Electrochemical Impedance Analysis of SOFC Cathode Reaction Using Evolutionary Programming

Abstract

Investigation of the cathode reaction in solid oxide fuel cells (SOFC) by impedance spectroscopy (IS) measurements using evolutionary‐based programming analysis is demonstrated. In contrast to the conventional analysis methods used for impedance spectroscopy measurements, e.g., equivalent circuits, the impedance spectroscopy genetic programming (ISGP) program seeks for a distribution of relaxation times that has the form of a peak or a sum of several peaks, assuming the Debye kernel. Using this method one finds a functional (parametric) form of the distribution of relaxation times. A symmetric cell configuration of Pt|LSCF|GDC|LSCF|Pt was examined using IS measurements combined with I–V measurements. Different samples at different temperatures and different oxygen partial pressures were examined in order to investigate their influence on the oxygen reduction reaction. The resulting IS data was analyzed using the ISGP program and the resulting peaks constructing the distribution of relaxation times were assigned for the different processes that occur at the cathode side. The activation energies as well as the dependence of the processes on the oxygen partial pressure were also evaluated.

Electro‐chemomechanical Contribution to Mechanical Actuation in Gd‐Doped Ceria Membranes

“…Partial identification of the features of the impedance spectra of the membranes were made previously . In the current work, ISGP was implemented because of its proven ability to distinguish between dielectric response and electrochemical response in fuel cells, batteries and super‐capacitors . The program determines the extent to which the Kramers‐Kronig (KK) relations are obeyed by the real and imaginary parts of the complex impedance data (Section S3, Supporting Information)…”

Understanding methods of preparation and characterization of pore-filling polymer composites for proton exchange membranes: a beginner’s guide

“…Several different ECs can result in the same spectrum, leading to completely different physical interpretations (Baltianski and Tsur 2003). Thus, other modern analysis techniques, notably Impedance Spectroscopy Genetic Programming (ISGP) (Hershkovitz et al 2011, Hershkovitz et al 2012, Drach et al 2016, Oz et al 2016, Oz et al 2017, analyzing distribution of relaxation times in the system, and mechanistic models (Amphlett et al 1995, Springer et al 1996, Franco et al 2007, Reshetenko and Kulikovsky 2017, are being also employed.…”

Electrochemical impedance spectroscopy of supercapacitors: A novel analysis approach using evolutionary programming

“…This model is usually comprised of an additional parameter, R 0 , accounts for series resistance. Our previous work [11] have shown that series resistance results in a single peak in the DFRT outside the measured bandwidth, at high frequencies, so it will not be discussed in this paper.…”

“…This equation is an ill-posed inverse problem which cannot be solved directly. In order to find the DFRT model that fits best the measured data we analyze it using Impedance Spectroscopy Genetic Programming (ISGP) [8][9][10][11], a novel technique to find a functional form of the DFRT using a genetic algorithm. It starts with an initial guess of models, each model comprised of a combination of one or more known mathematical peaks (e.g.…”