Energy storage systems are considered one of the key components for the large-scale utilization of renewable energy, which usually has an intermittent nature for production. In this case, vanadium redox flow batteries (VRFBs) have emerged as one of the most promising electrochemical energy storage systems for large-scale application, attracting significant attention in recent years. To achieve a high efficiency in VRFBs, the polymer electrolyte membrane between the positive and negative electrodes is expected to effectively transfer protons for internal circuits, and also prevent cross-over of the catholyte and anolyte. However, the high cost of membrane materials is currently a crucial factor restricting the large-scale application of VRFBs. In this review, key aspects related to the polymer electrolyte membranes in VRFBs are summarized, including their functional requirements, characterization methods, transport mechanisms, and classification. According to its classification, the latest research progress on the polymer electrolyte membrane in VRFBs is discussed in each section. Finally, the research directions and development of next-generation membrane materials for VRFBs are proposed, aiming to present a future perspective of this component in full batteries and inspire the ongoing efforts for building high-efficiency VRFBs in the power grid.

中文翻译：

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全钒氧化还原液流电池优化膜的研究进展


储能系统被认为是大规模利用可再生能源的关键组成部分之一，可再生能源的生产通常具有间歇性。在这种情况下，全钒氧化还原液流电池（VRFB）已成为最有前景大规模应用的电化学储能系统之一，近年来引起了人们的广泛关注。为了实现 VRFB 的高效率，正极和负极之间的聚合物电解质膜有望有效地为内部电路传输质子，并防止阴极电解液和阳极电解液的交叉。然而，膜材料成本高是目前制约VRFB大规模应用的关键因素。在这篇综述中，总结了与 VRFB 中聚合物电解质膜相关的关键方面，包括其功能要求、表征方法、传输机制和分类。根据其分类，各部分讨论了VRFB中聚合物电解质膜的最新研究进展。最后，提出了下一代VRFB膜材料的研究方向和发展，旨在展示该组件在全电池中的未来前景，并激励为电网建设高效VRFB而不断努力。