The performance and degradation of Solid Oxide Fuel Cells (SOFC) were studied under severe operating conditions. The cells studied were manufactured in a small series by ECN, in the framework of the EU funded CORE-SOFC project. The cells were of the anode-supported type with a double layer LSM cathode. They were operated at 750 °C or 850 °C in hydrogen with 5% or 50% water at current densities ranging from 0.25 A cm–2 to 1 A cm–2 for periods of 300 hours or more. The area specific cell resistance, corrected for fuel utilisation, ranged between 0.20 Ω cm2 and 0.34 Ω cm2 at 850 °C and 520 mV, and between 0.51 Ω cm2 and 0.92 Ω cm2 at 750 °C and 520 mV.
The degradation of cell performance was found to be low (ranging from 0 to 8%/1,000 hours) at regular operating conditions. Voltage degradation rates of 20 to 40%/1,000 hours were observed under severe operating conditions, depending on the test conditions.
Data analysis revealed a critical cell voltage of ca 750 mV, above which the degradation rates were trivial, but below which they were significant.
Some cells were also tested using a different procedure to that usually applied at Risø. This gave a different aging behaviour, indicating that the detailed test circumstances may be decisive to the outcome.
|Publication status||Published - 2006|
|Event||6th European Solid Oxide Fuel Cell Forum - Lucerne, Switzerland|
Duration: 28 Jun 2004 → 2 Jul 2004
Conference number: 6
|Conference||6th European Solid Oxide Fuel Cell Forum|
|Period||28/06/2004 → 02/07/2004|
- Accelerated test
- Cathode activation
- Impedance spectroscopy