Redox mediators (RMs), serving as intermediate electron carriers or reservoirs, play vital roles in developing new charge transfer energy storage systems with high voltage or capacity in aqueous batteries. However, the underlying mechanism and selection criteria of RMs remain unclear in aqueous batteries, which hinders the further exploitation of new RMs and aqueous battery chemistries. Herein, rather than simply compiling recent progress, we critically appraise the potential correlation between the electrochemical charge storage mechanisms and the selection criteria of RMs. For practical applications, current challenges and promising strategies are synergistically proposed, corresponding to representative applications in holistic deposition–dissolution aqueous batteries, sulfur-based aqueous batteries, and redox flow aqueous batteries. Last, this perspective provides synergistic concerns on and a roadmap for RM chemistry to render the future development of RM-assisted high-efficiency and high-energy aqueous batteries.

氧化还原介质 (RM) 作为中间电子载体或储存器，在开发具有高电压或高容量水性电池的新型电荷转移储能系统方面发挥着至关重要的作用。然而，水系电池中 RM 的潜在机制和选择标准仍不清楚，这阻碍了新 RM 和水系电池化学的进一步开发。在这里，我们不是简单地汇总最近的进展，而是批判性地评估电化学电荷存储机制与 RM 选择标准之间的潜在相关性。对于实际应用，协同提出了当前的挑战和有前景的策略，对应于整体沉积-溶解水系电池、硫基水系电池和氧化还原液流水系电池中的代表性应用。最后的，