Surface Modification of Over-Lithiated Layered Oxides with PEDOT:PSS Conducting Polymer in Lithium-Ion Batteries

Abstract

Over-lithiated layered oxide (OLO) materials were coated with a PEDOT:PSS conducting polymer via a simple wet-coating method. The prepared samples were observed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The electrochemical properties of the samples were determined by galvanostatic testing and electrochemical impedance spectroscopy (EIS). PEDOT: PSS coated cathode materials showed better rate capability and cyclability between 2.0 V and 4.6 V. X-ray photoelectron spectroscopy (XPS) data imply that the improved electrochemical performance of coated OLO is due to the suppression of the formation and growth of the solid electrolyte interface. (C) The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. All rights reserved.