Abstract
The EU Integrated Project Real-SOFC aims at improving the
understanding of degradation in SOFC stacks and extending
the durability of planar SOFC stacks to degradation rates
suitable for stationary application. As part of the
Real-SOFC project three series of SOFC stacks each with 2
or 4 planar anode-supported cells were operated for
durations of up to 3000 h (and longer) under varying fuel
and electrical load conditions. The durability tests on
these short stacks were conducted galvanostatically at
800 and 700 °C in dependence of current-density (0.3, 0.5
or 0.7 A/cm²), of fuel composition (hydrogen: H2 + 3.10%
H2O or methane: CH4/H2O (S/C=2)) and of fuel utilization
(8, 40, 60 or 75%). A pronounced difference in
degradation behaviour was observed between the stacks
operated at different current densities. The degradation
behaviour was, however, not influenced by the choice of
fuel (hydrogen or methane) and was hardly influenced by
the fuel utilization. Lowest degradation rates of about
20 m?ocm²/kh were determined for the tests of a short
stack with cells with LSM cathodes operated at 800 °C and
a current-density of 0.3 A/cm² and of a short stack with
cells with LSCF cathodes operated at 700 °C and a
current-density of 0.5 A/cm².
Post-test characterization of the cathode with respect to
chromium poisoning was performed on cells from several
stacks. No clear relationship between the degradation
rate of the stacks and amount of Cr incorporated in the
cathode could be established. The major difference was a
change in microstructure of the cathode in the region
near the electrolyte interface; in the stacks operated at
lower current densities the structurally changed zone was
clearly thinner than in those stacks operated at higher
currents.
Original language | English |
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Title of host publication | 8th European SOFC Forum |
Subtitle of host publication | European Solid Oxide Fuel Cell Forum Proceedings |
Publisher | European Fuel Cell Forum AG |
Publication status | Published - 2008 |
MoE publication type | B3 Non-refereed article in conference proceedings |
Event | 8th European SOFC Forum, EFCF 2008: European Solid Oxide Fuel Cell Forum - Lucerne, Switzerland Duration: 30 Jun 2008 → 4 Jul 2008 |
Conference
Conference | 8th European SOFC Forum, EFCF 2008 |
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Abbreviated title | EFCF 2008 |
Country/Territory | Switzerland |
City | Lucerne |
Period | 30/06/08 → 4/07/08 |