Reversible Metal Supported Solid Oxide Cells

Abstract

Solid oxide cells (SOCs) can operate in fuel cell and electrolysis mode, allowing for production of electricity and heat from a green fuel, and for storage of electricity as gas or use as fuel. Lifetime and costs are major factors enabling commercialization. Metal supported SOCs (MSCs) provide cost-competitive materials within the cell. The present study investigates the reversible operation of MSCs, fabricated by tape casting, lamination, and screen-printing, at 650 oC in 50/50 steam/hydrogen gas. In the initial few hundred hours, the MSC show a lower degradation rate compared to a state-of-the-art (SoA) fuel electrode supported cell in the electrolysis mode, while it is ca. comparable in fuel cell mode. Electrochemical impedance evaluation revealed that the degradation is due to a simultaneous increase of the serial and polarization resistances in the MSC while it is mainly due to increase of the polarization resistance in the SoA cell.