Performance and durability evaluation for anode-supported solid oxide fuel cell with Ce_(0.8)Sm_(0.2)O_(2-δ) - SmBa_(0.5)Sr_(0.5)Co_2O_(5+δ) composite cathodes

摘要

We synthesize the SmBa_(0.5)Sr_(0.5)Co_2O_(5+δ) (SBSC) powders by glycine nitrate combustion method and then design the composite cathodes by mixing with Sm_0._2Ce_(0.8)O_(2-δ) (SDC) for thermal expansion mismatch concern. The cell exhibits good adhesion between layers to improve cell performance. The cell with yittria-stabilized zirconia (YSZ) electrolyte via cathode design of SDC | SDC-SBSC, is operated from 600 to 800°C. The power densities for operation potential 0.7 V shows the acceptable value of 498 mWcm~(-2) at 800°C. To evaluate the durability, it is operated under fixed current density over thousand hours. A slight degradation in the activation region can be observed at the initial stage. The degradation rate is estimated at less than 0.5%/khr after activation with current loading. The operational conditions with lower current loading and higher operation potential are the solution to prolong the cell life time. Further demonstration for IT-SOFC cell product shall be executed.