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The electrochemical properties and long-term performance of an in-situ composite cathode comprised of SmBa 0.5 Sr 0.5 Co 2 O 5+δ (SBSCO) and Ce 0.9 Gd 0.1 O 2−δ (CGO91) are investigated for metal supported solid oxide fuel cell (MS-SOFC) application. The Area Specific Resistance (ASR) of an in-situ composite cathode comprised of 50 wt% of SBSCO and 50 wt% of CGO91 (SBSCO:50) is 0.031 Ω cm 2 in the first stage of measurement at 700 °C; this value of ASR increases to 0.138 Ω cm 2 after 1000 h. The ASR of SBSCO:50 (in-situ sample at 750 °C) is 0.014 Ω cm 2 at the initial stage of measurement; the increase of ASR after 1000 h at 750 °C is only 0.067 Ω cm 2 . These results suggest that the optimum temperature for in-situ firing of an SBSCO:50 cathode sample of MS-SOFC is higher than 700 °C, ideally around 750 °C. [ABSTRACT FROM AUTHOR]

Abstract: Using relatively simple and cheap joining process, anode-supported solid oxide fuel cell integrated with metal interconnect is fabricated and its impedance spectra are analyzed and compared with anode-supported cell at the operating temperature of 800°C. The stable long-term performance is shown for about 800h at 800°C under the constant current density of 300mAcm−2. The thermal cycle experiments from the operating temperature to the room temperature are also carried out in this study, while the maximum power density of 0.7Wcm−2 is indicated. The microstructures are analyzed using scanning electron microscope and energy dispersive X-ray spectra are analyzed for observing a diffusion of metal ions at the anode, adhesion layer and metal support. The diffusions of Fe and Cr from the adhesion layer to the inside of the anode occur during the operation and/or fabrication process, in which the diffused amount of Fe exceeds the value of Cr. It is considered that the undesired diffusions of Fe and Cr into the anode layer may cause the electrode degradation, but the anodic polarization decreases as the cell operation continues. [Copyright &y& Elsevier]

In-situ Ni and ex-situ NiO(Li) cathodes were fabricated by cold pressing using Ni powder and LiCO (in case of exsitu cathode) with paraffin wax as a binder. The effects of compaction pressure, amount of binder, and sintering temperature on porosity, the average size of pore, Li cation fraction, and the fracture strength were investigated in this study. The optimum compaction pressure was 100 kg/cm to prevent the brittleness and stress concentration caused by high compaction pressure. Also, 10 wt% of binder yielded best results and the strength decreased dramatically and revealed nonuniform pore and pore distribution beyond 10 wt%. To obtain reasonably high electric conductivity in exsitu cathode, the sintering temperature was chosen to be below 950°C to maintain the ration fraction of Li* is in the range of 0.02-0.06. In terms of the Ni-dissolution rate, exsitu cathode was more efficient than insitu cathode in the long-term operation except the initial 24hr period. [ABSTRACT FROM AUTHOR]