This work reports on the estimated performance of double layer electro
lyte cells consisting of one gadolinia doped ceria (GCO) supporting la
yer covered by one yttria stabilized zirconia (YSZ) electron blocking
layer. The latter might be located either on the cell cathode or anode
side. Cell characterization includes estimates of the open circuit ox
ygen permeability and voltage deviation form pure Nernstian behaviour,
and on the open circuit and shorted circuit electrolyte/electrolyte i
nterfacial oxygen partial pressures. These parameters were estimated b
ased on materials electrical properties (ionic, n-type and p-type cond
uctivities), assumed layers thickness (50-200 mu m for GCO and 10(-3)
to 10 mu m for YSZ) and cell operating temperatures (800 and 1000 degr
ees C), at constant oxygen partial pressure boundary conditions (0.21
and 10(-20) atm). The electron blocking characteristics of YSZ layers
is demonstrated for both cell configurations, and possible advantages
of both concepts are discussed.