高溫PBI質子交換膜燃料電池陰極觸媒層多層結構之電腦數值模擬建立分析

NUMERICAL STUDY OF THE CATHODE CATALYST LAYER OF HIGH TEMPERATURE PROTON EXCHANGE MEMBRANE FUEL CELLS

蔡椀琇(Wan-Hsiu Tsai)

指導教授 ： 蘇艾

元智大學/工程學院/機械工程學系/碩士(2011年)

摘要

本文主要是利用COMSOL Multiphysics軟體來模擬高溫PBI質子交換膜燃料電池，模型操作在二維、穩態、電池操作溫度為等溫。模型包含PBI膜、觸媒層、氣體擴散層，假設觸媒層中觸媒顆粒為agglomerate model，外層被含磷酸的PBI高分子所包覆，將陰極觸媒層結構中的PBI多層化，靠近膜材端增加PBI含量，以利傳導質子；靠近氣體擴散層端減少PBI含量，以利氣體擴散。主要在分析電池內部的傳輸、極化現象和觸媒利用率。分析電池模型中設定的重要參數對電池性能的影響，如觸媒顆粒半徑、含磷酸PBI薄膜厚度、觸媒層厚度等等。模擬與實驗結果做比對，也在最後找出比實驗對照組更佳的電池性能組合。

關鍵字

PBI ； agglomerate model ； 觸媒層

並列摘要

In this study, a steady-state, isothermal and two-dimensional mathematical model of high temperature proton exchange membrane fuel cells has been developed and we using the COMSOL Multiphysics software. In this model including PBI membrane, catalyst layers, gas diffusion layer. The model treats the catalyst layer as agglomerates of polymer electrolyte coated catalyst particles. In order to find out the optimal distributions of PBI wt% across the entire thickness of cathode catalyst layers to polymer electrode membrane, it has to investigate the sensitivity parameters affecting in catalyst layers. The model presents for all transport and polarization phenomena, and compare with the experimental data for the same operating conditions. Finally, find out the optimal PBI content of cathode catalyst layers.

並列關鍵字

Polybenzimidazole (PBI) ； agglomerate model ； catalyst layer

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