Electronegative Nanochannels Accelerating Lithium‐Ion Transport for Enabling Highly Stable and High‐Rate Lithium Metal Anodes

Abstract Achieving a high Li + transference number is an effective strategy to inhibit the nucleation of lithium dendrites on the metal anode according to classical Sand's time principle. However, improving the Li + transference number usually causes aloss of ionic conductivity of lithium metal batteries. Here, inspired by biological ion channels tuning ion transport, an electronegative nanochannels separator is developed to accelerate Li + transport for enabling dendrite‐free and high‐rate lithium metal anodes. Benefiting from selective and fast Li + transport, the electronegative nanochannels separator can simultaneously achieve high Li + transference number (0.77) and high Li + conductivity (1.36 mS cm −2 ) within a liquid lithium metal battery. Such an optimization of Li + transport dynamics can significantly prolong the nucleation time of lithium dendrite and thus effectively suppress dendritic growth, which contributes to an extremely stable Li plating/stripping cycling for over 2000 h at a high current density of 5 mA cm −2 . When assembled into lithium metal batteries, the electronegative nanochannels separator enables superior comprehensive electrochemical performance compared with the commercial polyolefin one. This work provides new insights into the design of functional separators toward dendrite‐free and high‐rate liquid lithium metal batteries.