Effects of KCl contaminant in electrolyte on performance of graphite electrode

Electrochemical performance of natural graphite electrode cycled vs.Li in 1 mol/L LiPF6/(EC+DMC+EMC)(1∶1∶1,volume ratio) electrolyte solution, which contained different concentrations of KCl, were evaluated by charging/discharging, cyclic voltammetry. The study results show that the natural graphite electrode cycling performance and the first discharge capacity are reduced by the addition of more than 0.1% KCl to the electrolyte. Surface analyse of the graphite electrode using SEM and FTIR suggests that adding more than 0.1% KCl are not contributes to the formation of a good SEI film, influencing the electrochemical performance of graphite electrode.