Validation of and Simulations using a High-Temperature Electrolysis Model

ECS Transactions, vol. 111, pp. 1057–1066

Abstract

A continuum mechanistic, real-scale model with the most important reactions of high-temperature electrolysis is proposed. IV-characteristics and impedance spectra serve as comparison to experimental data for steam, CO2 and co-electrolysis. The exchange current-density i0 can be determined to the same order of magnitude as observed in experiments for steam electrolysis. The IV-characteristics for CO2 electrolysis are well described by an i0 one order of magnitude lower as compared to steam electrolysis. Parameter variations identify contributing variables determining the shapes of characteristics. Limitations in prediction are revealed for low current densities up to 0.5 A∙cm-2. EIS calculations demonstrate the dominant behavior of charge transfer or oxygen ion incorporation into the lattice as function of i0 or temperature. The model forms a solid basis for various future investigations like a more detailed reaction system with possible intermediates or degradation and poisoning effects.

Authors 4

1. Markus Nohl

   Forschungszentrum Jülich

   Affiliation as printed

   Inst. of Energy and Climate Research, Forschungszentrum Jülich GmbH

2. Izaak C. Vinke

   Forschungszentrum Jülich

   Affiliation as printed

   Inst. of Energy and Climate Research, Forschungszentrum Jülich GmbH

3. Rüdiger‐A. Eichel Aachen Institute of Physical Chemistry

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Inst. of Energy and Climate Research, Forschungszentrum Jülich GmbH

   RWTH Aachen University, Institute of Physical Chemistry

4. Lambertus G. J. de Haart

   Forschungszentrum Jülich

   Affiliation as printed

   Inst. of Energy and Climate Research, Forschungszentrum Jülich GmbH