Synthesis and long-term test of borosilicate-based sealing glass for solid oxide fuel cells

• Published in: Journal of the European Ceramic Society Vol. 31; no. 11; pp. 1975 - 1985
• Main Authors: Lin, Sung-En, Cheng, Yi-Ru, Wei, W.C.J.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-10-2011
• Subjects: Borate; Forming; Fuel cells; Glass; Interface reactions; Leakage; Sealing; Sealing materials; Silicate; Solid oxide fuel cells; Thermal expansion; Silicate; Borate; Fuel cells; Glass
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2011.04.017

A series of borosilicate-based glasses, ternary BaO–SiO
2–B
2O
3 and quaternary BaO–SiO
2–B
2O
3–Al
2O
3 systems, are prepared as sealing materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). The thermal expansion, crystalline phases, glass forming ability, and thermo-chemical stabilities of the glasses are characterized. Additionally, the effect of the B
2O
3/SiO
2 ratio and Al
2O
3 and BaO contents on the coefficient of thermal expansion (CTE) are discussed and compared. Test results show that one glass (G6) can fully wet various substrates at the sealing temperature of 1000
°C and match thermal expansion. Possible interfacial reactions between the glass and those cell components aging up to 5000
h are investigated by element mapping, XRD, SEM, and EPMA. Leakage testing was also performed at temperatures up to 650
°C. The results show that the glass (G6) remains amorphous after 5000
h test and is stable under these conditions and compatible with the other fuel cell components.