Effect of morphology and current density on the electrochemical behavior of graphite electrodes in PC-based electrolyte containing VEC additive

The effect of graphite morphology and charge/discharge condition on the electrochemical behavior of the graphite electrodes were investigated in propylene carbonate-based electrolyte containing vinyl ethylene carbonate (VEC) as a film-forming additive. The graphite particles with different morphologies including synthetic graphite flakes and sphere-shaped graphite particles, i.e., mesocarbon microbeads (MCMB), exhibit the large difference in electrochemical behavior. The cointercalation of solvents and solvated Li+ ions into MCMB was suppressed significantly using high charge/discharge current density, which improves the electrochemical performance of the MCMB electrode. (C) 2004 The Electrochemical Society.