Caging Lithium Deposition: High-Entropy Metal-Organic Framework Interfaces for Anode-Free Batteries

Anode-free lithium metal batteries (AF-LMBs) offer high energy density systems and simplified design through the complete elimination of excess lithium. However, their practical development is hindered by sluggish lithium-ion (Li⁺) transport and uneven lithium deposition at the anode interface. Here, we introduce a nanoconfined ion-regulator based on a high-entropy metal-organic framework (HE-MOF). The simulation results demonstrate that the multi-metal channels provide heterogeneous local coordination environments, broadening the distribution of Li⁺ binding sites, facilitating Li⁺ migration, suppressing local ion retention, and regulating interfacial electrolyte decomposition, ultimately leading to the formation of a thin LiF-rich SEI layer. As a result, the Li||HE-MOF/C half-cell delivers an initial Coulombic efficiency of 97.74% at 0.5 mA cm^-2, the HE-MOF/C@Li symmetric cell exhibits stable cycling for over 10000 h at 60 mA cm^-2/1 mAh cm^-2, and the anode-free HE-MOF/C||NCM-811 full cell remains stable for 2300 cycles with a capacity decay rate per cycle of 0.026%. This work provides a proof-of-concept high-entropy MOF interfacial strategy for regulating Li deposition in AF-LMBs.