Investigation and Design Studies of SOFC Electrode Performance at Elevated Pressure [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 621.31 Generation, modification, storage, transmission of electric power
• Thông tin xuất bản: Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2010
• Mô tả vật lý: Medium: ED : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 256974
• Chủ đề: 1. 30 direct energy conversion; 2. Atmospheric pressure; 3. Cathodes; 4. Design; 5. Diffusion; 6. Electrodes; 7. Et al; 8. Fuel cells; 9. Oxygen; 10. Partial pressure; 11. Performance

Tóm tắt

An experimental program was set forth to study fuel cell performance at pressure and under various compositions. Improvement in cathode electrode performance is on the order of 33-40% at pressures of 6.4 Bara compared to atmospheric pressure. Key cathode operational parameters are the concentration and partial pressure of O2, and temperature. The effect of partial pressure of oxygen (PO2) decreases the activation polarization, although there appears to be a secondary effect of absolute pressure as well. The concentration of oxygen impacts the diffusion component of the polarization, which is largely insensitive to absolute pressure. The effect of pressure was found to reduce the total polarization resistance of full fuel-cells beyond the reduction determined for the cathode alone. The total reduction in ASR was on the order of 0.10 ohm-cm2 for a pressure increase from 1 to 6.5 Bara, with about 70% of the improvement being realized from 1 to 4 Bara. An important finding was that there is an effect of steam on the cathode that is highly temperature dependent. The loss of performance at temperatures below 850 C was very large for the standard LSM + YSZ cathodes.