Interconnect Material Optimization for Low-Temperature Operation in FCH JU Project qSOFC

The optimization of the interconnect material carried out in the EU funded qSOFC project is essential to the mass production of high quality solid oxide fuel cells. Combinations of three different stainless steel grade substrates (Crofer 22H, EN 1.4622 and ASTM 441) together with two different coating compositions (CeCo and CeCoMn) as well as the impact of the use of different lubricants in the forming process have been investigated. The different combinations were exposed at 650 °C in air for more than 3500 h and ASR and SEM analysis were conducted. 441 CeCo and Crofer CeCoMn showed the best performance: ASR of 8 and 14 mΩcm2 respectively after 1000 h. They also showed very good microstructure with the formation of homogenous protective oxide scales.