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Eutectic electrolytes show potential beyond conventional low‐concentration electrolytes (LCEs) in zinc (Zn)‐ion capacitors (ZICs) yet suffer from high viscosity and sluggish kinetics. Herein, we originally propose a universal theory of intrinsically decoupling to address these issues, producing a novel electrolyte termed "quasi‐eutectic" electrolyte (quasi‐EE). Joint experimental and theoretical analyses confirm its unique solution coordination structure doped with near‐LCE domains. This enables the quasi‐EE well inherit the advanced properties at deep‐eutectic states while provide facilitated kinetics as well as lower energy barriers via a vehicle/hopping‐hybridized charge transfer mechanism. Consequently, a homogeneous electroplating pattern with much enhanced Sand's time is achieved on the Zn surface, followed by a twofold prolonged service‐life with drastically reduced concentration polarization. More encouragingly, the quasi‐EE also delivers increased capacitance output in ZICs, which is elevated by 12.4 %–144.6 % compared to that before decoupling. Furthermore, the pouch cell with a cathodic mass loading of 36.6 mg cm−2 maintains competitive cycling performances over 600 cycles, far exceeding other Zn‐based counterparts. This work offers fresh insights into eutectic decoupling and beyond. [ABSTRACT FROM AUTHOR]

Regulating the electric double layer (EDL) structure of the zinc metal anode by using electrolyte additives is an efficient way to suppress interface side reactions and facilitate uniform zinc deposition. Nevertheless, there are no reports investigating the proactive design of EDL‐regulating additives before the start of experiments. Herein, a functional group assembly strategy is proposed to design electrolyte additives for modulating the EDL, thereby realizing a long‐lasting zinc metal anode. Specifically, by screening ten common functional groups, N, N‐dimethyl‐1H‐imidazole‐1‐sulfonamide (IS) is designed by assembling an imidazole group, characterized by its high adsorption capability on the zinc anode, and a sulfone group, which exhibits strong binding with Zn2+ ions. Benefiting from the adsorption functionalization of the imidazole group, the IS molecules occupy the position of H2O in the inner Helmholtz layer of the EDL, forming a molecular protective layer to inhibit H2O‐induced side reactions. Meanwhile, the sulfone group in IS, acting as a binding site to Zn2+, promotes the de‐solvation of Zn2+ ions, facilitating compact zinc deposition. Consequently, the utilization of IS significantly extending the cycling stability of Zn||Zn and Zn||NaV3O8 ⋅ 1.5H2O full cell. This study offers an innovative approach to the design of EDL regulators for high‐performance zinc metal batteries. [ABSTRACT FROM AUTHOR]

Unstable Zn interface with serious detrimental parasitic side‐reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc‐ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn‐ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn‐ions and guide the Zn‐ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc‐ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc‐ion distribution by using its positively charged −NR4+ groups. While the negatively charged −SO3− groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn‐ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side‐reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm−2, 0.25 mAh cm−2). Additionally, based on this strategy, the NH4V4O10||Zn pouch‐cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch‐cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles. [ABSTRACT FROM AUTHOR]