Voltage and Frequency Dependent Impedances of Dye-sensitized Solar Cell

This paper describes a derivation of the dynamic impedance of a dye-sensitized solar cell (DSSC) and its characterization using a frequency response analyzer (FRA). The dynamic impedance equation as a function of voltage and frequency is presented. Testing is done on a DSSC, fabricated from a fluorine-doped SnO2 (FTO) conducting glass, ruthenium (II) dye (N719) sensitized TiO2 nanoparticles, an iodide-triiodide electrolyte, and a Pt counter electrode. At each bias voltage, impedance locus is plotted in a complex plane. Intercepts of each semicircular impedance loci yield series, dynamic, and shunt resistance of the cell. Experimental results could be used to analyze characteristics of AC equivalent circuit components.