Long-term evolution of mechanical performance of solid oxide fuel cell stack and the underlying mechanism. (9th July 2021)

• Record Type: Journal Article
• Authors: Guo, Meiting; Lin, Zijing
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 47(2021)
• Page Start: 24293
• Page End: 24304
• Publication Date: 2021-07-09
• Subjects: Solid oxide fuel cell -- Thermal stress -- Failure probability -- Creep strain -- Thermal-mechanical evolution; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2021.04.196
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Mechanical performance analysis is important for ensuring the long-term reliability of solid oxide fuel cells (SOFCs). Thermal-mechanical models are constructed to conduct time-dependent mechanical performance analysis of SOFC stack with temperature field obtained by multiphysics modeling. The volume-averaged temperature field is used as comparison. The creep strains are examined with a time step of 10 h for 10, 000 h. It reveals: (1) Uniform temperature significantly decreases the stresses, strains, failure probabilities of all stack components. (2) The failure probability of sealant reduced rapidly and the sealant becomes mechanically safer for long-term operation. (3) Creep strain is dominant for anode/sealant/interconnect, but negligible for electrolyte/cathode. All components are predictably safe against strain failure for 100, 000 h (4) Creep strains of stack components interact with each other. Coupled analysis of creep strains of anode/sealant/interconnect is mandatory, but the creep strains of electrolyte/cathode may be neglected for studying mechanical evolutions. Highlights: In-depth analysis of thermal-mechanical evolutions of stack components during 10, 000 h. Creep strain as the mechanism for long-term safety of sealant clearly demonstrated. Close coupling of creeps and stress relaxations of different components revealed. Strong effect of temperature field on stress/strain and their evolutions illustrated.