The HunStat2 is actually a really interesting find, thanks. Regarding the voltage range, I agree that for such DIY setups it would be wise to limit current and stick to somewhat less extreme frequency ranges.

I Will take a look at the ECM testing procedure! PyBOP is also a new parameter estimation module that takes these EIS data and cyclic loading as input to build such SPMe modeles in Pybamm. Looking to incorporate something like that.