本研究針對DMFC在平面式電池組，提出以不同燃料供給路徑設計，對於平面配置模組化(以4顆為一個單位)設計。利用微機電 (MEMS) 製程及微電鑄技術製作出微型直接甲醇燃料電池之流道，且組裝成總反應面積 1.92 cm2 之4個分電池的平板式微型直接甲醇燃料電池組。本實驗以單顆電池在不同的流道寬度、流量、溫度及濃度下找出實驗最佳參數後，以不同燃料供給路徑配合不同電池數量(2、4顆)的電池組來進行 VI/PI 的性能測試，並以長時間 (50 hrs) 觀察不同路徑下電池組的性能變化及電池組中各分電池的性能影響。實驗結果顯示單電池最佳參數為：流道寬度600 μm、濃度0.5 M、溫度80℃以及流量5 sccm，2顆電池組的串聯供給路徑性能表現優於並聯，4顆電池組在type4有最佳的電池性能表現最大功率密度為63.6 mW/cm2 、最大電流513.5 mA/cm2，相較於type1的並聯形式提升約21.6%。

This study aimed at DMFC in the planar battery pack, proposed with varied fuel supply path design, modular configuration for the plane (in units of 4) design. Using MEMS process and micro-electroforming technology to produce a miniature direct methanol fuel cell flow field plate and assembled into a total reaction area of 1.92 cm2 of 4 cell plate micro direct methanol fuel cell stack. This experiment with a single cell in varied flow channel width, flow rate, temperature and concentration to find the best experimental parameters, the VI/PI curve was tested with varied fuel supply paths with different battery numbers (2, 4), and in a long time (50 hrs) observed under varied paths of battery performance changes and battery pack sub-battery performance impact. Experimental results show that the best cell parameters are: flow path width 600 μm, concentration 0.5 M, temperature 80℃ and flow rate 5 sccm, 2-cell stack in series supply path performance is better than parallel. The 4-cell stacks have the best performance in type 4 with a peak power density of 63.6 mW/cm2 and a limiting current density of 513.5 mA/cm2, an increase of approximately 21.6% over the parallel version of type 1.

致謝 ii
中文摘要 iii
ABSTRACT iv
CONTENTS v
LIST OF FIGURES vii
LIST OF TABLES ix
NOMENCLATURE x
CHAPTER 1 INTRODUCTION 1
1.1 Background 1
1.2 Types of fuel cell 2
1.3 Literature survey 7
1.4 Objective 16
CHAPTER 2 PRINCIPLE AND COMPONENTS 20
2.1 Principle of DMFC 20
2.2 Main component 23
CHAPTER 3 THEORETICAL BACKGROUND 33
3.1 Electrode Thermodynamics 33
3.2 Polarization 41
3.3 Methanol Crossover 45
CHAPTER 4 EXPERIMENTS 49
4.1 Experimental apparatus 49
4.2 Material property 53
4.3 Experimental procedure 56
CHAPTER 5 DATA REDUCTION AND UNCERTAINTIES 63
CHAPTER 6 RESULTS AND DISCUSSION 68
6.1 Effect of operating conditions on the performance of single cell 68
6.2 Effect of fuel supply path on the performance of cell stack 73
6.3 Each individual cell on the performance comparison of cell stack 74
6.4 Long-term experiment of 4-cell stack 77
CHAPTER 7 CONCLUSION AND RECOMMENDATIONS 95
7.1 Conclusion 95
7.2 Recommendations for future work 96
REFERENCES 97
Appendix A 102

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