Degradation Evaluation of LaCrO3-Based Interconnect on the Basis of Oxygen Permeation Measurements

Abstract

Degradation of LaCrO3-based interconnect was evaluated by comparing the oxygen permeation flux for flat tube SOFC cells before and after long-term operation (20,000 hours). Oxygen permeation flux was estimated based on the amount of water vapor, which was generated as a result of oxygen permeation from the air side to the hydrogen side. The estimated oxygen permeation flux for the SOFC cell before long-term operation was found to be in the range of 0.02–0.06 mL cm−2 min−1 at 750 °C. For the cell after long-term operation, the oxygen permeation flux was found to be in the range of 0.04–0.05 mL cm−2 min−1, which was almost similar with that for the cell before long-term operation. This suggested that degradation of LaCrO3-based interconnect, i.e., increase in oxygen permeation flux, is quite small.