PNNL

Abstract

A novel refractory alkaline-earth silicate (Sr-Ca-Y-B-Si) sealing glass was developed for solid oxide fuel cell (SOFC) applications. The glass was sealed between two metallic interconnect plates and tested for electrical stability at elevated temperatures and duel environments under DC loading. The isothermal aging results showed very stable electrical resistivity with values 5-9 orders of magnititudes higher than typical SOFC function materials at 850 degrees C for ~700 hr. For comparison, the state-of-the-art sealing glass (G18, Ba-Ca-Al-B-Si) was also evaluated in a similar condition and showed less stable in accelerated tests at 830 degrees C for ~100 hr. Interfacial microstruicture was characterized and possible reactions were discussed.