Biomimetic Ion Channel Design for Simultaneous Lithium‐Ion Flux Regulation and Interfacial Stabilization in Lithium Metal Batteries

ABSTRACT Lithium metal batteries hold great promise for future energy storage due to their high energy density and potential for fast charging, making them ideal for applications in electric vehicles and portable electronics. However, lithium metal batteries usually suffer from rapid performance degradation because of the unstable electrode/electrolyte interface. To address this, we integrate bionic ion channels into commercial battery separators. This structure features metal–organic framework (MOF)‐encapsulated benzo‐12‐crown‐4‐ether, mimicking biological ion channels. It enables rapid Li ⁺ transport and uniform flux distribution, which suppress lithium dendrite growth. The crown ether sites in bionic ion channels weaken Li ⁺ ‐solvent coordination, forming an anion‐rich solvation sheath. These anions preferentially decompose, generating a passivation layer at the anode interface that is rich in inorganic LiF and Li ₃ N. Consequently, Li||Li symmetric cells achieve stable plating/stripping for over 1500 h, and LiFePO ₄ ||Li full cells retain 86% capacity after 1200 cycles. This work provides a promising strategy for synergistic regulation of Li ⁺ flux and interfacial chemistry through bionic design.