第四章 結果與討論
4.4 燃料電池組之效能
4.4.1 Nafion 膜電極組燃料電池之效能
Nafion 薄膜組裝之膜電極組,其極化曲線與功率密度曲線如 Figure 4-23 及 Figure 4-24 所示。結果顯示,燃料電池組之開環電壓(open circuit voltage, OCV)為 0.820 V,在電流密度(current density)為 240.0 mA/cm2時,
具有最大功率密度(power density)約為 66.2 mW/cm2。
91
(a)
(b)
Figure 4-22 Photographs of membrane electrode assemblys (MEA).
(a) Nafion-based MEA, 5cm x 5cm
(b) PSS/ionic liquid -based MEA, 1cm x 1cm
92
Figure 4-23 Polarization curve of a fuel cell using Nafion-based MEA H2 flow rate:100 mL/min(70℃)
O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:0.5 mg/cm2 Pt/C loading of Cathode:0.5 mg/cm2 Electrode area:5cm x 5cm
93
Figure 4-24 Power density of a fuel cell using Nafion-based MEA H2 flow rate:100 mL/min(70℃)
O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:0.5 mg/cm2 Pt/C loading of Cathode:0.5 mg/cm2 Electrode area:5cm x 5cm
94
95
(a)
(b)
Figure 4-25 Performance of a fuel cell using 32mol% PSS membrane-based MEA. (a) Polarization curve ; (b) Power density vs.current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
96
(a)
(b)
Figure 4-26 Performance of a fuel cell using 32mol% PSS/[HMIM][Cl]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
97
(a)
(b)
Figure 4-27 Performance of a fuel cell using 32mol% PSS/[HMIM][Br]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
98
(a)
(b)
Figure 4-28 Performance of a fuel cell using 32mol% PSS/[HMIM][I]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
99
4.4.2.2 32mol%磺酸化聚苯乙烯/[HMIM]非鹵素系列離子液體 複合膜電極組燃料電池效能
以 32mol%磺酸化聚苯乙烯與[HMIM]非鹵素系列離子液體,依不同 磺酸根/離子液體莫耳比例(1:0.10、1:0.25、1:0.50)製備質子交換複合膜,
對各種不同比例複合膜之膜電極組,進行燃料電池效能測試。
各種莫耳比例之 PSS/[HMIM][BF4]複合膜,其 MEA 效能如 Figure 4-29 所示,開環電壓介於 0.750~0.908 V 間,最大功率密度約為 8.6~8.9 mW/cm2, 相 對 應 電 流 密 度 為 28.2~32.8 mA/cm2, 相 對 應 電 壓 介 於 0.274~0.305 V。
各種莫耳比例之 PSS/[HMIM][PF6]複合膜,其 MEA 效能如 Figure 4-30 所示,開環電壓介於 0.682~0.828 V 間,最大功率密度為 3.4~10.7 mW/cm2, 相 對 應 電 流 密 度 為 13.0~43.6 mA/cm2, 相 對 應 電 壓 為 0.247~0.266 V。
各種莫耳比例之 PSS/[HMIM][SCN]複合膜,其 MEA 效能如 Figure 4-31 所示,開環電壓介於 0.749~0.824 V,最大功率密度為 4.5~5.6 mW/cm2, 相對應電流密度為16.0~22.6 mA/cm2,相對應電壓介於0.247~0.282 V。
100
(a)
(b)
Figure 4-29 Performance of a fuel cell using 32mol% PSS/[HMIM][BF4] composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
101
(a)
(b)
Figure 4-30 Performance of a fuel cell using 32mol% PSS/[HMIM][PF6] composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
102
(a)
(b)
Figure 4-31 Performance of a fuel cell using 32mol% PSS/[HMIM][SCN]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
103
104
(a)
(b)
Figure 4-32 Performance of a fuel cell using 40mol% PSS membrane-based MEA. (a) Polarization curve ; (b) Power density vs.current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
105
(a)
(b)
Figure 4-33 Performance of a fuel cell using 40mol% PSS/[HMIM][Cl]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
106
(a)
(b)
Figure 4-34 Performance of a fuel cell using 40mol% PSS/[HMIM][Br]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
107
(a)
(b)
Figure 4-35 Performance of a fuel cell using 40mol% PSS/[HMIM][I]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
108
4.4.3.2 40mol%磺酸化聚苯乙烯/[HMIM]非鹵素系列離子液體 複合膜電極組燃料電池效能
以 40mol%磺酸化聚苯乙烯與[HMIM]非鹵素系列離子液體,依不同 磺酸根/離子液體莫耳比例(1:0.10、1:0.25、1:0.50)製備質子交換複合膜,
對各種不同比例複合膜之膜電極組,進行燃料電池效能測試。
各種莫耳比例之 PSS/[HMIM][BF4]複合膜,其 MEA 效能如 Figure 4-36 所示,開環電壓介於 0.710~0.789 V 間,最大功率密度約為 7.6~9.7 mW/cm2, 相 對 應 電 流 密 度 為 21.5~32.0 mA/cm2, 相 對 應 電 壓 介 於 0.305~0.368 V。
各種莫耳比例之 PSS/[HMIM][PF6]複合膜,其 MEA 效能如 Figure 4-37 所示,開環電壓介於 0.423~0.820 V 間,最大功率密度為 2.5~14.3 mW/cm2, 相 對 應 電 流 密 度 為 12.3~35.0 mA/cm2, 相 對 應 電 壓 為 0.204~0.409 V。
各種莫耳比例之 PSS/[HMIM][SCN]複合膜,其 MEA 效能如 Figure 4-38 所示,開環電壓介於 0.746~0.831 V,最大功率密度為 5.7~10.4 mW/cm2, 相 對 應 電 流 密 度 為 15.0~28.0 mA/cm2, 相 對 應 電 壓 約 為 0.251~0.387 V。
109
(a)
(b)
Figure 4-36 Performance of a fuel cell using 40mol% PSS/[HMIM][BF4] composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
110
(a)
(b)
Figure 4-37 Performance of a fuel cell using 40mol% PSS/[HMIM][PF6] composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
111
(a)
(b)
Figure 4-38 Performance of a fuel cell using 40mol% PSS/[HMIM][SCN]
composite membranes-based MEA. (a) Polarization curve ; (b) Power density vs. current density.
H2 flow rate:100 mL/min(70℃) O2 flow rate:100 mL/min(65℃) Cell temperature:50℃
Pt/C loading of Anode:5 mg/cm2 Pt/C loading of Cathode:5 mg/cm2 Electrode area:1cm x 1cm
112 離子液體比較也相當吻合。1H-NMR 圖譜如 Figure 4-9、Figure 4-10、Figure 4-11 所示。合成的離子液體1H-NMR 圖譜,各個 chemical shift 位置上,