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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]

Garnet solid‐state electrolyte Li6.5La3Zr1.5Ta0.5O12 (LLZTO) holds significant promise. However, the practical utilization has been seriously impeded by the poor contact of Li|garnet and electron leakage. Herein, one new type of garnet‐based solid‐state battery is proposed with high performance through the disparity in interfacial energy, induced by the reaction between trace fluorinated carbon dots (FCDs) and Li. The work of adhesion of Li|garnet is increased by the acquired Li‐FCD composite, which facilitates an intimate Li|garnet interface with the promoted uniform Li+ deposition, revealed by density functional theory (DFT) calculations. It is further validated that a concentrated C−Li2O−LiF component at the Li|garnet interface is spontaneously constructed, due to the significant disparity in interfacial energy between C−Li2O−LiF|LLZTO and C−Li2O−LiF|Li. Furthermore, The electron transport and Li dendrites penetration are effectively hindered by the formed Li2O and LiF. The Li‐FCD|LLZTO|Li‐FCD symmetrical cells demonstrate stable cycling performance for over 3000 hours at 0.3 mA cm−2 and 800 hours at 0.5 mA cm−2. Furthermore, the LFP|garnet|Li‐FCD full cell exhibits remarkable cycling performance (91.6 % capacity retention after 500 cycles at 1 C). Our research has revealed a novel approach to establish a dendrite‐free Li|garnet interface, laying the groundwork for future advancements in garnet‐based solid‐state batteries. [ABSTRACT FROM AUTHOR]

The utilization rate of active sites in cathode materials for Zn‐based batteries is a key factor determining the reversible capacities. However, a long‐neglected issue of the strong electrostatic repulsions among divalent Zn2+ in hosts inevitably causes the squander of some active sites (i.e. gap sites). Herein, we address this conundrum by unraveling the "gap‐filling" mechanism of multiple charge carriers in aqueous Zn‐MoS2 batteries. The tailored MoS2/(reduced graphene quantum dots) hybrid features an ultra‐large interlayer spacing (2.34 nm), superior electrical conductivity/hydrophilicity, and robust layered structure, demonstrating highly reversible NH4+/Zn2+/H+ co‐insertion/extraction chemistry in the 1 M ZnSO4+0.5 M (NH4)2SO4 aqueous electrolyte. The NH4+ and H+ ions can act as gap fillers to fully utilize the active sites and screen electrostatic interactions to accelerate the Zn2+ diffusion. Thus, unprecedentedly high rate capability (439.5 and 104.3 mAh g−1 at 0.1 and 30 A g−1, respectively) and ultra‐long cycling life (8000 cycles) are achieved. [ABSTRACT FROM AUTHOR]

The structural failure of Na2Mn[Fe(CN)6] could not be alleviated with traditional modification strategies through the adjustable composition property of Prussian blue analogues (PBAs), considering that the accumulation and release of stress derived from the MnN6 octahedrons are unilaterally restrained. Herein, a novel application of adjustable composition property, through constructing a coordination competition relationship between chelators and [Fe(CN)6]4− to directionally tune the enrichment of elements, is proposed to restrain structural degradation and induce unconventional energy coupling phenomenon. The non‐uniform distribution of elements at the M1 site of PBAs (NFM‐PB) is manipulated by the sequentially precipitated Ni, Fe, and Mn according to the Irving‐William order. Electrochemically active Fe is operated to accompany Mn, and zero‐strain Ni is modulated to enrich at the surface, synergistically mitigating with the enrichment and release of stress and then significantly improving the structural stability. Furthermore, unconventional energy coupling effect, a fusion of the electrochemical behavior between FeLS and MnHS, is triggered by the confined element distribution, leading to the enhanced electrochemical stability and anti‐polarization ability. Consequently, the NFM‐PB demonstrates superior rate performance and cycling stability. These findings further exploit potentialities of the adjustable composition property and provide new insights into the component design engineering for advanced PBAs. [ABSTRACT FROM AUTHOR]