用于在氧化还原流电池中使用的聚胺膜的设计
J C Duburg1,2, B Chen2, S Holdcroft2
1Electrochemistry Laboratory, Paul Scherrer Institut CH-5232 Villigen PSI Switzerland lorenz.gubler@psi.ch.
概括
聚胺膜为氧化还原流电池 (VRFB) 提供了更好的导电性. 65%甲基化膜平衡了效率和容量保留,性能优于NafionTM.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 聚合物化学 聚合物化学
背景情况:
- 聚二胺 (PBI) 膜正在探索作为替代NafionTM用于氧化还原流电池 (VRFB) 的替代品.
- PBI 膜具有良好的容量保留,但其离子导电性较低.
- 将PBI化为聚二增强了离子导电性,此前在燃料电池和水电解中使用过.
研究的目的:
- 在VRFB中研究甲基-p-甲基聚胺 (HMT-PMBI) 膜的性能.
- 为了将膜特性,特别是甲基化程度与VRFB性能相关联.
- 评估HMT-PMBI作为VRFB应用中NafionTM的潜在替代品.
主要方法:
- 合成和表征不同程度甲基化 (56-89%) 的HMT-PMBI膜.
- 测量膜离子导电性和酸性介质中自由水的分数.
- 测试单细胞VRFB性能,包括在200个周期内保持效率和容量.
主要成果:
- 将甲基化程度从56%提高到89%增加了离子导电性和自由水的分数.
- 较高的甲基化度提高了细胞性能,但降低了容量保留.
- 具有65%甲基化的HMT-PMBI膜显示出平衡的性能,实现了5%更高的效率和NafionTM NR212的两倍容量保留.
结论:
- 对于VRFB应用,HMT-PMBI膜显示出有前途,比传统的PBI提供了更好的离子导电性.
- 甲基化程度是影响膜性能的关键因素,影响了离子导电性和稳定性.
- 65%的甲基化水平为VRFB运行提供了最佳平衡,在关键指标上表现优于NafionTM.
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