Stabilizing Lithium Metal Batteries via Rapid EBID-Synthesized Lithiophilic Zinc Interfaces Regulating Lithium Deposition Behavior

Abstract

The uncontrolled growth of lithium dendrites has long been a major challenge hindering the commercial viability of lithium metal batteries.This issue is particularly prominent when using copper foil as the nucleation and deposition substrate due to its lithiophobicity and surface inhomogeneity, which accelerate dendrite growth. To regulate the lithium nucleation/deposition behavior and improve the surface properties of the andoe current collector, we utilized an Electron beam-induced deposition (EBID) system to rapidly synthesize a 200 nm thick lithiophilic zinc functional layer on the copper foil surface. The results showed that the rapid deposition effect based on EBID technology endows the zinc functionalized copper foil with an extremely low lithium nucleation overpotential (≈0 V) and abundant lithium nucleation site (C_dl=239.23 uF cm^-2). At the same time, the zinc layer has close to 100% mechanical bonding to the substrate. Compared to commercial copper foil, the current collector with a zinc-modified layer exhibits more uniform and controllable lithium deposition morphologies under various cycling numbers and lithium deposition capacities. Specifically, at a current density of 0.5 mA cm^-2, the half-cell assembled with this current collector maintains a Coulombic efficiency of up to 95% after 200 cycles, and the symmetric cell can stably cycle for over 3100 hours. This simple and efficient current collector design concept is instrumental in advancing the practical application of lithium metal batteries.