I would like to know more details on fitting the Cole-Cole plot of Polymer electrolytes. How to find the equivalent circuit and circuit parameters. Any free software available?
You can fitting the Nyquist plot with excel without using any other software. In fitting method, a Nyquist plot consists of a depressed semicircle and tilted spike is equivalent to the resistor in parallel with constant phase element (CPE) and in series with another CPE. By fitting the Nyquist plot with derivative equivalent circuit equation, you can get the parameters that you are looking for.
For more details, please refer the paper below
Article A method based on impedance spectroscopy to determine transp...