%0 Conference Paper
%A Edeh, Obinna
%A Schäfer, Dominik
%A Eichel, Rüdiger-A.
%A Kunz, Felix
%T Detecting atypical Operation at Solid-Oxide Cells Stack using a nonlinear AC Technique: Total Harmonic Distortion (THD).
%I RWTH Aachen
%M FZJ-2023-05604
%D 2023
%X This study aims to explore the possibility of utilizing a nonlinear AC-based approach known as total harmonic distortion (THD) to monitor the operation of temperature solid oxide cell (SOC) stacks during the co-electrolysis of steam and CO2 for synthesis gas (syngas, a mixture of H2 and CO) production. The THD technique enables the online measurement of nonlinearities in electrochemical devices, providing an effective way to track certain performance changes. Like electrochemical impedance spectroscopy (EIS), the THD technique involves probing an electrochemical system with an excitation signal of a given frequency and amplitude and recording the response signal. But contrary to EIS, non-linear system responses are evaluated.This research will complement THD analysis with conventional techniques such as polarization curves, EIS, and distribution of relaxation time (DRT) to interpret the obtained data. The research will be carried out with a short stack in the Juelich F10 design employing fuel-electrode-supported cells with a substrate and fuel electrode. The THD parameters such as AC amplitude signal, direct current, harmonic orders, and frequencies that provide suitable fault detectability will be established. In this work, the nonlinear response of solid oxide electrolysis cells (SOEC) stacks resulting from high gas conversion at high current density and reactant starvation will be investigated.Previous research indicates that THD technique can detect early signs of degradation in solid oxide fuel cells (SOFC), which is essential for applying mitigation strategies to prevent irreversible damage in SOFC. However, the application of THD techniques to monitor the operation of high-temperature SOC stacks during co-electrolysis for syngas production is lacking in the literature. This study will be essential for future research involving the use ofTHD technique in monitoring degradation and optimizing SOC stack performance andespecially for power-to-syngas process.
%B International Conference on Fundamentals & Development of Fuel Cells FDFC Ulm 2023.
%C 25 Sep 2023 - 27 Sep 2023, Ulm (Germany)
Y2 25 Sep 2023 - 27 Sep 2023
M2 Ulm, Germany
%F PUB:(DE-HGF)6
%9 Conference Presentation
%U https://juser.fz-juelich.de/record/1019773