Novel Antimony/Aluminum/Carbon Nanocomposite for High-Performance Rechargeable Lithium Batteries

A simple method of transforming micrometer-sized Al and Sb powders into a new nanocomposite modified with carbon by the alloying reaction of Al and Sb to form the AlSb phase and the dealloying reaction of the AlSb phase with carbon to synthesize the Sb/Al 4 C 3 /C nanocomposite was developed using a high-energy mechanical milling technique. The Sb/Al 4 C 3 /C nanocomposite was confirmed, using various analytical techniques, to be composed of a reduced crystalline Sb phase, amorphous Al 4 C 3 phase, and amorphous carbon. This novel nanocomposite showed a highly reversible reaction with Li, a high capacity of 687 mAh g −1 with a good Coulombic efficiency of 85% for the first cycle, and a high capacity retention above 520 mAh g −1 over 200 cycles. Additionally, by controlling the voltage window, an excellent cyclability with a high rate capability also was achieved. These excellent electrochemical properties demonstrated by the Sb/Al 4 C 3 /C nanocomposite electrode confirm its potential as a new alternative anode material for Li-ion batteries.