Electrochemical performance of a natural graphite anode was successfully enhanced by the addition of three different potassium salts into 1 mol/dm(3) LiClO4 ethylene carbonate-diethyl carbonate electrolyte. The presence of K salts in the electrolyte prior to the charge-discharge cycle considerably reduced the irreversible capacity loss at the first cycle. The reversible capacity and rate capability of the graphite anode were also improved. The electrochemical enhancement of the natural graphite anode was attributed to the mild electrolyte reduction reaction at the electrode/electrolyte interface resulting in the formation of a thin, homogenous, and more conductive solid electrolyte interface on the graphite surface. (c) 2006 The Electrochemical Society.