質子交換膜燃料電池之傳輸現象及最佳化設計研究

Study of Transport Phenomena and Optimal Design for Proton Exchange Membrane Fuel Cells

許泓錡(Hung-Chi Hsu)

指導教授 ： 鄭金祥

大同大學/工程學院/機械工程學系所/碩士(2004年)

摘要

本研究主要探討質子交換膜燃料電池內部之傳輸現象與最佳參數分析，研究不同組件之電導率、孔隙率、厚度、與流道開口比的影響，並利用數值方法模擬二維陰極半電池之傳輸現象並據以決定最佳的參數設計。
研究中發現，電導率的影響以氣體擴散層最為明顯，選擇電導率較高的氣體擴散層材料會有效的提升電池性能。流道開口比λ的大小也會影響電池之性能，由結果得知，最佳之開口比例λ為0.65，此時的電池性能最佳。孔隙率的影響不僅是濃度擴散的效應，對有效電導率也會有所影響，由結果得知氣體擴散層之最佳孔隙率為0.6，而觸媒層之最佳孔隙率為0.5。在厚度方面，氣體擴散層的厚度愈薄會對整體的電池性能提升較多，觸媒層由於厚度比較薄，增加其厚度對提升電池的性能反而較不明顯。

關鍵字

質子交換膜燃料電池、電導率、流道開口比、孔隙率

並列摘要

The study is concerned with the transport phenomenon in a proton exchange membrane fuel cells(PEMFC) and the optimal parameter analysis。The research focus on the influences of different conductivities、channel ratioλ=lc/lb、porosity and thickness， numerical method is utilized to simulate the transport phenomenon in a 2-D half-cell model to obtain optimal parameters。
The results reveal that the GDL is most important for the influences of conductivity，so we can raise the cell performance effectively by choosing high conductivity of GDL materials。Channel ratioλ would also affect the cell performance，by the results，the optimal channel ratioλis 0.65 and reach a optimal performance。The influences of the porosity is not only the diffusivity of concentration but also the valuable conductivity，as the consequences，we can know that the optimal porosity of GDL is 0.6，and the optimal porosity of catalyst layer is 0.55。In thickness，when we decrease the thickness of GDL，we can get better performance for the cell，on the other hand，the thickness of catalyst layer is thinner，so decrease it’s thickness for raising the cell performance is not obvious。

並列關鍵字

proton exchange membrane fuel cell、conductivity

參考文獻

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