Journal article
Durability Study of SOFCs Under Cycling Current Load Conditions
Electrochemical Evaluation, Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark1
Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark2
Risø National Laboratory for Sustainable Energy, Technical University of Denmark3
Electroceramics, Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark4
In fuel cell applications, the cells must be able to withstand varying operating conditions. Anode supported solid oxide fuel cells were tested under cycling current load in order to determine the durability and possibly identify degradation mechanisms. At 750 °C and a cycling between zero and 0.75 A cm-2, the cell voltage degradation rate was similar to tests with the corresponding high constant current density.
However, by analyzing the impedance spectra it was found that anode degradation was becoming more important when going from constant to cycling conditions. Running the cycling load tests at 850 °C, the cells degraded similarly as under the corresponding constant current load whereas, in some cases, cells failed mechanically after a few hundred hours.
These cells did not experience severe additional degradation due to the cycling of the current density until the point of failure. The mechanical failure could be avoided if the cells were sealed to an interconnect rather than directly to an alumina test house. The degradation is discussed in the light of testing setup and conditions and cycling parameters.
A mechanical analysis of the occurring problems is provided as well.
Language: | English |
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Publisher: | WILEY-VCH Verlag |
Year: | 2009 |
Pages: | 814-822 |
ISSN: | 16156854 and 16156846 |
Types: | Journal article |
DOI: | 10.1002/fuce.200900013 |
ORCIDs: | Hagen, Anke , Hendriksen, Peter Vang , Frandsen, Henrik Lund and Thydén, Karl Tor Sune |