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Lithium (Li) metal anodes have been proposed as a promising candidate for high‐energy‐density electrode materials in secondary batteries. However, the dendrite growth and unstable electrode–electrolyte interfaces during Li plating/stripping are fatal to their practical applications. Herein, the construction of 3D porous Au/Cu nanoscaffold prepared via a convenient template‐sacrificed hot fusion construction method and a nanoseed modification process as an effective Li metal hosting material are proposed. The Au/Cu nanoscaffold can spatially guide uniform deposition of Li metal free from the growth of Li dendrites due to the homogenous Li+ ion flux and negligible nucleation overpotential. Moreover, the Cu skeleton can relieve volume change and stabilize local current density during cycling processes. Benefiting from these advantages, the symmetric cells based on self‐supported Li‐filled Au/Cu (Li‐Au/Cu) nanoscaffold electrodes present highly stable Li plating/stripping for more than 1000 h with a low voltage hysteresis less than 90 mV and a long lifespan over 1300 h at 1.0 mA cm–2 in carbonate‐based electrolytes. Impressively, the Li‐Au/Cu nanoscaffold||LiFePO4 full cells also exhibit exceptional cycling stability and rate performance. This work provides a promising strategy to construct dendrite‐free lithium metal anodes toward high‐performance lithium metal batteries. [ABSTRACT FROM AUTHOR]

Layered transition metal (TM) oxides of the stoichiometry NaxMO2 (M = TM) have shown great promise in sodium‐ion batteries (SIBs); however, they are extremely sensitive to moisture. To date, most reported titanium‐based layered anodes exhibit a P2‐type structure. In contrast, O3‐type compounds are rarely investigated and their synthesis is challenging due to their higher percentage of unstable Ti3+ than the P2 type. Here, a pure phase and highly crystalline O3‐type Na0.73Li0.36Ti0.73O2 with high performance is successfully proposed in SIBs. This material delivers a reversible capacity of 108 mAh g−1 with a stable and safe potential of 0.75 V versus Na/Na+. In situ X‐ray diffraction reveals that this material does not undergo any phase transitions and exhibits a near‐zero volume change upon Na+ insertion/de‐insertion, which ensures exceptional long cycle life over 6000 cycles. Importantly, it is found that this O3‐Na0.73Li0.36Ti0.73O2 shows superior moisture stability, even when immersed into water, which are both elusive for conventional layered TM oxides in SIBs. It is believed that the small interlayer distance and high occupation of interlayer vacancy promise such unprecedented water stability. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal anodes have long been counted on to meet the increasing demand for high energy, high‐power rechargeable battery systems but they have been plagued by uncontrollable plating, unstable solid electrolyte interphase (SEI) formation, and the resulting low Coulombic efficiency. These problems are even aggravated under commercial levels of current density and areal capacity testing conditions. In this work, the channel‐like structure of a carbonized eggplant (EP) as a stable "host" for Li metal melt infusion, is utilized. With further interphase modification of lithium fluoride (LiF), the as‐formed EP–LiF composite anode maintains ≈90% Li metal theoretical capacity and can successfully suppress dendrite growth and volume fluctuation during cycling. EP–LiF offers much improved symmetric cell and full‐cell cycling performance with lower and more stable overpotential under various areal capacity and elevated rate capability. Furthermore, carbonized EP serves as a light‐weight high‐performance current collector, achieving an average Coulombic efficiency ≈99.1% in ether‐based electrolytes with 2.2 mAh cm−2 cycling areal capacity. The natural structure of carbonized EP will inspire further artificial designs of electrode frameworks for both Li anode and sulfur cathodes, enabling promising candidates for next‐generation high‐energy density batteries. An interconnected channel‐like framework originating from eggplant is introduced to serve as a stable host for lithium (Li) metal anodes. Coulombic efficiency of 99.1% is achieved when directly using the framework as current collector. Minimal volume fluctuation, suppressed dendrite growth, and improved rate capability are realized when Li metal is melt infiltrated into the framework to form a composite anode. [ABSTRACT FROM AUTHOR]