Aqueous zinc-ion battery energy storage performance reinforced by small-molecule organic electrolyte additives through multifunctional synergistic regulation mechanisms

The practical deployment of aqueous zinc-ion batteries (AZIBs) for grid-scale energy storage remains severely constrained by the progressive degradation of zinc metal anodes—a multifaceted challenge arising from the intertwined failure modes of dendritic deposition, hydrogen evolution, surface corrosion, and irreversible passivation. This work presents a comprehensive deconstruction of the coupled degradation network that governs anode instability, establishing the self-amplifying positive feedback loop among these parasitic processes as the fundamental origin of capacity decay and safety deterioration. The regulatory functions of small-molecule organic electrolyte additives are systematically categorized into eight mechanistic pathways, including nucleation induction, electrostatic shielding, solid electrolyte interphase construction, solvation sheath reconstruction, crystallographic orientation modulation, electric double-layer restructuring, hydrogen bond network reconfiguration, and interfacial pH regulation. The synergistic interplay among these mechanisms is critically examined, revealing that solvation structure modification serves as the central hub that orchestrates cascading effects on interfacial electric field distribution, water reactivity suppression, and deposition morphology control. The analysis further identifies the transition from single-mechanism descriptions to multi-mechanism cooperative frameworks as an essential step toward predictive additive design. The persistent gap between laboratory-scale demonstrations under idealized conditions and the performance requirements for practical energy storage applications is highlighted, with particular emphasis on the need for standardized evaluation protocols, operando characterization techniques, and machine-learning-assisted molecular screening. This work establishes a systematic foundation for understanding the mechanistic complexity of organic additives and provides strategic guidance for developing high-performance aqueous zinc-ion batteries capable of meeting the durability and safety demands of stationary energy storage systems.