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Aqueous zinc‐ion batteries (AZIBs) are emerging as one of the most reliable energy storage technologies for scale‐up applications, but still suffer from the instability of Zn anode, which is mainly caused by the undesirable dendrite growth and side reactions. To tackle these issues, we formulate a new aqueous electrolyte with weak solvation effect by introducing low‐dielectric‐constant acetone to achieve H2O‐poor solvation structure of Zn2+. Experimental and theoretical calculation studies concurrently reveal that such solvation structure can: i) relieve the solvated H2O related side reactions, ii) suppress the dendrite growth by boosting the desolvation kinetics of Zn2+ and iii) in situ form solid electrolyte interface (SEI) to synergistically inhibit the side reaction and dendrite growth. The synergy of these three factors prolongs the cycling life of Cu/Zn asymmetric cell from 30 h to more than 800 h at 1 mA cm−2/1 mAh cm−2, and can work at more harsh condition of 5 mA cm−2/5 mAh cm−2. More encouragingly, Zn/V2O5 ⋅ nH2O full cell also shows enhanced cycling stability of 95.9 % capacity retention after 1000 cycles, much better than that with baseline electrolyte (failing at ≈700th cycle). [ABSTRACT FROM AUTHOR]

The hydrogen evolution and dendrite issues are the notorious culprits of the limited lifespan and Coulombic efficiency (CE) of Zn anodes, particularly at harsh test conditions. Herein, considering the Lewis acidic feature of Zn2+, abundant unshared pair electrons of zincophilic Lewis bases are proposed as decent electrolyte additives to stabilize Zn anodes at "Three High" conditions (high depth of discharge, high areal capacity and high current). The unshared pair electrons can remove H2O from Zn2+ solvated sheaths and confine the activity of H2O by breaking its hydrogen bonding network. The combination of these factors effectively restricts H2O‐involved side reactions and enables dendrite‐free Zn deposition, even at harsh conditions. The effectiveness of this strategy is fully proved by a series of Lewis base molecules. Noticeably, the Zn||Zn cell with an area of 20 cm2, using DMF‐containing electrolyte can be stably cycled over 1000 h at 60 % DOD, with a 100 % CE. [ABSTRACT FROM AUTHOR]