LSCM-(YSZ-CGO) composites as improved symmetrical electrodes for solid oxide fuel cells

摘要

A new concept of solid oxide fuel cell (SOFC), recently proposed, using simultaneously the same material (La_(0.75)Sr_(0.25)Cr_(0.5)5Mn_(0.5)O_(3-delta), LSCM), as both, anode and cathode, has been verified. The performance of such new design, symmetrical fuel cells (SFCs), could be improved by using a YSZ/CGO-based composite. The optimum ratio to minimise the series and the polarisation resistances (R_p) under reducing conductions was 1:1. This composition renders improved R_p values by a factor of 2 at 950 deg C in flowing H_2 in comparison to LSCM-YSZ composites. Thus, the use of a mixed composite (YSZ-CGO) will allow to extend the applicability of LSCM at temperatures lower than 850 deg C. LSCM-(YSZ-CGO) based SFCs offer promising performances, e.g., 0.4 W cm~(-2) at 950 deg C using humidified H_2 as fuel.