Features of Electrochemical behavior of Porous Carbon Electrodes of Supercapacitor in Aqueous Solutions of Alkali Metal Salts

Abstract

UDC 544.636+546.26

DOI  https://doi.org/10.5281/zenodo.1051314

Electrochemical behavior of porous carbon electrodes of different density (0.75 and 0.35 g/cm³) used in supercapacitors with aqueous solutions of lithium, sodium and potassium sulfates was studied. It was shown that Li₂SO₄ solution is the most suitable for high-dense electrodes, while K₂SO₄ solution is better to utilize for electrodes of low density. Experimental data obtained by means of cyclic voltammetric and impedance curves demonstrate mutual influence of porous structure of the electrode materials and diameters of solvated and bare ions on the values of specific capacitance and resistance. This should be taken into account when electrode / electrolyte system is chosen for high-efficiency energy storage devices.

Keywords: porous carbon electrode, alkali metal salt, supercapacitor.