Suppression of PC decomposition at the surface of graphitic carbon by Cu coating

Cu-coated graphitic carbon was prepared by an electroless plating method, and its physical and electrochemical performance was studied by X-ray diffraction, scanning electronic microscopy, cyclic voltammetry, and measurement of discharge and charge behavior. Copper was uniformly coated on the surface of graphitic carbon. The Cu coating layer prevents the direct contact of electrolyte with the active surface of the graphitic carbon and is probably a part of solid-electrolyte interface (SEI) film. As a result, it suppresses the decomposition of propylene carbonate (PC) and exfoliation of graphite. In a PC-based electrolyte containing 50%(volume) PC, the Cu-coated graphitic carbon markedly shows better electrochemical performance with good cycling as an anode material than original graphitic carbon. This method provides a promising application of lithium ion batteries in low temperature such as -60 degrees C. (c) 2006 Elsevier B.V. All rights reserved.