Salt cavern with a volume of hundreds of thousands of cubic meters for storing electrolyte has been considered as a promising large-scale storage technology. However, the solubility and electrochemical stability of active organic species are significantly limited in saturated brine solution. Here, an unsymmetrical two-electron viologens with high solubility in aqueous system is synthesized via a simple two-step reaction route. As a novel two-electron storage anolyte, its electrochemical properties are investigated in detail by cyclic voltammetry and rotating disk electrode voltammetry. Paired with (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) derivatives, the battery delivers an exceptionally high cell voltage of 1.63 V, an energy efficiency of ~80%, and an average 99.95% capacity retention per cycle at 30 mA/cm². To extend in saturated brine solution, the battery also exhibits a high cell efficiency and stable cycle performance, providing a promising strategy for developing the large scale salt-cavern redox flow batteries.

具有数十万立方米的用于存储电解质的盐穴已经被认为是一种有前途的大规模存储技术。但是，在饱和盐水溶液中，活性有机物的溶解度和电化学稳定性受到很大限制。在此，通过简单的两步反应路线合成了在水性体系中具有高溶解度的不对称两电子紫精。作为一种新型的两电子存储阳极电解液，通过循环伏安法和转盘电极伏安法详细研究了其电化学性质。与（2,2,6,6-四甲基哌啶-1-基）氧基（TEMPO）配对使用，该电池可提供1.63 V的极高电池电压，约80％的能量效率和99.95％的平均容量保持率每个周期30 mA / cm ²。为了在饱和盐水溶液中扩展，该电池还具有较高的电池效率和稳定的循环性能，为开发大型盐穴氧化还原液流电池提供了有希望的策略。