本研究提出微型直接甲醇燃料電池之新式多段式流道，製作方式採用微機電以及精密加工製程。在流道設計上，包含了平行流道區、緩衝區以及水回收區。經由初步測試發現，對於此流道設計，親水性表面可提供較佳的水回收能力。在直接甲醇燃料電池陰極端的即時觀察上，發現了液態水在碳布與不鏽鋼網具有不同之行為；此外，陰極端的即時性觀察更進一步發現液態水在平行流道區的傳輸行為。結果顯示，即使在低空氣流量下(<10 ml/min)，所有可視化流道皆無阻塞之現象。本研究實驗證明了新式多段式流道確能移除直接甲醇燃料電池中陰極端產生之凝結水，避免凝結水阻塞流道。在直接甲醇燃料單電池的效能測試上，鍍金且流道結構較深之流道板，可較SiO2表面之流道板獲得約4.6倍的最大電流輸出與5.6倍最大功率輸出。

A novel design of multi-sectional flow field for cathode side of small or micro DMFC is fabricated using MEMS and precision machining processes. The flow field includes a parallel-channel section, buffer zone and recycling channels. The preliminary tests of water wetting process in the flow field show that the flow field with hydrophilic surface can provide a favorable recycling ability. The in-situ observation of actual single DMFC shows the different behaviors of water respectively associated with stainless steel mesh and carbon cloth. Furthermore, the in-situ observation indicates the water transport behavior in the parallel channels. All the channels with observation opening are found to be free from water clogging even at a low air flow rate (< 10 ml/min). This novel flow filed is experimentally demonstrated to handle the water generation and prevent water clogging in the channels. In the test of single DMFC, flow field with gold-plated surface and deeper channel depth can obtain maximum current and power output for about 4.6 and 5.6 times compared with flow field with SiO2-induced surface.

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