Aqueous rechargeable Zn metal batteries have attracted widespread attention due to the intrinsic high volumetric capacity, low cost, and high safety. However, the low Coulombic efficiency and limited lifespan of Zn metal anodes resulting from uncontrollable growth of Zn dendrites impede their practical application. In this work, a 3D interconnected ZnF2 matrix is designed on the surface of Zn foil (Zn@ZnF2) through a simple and fast anodic growth method, serving as a multifunctional protective layer. The as‐fabricated Zn@ZnF2 electrode can not only redistribute the Zn2+ ion flux, but also reduce the desolvation active energy significantly, leading to stable and facile Zn deposition kinetics. The results reveal that the Zn@ZnF2 electrode can effectively inhibit dendrites growth, restrain the hydrogen evolution reactions, and endow excellent plating/stripping reversibility. Accordingly, the Zn@ZnF2 electrode exhibits a long cycle life of over 800 h at 1 mA cm−2 with a capacity of 1.0 mAh cm−2 in a symmetrical cell test, the feasibility of which is also convincing in Zn@ZnF2//MnO2 and Zn@ZnF2//V2O5 full batteries. Importantly, a hybrid zinc‐ion capacitor of the Zn@ZnF2//AC can work at an ultrahigh current density of ≈60 mA cm−2 for up to 5000 cycles with a high capacity retention of 92.8%.

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Conventional zinc-ion batteries (ZIBs) are severely hindered by the inherent drawbacks of Zn metal anodes including dendrite growth, side reactions, and interface passivation. Developing intercalation-type anodes to fabricate rocking-chair ZIBs is a promising approach to overcome the above issues. However, the low capacity resulting from the limited transfer electron number of intercalation reactions impedes their practical applications. Herein, we report an effective strategy to break the capacity limit of layered CuS materials as a Zn-metal-free anode through activating its intrinsic conversion reaction. It is found that the preintercalation of cetyltrimethylammonium bromide in CuS (CuS@ CTMAB) significantly lowers the energy barrier of the conversion reaction, thus realizing a record-breaking capacity (367.4 mAh g −1 at 0.1 A g −1 ) as a Zn-metal-free anode based on the reversible conversion of Cu 2+ /Cu 0 . Theoretical calculation, ex situ microscopy, and spectroscopy results verify that the characteristic stepwise intercalation−conversion reaction route occurred in CuS@CTMAB. Moreover, the moderate structure transformation and good electronic conduction during the phase evolution process led to excellent cycling stability and high rate performance. Consequently, the rocking-chair ZIB full battery system utilizing CuS@CTMAB and Zn 2+preintercalated MnO 2 as the anode and cathode, respectively, exhibits exceptional capacity retention of 93.9% up to 8000 cycles at 2 A g −1 . Besides, the CuS@CTMAB anode is also compatible with high-voltage Prussian blue cathodes, demonstrating its outstanding practicality.

Aqueous rechargeable Zn metal batteries (AZMBs) have attracted widespread attention due to their intrinsic high volumetric capacity and low cost. However, the unstable Zn/electrolyte interface causes Zn dendrite growth and side reactions, resulting in poor Coulombic efficiency and unsatisfactory lifespan. Herein, a SiO 2 reinforced-sodium alginate (SA) hybrid film is designed to regulate solid-liquid interaction energy and spatial distribution of all species in the electric double layer (EDL) near the Zn electrode. The unique interfacial layer gives rise to a uniform distribution of Zn 2+ in the Helmholtz layer through solvation sheath modulation. Moreover, theoretical calculations show that the SO 4 2− anions and free-water are substantially reduced in the Helmholtz layer, effectively suppressing hydrogen evolution reaction and formation of by-products through strong charge repulsion and hydrogen bond fixing of free-water. The reconfigured EDL not only ensures homogenous and fast Zn 2+ transport kinetics for dendrite-free Zn deposition, but also eliminates interface parasitic side reactions. The Zn@SiO 2 -SA electrode enables excellent cycling stability of symmetrical cells and high-loading full AZMBs with a lifespan over 3000 h and an areal capacity of 2.05 mAh cm −2 , thus laying a solid basis for realizing practical AZMBs.