臺灣博碩士論文加值系統

質子交換膜燃料電池內部的電阻會影響電池組的性能，電阻包含元件自身的片電阻以及元件接觸面上之接觸電阻，而後者的影響遠大於前者。接觸電阻的大小主要由夾持壓力決定，本文首先探討夾持壓力和接觸電阻之間的關係，並使用函數式表示；而後利用有限元素分析軟體進行接觸電阻值的預測，並探討壓力分佈情形對接觸電阻的影響；結果顯示夾持壓力大小才是影響接觸電阻值的主因，當夾持壓力增加時，可以明顯降低接觸電阻，而壓力分佈均勻雖然可以降低接觸電阻，但是改善的效果非常有限。
　　壓力分佈均勻除了稍微改善接觸電阻外，對於電池組內之熱管理、水管理以及燃料傳輸亦有正面效益，本文後半段以壓力分佈之均勻性為目標，進行燃料電池組夾持端板的改良設計，並以壓力分佈的標準差來判斷壓力分佈是否均勻，然後和傳統端板比較；結果顯示本文設計之新型端板，在提供均勻壓力之性能上，遠高於傳統端板，而且經過簡單的輕量化後，重量還能低於傳統端板。

The electrical resistance in PEMFC will reduce the performance of the fuel cell stack. The electrical resistance includes the bulk resistance of the components and the contact resistance between the components, the latter has larger influence on the performance of the fuel cell than the former.
　　The contact resistance is mainly determined by the clamping pressure. In this paper, we first investigate the relation between the clamping pressure and the contact resistance, then we use some kind of functions to represent the relation. According to the relation, we can predict the contact resistance with FEM software, and investigate the effects of the contact pressure distribution on the contact resistance. We find that the contact resistance is affected by clamping pressure significantly, but lightly affected by the pressure distribution, though the uniform distribution could decrease the contact resistance.
　　In addition, the uniform distribution can improve the managements of heat, water and the transportation of the fuel. So we design the clamp endplate of the stack to provide the uniform pressure distribution. We use the standard deviation of the pressure to judge the uniformity of the pressure distribution using newly designed endplate and compare with the traditional one. The results show that the new endplate give more uniform pressure distribution than traditional endplate, and could be lighter after simple weight reduction.

致謝 i
中文摘要 ii
Abstract iii
目錄 iv
圖目錄 vii
表目錄 x
第 一 章 緒論 1
1.1 前言 1
1.2 燃料電池簡介 2
1.2.1 燃料電池發電原理 2
1.2.2 燃料電池種類 3
1.2.3 重要元件介紹 5
1.2.4 燃料電池之極化反應 6
1.3 研究動機與目的 8
1.4 研究方法 10
1.5 有限元素分析軟體介紹 12
1.6 論文架構 12
第 二 章 理論背景與文獻回顧 13
2.1 接觸電阻相關文獻整理 13
2.1.1 接觸電阻之數學模型 13
2.1.2 接觸電阻之量測 16
2.1.3 使用有限元素軟體預測燃料電池之接觸電阻 17
2.1.4 受夾持壓力影響的其他參數 19
2.1.5 其他相關的研究 20
2.2 端板形式介紹 21
2.3 螺栓扭力－夾持力轉換公式 24
2.4 文獻回顧結論 24
第 三 章 接觸電阻之實驗與預測 26
3.1 實驗目的 26
3.2 實驗說明 26
3.2.1 實驗儀器 26
3.2.2 元件材料 28
3.2.3 實驗設置 30
3.2.4 夾具設計 31
3.2.5 實驗流程 33
3.3 實驗結果 34
3.3.1 接觸電阻率計算 35
3.4 有限元素模型 37
3.4.1 模型元件 37
3.4.2 材料常數 38
3.4.3 模型簡化 39
3.4.4 邊界條件及網格化 40
3.4.5 分析結果 41
3.4.6 接觸電阻之預測 42
3.5 電池組製作及實驗驗證 43
3.5.1 元件製作 43
3.5.2 實驗器材 43
3.5.3 實驗流程 44
3.5.4 實驗結果 45
3.6 結論 46
第 四 章 接觸電阻和壓力分佈均勻性之關係 47
4.1 壓力分佈均勻性之判準 47
4.1.1 理想狀況之標準差 47
4.2 接觸電阻和SR值之關係 50
4.3 結論 52
第 五 章 端板改良設計 53
5.1 端板的改良設計 53
5.1.1 改良概念說明 53
5.1.2 端板改良雛形 54
5.1.3 輔助元件部位說明 56
5.2 性能分析 57
5.2.1 修改L值 57
5.2.2 修改W值 61
5.2.3 端板減重 62
5.3 設計結果 66
第 六 章 總結與未來方向 67
參考文獻 69

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