本研究使用金屬發泡材為質子交換膜燃料電池之流場，金屬發泡材具有高孔隙率（85%以上）、質量輕之特性，相較於傳統流道具有較小的質傳效應且無肋條遮蔽效應。藉由改變三種不同金屬發泡材面密度（800 g/m2、1000 g/m2、1200 g/m2）及三種孔洞數（94 PPI、110 PPI、130 PPI），共九種不同規格之金屬發泡材。探討金屬發泡材面密度及孔洞大小對於燃料電池性能的影響，並量測電池性能、交流阻抗及24小時性能測試。在24小時性能測試時每三小時清除大部分水氣並量測其性能、以EIS分析質傳阻抗及分析波德圖中水的擾動。實驗結果顯示在50 ℃下，使用1200 g/m2•130PPI規格之金屬發泡材性能為最低，性能為1217 mA/cm2，使用800 g/m2•94PPI規格之金屬發泡材性能為最高，性能為1715 mA/cm2，性能相差41%之電池性能，在24小時性能測試結果下，在三種規格面密度下94 PPI金屬發泡材均具有較高的電池穩定性，並以800面密度為最好，此研究有助於未來發展具有低質傳阻抗、高性能和高穩定性之質子交換膜燃料電池。;In this research low weight and high porous metal foam is used as a flow channel in Proton Exchange Membrane Fuel Cell（PEMFC）to reduce the mass transfer resistance and no-shadowing effect. Three area densities（800 g/m2, 1000 g/m2, 1200 g/m2）of metal foam with three different pores per inch（94 PPI, 110 PPI, 130 PPI） are used in this study. The impact of metal foam area density and pore size on the performance of fuel cell is investigated in detail. Also, AC impedance and performance test for 24 hours is also studied. The water formed in the 24 hours cell operation of PEMFC is removed periodically for every 3 hours. Further, the electrochemical impedance spectroscopy and I-V curve are measured accordingly to understand the mass transfer characteristics and water distribution by bode plot. Results in this study show that at 50℃, the performance of using 1200 g/m2•130PPI metal foam is the lowest, the performance is 1217 mA/cm2（@ 0.6 V）, and the performance using 800 g/m2•94PPI metal foam is the highest, the performance is 1715 mA/cm2（@ 0.6 V）. A difference of 41 % in cell performance（@ 0.6 V）is observed by varying the density and porosity of metal foam. The 24 hours cell performance results shows that 94 PPI metal foam exhibits highest stability in three kinds PPI and an area density of 800 g/m2 has highest stability in three differents area density. The results of this study are helpful for researchers in future to develop PEMFC with low mass transfer resistance, high performance, and high stability.
