Advanced Coal Research - Sealing Systems for High Temperature SOFC

In planar Solid Oxide Fuel Cells (SOFC), separation of the anode and cathode side gases are achieved by hermetic seals. These seals may be rigid, compressive, or compliant. However, the design of improved sealing materials must address two major challenges: (1) mechanical stability of the seals in the face of thermal cycling, and (2) chemical stability with respect to the metallic interconnect. This project will add a nanosize oxide to a prevalent glass composition, along with a novel non-reactive protective coating on the sealing area of the interconnect. In Phase I, the proposed nanosize-oxide-enhanced glass was characterized for its crystalline-phase development and thermal expansion. A novel protective coating was applied on the interconnect by a spray technique. In leak tests and stack tests, the new materials performed better than conventional state-of-the-art materials and showed promise for improved long term performance. In Phase II, the base glass composition will be fine-tuned, a superior protective coating technique will be perfected, and the material will be characterized, both by itself and in the stack environment. Commercial Applications and other Benefits as described by the awardee: The technology should lead to the development of viable sealing solutions for planar SOFC modules, which are preferred for their higher current density. An effective sealing solution should provide an impetus to clean and efficient energy generation