直接甲醇燃料電池性能分析

Study on the Performance of a Direct Methanol Fuel Cell

吳宏道(Hung-Tao Wu)

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(2006年)

摘要

摘 要
本研究的目的在於探討操作變因對DMFC的I-V曲線與開路電位的影響，操作變因包括改變電池的溫度、甲醇濃度、陰極進料的種類（氧氣或空氣）與其流量。
實驗結果顯示，電池效能隨著溫度升高而增加；最佳的甲醇操作濃度為2M，越高濃度的甲醇於高溫操作下，甲醇滲透的情形會越嚴重，增加陰極的流量有助於電池效能的提升，但是當流量增加到一定值，流量再增加對電池性能幫助是有限的。
開路電位方面，在陰極無論使用空氣或氧氣，陰極流量的增加有助於開路電位值的提升，於電池溫度與甲醇濃度對開路電位的影響中，使用低濃度的甲醇時，電池溫度對開路電位的影響較甲醇濃度為大，當甲醇濃度增加時，則甲醇濃度對開路電位的影響較電池溫度為大，使用空氣時其影響的轉折甲醇濃度為0.75M，而使用氧氣時，甲醇操作濃度則提升到2M。

關鍵字：直接甲醇燃料電池、開路電位

關鍵字

直接甲醇燃料電池 ； 開路電位

並列摘要

Abstract
The objective of this study is to investigate the effects of various operating parameters on the performance of the I-V curves and open cell voltages of the DMFC. The operating parameters included cell temperature, methanol concentration and cathode fuel species (oxygen or air) and its flow rates.
The experimental results showed that cell performance was enhanced by increasing the operating the temperature and the operating optimal methanol concentration was 2M. At high temperature, when higher concentration of methanol was used, more methanol crossover was observed. The cell performance was increased with cathode flow rate up to a certain value, after which the cathode flow rate had no significant effect.
The effects of cell temperature, methanol concentration and cathode flow rate on the open circuit potential (OCV) were also studied. By using air or oxygen at the cathode side, increasing cathode flow rate was indeed useful for the OCV. On the effects of cell temperature and methanol concentration on the OCV, when using low methanol concentration, the cell temperature had more effect on the OCV than the methanol concentration. On the other hand, when using higher methanol concentration, the methanol concentration had more effect on the OCV than the cell temperature. The transition point of the operating methanol concentration by using air was 0.75M, while 2M for oxygen at the cathode side.

Keywords: Direct methanol fuel cell; Open circuit voltage

並列關鍵字

Direct methanol fuel cell ； Open circuit voltage

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