High capacity and excellent cycling stability of single-walled carbon nanotube/ SnO₂ core-shell structures as Li-insertion materials

The single-walled carbon nanotube (SWNT)/ SnO₂ core-shell structures with small diameters as Li-insertion materials are investigated. The initial discharge capacity is up to 1339 mA hg, and the reversible capacity retention is 89.8% after 100 cycles, which is comparable to the performance of commercial graphite anodes. Such good electrochemical properties are attributed to large surface-to-volume ratio of SnO₂ and good electrical conductivity of SWNT. Our results demonstrate that the SWNT/core-shell structures are very promising for active Li-insertion materials for Li-ion batteries.