Effect of thermal cycling on durability of a solid oxide fuel cell stack with external manifold structure

摘要

A 5-cell stack with external manifold is thermal cycled between room temperature and 750 degrees C fifteen times. The electric performances after each cycle are measured and compared. The stack has an initial peak output of 328.44 W and shows excellent stability in thermal cycling. The average operating voltage degradation rate is only 0.8% corresponding each thermal cycle. A cell from the stack is randomly chosen for electrochemical evaluation. Its performance is found to be comparable to a cell which is not thermal cycled. Post-test examination shows deterioration of cathode contact materials at points of contact and cracks throughout the oxide layer between corrugated and bipolar plates to be the main causes of the degradation. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.