固体氧化物燃料电池玻璃态封接材料

Investigation on a glass sealant for intermediate temperature solid oxide fuel cells

平板式中温固体氧化物燃料电池在500￣850℃下运行,电解质两侧的工作气体(阳极气室的燃料和阴极气室的空气)必须彻底隔离,因此电池部件间气密封接至关重要。该工作是在制备出的SiO2-B2O3-Al2O3-BaO-PbO2-ZnO玻璃体系密封材料基础上,优选出性能最佳的配方(AF8)。通过对AF8进行了热膨胀曲线的测试,计算材料的软化点和高温粘度;观测结果表明,材料在YSZ浸润角测试、附着性和气密性的观测,利用交流阻抗谱测试材料的高温电阻率在105!·cm以上。以此密封材料封装的单电池开路电压接近理论值,在经历3次快速热循环时电压也没有衰退。因此,AF8是一种能够提供“软”密封的材料,而且工作中的粘滞流动性很好的满足了应力释放要求。

Intermediate temperature plate type solid oxide fuel cells （ IT-pSOFC ） are operated at 500-850℃, and the working gases between two sides of electrolyte, etc, fuel in anode chamber and air in cathode chamber, must be separated drastically, so a hermetical seal between components is essential. In this paper, a glass system based on SiO2-B2O3-Al2O3-BaO-PbO2-ZnO was prepared and the contents were optimized to determine the best material named AF 8. The soften point and viscosity at high temperature were calculated based on the result of thermal expansion curve. The contact angel, adherence and gas tight performance were also observed. The resistivity of AF 8 measured by AC impedance spectroscopy was over 10^5Ω·cm. The open circuit voltage of single cell sealed with this sealant was near theory value and there was no degradation after 3 quick thermal cycles So AF 8 is such a material that can meet the viscosity and stress relaxation during preoaration and operation.