The rapidly growing demand for wearable and portable electronics has driven the recent revival of flexible Zn‐ion batteries (ZIBs). However, issues of dendrite growth and low the flexibility of Zn metal anode still impede their practical application. Herein, 3D nitrogen‐doped vertical graphene nanosheets in situ grown on carbon cloth (N‐VG@CC) are proposed to enable uniform Zn nucleation, thereby obtaining a dendrite‐free and robust Zn anode. The introduced zincopilic N‐containing groups in N‐VG effectively reduce the Zn nucleation overpotential by enhancing the interaction between Zn2+ ion and carbon substrate, as confirmed by density functional theory calculations, thus achieving uniform distribution of Zn nucleus. Moreover, the 3D nanosheet arrays can homogenize electric distribution, which optimizes the subsequence Zn deposition process and realizes the highly reversible Zn plating/stripping process. Consequently, the as‐prepared Zn@N‐VG@CC anode exhibits an improved overall electrochemical performance compared with Zn@CC. As a proof‐of‐concept application, the high‐performance Zn@N‐VG@CC electrodes are successfully employed as anodes for coin and flexible quasi‐solid‐state ZIBs together with MnO2@N‐VG@CC (deposited MnO2 nanosheets on N‐VG@CC) as cathodes. More importantly, the flexible ZIB exhibits impressive cycling stability with 80% capacity retention after 300 cycles and outstanding mechanical flexibility, indicating a promising potential for portable and wearable electronics.

Achieving long-term stable zinc anodes at high currents/capacities remains a great challenge for practical rechargeable zinc-ion batteries. Herein, we report an imprinted gradient zinc electrode that integrates gradient conductivity and hydrophilicity for long-term dendrite-free zinc-ion batteries. The gradient design not only effectively prohibits side reactions between the electrolyte and the zinc anode, but also synergistically optimizes electric field distribution, zinc ion flux and local current density, which induces preferentially deposited zinc in the bottom of the microchannels and suppresses dendrite growth even under high current densities/capacities. As a result, the imprinted gradient zinc anode can be stably cycled for 200 h at a high current density/capacity of 10 mA cm−2/10 mAh cm−2, with a high cumulative capacity of 1000 mAh cm−2, which outperforms the none-gradient counterparts and bare zinc. The imprinted gradient design can be easily scaled up, and a high-performance large-area pouch cell (4*5 cm2) is also demonstrated.

Aqueous zinc‐ion batteries are highly desirable for sustainable energy storage, but the undesired Zn dendrites growth severely shortens the cycle life. Herein, a triple‐gradient electrode that simultaneously integrates gradient conductivity, zincophilicity, and porosity is facilely constructed for a dendrite‐free Zn anode. The simple mechanical rolling‐induced triple‐gradient design effectively optimizes the electric field distribution, Zn2+ ion flux, and Zn deposition paths in the Zn anode, thus synergistically achieving a bottom‐up deposition behavior for Zn metals and preventing the short circuit from top dendrite growth. As a result, the electrode with triple gradients delivers a low overpotential of 35 mV and operates steadily over 400 h at 5 mA cm‐2/2.5 mAh cm‐2 and 250 h at 10 mA cm‐2/1 mAh cm‐2, far surpassing the non‐gradient, single‐gradient and dual‐gradient counterparts. The well‐tunable materials and structures with the facile fabrication method of the triple‐gradient strategy will bring inspiration for high‐performance energy storage devices.

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