質子交換膜燃料電池穩態性能的數學分析

Mathematical Analysis of the Steady Performance of a Proton Exchange Membrane Fuel Cell

本文將質子交換膜燃料單電池的實測數據資料，利用回歸分析求得代表電池活化極化損失與歐姆極化損失的半經驗公式係數值，對不同的電池運轉狀態正確的計算其極化曲線。燃料電池在相同電流時，活化極化損失的半經驗公式計算電壓與實測電壓之最大誤差為0.0875伏特，而歐姆極化損失的計算電壓與實測電壓之最大誤差值0.007025伏特，此結果顯示單電池的性能，能有效的以半經驗公式求得，也能延伸使用在計算分析電池堆或燃料電池系統的發電陸能。對質子交換膜燃料電池而言，提高其運轉溫度或壓力，通常都能使其發電性能提升，但運轉在高溫的燃料電池，會因水的蒸發使質子交換膜乾燥而降低其發電性能，尤其是陰極使用空氣為燃料時，其發電效能的下降更明顯。對發電性能的提升，增加燃料電池陰極壓力會優於提高陽極壓力。 In this paper, by the regression analysis of experimental data from proton exchange membrane fuel cell measurement, the parameters of semi-empirical equation for the voltage loss from activation and ohmic overvoltage can be found. The polarization curves of fact cell operating at various steady states can also he calculated accurately. The max voltage deviations between the calculation from the semi-empirical equation and the measurement data of the activation and ohmic overvoltage are 0.0875 (V) and 0.007025 (V) respectively. Therefore, the semi-empirical equation can be used to calculate the performance of single cell and stacks. The performance of PEM fad cell can be improved by raising its operating temperature and pressure. However, membrane conductivity and fuel cell performance decrease at high temperature by a greater rate of water evaporation and the membrane dry out. Especially the performance decreases obviously for using the air to the cathode. The fuel cell performance increases by raising the pressure of cathode is higher than that raising the same pressure of anode.