Oxygen Permeation Measurement of LaCrO3-based Interconnect Embedded in Real SOFCs

Abstract

A method for evaluating the oxygen permeation flux through LaCrO3-based interconnects embedded in real solid oxide fuel cells (SOFCs) is proposed. The interconnect of the cell was placed in a two-chamber setup (fuel | interconnect | air), and the oxygen permeation flux was successfully determined by quantifying the amount of water vapor generated at the fuel side due to the permeation of oxygen from the air side to the fuel side. Using the proposed method, the oxygen permeation fluxes through the interconnects of the cells before and after 20,000 h of continuous operation were compared to examine the long-term stability of the LaCrO3-based interconnects. No significant difference was observed in the oxygen permeation flux before and after continuous operation, indicating that the LaCrO3-based interconnects have excellent chemical and thermal stability. In addition, the effect of oxygen permeation on energy conversion efficiency was investigated by calculating the Nernst loss. The calculations showed that oxygen permeation has almost no effect on the energy conversion efficiency.