(Invited) Beyond Electrochemical Impedance Spectroscopy: Advanced Methods for Studying the Dynamics of Electrochemical Processes

Abstract

The most popular technique for characterizing various electrochemical devices such as fuel cells, water electrolysis or batteries is electrochemical impedance spectroscopy (EIS). However, due to the coupling of dynamic phenomena with similar time constants, EIS often fails to separate the contributions of individual processes to overall performance losses. In this case, obtaining useful information from the EIS spectra can be be difficult and the interpretation of the observed patterns is unclear. In this talk, I show that new dynamical methods based on the use of nonlinearities in the system response (nonlinear frequency response analysis (NFRA) [1]), non-electrical inputs (concentration-alternating frequency response analysis (cFRA) [2]), or data-driven analyses (Loewner framework [3]) can provide additional information for understanding electrochemical conversion processes. Our current examples are related to the study of polymer electrolyte membrane electrolysis and polymer electrolyte membrane fuel cell. References [1] Vidaković-Koch T., Miličić, T., Živković, L.A., Chan, H.S., Krewer, U., Petkovska, M., (2021) Nonlinear Frequency Response Analysis: A Recent Review and Perspectives, Current Opinion in Electrochemistry, 100851. [2] Sorrentino, A., Sundmacher, K. & Vidaković-Koch, T. (2020). Polymer Electrolyte Fuel Cell Degradation Mechanisms and Their Diagnosis by Frequency Response Analysis Methods: A Review. Energies, 13(21), 5825. [3] Antoulas, A. C., Lefteriu, S., and Ionita, A. C., (2017) A tutorial introduction to the Loewner framework for model reduction in Model Reduction and Approximation, Eds: P. Benner, A Cohen, M. Ohlberger, K. Willcox, Siam Comupational Science and Engineering, Chapter 8, pp. 335–376.

Keywords

Identifiers

DOI

10.1149/ma2023-02371793mtgabs

Journal

ECS Meeting Abstracts

Year

2023