Co-Firing of Anode-Supported SOFCs with Thin La[sub 0.9]Sr[sub 0.1]Ga[sub 0.8]Mg[sub 0.2]O[sub 3−δ] Electrolytes

Anode-supported solid oxide fuel cells (SOFCs) with thin (LSGM) electrolytes and (LDC) barrier layers were studied. The cells were fabricated by first colloidally depositing an LDC/LSGM/LDC tri-layer on a NiO-LDC anode support and co-firing. Cathodes consisting of LSCF-LSGM were then deposited and fired. Cell tests in air and humidified hydrogen showed maximum power densities of at and at . The relatively good performance indicated that the LDC layers were effective in minimizing interdiffusion and reaction. However, the open-circuit voltage of these cells was lower than the Nernst potential; observations of electrolyte microstructure and composition indicated that this was due to electronic conductivity in the LSGM layer, resulting from Ni impurities that entered during co-firing with the NiO-LDC anode. While the LDC layers were necessary, impedance measurements indicated that they substantially increased the cell ohmic resistance.