A simple and feasible technique is developed successfully to fabricate the cone-shaped tubular segmented-in-series solid oxide fuel cell (SOFC) stack. The cone-shaped tubular anode substrates and yttria-stabilized zir...
详细信息
A simple and feasible technique is developed successfully to fabricate the cone-shaped tubular segmented-in-series solid oxide fuel cell (SOFC) stack. The cone-shaped tubular anode substrates and yttria-stabilized zirconia. (YSZ) electrolyte films are fabricated by dip coating technique. After sintering at 1400 degrees C for 4 h, a dense and crack-free YSZ film with a thickness of about 35.9 mu m is successfully obtained. The single cell, NiO-YSZ/YSZ/LSM-YSZ, provides a maximum power density of 1.08 and 1.35 W cm(-2) at 800 and 850 degrees C, respectively, using moist hydrogen (75 ml/min) as fuel and ambient air as oxidant. A two-cell-stack based on the above-mentioned cone-shaped tubular anode-supported SOFC was assembled and tested. The maximum total power at 800 degrees C was about 3.7 W. (C) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.
A novel design of cone-shaped tubular segmented-in-series solid oxide fuel cell (SOFC) stack is presented in this paper. The cone-shaped tubular anode substrates are fabricated by slip casting technique and the yttria...
详细信息
A novel design of cone-shaped tubular segmented-in-series solid oxide fuel cell (SOFC) stack is presented in this paper. The cone-shaped tubular anode substrates are fabricated by slip casting technique and the yttria-stabilized zirconia (YSZ) electrolyte films are deposited onto the anode tubes by dip coating method. After sintering at 1400 degrees C for 4 h, a dense and crack-free YSZ film with a thickness of about 7 mu m is successfully obtained. The single cell, NiO-YSZ/YSZ (7 mu m)/LSM-YSZ, provides a maximum power density of 1.78 W cm(-2) at 800 degrees C, using moist hydrogen (75 ml min(-1)) as fuel and ambient air as oxidant. A two-cell-stack based on the above-mentioned cone-shaped tubular anode-supported SOFC is fabricated. Its typical operating characteristics are investigated, particularly with respect to the thermal cycling test. The results show that the two-cell-stack has good thermo-mechanical properties and that the developed segmented-in-series SOFC stack is highly promising for portable applications. (C) 2009 Elsevier B.V. All rights reserved.
segmented-in-series solid oxide fuel cells with relatively short cell lengths of 1.4 mm were fabricated with varying LSM cathode current collector thicknesses. Increasing the LSM thickness from 11 to 91 mu m yielded a...
详细信息
segmented-in-series solid oxide fuel cells with relatively short cell lengths of 1.4 mm were fabricated with varying LSM cathode current collector thicknesses. Increasing the LSM thickness from 11 to 91 mu m yielded a factor of 2-3 area-specific resistance decrease and a similar power density increase. The maximum power density measured at 800 degrees C was 0.53 W cm(-2) calculated based on total array area (including interconnect), and 0.9 W cm(-2) calculated based on active cell area. A segmented-in-series electrical model was used to quantitatively explain the results based on the decreased cathode sheet resistance. The model also showed that the cell lengths were near optimal for maximizing the power density of these cells. (c) 2006 Published by Elsevier B.V.
segmented-in-series solid oxide fuel cells (SIS-SOFCs) were prepared on flattened-tube partially stabilized zirconia supports. The distinguishing characteristic of these cells was the short repeat period, 2.4 mm, and ...
详细信息
segmented-in-series solid oxide fuel cells (SIS-SOFCs) were prepared on flattened-tube partially stabilized zirconia supports. The distinguishing characteristic of these cells was the short repeat period, 2.4 mm, and small active cell length, 1.3 min, compared to approximate to 10 mm in previous SISSOFCs. The support tubes, formed by gelcasting, were bisque fired and then screen printing was used to sequentially deposit Ni-YSZ anodes, YSZ electrolytes, and Pt-YSZ composite interconnects. After high-temperature co-firing, LSM-YSZ and LSM cathode layers were screen printed and fired. Each flattened tube side had 12-16 individual cells. For testing, the open tube ends were sealed and humidified hydrogen flowed inside of the tubes;air was flowed over the outside of the tubes. Maximum total power at 800 degrees C was approximate to 8 W and maximum power density was approximate to 0.7 W cm(-2), calculated using cell active area. Good stability was observed during a approximate to 650 h steady-state test. Excellent stability was also observed over 20 redox cycles. (c) 2006 Elsevier B.V. All rights reserved.
This paper describes calculations of the electrical losses in patterned series-connected solid oxide fuel cells (SOFCs), i.e. the "segmented-in-series" configuration. Losses due to cell resistances, electrod...
详细信息
This paper describes calculations of the electrical losses in patterned series-connected solid oxide fuel cells (SOFCs), i.e. the "segmented-in-series" configuration. Losses due to cell resistances, electrode ohmic resistances, interconnect resistance, and shunting by a weakly-conductive support material were considered. For any given set of cell dimensions and characteristics, power density was maximized at an optimal cell length - the power decreased at larger cell lengths due to electrode lateral resistance loss and decreased at smaller cell lengths due to a decreasing fraction of cell active area. For cell lengths well above the optimal value, electrolyte current was often confined to the portion of the cell nearest to where the less conductive electrode (i.e. the cathode) connected to the interconnect. Assuming dimensions expected for screen printing, i.e. approximate to 20 mu m thick electrodes and lateral print accuracy of approximate to 100 mu m, and area specific resistance values typical of SOFCs, optimal cell lengths typically ranged from 1 to 3 turn. Shunting currents increased with decreasing cell lengths, but were found to have little effect on power density assuming partially-stabilized zirconia supports and temperatures <= 800 degrees C. (c) 2005 Elsevier B.V. All rights reserved.
暂无评论