Electrochemical investigation of polarization phenomena and intercalation kinetics of oxidized graphite electrodes coated with evaporated metal layers

The electrochemical behavior of partially oxidized graphite electrodes coated with 50 A thick Au, Cu, In, Pb or Sn layers has been studied by slow scan rate cyclic voltammetry and galvanostatic charge-discharge. Electrochemical impedance spectroscopy (EIS) has also been applied to Cu - and Sn-coated electrodes in order to study the effect of the metal coating on the interfacial intercalation/deintercalation kinetics. The results demonstrate that certain metallic layers produce remarkable improvements of intercalation kinetics of graphite electrodes by reducing the charge-transfer and the solid-electrolyte interface (SEI) resistance making this type of surface modification attractive for the development of high rate anodes for lithium-ion batteries. (C) 2008 Elsevier B.V. All rights reserved.