Evaluation of Performance and Degradation Profiles of a Metal Supported Solid Oxide Fuel Cell Under Electrolysis Operation

Kurzfassung

In the context of energy transition, the use of renewable energies through the conversion of different resources with promising technologies into storable energy carriers is of eminent importance for a sustainable energy supply. Hydrogen production from steam using solid oxide electrolysis cells (SOEC) is part of this so called “energy mix”. Recently, promising progress appeared from the investigation of metal supports in the solid oxide cell architecture. Metal-supported solid oxide fuel cells (MS-SOFCs) show not only good mechanical strength, relatively low operating temperature (500-750°C) and improved sealing capability but also low materials cost and tolerance towards rapid thermal cycling and redox cycling (1-3). In the present study, a MS-SOFC was tested under electrolysis conditions. The cell consisted of Ni-catalyst loaded La0.1Sr0.9TiO3-α/gadolinium-doped ceria (Ni-LST/GDC) as fuel electrode, gadolinium-doped ceria / yttrium-stabilized zirconia (GDC/YSZ) as electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) as O2 electrode. The cell was first tested in fuel cell mode under different gas compositions. Subsequently, a first evaluation of the cell performance profile in electrolysis mode was performed. Thus, a series of current-voltage curves as well as impedance diagrams (under OCV and under load) was recorded. Furthermore, degradation under electrolysis operation was also investigated based on the evolution of the cell voltage against time.