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This paper presents the work on the improvement of modified current collector in a fuel cell testing device with a solid oxide fuel cell (SOFC) consisting of a NiO-YSZ anode as the cell substrate, an 8 µm thick YSZ electrolyte, a screen-printed LSM cathode, and a Pt current collector. The cell exhibits gas-tight structure and the electrode layers are well adhered to the electrolyte. The effects of the current collector setup, operation temperature, and feed flow rates of air and hydrogen on cell performance are investigated. The experimental results demonstrate that the modification of a current collector setup can efficiently improve the contact between the current collector and the electrode, so as to elevate the measurement reliability for the performance data. The maximum output power density (Pmax) reaches 206 mW/cm² for the temperature of 800 °C via the modified current collection setup. Compare to the cell without current collection treatment, the power density increases to three times of the measured values. This patented testing apparatus can thus enhance the cell testing reliability and provides identical measurement accuracy. [ABSTRACT FROM AUTHOR]

An anode-supported solid oxide fuel cell consisting of a NiO-YSZ anode, YSZ electrolyte, and GDC-LSM ∣∣ LSM composite cathodes has been investigated. The cell is fabricated with a 10 × 10 cm2 commercially available size and has been electrochemically tested. The thicknesses of YSZ, GDC-LSM, and LSM layers are 5, 14, and 40 m, respectively. From the energy dispersive X-ray (EDX) result, this cell exhibits the excellent chemical stability among YSZ, GDC and LSM. The open circuit voltage is greater than 1.0 V at 800 °C, suggesting a firm cell structure. The power densities are 90, 156, and 257 mW cm-2 at 700, 750, and 800 °C, respectively. The durability evaluation is executed for 1,400 hours with some thermal cycles. According to the results of the electrochemical test and electrochemical impedance spectroscopy (EIS), the electrochemical performance of cell is dominated by the electrode polarization resistance (RP). During the activation process, the value of RP apparently decreases from 1.86 to 1.60 cm2. However, the electrode polarization resistance increases due to the degradation of electrochemical performance of SOFC-MEA. The values of RE (ohmic resistance) and RP are 0.24 and 5.92, 0.33 and 3.37, as well as 0.20 and 2.07 Ωcm2 at 700, 750, and 800 °C, respectively. The power densities at 0.6 V are 90, 156, and 257 mW/cm2 for the temperatures of 700, 750, and 800 °C, respectively. Essentially, the electrochemical performance of the anode supported cell nearly achieves the international level. The operational conditions with lower current density or higher cell voltage can prolong the cell lifetime but decrease the lower output power, thus decreasing the degradation rate upon practical operation. [ABSTRACT FROM AUTHOR]

The layered samarium and strontium doped perovskite oxide SmBa0.5Sr0.5Co2O5+δ (SBSC) is synthesized by glycine nitrate combustion process. The crystallinity of SBSC powder with calcination temperatures shows that the perovskite phase is completely formed above 1000 °C. SBSC powders mixed with Sm0.2Ce0.8O2-δ (SDC) have been utilized as cathode materials to form a composite cathode which provides better compatibility with electrolyte and enhances the catalytic property for the cell. The single cell of yittria-stabilized zirconia (YSZ) based electrolyte with structure of NiO-YSZ | YSZ | SDC | SDC-SBSC, is operated from 700 to 800 °C with H2 as a fuel and ambient air as oxidant. The maximum power densities are 603, 449 and 321 mW cm-2 at 800, 750 and 700 °C, respectively. According to the electrochemical impedance spectroscopy, the charge-transfer resistances of the electrodes are 0.10, 0.14, and 0.27Ωcm2, and the non-charge-transfer resistances are 0.87, 0.97, and 1.09 Ωcm2 at 800, 750, and 700 °C, respectively. The experimental results indicate that SBSC is a promising cathode material for intermediate temperature solid oxide fuel cell (IT-SOFC). [ABSTRACT FROM AUTHOR]

The anode-supported solid oxide fuel cells (SOFCs) with an yttria-stabilized zirconia (YSZ) electrolyte have been successfully prepared by the sequential steps of fabricating technique including tape casting, spin coating, and screen-printing. Two types of the SOFCs are manufactured and their cell performances are characterized via the detail analysis of the electrochemical impedance spectroscopy (EIS). The maximum power densities are 411 and 289 mW/cm2 for the high and low performance cells at 800°C, respectively. According to the EIS analysis, the electrochemical performance of the poor cell is dominated by the anodic non-charge-transfer resistance, which is mainly resulted by the gas diffusion polarization due to the low porosity of the anode. The high performance cell is controlled by the simultaneous contributions of the ohmic resistance (RO), the anodic polarization (RAP), and the cathodic polarization (RCP) at the operation temperature of 800°C. However, the RCP will dominate the performance of the cell as the temperature is lowered down to 700°C. [ABSTRACT FROM AUTHOR]

Yttria-stabilized zirconia (YSZ) is the key material for an electrolyte of a solid oxide fuel cell (SOFC). In order to prepare a nanoscale/SOFC-grade 8YSZ material, the hydrothermal coprecipitation process is intensively investigated for process improvement and product identification. From the characterization results of the 8YSZ product, the operation conditions were selected for process optimization. The criteria used in optimization condition determination were the reproducibility of the 8YSZ product and the particle size, the crystallinity, as well as the operation simplicity. Experimental results showed that a nanoscale/SOFC-grade 8YSZ powder was directly prepared. The quasi-optimum conditions of the process are proposed. [ABSTRACT FROM AUTHOR]

The article explores the development of solid oxide fuel cell (SOFC) at the Institute of Nuclear Energy Research (INER) in Taiwan. The goal of the INER SOFC project is to establish the technologies and equipment for the fabrication of cell, stack and demonstrative system. It is concluded that Taiwan lacks the supply of indigenous energy, but the SOFC system is considered as a potential technology to promote energy security, environmental protection and economic growth