Power Generation by Flat-Tube Solid Oxide Fuel Cells with Enhanced Internal Reforming of Methanol

Methanol is a promising fuel for solid oxide fuel cells (SOFCs) because of its low cost and ease of storage and transportation. In this work, the performance and long-term durability of direct methanol flat-tube SOFCs are investigated under different steam/carbon (S/C) ratios. It is confirmed that the S/C ratio exhibits little influence on cell performance but strongly affects long-term stability. The cell is discharged stably under high S/C ratios of 1.5 and 1.2, while it fails abruptly under a low S/C ratio of 1 due to severe carbon deposition. Extra nickel/yttria stabilized zirconia (Ni/YSZ) catalyst is added into the anode channels to serve as a prereformer. With improved internal reforming, the methanol conversion rate is promoted to 95% under S/C = 1, higher than that without extra catalyst and most results reported in the literature, and carbon deposition within the anode is significantly suppressed. Thus, no performance degradation is observed for 300 h of discharge under S/C = 1. On the basis of the experimental and simulating results, the mechanism of methanol conversion within the flat-tube cells is discussed.