Performance and Durability of Solid Oxide Electrolysis Cells

Abstract

Solid oxide fuel cells produced at Risø National Laboratory have been tested as electrolysis cells by applying an external voltage. Results on initial performance and durability of such reversible solid oxide cells at temperatures from 750 to 950°C950°C and current densities from −0.25A∕cm2to−0.50A∕cm2−0.25A∕cm2to−0.50A∕cm2 are reported. The full cells have an initial area specific resistance as low as 0.27Ωcm20.27Ωcm2 for electrolysis operation at 850°C850°C . During galvanostatic long-term electrolysis tests, the cells were observed to passivate mainly during the first ∼100h∼100h of electrolysis. Cells that have been passivated during electrolysis tests can be partly activated again by operation in fuel cell mode or even at constant electrolysis conditions after several hundred hours of testing.