Redox Stability of Tubular Solid Oxide Cell Using LaGaO₃Electrolyte Film Prepared by Dip-Coating

Reversible operation of SOFCs is an important subject in renewable energy and is urgently needed at present. A NiO-YSZ tubular cell using a La_0.9Sr_0.1Ga_0.8Mg_0.2O_3-δelectrolyte was prepared by dip-coating and its reversible operation was studied. Effects of Ce infiltration into the Ni-YSZ substrate was also studied and it was found that Ce infiltration is highly effective for increasing cell performance and stability in fuel cell and electrolysis modes. Cyclic operation of the LSGM tubular cell in SOEC and SOFC modes using a Ce infiltrated Ni-YSZ substrate was measured at 600 under 17%steam-25%H₂in Ar. During 100 redox cycles at 0.1 A cm^-2, the OCV remained almost unchanged from the initial value. The SOFC operating potential decreased slightly with increasing cycles, however, the degradation rate was significantly decreased by Ce infiltration.