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

Abstract

The single-walled carbon nanotube (SWNT)/$\mathrm{Sn}{\mathrm{O}}_2$ core-shell structures with small diameters as Li-insertion materials are investigated. The initial discharge capacity is up to $1339\mathrm{mA}\mathrm{h}∕\mathrm{g}$ , and the reversible capacity retention is 89.8% after $100\text{cycles}$ , which is comparable to the performance of commercial graphite anodes. Such good electrochemical properties are attributed to large surface-to-volume ratio of $\mathrm{Sn}{\mathrm{O}}_2$ 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.