International Journal of Hydrogen Energy, Vol.38, No.36, 16300-16307, 2013
Galliosilicate glasses for viscous sealants in solid oxide fuel cell stacks: Part I: Compositional design
Galliosilicate glasses were developed for sealing intermediate temperature planar solid oxide fuel cell (SOFC) stacks. Candidate sealing glasses were identified for use at operating temperatures of 750 degrees C and at 850 degrees C after assessing flow behavior, thermal expansion properties, and crystallization behavior. A series of non-alkali glasses was identified for use at 750 degrees C within a strontium boro-galliosilicate compositional region that exhibited glass transition temperatures (T-g) between 658 and 675 degrees C and coefficients of thermal expansion (CTE) between 8 and 9.4 x 10(-6) K-1. Glass fits and powders flowed below 850 degrees C and did not crystallize dramatically after 500 h at 750 C. Several glasses containing 5 mol% mixed alkali were identified in a strontium boro-galliosilicate compositional region for use at 850 degrees C. The glasses exhibited T-g between 615 and 620 degrees C with CTE from 7.8 to 9.7 x 10(-6) K-1. Glass fits flowed well below 850 degrees C and retained remnant glass phase after partial crystallization at 850 degrees C. The galliosilicate glasses developed in this work enable viscous sealing of SOFC stacks. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Solid oxide fuel cell;Sealing glass;Galliosilicate;Viscosity;Thermal expansion;Crystallization