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An advance Li‐sphere possessing a definitely regular morphology in Li deposition enables a well‐defined more robust structure and superior solid‐electrolyte interphase (SEI) to achieve high‐efficiency long‐term cycles in Li metal anode. Here, a new sight of high Li+ cluster‐like solvation sheaths coordinated in a localized high‐concentration NO3− (LH‐LiNO3) electrolyte fully clarifies for depositing advanced Li spheres. Moreover, we elucidate a critical amorphous‐crystalline phase transition in the nanostructure evolution of Li‐sphere deposits during the nucleation and growth. Li‐sphere anode exhibits ultra‐stable structural engineering for suppressing Li dendrite growths and rendering ultralong life of 4000 cycles in symmetrical cells at 2 mA cm−2. The as‐constructed Li spheres/3DCM|LiFePO4 (LFP) full cell delivers a high capacity retention of 90.5% at 1 C after 1000 cycles, and a robust dendrite‐free structure also stably exists in Li‐sphere anode. Combined with high‐loading LFP cathodes (6.6 and 10.9 mg cm−2), superb capacity retentions are up to 96.5% and 92.5% after 800 cycles at 1 C, respectively. Cluster‐like solvation sheaths with high Li+ coordination exert significant influence on depositing a high‐quality Li‐sphere anode. [ABSTRACT FROM AUTHOR]

A disordered phase in Li‐deposit nanostructure is greatly attractive, but plagued by the uncontrollable and unstable growth, and the nanoscale characterization in the structure. Here, fully characterized in cryogenic transmission electron microscopy (cryo‐TEM), more robust amorphous‐Li (ALi) clusters are revealed and effectively regulated on heteroatom‐activating electronegative sites and an advanced solid electrolyte interphase (SEI) layer. Heteroatom‐activating electronegative sites capably enhance the electrostatic interaction of Li+ and heteroatom‐doping graphene‐like film (HDGs), meaning lower Li diffusion barrier and larger binding energy that is confirmed by small nucleation overpotentials of 13.9 and 10 mV at 0.1 mA cm−2 in the fluoroethylene carbonate‐adding ester‐based (FEC‐ester) and LiNO3‐adding ether‐based (LiNO3‐ether) electrolytes. Orderly multilayer SEI structure comprised of inorganic‐rich components enables fast ion transports and durable capabilities to construct highly reversible and long‐term plating/stripping cycling. ALi cluster anodes exhibit non‐crystalline morphologies and perform ultrastable dendrite‐free cycling over 2800 times. Stable ALi clusters are also grown in LiFePO4 (LFP) (LFP‐ALi‐HDGs‐N||LiFePO4 [LFP]) full cells with advantageous capacities up to 165.5 and 164.3 mAh g−1 in these optimized electrolytes at 0.1 C; the remarkable capacity retentions maintain to 93% and 91% after 150 cycles at 0.2 C. Structure viability, electrochemical reversibility, and excellent performance in ALi clusters are effectively regulated. [ABSTRACT FROM AUTHOR]