Electrochemical Impedance Spectroscopy (EIS)

Electrochemical Impedance Spectroscopy (EIS)

Typically, Electrochemical Impedance Spectroscopy (EIS) measurements are performed using a single sine excitation, which is repeated at several different frequencies. (single sine method).

EIS is commonly measured using a “single-sine” method where individual frequencies are measured sequentially. One disadvantage of single-sine EIS is the time it takes to acquire a full spectrum.

Broadband approaches (such as the multi sine method) allow for shorter measurement time and are better for online measurement and monitoring applications.

Single-Sine EIS measurements involve applying a sinusoidal perturbation (voltage or current) and measuring the response (current or voltage, respectively). The measurement is complete when it is deemed satisfactory, or some time limit is reached.

This decision requires a mathematically sound criterion for a satisfactory measurement. Gamry’s Single-Sine technique terminates the measurement at each frequency when its signal to noise ratio exceeds a target value.

References

  1. Gamry Instruments, Application Note Basics of Electrochemical Impedance Spectroscopy]. Available online https://www.gamry.com/assets/Application-Notes/Basics-of-EIS.pdf, 2010

  2. Gamry Instruments, Application Note, “OptiEIS™: A Multisine Implementation,” Available online: https://www.gamry.com/applicationnotes/EIS/optieis-a-multisine-implementation/, 2020.