Electrochemical characterization of a LiV3O8-polypyrrole composite as a cathode material for lithium ion batteries

LiV3O8-Polypyrrole (LiV3O8-PPy) composite has been chemically synthesized by an oxidative polymerization of pyrrole monomer on the surface of LiV3O8 using ferric chloride as oxidizing agent. The electrochemical properties of LiV3O8-PPy composite were systematically investigated using a variety of electrochernical methods. The LiV3O8-PPy composite electrode exhibited better cycling behavior and superior rate capability as compared with the bare LiV3O8 electrode. Cyclic voltammetry corroborated the galvanostatic cycling tests, with the composite cathode material showing better reversibility than bare material. Finally, fitting the impedance results to an equivalent circuit indicated that the enhanced electrochemical performances of LiV3O8-PPy composite resulted from a facilitated kinetics of interfacial charge transfer in the presence of PPy. (C) 2011 Elsevier B.V. All rights reserved.