High‐Entropy Interfacial Optimized 3D Nano‐Collector Enables Dendrite‐Free and Ultra‐Stable Lithium Metal Batteries

Lithium metal batteries (LMBs) are regarded as one of the most promising candidates for next‐generation high‐energy‐density storage systems. However, their application is severely hindered by the uncontrollable lithium dendrite growth and unstable solid electrolyte interphases formation on conventional planar Cu current collectors. To address these challenges, we propose a synergistic interphase–structure modification strategy that integrates a MnNiVCrFe high‐entropy alloy (HEA) interphase with a three‐dimensional (3D) nanoflower (NF) scaffold. The 3D NF scaffold offers spatial confinement to guide uniform lithium deposition, while the HEA interphase provides abundant lithiophilic nucleation sites and intrinsic magnetic regulation. By homogenizing the interfacial electric field and Li + distribution, this dual modification enables uniform lithium nucleation and deposition, thereby suppressing dendrite formation and boosting interfacial stability. The resulting the HEA/NF@Cu electrode delivers remarkable cycling stability, exceeding 670 cycles with a high average Coulombic efficiency of 98.5% at 0.5 mA cm −2 , and the corresponding symmetric cells achieve an ultralong lifespan of 6270 h under the same current density. This synergistic interphase–structure engineering strategy provides a promising solution for designing advanced current collectors toward stable and dendrite‐free LMBs.