Study of Geometric Stability and Structural Integrity of Self-Healing Glass Seal System Used in Solid Oxide Fuel Cells

Journal Article · Tue Feb 15 00:00:00 EST 2011 · Journal of Power Sources, 196(4):1750-1761

DOI:https://doi.org/10.1016/j.jpowsour.2010.10.002· OSTI ID:1222168

Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.

A self-healing glass seal has the potential of restoring its mechanical properties upon being reheated to SOFC stack operating temperature, even when it has experienced some cooling induced damage/cracking at room temperature. Such a self-healing feature is desirable for achieving high seal reliability during thermal cycling. On the other hand, self-healing glass is also characterized by its low mechanical stiffness and high creep rate at the typical operating temperature of SOFCs. Therefore, geometry stability and structural integrity of the glass seal system becomes critical to its successful application in SOFCs. In this paper, the geometry stability of the self-healing glass and the influence of various interfacial conditions of ceramic stoppers with the PEN, IC, and glass seal on the structural integrity of the glass seal during the operating and cooling down processes are studied using finite element analyses. For this purpose, the test cell used in the leakage tests for compliant glass seals conducted at PNNL is taken as the initial modeling geometry. The effect of the ceramic stopper on the geometry stability of the self-healing glass sealants is studied first. Two interfacial conditions of the ceramic stopper and glass seals, i.e., bonded (strong) or un-bonded (weak), are considered. Then the influences of interfacial strengths at various interfaces, i.e., stopper/glass, stopper/PEN, as well as stopper/IC plate, on the geometry stability and reliability of glass during the operating and cooling processes are examined.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1222168
• Report Number(s): PNNL-SA-73404; AA6040000
• Journal Information: Journal of Power Sources, 196(4):1750-1761, Journal Name: Journal of Power Sources, 196(4):1750-1761
• Country of Publication: United States
• Language: English

Related Subjects

self-healing
glass
SOFC
geometry stability
structure integrity