Metal Supported Solid Oxide Cells with Multi-layered Thin Film Electrolyte Assembly

Metal supported solid oxide cells (MS-SOCs) are of great importance for energy conversion devices, especially for mobile applications, due to the unique mechanical properties and potentials for reduction of manufacture cost. To avoid sintering process at high-temperature, a multi-layered thin-film electrolyte assembly of yttria stabilized zirconia (YSZ) and gadolinium doped ceria (GDC) has been developed through a combination of the dip-coating method and the electron beam physical vapor deposition (EB-PVD) at reduced processing temperature. Applying lanthanum strontium titanate (LST) based anode as intermediate supporting layer, the multi-layered electrolyte assembly with total thickness around 3 µm has been successfully implemented on metal supported half cells with size up to 9 x10 cm². Air leakage rate down to 0.5 Pa·m·s-1 has been achieved on the half cells. At 0.7 V, full cells with 4x4 cm² active lanthanum strontium cobalt ferrite (LSCF) cathodes demonstrated power density of 430 mW/cm² and 520 mW/cm² at 750 °C and 800 °C, respectively. Long term operation in fuel cell and electrolysis mode has been carried out over 2000 hours. The microstructure and the electrochemical performance of full cells have been investigated and discussed in detail. The research leading to these results are funded by the European Union‘s Seventh Framework Programme (FP7/2007-2013) for the Fuel Cells and Hydrogen Joint Technology Initiative under grant agreement n° 303429 (EVOLVE).