Analytical expressions for electrochemical supercapacitor with potential dependent capacitance. (November 2021)

• Record Type: Journal Article
• Authors: Fernandez, A.P.R.; Périgo, E.A.; Faria, R.N.
• Is Part Of: Journal of energy storage. Volume 43(2021)
• Publication Date: 2021-11
• Subjects: Supercapacitors -- Analytical expressions -- Cyclic voltammetry -- Potential dependent capacitance; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2021.103156
• Languages: English
• ISSNs: 2352-152X

Abstract

Abstract: Distinctly from ordinary capacitors which have a fixed capacitance, the capacitance of electrochemical supercapacitors is dependent on the applied potential. This feature introduces an additional complication to the analytical solution representing the supercapacitor circuit. Here a simplified equivalent circuit of electric double layer capacitors or electrochemical supercapacitors is proposed so that expressions evaluating the potential-dependent capacitance are derived considering short periods of charging and discharging process as in cyclic voltammetry carried out in a few minutes. Comparisons between such theoretical development and experimental cyclic voltammetry data – presenting a very good agreement – are presented and discussed.