<< Back to Recommended reading on EIS
If you've studied all of the previous pages in this series, why not put your new-found skills to the test with a little exercise?
Below are three plots of simulated impedance data. The data is representative of a symmetrical electrochemical cell, comprising a thin lithium-conducting polymer electrolyte with relatively poor ionic conductivity, sandwiched between two lithium metal electrodes. (Hint: this sort of system is discussed here and here.)
Exercise: from the plots below, can you propose an equivalent circuit? Once you have come up with a circuit model, can you calculate all the relevant parameters... by hand?
This is a tricky exercise. See how far you get - and if you're done or can go no further, why not try your hand at fitting the "raw" data? You can download the data here.
This exercise is a variant of one I used in teaching on a number of occasions. There are several aims here, which I believe test some of the most important skills for building real competence in the technique:
Want to check your answers? You can check how you did against the real circuit and parameters by following this link. Don't cheat!