N-doped carbon coated SnO2 nanospheres as Li-ion battery anode with high capacity and good cycling stability

The preparation of high electrochemical performance SnO2-based anode is a crucial promotion to be an alternative electrode for lithium storage. To this end, SnO2 hollow nanospheres covered with nitrogen-doped carbon shell (denote as NC@SnO2 HNSs) are designed and synthesized. The NC@SnO2 HNS electrode could not only improves the conductivity of pure SnO2 HNSs effectively, but also possesses a large proportion of the cavity (73.8 %), which could cope the strain relaxation. Benefiting from the superior structural design, the NC@SnO2 HNS electrode exhibits high reversible capacity (868.6 mAh g-1 after 200 cycles at 0.2 A g-1), long-term cycling performance (360.6 mAh g-1 after 500 cycles at 1.0 A g-1) and superior rate performance.