Electrochemical impedance spectroscopy (EIS) is a powerful analytical method that is widely
used in fuel cell and battery research. 
It enables the electrochemical properties of materials and systems to be investigated by measuring impedance as a function of frequency. This technique provides information about various processes in the cells, such as ion transport, electrical charge carrier movement and reaction kinetics, and thus contributes to optimizing the performance and service life of fuel cells and batteries.

The current amplifier is a suitable option for impedance measurement, as it can supply a
precisely adjustable direct and alternating current that is independent of the load.

A task for the HUBERT 4-quadrant power amplifier, configured in current amplifier mode.
The following chapters describe a possible test setup and commissioning. The impedance
calculation is not the subject of this application note