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 relative magnitude of the materials properties on the cell performance, a range of electrical properties has been considered, taking YSZ as reference. At constant temperature, the open circuit voltage, the oxygen permeability and the oxygen partial pressure profiles in such two layer electrolyte cells are related to the materials ionic and electronic transport properties, layers thickness and overall cell oxygen partial pressure boundary conditions. The effectiveness of the electron blocking characteristics of YSZ layers is demonstrated for a variety of materials, but consideration of the exact electrical properties (the n-type but also the p-type and ionic conductivities) of the second electrolyte layer is shown to be a fundamental requirement for proper design of such cells.