Electrophoretically Deposited Copper Manganese Spinel Coatings for Interconnections in Solid Oxide Fuel Cells

Chromium poisoning of the cathode due to oxidation of metallic interconnections and subsequent formation of vapor phase chromium containing species is a well-known problem. The application of ceramic coatings on the interconnections to prevent this deleterious phenomenon is currently being extensively investigated. Copper manganese spinel coatings of different compositions were deposited on Crofer 22 APU substrates containing grooves, by electrophoretic deposition (EPD). Thermo-gravimetric measurements under oxidizing conditions at 800°C were carried out to study the effectiveness of the coatings as diffusion barriers. Special attention was paid to coating thickness variations and adhesion around corners and the vertical walls of the grooves. Chromium diffusion into the spinel coatings as well as area specific resistance of the coatings at 800°C are reported.