High ionic conductivity membranes can be used to minimize ohmic losses in electrochemical devices such as fuel cells, flow batteries, and electrolyzers. Very high hydroxide conductivity was achieved through the synthesis of a norbornene-based tetrablock copolymer with an ion-exchange capacity of 3.88 meq/g. The membranes were cast with a thin polymer reinforcement layer and lightly cross-linked with N,N,N',N'-tetramethyl-1,6-hexanediamine. The norbornene polymer had a hydroxide conductivity of 212 mS/cm at 80°C. Light cross-linking helped to control the water uptake and provide mechanical stability while balancing the bound (i.e. waters of hydration) vs. free water in the films. The films showed excellent chemical stability with <1.5% conductivity loss after soaking in 1 M NaOH for 1000 h at 80°C. The aged films were analyzed by FT-IR before and after aging to confirm their chemical stability. A H2/O2 alkaline polymer electrolyte fuel cell was fabricated and was able to achieve a peak power density of 3.5 W/cm2 with a maximum current density of 9.7 A/cm2 at 0.15 V at 80°C. The exceptionally high current and power densities were achieved by balancing and optimizing water removal and transport from the hydrogen negative electrode to the oxygen positive electrode. High water transport and thinness are critical aspects of the membrane in extending the power and current density of the cells to new record values.

中文翻译：

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水传输在高电导率和高功率碱性燃料电池中的重要性

高离子电导率膜可用于将电化学装置（例如燃料电池、液流电池和电解槽）中的欧姆损失降至最低。通过合成离子交换容量为 3.88 meq/g 的降冰片烯基四嵌段共聚物，实现了非常高的氢氧化物电导率。膜浇铸有薄的聚合物增强层，并与 N,N,N',N'-四甲基-1,6-己二胺轻微交联。降冰片烯聚合物在 80°C 下的氢氧化物电导率为 212 mS/cm。轻交联有助于控制吸水率并提供机械稳定性，同时平衡薄膜中的结合水（即水合水）与游离水。在 80°C 下在 1 M NaOH 中浸泡 1000 小时后，薄膜表现出优异的化学稳定性，电导率损失 <1.5%。在老化前后通过 FT-IR 分析老化的薄膜以确认其化学稳定性。制造了一个 H2/O2 碱性聚合物电解质燃料电池，能够在 80°C 和 0.15 V 下实现 3.5 W/cm2 的峰值功率密度和 9.7 A/cm2 的最大电流密度。异常高的电流和功率密度是通过平衡和优化水从氢负极到氧正极的去除和传输来实现的。在将电池的功率和电流密度扩展到新的记录值方面，高水传输和薄度是膜的关键方面。80°C 时为 15V。异常高的电流和功率密度是通过平衡和优化水从氢负极到氧正极的去除和传输来实现的。在将电池的功率和电流密度扩展到新的记录值方面，高水传输和薄度是膜的关键方面。80°C 时为 15V。异常高的电流和功率密度是通过平衡和优化水从氢负极到氧正极的去除和传输来实现的。在将电池的功率和电流密度扩展到新的记录值方面，高水传输和薄度是膜的关键方面。