High-performance cathode-supported SOFC with perovskite anode operating in weakly humidified hydrogen and methane

Abstract

A high-performance, cathode-supported solid oxide fuel cell (SOFC), suitable for operating in weakly humidified hydrogen and methane, has been developed. The SOFC is essentially made up of a YSZ–LSM composite supporting cathode, a thin YSZ film electrolyte, and a GDC-impregnated La0.75Sr0.25Cr0.5Mn0.5O3 (LSCM) anode. A gas-tight thin YSZ film (27 μm) was formed during the co-sintering of the cathode/electrolyte bilayer at 1200°C. The cathode-supported SOFC developed in this study showed encouraging performance with maximum power density of 0.182, 0.419, 0.628 and 0.818 W/cm2 in air/3% H2O–97% H2 (and 0.06, 0.158, 0.221 and 0.352 W/cm2 in air/3% H2O–97% CH4) at 750, 800, 850 and 900°C, respectively. Such performance is close to that of the cathode-supported cell (0.42 W/cm2 versus 0.455 W/cm2 in humidified H2 at 800°C) developed by Yamahara et al.[1] [DOI: 10.1016/j.ssi.2004.09.023] with a Co-infiltrated supporting LSM-YSZ cathode, an (Sc2O3)0.1(Y2O3)0.01(ZrO2)0.89 (SYSZ) electrolyte of 15 μm thickness and an SYSZ/Ni anode, indicating that the performance of the GDC-impregnated LSCM anode is comparable to that made of Ni cermet while stable in weakly humidified methane fuel.