Preparation of Sn{sub}2Sb alloy encapsulated carbon microsphere anode materials for Li-ion batteries by carbothermal reduction of the oxides

摘要

A novel process was proposed to prepare Sn{sub}2Sb-encapsulated carbon microspheres (CM/Sn{sub}2Sb) anode materials by inverse emulsion polymerization of resorcinol-formaldehyde (RF) performed in the presence of Sb{sub}2O{sub}3 and SnO{sub}2 powders (1/4 molar ratio), followed by carbonization and carbothermal reduction in an inert atmosphere. The oxides powder were encapsulated within the carbon gel microspheres and the elemental Sn and Sb were reduced from their oxides by the carbonized RF gel to form crystalline Sn{sub}2Sb alloy within carbon microspheres. The CM/Sn{sub}2Sb presented much better cyclability than that of Sn{sub}2Sb alloy powder. The proposed process paves an effective way to prepare high performance Sn{sub}2Sb/C microspheres composite anode materials for lithium-ion batteries.