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The anode-supported solid oxide fuel cell (SOFC) comprises of NiO-8YSZ | 8YSZ | LSM-GDC | LSCF and the performance durability is executed for over 1000 hours. It shows low degradation phenomena under constant current operation during the complete testing period. The cell performance decreases with the decreasing of the temperature, and the maximum power densities are 408, 265, and 163 mW cm-2at 800, 750, and 700 °C, respectively. According to the EIS analysis with the equivalent circuit model of five serial components, all resistances decrease with the testing time except the non-charge transfer resistance of the cathode. However all resistances increase with the decreasing of the temperature on the contrary. The ohmic resistance of the cell (RO) dominates the cell performance under the whole durability test period as well as the operation temperature. In this study, the ROis determined by the interfacial contact resistances, which occurred between the cell and the connecting components. The LSM-GDC | LSCF interfaces formed the discontinuous gap due to the weak attachment and external loading. The result of the activation energy analysis shows that the rate-determination step of the cell is existed in the anode side between 700 and 800 °C. However, the cell performance is controlled from the domination of the ROat 800 °C shift to the joint contributions of the RO, anodic polarization (RAP), and cathodic polarization (RCP) at 700 °C.

Yttria-stabilized zirconia (YSZ) is the most commonly used electrolyte material for solid oxide fuel cells. The use of relatively inexpensive metal components would require a trade-off in the lowering of the operating temperature below 800 °C. However, the reduced temperature results in an increased resistivity of YSZ. This can be overcome by reducing the electrolyte thickness using thin film techniques. In this study, the preparation of a thin film of YSZ via the sputter deposition technique was reported. YSZ electrolyte films were deposited on anode substrates at 650/750 °C. The gas permeability test indicated a gas-tight electrolyte with a gas leak rate − 7 lcm − 2 s − 1 . The measured open circuit voltage was 1.1 V, while the maximum power density was 515 mW cm − 2 .

The anode-supported solid oxide fuel cell (SOFC) with low-porosity anode structure is fabricated and the electrochemical characteristics are investigated. The electrochemical characterization of the cell shows a periodic oscillation phenomenon of the cell voltage under the constant current density operation. The low-porosity anode structure results in the decrease in the effective diffusion coefficient and the accumulation of water vapor. The cell voltage oscillation is mainly caused by the concentration polarization as well as the boundary migration of the reaction zone. The profound influence on the concentration polarization can be observed when the cell test is executed with operation condition of higher current density, lower hydrogen concentration, and lower hydrogen flow rate in the anode side.