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Metallic Zn is believed to be an ideal anode for aqueous batteries, but its reversibility is deteriorated by noncompact and dendritic Zn deposition along with interfacial parasitic reactions. Herein, it is reported that introducing cholinium (Ch + ) cations into aqueous electrolytes enables a spatially compact, non-dendritic, and corrosion-free Zn electrode even at high areal capacity (5.0 and 10.0 mAh cm -2 ) using a pressure-free electrolytic cell. This strategy is applicable to various Zn-salt-based aqueous electrolytes (e.g., 1 M ZnSO 4 , Zn(CH 3 COO) 2 , and ZnCl 2 ). It is found that bulky Ch + cations create a "leveling effect" to homogenize Zn deposition and render an H 2 O poor electrical double layer near Zn by favorably absorbing on the Zn surface. Moreover, Ch + cations with -OH group disrupt the original H-bonded network of water to reduce H 2 O-induced side reactions and promote the Zn 2+ de-solvation by forming H-bond with H 2 O. As a result, the Zn electrode in the optimized 1 M ZnSO 4 with 4 M Ch + electrolyte manifests remarkable electrochemical performances involving high Coulombic efficiency of 99.6% in Zn//Cu cell and prolonged cycling stability over 2000 h in Zn//Zn cell (1.0 mA cm -2 , 1.0 mAh cm -2 ). This work provides a new strategy for the design of compact and dendrite-free Zn battery chemistry.

Crystallography modulation of zinc (Zn) metal anode is promising to promote Zn reversibility in aqueous electrolytes, but efficiently constructing Zn with specific crystallographic texture remains challenging. Herein, we report a current‐controlled electrodeposition strategy to texture the Zn electrodeposits in conventional aqueous electrolytes. Using the electrolytic cell with low‐cost Zn(CH3COO)2 electrolyte and Cu substrate as a model system, the texture of as‐deposited Zn gradually transforms from (101) to (002) crystal plane as increasing the current density from 20 to 80 mA cm−2. Moreover, the high current accelerates the Zn nucleation rate with abundant nuclei, enabling uniform deposition. The (002) texture permits stronger resistance to dendrite growth and interfacial side reactions than the (101) texture. The resultant (002)‐textured Zn electrode achieves deep cycling stability and supports the stable operation of full batteries with conventional V/Mn‐based oxide cathodes.

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