CFY-Stacks: Progress in Development

The development of electrolyte supported cells and the components for high efficient and robust stacks are in the focus of the R&D activities of Fraunhofer IKTS for a long time. Since 2010, the CFY-stack design MK351 is produced for a broad range of prototype applications. The change to the new design MK352 has advantages in operation, integration, quality and shall lead to a commercial production. In close collaboration with Plansee SE, a symmetrical design of the interconnect was developed, which allows the compensation of tolerances resulting from near-net shape pressing technology and simpler stack integration in modules. By revision of tolerance chains for all stack components, better robustness in manufacturing and performance has been achieved. The program of validation tests for cells, glass sealings, interconnects, protection and contact layers for the stack will be shown on the example of the new stack design MK352. CFY stacks are the heart for several SOFC/SOEC systems and shows equal characteristics for a wide operating window. The background for that will be explained in this article by testing different gas compositions with local temperature measurements inside the stack.