Supercapacitor characterization
Many electrochemical methods can be used to characterize supercapacitor materials:
- Cyclic voltammetry (CV) yields estimates for the specific capacitance, doping onset potential, electrochemical stability window, rate performance, cycle life, and more.
- Chronopotentiometry (“constant current”) is mostly used to determine specific capacitance and cycle life.
- Chronoamperometry (“constant potential”) can demonstrate fast charging capabilities.
- Electrochemical impedane spectroscopy (EIS) deconvolutes many properties such as charge transfer resistance, specific capacitance, and diffusion.
PEDOT:PSS – An electronically conducting polymer
In this application note we demonstrate the electrochemical characterization of a PEDOT:PSS conducting polymer supercapacitor using the TSC Surface cell. The specific capacitance determined by CV and EIS agreed well. As expected, the charge transfer resistance fitted from the EIS data decreased by about two orders of magnitude when the DC potential was increased above the doping onset potential found by CV. The activation energy of the charge transfer could easily be determined thanks to the automated temperature control of the Microcell HC system.
To cite this application note, please use: “Karlsson et al, rhd instruments GmbH & Co. KG, Application Note: Electrochemical characterization of a conducting polymer, May 2023, https://docs.rhd-instruments.de/appnotes/application-note_TSC_Surface_PEDOT.pdf”.