Preparation of LiV3O8/Polypyrrole and Their Derived LiV3O8/Carbon Composites as Cathode Materials for Lithium Rechargeable Batteries

摘要

In this work, LiV3O8/polypyrrole composites were prepared by the in-situ polymerization method and then LiV3O8/cabon composites were also obtained by heating the corresponding LiV3O8/polypyrrole composites at 500 degrees C in air for 5 h. The as-synthesized active powders were investigated by X-ray diffraction, scanning electron microscopy, galvanostatic discharge charge, cycle voltammetry, and electrochemical impedance spectroscopy. The results show that the 10 wt%-LiV3O8/polypyrrole composite maintains a capacity of 242.49 mA h g(-1) at 30th cycle, higher than the bare LiV3O8. Meanwhile, the 10 wt%-LiV3O8/carbon composite also exhibits excellent reversibility and cycling stability, and the reversible capacity of 10 wt%-LiV3O8/carbon composite is also higher than that of the bare LiV3O8 after 17 cycles, showing a capacity of 240.80 mA h g(-1) at 30th cycle. The improved electrochemical performances of LiV3O8 composites should be attributed to their perfect structure and better interfacial compatibility.