Concentration dependent electrochemical performance of aqueous choline chloride electrolyte

In this work we have analysed the performance of aqueous choline chloride as an electrolyte in supercapacitors. The aqueous choline chloride electrolyte is prepared in molar concentrations of 0.3, 0.5, 0.7, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4. The different concentrations of aqueous choline chloride electrolyte are used to fabricate activated carbon electrode based supercapacitors. The prepared electrolytes are characterized using FTIR technique and their ionic conductivity and electrochemical stability window are analysed using electrochemical impedance spectroscopy and cyclic voltammetry respectively. The electrochemical stability window is found 1.8 V for all concentration of choline chloride electrolytes. The highest conductivity is 129 mS/cm for 2.5 M aqueous choline chloride and two peaks feature is observed in ionic conductivity vs. concentration of electrolyte plot. The electrochemical performance of supercapacitors is analysed using cyclic voltammetry and electrochemical impedance spectroscopy, the supercapacitors showed good charge propagation and highest specific capacitance is reported for 1.0 M electrolyte (5.75F/g).