Impedance, admittance, Nyquist, Bode, Black, (EIS plot) – Battery – Application Note 8Latest updated: August 31, 2021
In impedance spectroscopy either a voltage wave is applied and current is measured, or current is applied and the voltage is measured. Whichever way the data is obtained, it contains a current-voltage characteristic for a number of frequencies. Therefore each data point contains either modulus and phase angle, or real and imaginary part (these two options are 100% equivalent) of impedance or admittance (and these two options are also 100% equivalent), and a frequency. So whichever way it’s plotted, as long as it’s a 2D plot, it only shows a certain representation of the data, that is missing the third dimension, be it plotting impedance or admittance, in Nyquist, Bode or Black representation.
Researchers from different fields have personal, but mostly historical preferences towards one representation or another. This Application Note explains how they are constructed and how they are all available to users of Bio-Logic potentiostats-galvanostats-ZRAs and battery cyclers.