純氫氣配合低溫型質子交換膜燃料電池使用，有較佳使用效率和便利性，且降低白金觸媒被毒化的機率。本研究之目的在於利用低壓型之儲氫材料配合商用白金碳布電極組裝的燃料電池，量測氫氣的轉換效率。此外，本實驗另一個重點為利用高孔性的海綿鎳取代傳統石墨導流槽組裝小型單電池，藉此了解氫氣流道對燃料電池放電特性之影響，並進一步探討電極面積和氫氣轉換效率之間的關係。
本實驗首先對低壓型儲氫材料的特性進行瞭解，並自製小型儲氫管作為燃料電池的氫氣供應源﹔同時，藉由自組放電裝置測量燃料電池最佳之放電條件，並用循環伏安法和交流阻抗驗證之。之後使用儲氫管中之氫氣在不同流量下測量燃料電池氫氣轉換效率。

實驗結果發現，E-TEK商用電極 (觸媒含量0.4 g Pt/cm2)在電池溫度為800C有最佳的放電曲線﹔雖然氫氣轉換效率在氫流量化學計量比為1時轉換效率高但電流卻不穩定。電池溫度為600C時，氫流量化學計量比為1.5時有較穩定的電流，但氫氣轉化效率較前者為低。另外，由高孔性海綿鎳組成的電池組，其放電效率低於傳統的電池組，可能是氣體導流槽未能將氣體均勻分布於反應位置，或是海綿鎳未經疏水處理。此外，測試不同電極面積組成的電池組，發現控制陰極面積可以得到較佳的放電性能。

Hydrogen gas is considered as a good candidate fuel for the proton exchange membrane fuel cell (PEMFC) due to its convenience in the system design and its high efficiency of energy transfer. Besides, pure hydrogen can prevent the platinum catalyst from poisoning by carbon monoxide below 1000C. In this study, a homemade copper hydrogen storage tube using a commercial metal hydride Hsu-Yang T1 was used as the fuel to study the hydrogen transfer efficiency in the PEMFC. A new cell setup using Ni foam as the gas flow channel was also designed to study the cell performance.
The P-C-T curves were established and were used to provide basic properties of the metal hydrides. Meanwhile, a fuel cell test station and several single cell setups were fabricated to study the optimum operation condition of the fuel cells. The characteristics of the fuel cell were correlated with the results of AC impedance and cyclic voltammetry. Hydrogen storage tube was installed to the fuel cell test system to study the hydrogen transfer efficiency at different hydrogen flow rates.

It was found that the E-TEK electrode had higher cell performance than the Toray electrode, and the E-TEK electrode had better discharge performance at 800C than other lower temperatures. A high hydrogen transfer efficiency but unstable currents were obtained. Stable currents but lower hydrogen transfer efficiency could be observed at 600C. With Ni foam replacing for the graphite gas flow channel, the discharge performance was slightly inferior to that of the traditional design. The cell performance was enhanced when the cathode areas were increased presumably due to the increased reaction cross-section of oxygen and the protons.

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