Electrochemical behaviors of porous SnO2–Sn/C composites derived from pyrolysis of SnO2/poly(vinylidene fluoride)

► Porous SnO2–Sn/C composites were synthesized via pyrolysis of SnO2/poly(vinylidene fluoride). ► SnO2/Sn nanoparticles are encapsulated well in porous carbon matrix. ► The SnO2–Sn/C composites have good electrochemical performances even at high current densities. Porous SnO2–Sn/C composites have been synthesized via directly pyrolysis of mixtures of SnO2 powder and poly(vinylidene fluoride) without any surfactant addition and other treatment. The composites are composed of SnO2 and Sn nanoparticles which are well encapsulated in porous carbon matrix as characterized by transmission electron microscopy, X-ray powder diffraction and micro-Raman spectrometer. The obtained materials were used as anode for lithium ion batteries, a discharge capacity of 1171mAhg−1 and a charge capacity of 611mAhg−1 were shown in the first cycle at a current density of 100mAg−1, and good cycling performance achieved even at current density as high as 800mAg−1. The good electrochemical behaviors could be attributed to the formation of Sn nanoparticles which can increase the reversible capacity and the porous carbon matrix which is of excellent buffering effect and high electronic conductivity.