本研究發展出一套自動化燃料供給系統應用於為噴霧式直接甲醇燃料電池(DMFCs)。以垂直噴霧形式改善傳統式燃料供應上遭遇之困難，不僅大幅增加觸媒反應面積，亦可簡化構造達到節省成本與系統耗能(BOPs)之目的。
近年來，蛇腹型流道式廣泛運用於燃料電池進料端，但此平行燃料供給方式有幾個缺點，陽極端反應產物二氧化碳氣泡會阻塞於流道板內，造成反應面積下降，導致觸媒無法有效利用，且濃度、壓力及溫度梯度造成反應不均勻的問題。
本研究希望發展出垂直供應燃料方式解決上述之問題，利用針尖與壓電元件之間產生的毛細吸引力縮小液珠粒徑，達到微量噴霧直接推送到膜電極組(MEA)進行反應，在燃料輸送上不需使用到傳統石墨流道板，因此可以克服上述之問題，且設計無壓力梯度所造成之壓差，可降低泵浦輸送上能量之損耗。
依照微噴霧式燃料供給至膜電極阻(MEA)的型態可分為擴散型與直接供應型。將微噴霧擴散型與直接未加裝石墨流道板之液態循環方式比較，其結果可發現擴散型以10%甲醇混合液供應，其功率密度峰值可達到55mW*cm-2遠高於循環式(40 mW*cm-2)，並可在於40 mW*cm-2穩定操作30分鐘。
在燃料消耗上，微噴霧式直接供應型可將燃料供應濃度從2M提升到5M，配合Labview控制定電流模式下燃料輸送之時機，精準控制負載端能量輸出所需的燃料使用量，系統操作經過空氣中斷(Air starvation)、定電流負載(Feeding fuel)、定電壓負載(Fuel consumption)的過程，不會有甲醇供應濃度過高或供應量過多的問題，由實驗結果可得知依照此燃料供應邏輯，長時間操作於定電流(350mA)模式下有一穩定功率(12mW*cm-2)輸出，期望能增加燃料電池可應用之範圍。

In this paper, a micro-droplets fuel supply system has been developed for direct methanol fuel cells (DMFCs) by piezoelectric actuation. Compared with common serpentine flow plate, this new fuel supply mode can improve fuel usage rate and power density while lower down carried fuel volume and fuel crossover issue in DMFCs.
A micro droplets device with various concentration of fuel supply was tested and expected to find the most suitable fuel supplying mode. PZT ceramic was used to actuate droplets. A syringe needle tip was fixed 0.2-0.5mm above the piezo actuator surface to provide fuel for atomizing into 4-5μm droplets. The droplet size was much smaller than Si-based nozzle. Methanol mixture in tank transported by micro pump would be broken by piezoelectric actuation into droplets and sprayed onto the anode of DMFCs directly. Air at cathode was introduced convectively by a fan, and the cell was operated at room temperature. When the device was setup, various concentration of the fuel was supplied to the cell. The results showed that methanol mixture reaching 6M is the optimized concentration for the cell. Compared to the circulatory system, micro-droplets system, could greatly improve power density at the same condition (60 Celsius). On the other hand, the voltage fluctuated more drastically in micro-droplets system, and it enables the usage of higher concentration methanol fuel (5M) relative to circulatory flow system (2M), resulting in a higher peak power density at 32.5mW*cm-2 than that (20.5mW*cm-2) of the circulatory system at 0.4V.

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