質子交換膜燃料電池陰極微孔層之研究

Study on the micro-layer on the cathode of Proton Exchange Membrane Fuel Cell

蔡龍慶(Lung-Ching Tsai)

指導教授 ： 尹庚鳴

元智大學/工程學院/化學工程與材料科學學系/碩士(2007年)

https://doi.org/10.6838/YZU.2007.00111

摘要

摘要

探討氣體擴散層製作及氟化乙丙烯Fluorinated ethylene propylene (FEP)含量會對質子交換膜燃料電池內部氣體質傳、歐姆阻抗與水管理能力有所影響，因而對於燃料電池性能也有所影響，如何平衡好的氣體擴散與高的氫離子傳導，並且在高電流密度時，減少陰極水氾濫，是個相當重要的課題，因此，適當的水管理，將決定電池性能的好壞。本論文研究的重點在於探討氣體擴散層製程，以及 FEP含量與碳粉負載量對質子交換膜燃料電池性能之影響。在傳統的氣體擴散層中加入多孔性之微孔層(Micro-layer)，能有效的改善水管理能力，不僅使電池性能大幅提昇，並且能延長極限電流密度的發生。在FEP含量方面，太多或太少的 FEP含量都會對燃料電池性能有所影響，過多的FEP含量會造成擴散層中的孔隙減少，而阻礙氣體的擴散，但FEP 含量太少又無法有效的將電池內的水排出。
本研究發現60℃電池溫度時，微孔層FEP含量為20%(C:FEP=1:0.25)以及碳粉負載量為1.5mg/cm2時，會有最佳的燃料電池性能。

關鍵字：質子交換膜燃料電池，微孔層

關鍵字

質子交換膜燃料電池，微孔層

並列摘要

Abstract

The manufacturing processes and Fluorinated ethylene propylene (FEP) contents of gas diffuser layer (GDL) affect significantly the gas mass transport, ohmic loss and water management within the PEM fuel cells, which in turn, influence the performance of fuel cell. The water management within the fuel cell is considered to be an important issue for a better cell performance.
The main focus in this thesis is to study the manufacturing process, the content of the FEP, and carbon loading on the cell performance. These results are useful for choosing the optimal fabricating procedure of the GDL and the proper operating conditions of the PEMFC. The traditional GDL covered with a micro-layer can enhance the capability of water management. When the FEP contents in the GDL are too high, the gas diffusion will be difficult due to a small pore size. On the other hand, when the FEP contents are too low, the water generated in the cathode catalyst layer cannot be removed effectively.
The micro-layer with 20% FEP(C:FEP=1:0.25) at carbon loading of 1.5 mg/cm2 shows the best performance in the present study.

Keyword：PEMFC, micro-porous layer.

並列關鍵字

PEMFC, micro-porous layer

參考文獻

J. M. Leger., and C. Lamy, Ber. Bunsenges. Phys. Chem. 94, 1021(1990).

J. Larminie and A. Dicks, ”Fuel Cell Systems Explaind”, John Wiley & Sons, Inc., (2000).

T.J.Zawodzinski, J. Electrochem. Soc., 140, 1042(1993).

I. D. Raistrick, U.S.Patent , NO. 4,876,115(1989).

E. J. Taylor, J. Electrochem. Soc., 139, L45(1992).