In this 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 La_0.1Sr_0.9TiO_3-α/gadolinium-doped ceria (Ni-LST/GDC) as fuel electrode, gadolinium-doped ceria/yttrium-stabilized zirconia (GDC/YSZ) as electrolyte and La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF) as O₂ electrode. After a short testing period in fuel cell mode, 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 for different fuel electrode gas compositions. Furthermore, degradation under electrolysis operation was also investigated based on the evolution of the cell voltage against time for several currents applied. Consequently, analysis of the post-mortem characterization by SEM/EDX, along with the electrochemical testing results, aims at identifying the changes in cell characteristics specifically related to degradation under electrolysis operating conditions.

[1] M. C. Tucker, J. Power Sources 195 (2010) 4570-4582.

[2] J. T.S. Irvine, J. Bae, J-Y Park, W. S. Choi, J. H. Kim, Int. J. Hydrogen Energy, In Press-Corrected Proof.

[3] A. M. Dayaghi, K. J. Kim, S. Kim, J. Park, S. J. Kim, B. H. Park, G. M. Choi, J. Power Sources 324 (2016) 288-293.