对非水性回氧流电池的离子交换膜评估协议
Jessica L Tami1, Md Motiur R Mazumder2, Grace E Cook1
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, United States.
ACS applied materials & interfaces
|September 30, 2024
概括
非水性氧化还原流电池面临着膜交叉的挑战,降低了效率. 这项研究发现,所有测试的离子交换膜 (AEM) 在有机溶剂中表现不佳,突出了更好的膜开发和标准化测试协议的需要.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 储能 储能 储能 储能 储能 储能
背景情况:
- 非水性氧化还原流电池 (NRFB) 受到氧化还原活性物种通过膜交叉的限制,这会影响电池寿命和库伦比效率.
- 目前的研究重点是修改氧化还原活性分子或合成新膜以减少交叉.
- 缺乏标准化的协议,阻碍了NRFB应用中不同膜的有效比较.
研究的目的:
- 评估26种商用离子交换膜 (AEM) 在非水性溶剂中的性能.
- 用中性和阴离子氧化还原活性分子评估AEM兼容性,膨胀,离子导电性和交叉电阻.
- 提出一种标准化的评估方法,用于比较NRFB系统中的AEM.
主要方法:
- 对26种商用离子交换膜 (AEM) 的系统评估.
- 测试AEM与普通非水性电池溶剂的兼容性.
- 使用中性和阴离子分子测量氧化还原活性物种交叉.
主要成果:
- 所有评估的AEM在有机溶剂中表现不佳.
- 观察到的问题包括不受控制的胀,低离子导电性和高交叉率.
- 没有商业AEM满足了在测试的非水性系统中有效使用的要求.
结论:
- 目前的商用AEM不适合用于非水性氧化还原流电池应用,因为其显著的性能限制.
- 开发的评估方法和生成的数据为比较AEM性能提供了基础.
- 建议在未来对AEM开发和选择的研究中实施这一标准化协议.
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