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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]

The possibility of eliminating finger or vermicular growth of α-Al2O3 particles obtained by calcination of boehmite was examined. Heterogeneous precipitation of boehmite in a well-dispersed θ-Al2O3 suspension was first prepared, in which the mass ratio of boehmite to θ-crystallite was evaluated to form agglomerates of similar sizes that will form α-Al2O3 crystallites of <100 nm in diameter. θ- to α-phase transformation of alumina experiences a nucleation and growth mechanism, with the critical size of nucleation being ∼25 nm for θ-Al2O3 and the size for accomplishment of transformation followed by finger growth being ∼100 nm. Hence, fabricating agglomerates that would form α-Al2O3 crystallites with sizes <100 nm accompanied with appropriate thermal treatments can be a method for obtaining α-Al2O3 crystallites free of finger growth. It is found that proper preparation of the agglomerate with appropriate size may initiate a simultaneous and lower temperature θ- to α-Al2O3 phase transformation for such powder systems, substantially limiting the mass transfer among the newly formed α-Al2O3 particles. Moreover, α-Al2O3 crystallites free of finger growth can be obtained. [ABSTRACT FROM AUTHOR]