Courses » Electrochemical Impedance Spectroscopy

Electrochemical Impedance Spectroscopy


This course will introduce electrochemical impedance spectroscopy technique and illustrate its use to characterize electrochemical processes. Details regarding correct method of data acquisition and analysis, along with pitfalls to watch out for, will be discussed

PG students, working on electrochemical research




INDUSTRY SUPPORT: Battery and electric vehicle (EV) companies, those where corrosion is a key problem, or those working in electroplating, will find this useful

440 students have enrolled already!!


S. Ramanathan is a Professor in Dept. Chem. Engg. IIT Madras. His research interests include general electrochemistry (corrosion, electrodeposition etc.) and mechanistic analysis of electrochemical reactions using of electrochemical impedance spectroscopy (EIS). In addition, we have developed new experimental tools and simulation methods to extend the EIS to nonlinear regime.


Week 1  :  Introduction to electrochemistry, electrode-electrolyte interface, reference electrode, three electrode cell, supporting electrolyte, rate constant, EIS basics, electrical elements, differential impedance, time domain results, graphical representation of impedance data in Bode and Complex plane plots, other techniques
Week 2  :   Experimental details: Instrumentation, single and multi-sine inputs, FFT details, frequency range and resolution, cross correlation, multi sine: odd harmonics and non-harmonic choices, crest factor, spectral leakage, windowing
Week 3  : Data validation: Kramers Kronig Transforms (KKT), Linearity, causality, stability, impedance vs. admittance, applications and limitations, Alternatives – measurement model analysis and linear KKT
Week 4  :  Data analysis: Electrical Equivalent Circuits, choice of circuits, confidence intervals, AIC, initial values, distinguishability, zeros and poles representation, charge transfer resistance and polarization resistance, Maxwell, Ladder and Voigt circuits
Week 5  :  Reaction mechanism analysis, linearization of governing equations, derivation of impedance expression for a simple electron transfer reaction; two step reactions with one adsorbed intermediate
Week 6  :  Reaction mechanism analysis (continued), development of impedance expression for multiple reactions, an example reaction exhibiting negative resistance, an example three step reaction with 2 adsorbed intermediates
Week 7  :  Reaction mechanism analysis (continued), development of impedance expression for a catalytic reaction exhibiting negative resistance, reactions with Frumkin isotherm practical challenges in extraction of kinetic information, list of various patterns of complex plane plots reported in literature
Week 8  :  Diffusion effects, Warburg Impedance, finite and semi-infinite cases, effect of change in dc potential and boundary layer thickness.
Week 9  :  Constant phase elements (CPE), porous electrodes
Week 10  :  Passivation and film formation, point defect model (PDM) and extensions. Description of a few selected applications of EIS: Corrosion, biosensors, fuel cells, mechanistic analysis
Week 11  :  Nonlinear EIS (NLEIS), introduction, mathematical background (Taylor series, Fourier series, modified Bessel functions), NLEIS for a simple electron transfer reaction, reaction with adsorbed intermediates, Nonlinear charge transfer and polarization resistances
Week 12  :  Effect of instabilities in traditional EIS- calculation using NLEIS methodology, solution resistance effects, Detection of nonlinearities using KKT, NLEIS with Frumkin and Temkin isotherm, evaluation of related technique: electrochemical frequency modulation (EFM)


•    1. M.E. Orazem, B. Tribollet, Electrochemical impedance spectroscopy, John Wiley & Sons, New York, 2011.

2. A. Lasia, Electrochemical Impedance Spectroscopy and its Applications, Springer, New York, 2014.

3. E. Barsoukov, J.R. Macdonald, Impedance spectroscopy: theory, experiment, and applications, John Wiley & Sons, New York, 2005.

4. V.F. Lvovich, Impedance spectroscopy: applications to electrochemical and dielectric phenomena, John Wiley & Sons, New York, 2012.

  • The exam is optional for a fee.
  • Date and Time of Exams: April 27 2019 (Saturday)  Morning session 9am to 12 noon; Afternoon Session 2pm to 5pm.
  • Registration url: Announcements will be made when the registration form is open for registrations.
  • The online registration form has to be filled and the certification exam fee needs to be paid. More details will be made available when the exam registration form is published.


  • Final score will be calculated as : 25% assignment score + 75% final exam score
  • 25% assignment score is calculated as 25% of average of  Best 8 out of 12 assignments
  • E-Certificate will be given to those who register and write the exam and score greater than or equal to 40% final score. Certificate will have your name, photograph and the score in the final exam with the breakup.It will have the logos of NPTEL and IITMadras.It will be e-verifiable at nptel.ac.in/noc.