Improving the electrolyte-cathode assembly for MT-SOFC

摘要

In the long road towards commercialization of Solid Oxide Fuel Cells, improving the cathode’s performance is a major milestone. Achieving low Area Specific Resistances at temperatures around 600 °C are required to meet the market demands in terms of costs and lifetime. udIn this thesis, different research projects focusing on the electrolyte / cathode assembly are described with as aims, an improvement of the performance and a better understanding of the cells.udTo decrease the Area Specific Resistance (ASR) of the cathodes, two solutions are explored and combined in this thesis. udThe first possibility is to replace the-state-of-the-art cathode materials by new and innovative materials. A study on Lanthanum Nickelate (La2NiO4+δ) as a porous electrode is shown This material shows excellent oxygen surface exchange and ionic diffusion.udThe second possibility is to use one of the state-of-the-art materials and improve its microstructure. By engineering the electrolyte / cathode interface, it is shown for La0.6Sr0.4Co0.2Fe0.8O3-δ and for La2NiO4+δ that the oxygen surface transport on the cathode grains can be enhanced. The trick consists of introducing a thin dense layer of the cathode material between the porous electrode and the electrolyte.udFinally,a new method to produce a complete cell with Pulsed Laser Deposition is presented. PLD is a typical example of what nanotechnology can bring to improve Solid Oxide Fuel Cells.