為將陽極端流道減薄，本研究使用不同規格金屬發泡材，探討其孔洞數與厚度對其孔徑、孔隙率、滲透率與電阻值之影響，並應用於高溫型質子交換膜燃料電池，且將薄化之最佳結果與實驗室原設計進行比較，以及探討操作溫度、加濕溫度、氣體背壓與空氣當量比等參數對電池性能之影響。
研究結果顯示，在金屬發泡材物理特性分析中，能使用雷諾數與摩擦因子之關係建立不同規格金屬發泡材之氣體擴散性。在燃料電池研究上，當流量固定時，厚度減薄會使氣體流速變快，故使用滲透率較低之發泡材能有效薄化流道並維持電池性能，而本研究成功建立發泡材之穆迪圖與電池性能及交流阻抗分析之結果相符。與原設計相比，最佳條件之設計可將陽極端減薄30.8 %與單電池總重量減少20 %，在0.6 V之性能提升11.5 %。操作參數之結果顯示，增加溫度、背壓與空氣當量比皆能提升電池性能，唯有加濕對電池性能影響不大。

In order to reduce the thickness and weight of the metallic flow distributor plate, the effects of channel depth, pore size and thickness of metal foam are investigated. Relation between pore size, thickness and the permeability and electrical resistance of the metal foam were first established. Then, these metal foams were applied to high temperature proton exchange membrane fuel cell. The performance of new design were compared with previous design. Moreover, effects of cell temperature, humidification, back pressure and air stoichiometry were also studied.
The results of fuel cells show that the lower permeability of metal foam was favorable for the thinner flow channel. The reason is that, for fixed flow rate, gas velocity is increased with the thinner flow channel and lower permeability increases the probability of gas moving into the reactive area. The fuel cell performance agrees well with the electrochemical impedance results. Compared with previous design, the optimized design reduces 20 % cell weight, while increasing 11.5 % cell performance at 0.6 V. Results also show that increasing temperature, back pressure and air stoichiometry improves the cell performance. However, the degree of humidification does not substantially affect cell performance.

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