本計畫延續上一年度之研究工作，分別利用實驗與數值模擬方法，深入探討三大主題：(1)電池堆優化設計、(2) SOFC多孔介質流道流場模擬分析和(3)不同流道設計單電池之電池性能實作測試和分析，分別敘述如下。(1)電池堆優化設計：將改良已有之實驗水力平台，並擴展其操作條件，進而測試不同的多層電池堆設計，並使流道雷諾數可操作於Re = 1 ~ 500的範圍。此外，將建立三維電池電化學數值模式，研究電池堆流場均勻度對電池性能之影響。(2) SOFC多孔介質流道流場模擬與分析：擬建立不同類型的多孔介質流場模擬設備，並使用折射率契合技術與質點影像測速儀，來進行多孔介質內之速度場量測。我們除了研究孔隙率與雷諾數因素對多孔介質內部動量傳輸之影響，並將利用由質點影像測速技術所獲得的實驗數據，來提供SOFC三維電化學數值模式中計算多孔介質表面和內部傳輸現象所需之邊界條件。(3)單電池性能測試：將首次以實際電化學實驗方法，研究流場均勻度對電池性能的影響。我們將針對不同流場設計之單電池，進行一系列的性能測試，量測電流-電壓曲線、電化學阻抗頻譜以及燃料使用率等重要的電池性能參數，並將使用掃描式電子顯微鏡以及X光粉末繞射儀，來分析SOFC電極微結構之變化，進而建立診測電池劣化機制之分析知識。本計畫將全力配合核研所正開發中之SOFC研究，著重於建立基礎學理電池性能劣化分析與電池元件優化設計等知識，期能對我國正推動之新能源技術，即SOFC發電系統計畫，所需之學理機制，有所貢獻。 This is a second-year proposal focusing on three topics: (1) Optimal design of cell-stack for uniform flow distribution, (2) modeling and analysis of flow distributions in porous electrodes of SOFC, and (3) single cell performance test and analysis using different flow designs. For the first topic, an already established hydraulic platform will be continuously modified to extend its operating conditions, so that, velocity distributions in different modules of multi-cell stacks over a wide range of flow-channel Reynolds number (Re) from 1 to 500 can be achieved. Furthermore, a three-dimensional, cell electrochemical model will be developed to investigate effects of flow uniformity in the cell-stack to the cell performance. Concerning the second topic, different types of porous flows will be established and the velocity distributions in these porous flows are measured using the particle image velocimetry together with the refractive index matching technique. Not only the effects of porosity and Re on the momentum transport in porous electrodes of SOFC will be evaluated, but also the correct boundary conditions at the porous interface to be used in 3D numerical model for SOFC will be obtained from experimental velocity data. For the third topic, the effect of flow uniformity on cell performance will be investigated experimentally using a single cell in a real testing platform for the first time. A series of single-cell testing experiments with different flow distributors will be carried out to obtain the important information of cell performance, such as the current-voltage curves, the electrochemical impedance spectroscopy, and the fuel utilization rate. Moreover, both the scanning electron microscope (SEM) and the X-ray diffraction (XRD) will be used to detect the failure of the electrodes. The obtained data are essential for diagnosing the degradation mechanisms for SOFC. This proposal aims to provide fundamental knowledge of the optimal cell design and mechanism of the cell degradation that are of help to the SOFC program currently developed by the Institute of Nuclear Energy Research (INER) 研究期間 : 9801 ~ 9812
