Electrochemical Behavior of Supercapacitor Electrodes Based on Activated Carbon and Fly Ash

Abstract

The possibility of applying fly ash from power plants as a binder in supercapacitor electrodes based on activated carbon was investigated in this research. Based on the mechanical and electrical properties of the electrodes, the optimal ratio between fly ash and AC was determined. Supercapacitor electrodes were prepared in two ways: by pressing and by laser solidification. The preparation method significantly affected physical properties of the electrodes as well as the electrochemical behavior in supercapacitor setup. The electrodes were electrochemically tested by galvanostatic and potentiostatic methods and cyclic voltammetry. In order to improve the estimation of supercapacitor parameters, mathematical model that perfectly describes the behavior of investigated electrodes in aqueous solution of sodium nitrate was developed. The best results were obtained with laser-solidified electrode in 1M aqueous solution of NaNO 3 . Specific capacitance of 105 F/g, serial resistance of 0.57 Ω and self-discharge resistance of 95 Ω were achieved. Stability at high number of cycles proved to be very good. After 2000 cycles of CV at scan rate of 100 mV/s, specific capacitance fell by only 4.6 %.

Status of fly ash-derived sustainable nanomaterials for batteries and supercapacitors

“…The specific capacitance only decreased by 4.6%, following 2000 CV cycles at a scan rate of 100 mV s −1 . 136…”

Development of coal fly ash modified graphite-polyurethane composite electrodes for the determination of Cd(II) in batteries and water

“…However, at higher FA loadings (ca. 10% (m/m)) the interaction with the metallic species is less signi cant than the occupation of the conductive graphite sites, resulting in a decreased current 9,11 .…”

“…FA particles present interesting physical features such as a spherical morphology, relatively low particle size distribution, smooth surface topography and high thermal stability, leading to a pursuit of highly valuable applications e.g., its potential application as polymer ller 8 . The only reference found in literature regarding the electrochemical application of FA relates to the use of FA as binder in supercapacitor electrodes, based on activated carbon, for the determination of speci c capacitance 9 .…”