Nanoscale Silicon-Carbon Based Composite Heterostructures: A New Paradigm in High Energy Density Li-Ion Anodes

摘要

1. The Si/C/CNTs nanocomposites were successfully synthesized by dispersing CNTs into the pre-milled Si/C powder in toluene followed by a heat treatment at temperature 1073K for 6 hours. 2. The Si/C/CNTs nanocomposites exhibit a stable capacity of ～930mAh/g with capacity retention of ～0.18% loss per cycle. 3. The Si/C/CNTs nanocomposite anode also demonstrate stable cycling up to 1C rate. 4. The excellent capacity retention of Si/C/CNTs is attributed to the formation of a nanosized conductive network matrix by CNTs to maintain contact between the Si and C particles. 5. Microstructural analyses indicate embedment of Si by graphite and good contact between the Si/C particles by the secondary CNT network resulting in good stability during cycling.