PERFORMANCE OF DOUBLE-LAYER ELECTROLYTE CELLS .1. MODEL BEHAVIOR

The present work reports on the estimated performance of double layer electrolyte based cells, including one yttria stabilized zirconia (YSZ ) electron blocking layer. In order to evaluate the impact of the rela tive magnitude of the materials properties on the cell performance, a range of electrical properties has been considered, taking YSZ as refe rence. At constant temperature, the open circuit voltage, the oxygen p ermeability and the oxygen partial pressure profiles in such two layer electrolyte cells are related to the materials ionic and electronic t ransport properties, layers thickness and overall cell oxygen partial pressure boundary conditions. The effectiveness of the electron blocki ng characteristics of YSZ layers is demonstrated for a variety of mate rials, but consideration of the exact electrical properties (the n-typ e but also the p-type and ionic conductivities) of the second electrol yte layer is shown to be a fundamental requirement for proper design o f such cells.