The Effects of Channel Depths on the Performance of Proton Exchange Membrane Fuel Cells with Metallic Bipolar Plates

金屬雙極板之流道深度對質子交換膜燃料電池性能的影響

洪榮崇(Jung-Chung Hung)

《中國機械工程學刊》 33卷3期 (2012/06) Pp. 265-270

https://doi.org/10.29979/JCSME.201206.0010

摘要

雙極板中的流場是提供氣體均勻分布在MEA表面上使氣體能有效參與化學反應與排水的管道，而流道形式與幾何尺寸皆能直接影響燃料電池的性能。本研究以SUS316L不鏽鋼薄板作為金屬雙極板材料，並利用微雕模放電加工（micro electrical discharge die sinking）製作流場面積為4cm^2的三蛇蛇形流道，流道寬度與肋寬度皆為500μm，流道深度為200μm、400μm、600μm的金屬雙極板。研究中，以氣體擴散層為碳紙的MEA與三種不同流道深度金屬雙極板進行電池性能測試，並以陽極進氣流量為變數，探討流道深度與氣體流量對燃料電池性能的影響。實驗結果顯示流道深度會影響電池性能，流道深度太淺或太深均會降低電池的性能，而深度為400μm有最佳性能的表現。其原因為流道深度600μm比400μm深，流道內壓力降較低，造成氣體較無法有效反應至全流場面積，所以電流性能有些降低。當流道深度降低為200μm，會因流道深度過淺而影響質量傳輸效率，降低電池的性能。

並列摘要

The flow channels on bipolar plates distribute fuels to the surface of membrane electrode assembly (MEA). The geometry and design of flow channels have strong effects on the cell performance. This study fabricates the metallic bipolar plates using die-sinking micro electrical discharge. The SUS316L stainless steel is selected as the plate material. The flow field is a three-pass serpentine structure, of which both the rib and channel widths are 500 um and the channel depths are varied as 200, 400 and 600 μm, in a reaction area of 4cm^2. During the test, this study assemblies a cell with the carbon-paper MEA. The performance of the cell is evaluated based on three different channel depths with varying anode flow rates.The results indicate that the cell performance is slightly influenced by the channel depths. The cell with channel depth of 400μm yields best results. For the deep channel depth (600μm), the gas pressure is relatively low and the fuel is distributed less effectively to the entire reaction area. For the shallow channel depth (200μm), the efficiency of mass transport is relatively poor. Both cases lower the performance of the fuel cell.

並列關鍵字

Metallic bipolar plate ； MEA: Fuel cell ； channel depth