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Nickel was added to anode substrates composed of porous YSZ, in order to minimize anode damage during redox cycling in SOFCs with a YSZ electrolyte. In this study, the electrical insulating and thermal properties of these materials were evaluated for their suitability as SOFC substrates.

Sr1-xLaxTiO3-δ perovskites are strong candidates for use as the anode and interconnect materials in solid oxide fuel cells. The thermal expansion properties of these materials with La contents of 0

The biggest SOFC R&D activities in China are conducted at NIMTE where 45 full time staffs are vertically integrated. We manufacture and sale planar anode supported cells for international market with the highest performance/price ratio. We offer various nano-powders including LSM, LSCF, LSC, CGO, YSZ and SSZ. Long term tests on performance degradation, in particular at low temperature and high current density, are intensively carried out in our cell testing group. We demonstrated low cost stack by combining internal manifolding design and low cost components selection. A five cell short stack has run for more than 3000 hours and the voltage is monitored individually. Stacks of 500W to kW power range are built and tested. We successfully manufactured 30×30cm2 cells for multi-kilowatt single stack. 2kW power and heat co-generation system are under development and 20kW electrical generation system are planned this year in collaboration with a big Chinese electricity generation company.

The sintering characteristics of Ce0.9Gd0.1O1.95 (CGO) with various specific surface areas and Zr0.89Sc0.1Ce0.01O1.95 (ScSZ) content have been measured. Cobalt-doped CGO can be used as a buffer layer on a ScSZ electrolyte for anode-supported solid oxide fuel cells with intermediate-temperature operation. By addition of ScSZ, the densifications of all CGO samples were markedly lowered. The Co-doping of CGO enhanced its densification and improved the increase of densification with increasing specific surface area.

We report a two-cell stack test of honeycomb SOFCs with air preheating channels. The honeycomb was made of 3YSZ with 3×3 channels. The size of each channel was 5×5 mm and the thickness of channel walls was 1 mm. Electrode materials were Ni(60 wt%)/8YSZ and La0.7Sr0.3MnO3. The OCV of 2.19 V was obtained at 800 ºC. Ag plates were used for the gas sealing and the interconnection between the honeycomb unit cells. The high value of OCV and the stable current during the experiment indicates a good gas sealing and small leak currents. After the measurement, the stack was cooled to room temperature, and held for 10 days, then it was heated again to 800 ºC. A small amount of OCV reduction was observed, however, no reduction was observed in the maximum power density. This successful test indicates that the interconnection using Ag plates is promising for honeycomb SOFC stacks.

Metal-supported SOFCs potentially offer many advantages compared to conventional technology, such as low operating temperatures, reduced cost, and increased reliability. They are also a promising choice for applications that require quick start-up, good stability against thermal cycles and mechanical shock resistance such as Auxiliary Power Units (APU) for the automotive industry. The National Research Council of Canada's Institute for Fuel Cell Innovation (NRC-IFCI) has been working on the development of metal supported SOFCs since 2004. In this paper, a metal-supported SOFC with a samarium doped ceria (SDC)/scandia-stabilized zirconia (ScSZ) bilayer electrolyte was fabricated by a combination of pulsed laser deposition (PLD) and wet chemistry processing. The cell performance and aging characteristics were analyzed by AC impedance spectroscopy and current-voltage measurements during operation in the temperature range from 400oC to 600oC. The power generation characteristics at low temperatures of this metal- supported SOFC will be beneficial for quick start-up and is expected to alleviate the performance deterioration. These results at such an early stage of research is very promising for the future development of this technology.

Solid oxide fuel cell (SOFC) is expected to be a candidate for distributed power sources in the next generation, due to its high efficiency, high-temperature waste heat utilization and low emission of pollutants to the environment. A number of models for planar SOFCs have been constructed, and co-flow, counter-flow and cross-flow simulations have been reported. In many cases, the variations of temperature in the cells are relatively large, so that the stresses in the cells increase and cell may be destroyed. In this study, we pay attention to the honeycomb SOFC having air preheating paths. One-dimensional model was constructed and preliminary temperature distribution analysis was done. It was observed that the increase in temperature could be reduced. Furthermore, the unified temperature distribution could be expected.

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Sr 1-x La x TiO 3 perovskites are strong candidate materials for the interconnects and anodes in solid oxide fuel cells. In this paper, the thermal expansion mechanism of Sr 1-x La x TiO 3 with La content of 0 ≤ x ≤ 0.3 during reduction-oxidation (redox) cycling is discussed. It was found that for La-doped SrTiO 3 , air-sintered samples shrank during cycling in the reducing atmosphere. On the other hand, the reduced Sr 1-x La x TiO 3 samples expanded during cycling in air. This thermal expansion behavior is considered to be related to the formation and disappearance of Sr vacancies in the perovskites through the release and absorption of oxygen, respectively.

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An anode-supported solid oxide fuel cell (SOFC) with lanthanum-doped ceria (LDC) and strontium and magnesium doped lanthanum gallate (LSGM) bilayer electrolytes was fabricated and tested. The bilayer electrolyte thin film, consisting of a 25 mum thick LDC layer and a 75 mum thick LSGM layer, was prepared by a simple dry-pressing process. The two electrolyte layers were sintered together well, and no crack and peel-off at the interface were observed. An open-circuit potential of 1.02 V and a maximum power density of over 1.1 W/cm(2) was achieved with H-2 as fuel and air as oxidant at 800degreesC. The results show that the reactions between LSGM and anode materials were restrained by the LDC electrolyte layer, whereas the electronic conductivity of ceria-based electrolyte was blocked by the LSGM electrolyte layer. (C)2004 The Electrochemical Society.