Expanded graphite@SnO₂@ polyaniline Composite with Enhanced Performance as Anode Materials for Lithium Ion Batteries

The drastic volume change is the major drawback limiting stannic oxide as an anode material for lithium ion batteries. In this work, three-dimensional (3D) EG@SnO₂@PANI composite is synthesized via solvothermal method followed by in-situ oxidative polymerization. Compare with the bare SnO₂ and EG@SnO₂ samples, the rate performance and cycling stability of the EG@SnO₂@PANI sample have been enhanced, which can be attributed to the dual conductive networks of polyaniline (PANI) with expanded graphite (EG). As a result, the 3D EG@SnO₂@PANI composite not only delivers a higher initial columbic efficiency of 77.8%, an excellent initial reversible capacity of 1021 mAh g⁻¹ at a current density of 0.1 A g⁻¹ but also still maintains at 408 mAh g⁻¹ after 100 cycles. And it exhibits enhanced rate performance, which remains at 270 mAh g⁻¹ with 2 A g⁻¹. Consequently, preparing EG@SnO₂@PANI is a suitable strategy to develop SnO₂ anode materials for lithium batteries.