Synthesis of SnO2/C anode for lithium ion battery by a reflux-assisted hydrothermal method

SnO₂/C composites were synthesized by a reflux-assisted hydrothermal method using SnCl₂·2H₂O and polyvinylpyrrolidone (PVP) as raw materials. Crystalline structures and morphology of the composite particles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performacne of the composites were evaluated using Galvanostatic charge-discharge, electrochemical impedance spectrum (EIS) and cyclic voltammetry (CV) devices. The results showed that the SnO₂/PVP composites could deliver a reversible discharge capacity of 591.7 mA·h·g^-1 after 100 cycles, indicating an excellent cycling performance. High extent of dispersion of SnO₂ nanoparticles (5~10 nm) in amorphous carbon and good buffering effect to absorb the volume change of tin particles during the charging/discharging process were proposed to be the main reasons for the observed high material performance.