A Focused Review of Anthraquinone Derivatives for Aqueous Soft‐Gel Electrode Batteries

ABSTRACT Electrode design is crucial for achieving stable battery performance. Traditionally, electrode materials are categorized into solid‐ and liquid‐state systems with distinct physical states. Between these two regimes exists a continuum of intermediate physical states, collectively referred to as soft‐gel states, characterized by the absence of a rigid atomic framework and by restricted molecular mobility. By exploiting the strong water affinity of inorganic ions such as sulfate anions and the comparatively weak water affinity of certain water‐soluble polymers, a distinct soft‐gel phase can spontaneously form, providing a robust electrode‐electrolyte interfacial architecture. Guided by the octanol‐water partition coefficient ( K ow ), this approach enables the construction of ion‐exchange‐membrane‐free soft‐gel electrode batteries with ultralong operational lifetimes. In this review, we highlight the modification strategies of anthraquinone derivatives in redox‐flow batteries and discuss their potential integration into soft‐gel hosts, thereby illustrating the feasibility of constructing soft‐gel electrode batteries for durable aqueous energy storage.