Redox flow batteries (RFBs) are promising electrochemical energy storage systems, offering vast potential for large-scale applications. Their unique configuration allows energy and power to be decoupled, making them highly scalable and flexible in design. Aqueous RFBs stand out as the most promising technologies, primarily due to their inexpensive supporting electrolytes and high safety. For aqueous RFBs, there has been a skyrocketing increase in studies focusing on the development of advanced functional materials that offer exceptional merits. They include redox-active materials with high solubility and stability, electrodes with excellent mechanical and chemical stability, and membranes with high ion selectivity and conductivity. This review summarizes the types of aqueous RFBs currently studied, providing an outline of the merits needed for functional materials from a practical perspective. We discuss design principles for redox-active candidates that can exhibit excellent performance, ranging from inorganic to organic active materials, and summarize the development of and need for electrode and membrane materials. Additionally, we analyze the mechanisms that cause battery performance decay from intrinsic features to external influences. We also describe current research priorities and development trends, concluding with a summary of future development directions for functional materials with valuable insights for practical applications.

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水系氧化还原液流电池功能材料：优点与应用

氧化还原液流电池（RFB）是一种很有前途的电化学储能系统，为大规模应用提供了巨大的潜力。它们独特的配置可以实现能量和功率的解耦，从而使其设计具有高度可扩展性和灵活性。水性 RFB 成为最有前途的技术，主要是因为其廉价的支持电解质和高安全性。对于水性 RFB，专注于开发具有卓越优点的先进功能材料的研究急剧增加。它们包括具有高溶解度和稳定性的氧化还原活性材料、具有优异机械和化学稳定性的电极以及具有高离子选择性和电导率的膜。本综述总结了目前研究的水性 RFB 类型，从实用角度概述了功能材料所需的优点。我们讨论了可以表现出优异性能的氧化还原活性候选物的设计原则，范围从无机到有机活性材料，并总结了电极和膜材料的发展和需求。此外，我们还从内在特征到外部影响分析了导致电池性能衰减的机制。我们还描述了当前的研究重点和发展趋势，最后总结了功能材料的未来发展方向，并对实际应用提出了宝贵的见解。