Silicon Embedded Nanoporous Carbon Composite for the Anode of Li Ion Batteries

Silicon-embedded nanoporous carbon composites were designed and fabricated for application as an active anode material in lithium ion batteries. The nanoporous carbon matrix with pore sizes of 80-100 nm was prepared using silica nanoparticle templates, and the pores of the carbon matrix were partially filled with silicon nanostructures using metal-catalyzed vapor-liquid-solid (VLS) growth of silicon. The porous carbon matrix surrounding the silicon nanomaterials acts as an effective buffer material, which decreases pulverization of the silicon. In addition, the interconnected porous structure and tight contact between the Si nanostructure and the surrounding carbon enable facile electron and ion transport to generate an efficient charge/discharge pathway. The composite materials used as the anode in lithium ion batteries demonstrated a high charge storage capacity of similar to 1,600 mAh g(-1), which is similar to 96% of the calculated maximum capacity at the composition, and good capacity retention characteristics. (C) 2012 The Electrochemical Society. [DOI: 10.1149/2.070208jes] All rights reserved.