EFFECT OF POWDER CONSOLIDATION PARAMETERS ON THE DENSITY AND PERFORMANCE OF SOLID OXIDE FUEL CELL (SOFC) ELECTROLYTES

The current research focused on the effects of powder consolidation techniques such as hot pressing (HP), spark plasma sintering (SPS) and conventional cold pressing and sintering on the density and performance of Yttria stabilized zirconia (8YSZ) Solid Oxide Fuel Cell (SOFC) Electrolyte. The effect of LiF additive on the final density and the electrolyte properties is also examined.

For oxygen ion transport in ceramic electrolytes the charge carriers are oxygen vacancies. One of the major barriers of decreasing the operation temperature is the ohmic loss of the electrolyte. The electrolyte material has a crucial influence on the fuel cell performances. An ideal SOFC electrolyte should exhibit high ionic conductivity, low electronic conductivity and good thermal and chemical stability at the operating temperatures. A fully dense structure is required in order to maximize the conductivity, minimize the reactants cross-over and reduce thermal cracking. Due to these reasons, the optimization of the consolidation parameters is of significant importance.

8YSZ due to its high ionic and low electronic conductivity is a common electrolyte material in SOFC. The assessment of the various powder consolidation approaches on the ionic conductivity and the mechanical properties of YSZ electrolytes will be discussed in details.