Porous graphite/silicon micro-sphere prepared by in-situ carbothermal reduction and spray drying for lithium ion batteries

Abstract

Porous graphite/silicon micro-sphere is prepared by carbothermal reduction and spray drying method. X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) are used to evaluate the phases, morphology and microstructure of the composite. Compared with the commercial graphite anode, the as-prepared composites with different silicon contents can exhibit reversible capacity between 426.5 and 755.5 mAh/g without dramatic capacity fading. The superior electrochemical performance is attributed to integrity of electrode material, improved adhesive strength between silicon and graphite, and porous structure composed of graphite flakes with different orientations. © 2012 The Electrochemical Society. All rights reserved.