare uniform and high performance electrode. Such hard aggregates were not able to be dispersed by conventional physical processes. In this research, new preparation process of carbon nanomaterials uniform and dense layer on the surface of graphite fine particles, which is Li ion battery anode raw material, are developed. Uniform carbon nanomaterials coated layer on graphite will develop the performance of Li battery anode material. Firstly, surface modified CoO nanoparticles, which are precursor of Co nanoparticle catalyst for CNT formation in CVD process, were prepared in liquid phase and adsorbed on graphite particles. By the selection of optimum surface organic molecular structure on CoO nanoparticles, high coverage of CoO nanoparticles on graphite was achieved in toluene. Surface interaction control between CoO nanoparticles and graphite was useful to increase the number density of adsorbed nanoparticles on graphite. After reduction of CoO nanoparticles on graphite in gas phase, carbon nano fiber dense layers were formed on the surface of graphite particles by CVD process. Since the amount of produced carbon nano fiber on graphite was depended on the number density of adsorbed CoO nanoparticles, colloidal surface interaction design between CoO nanoparticles and graphite was important for high performance raw powder materials.