Construction of a Magnetic Interphase for Stable Cycling of Lithium Metal Batteries

Abstract Lithium (Li) metal has been considered to be the most promising anode material. However, the uncontrolled growth of Li dendrites and the instability of the solid electrolyte interphase (SEI) plague the commercial application of Li anodes. In this paper, a dual‐functional artificial magnetic interphase composed of PVDF and γ‐Fe₂O₃ is designed and constructed on the anode surface. The magnetic interphase modulates the distribution of lithium ions near the interface to induce stable deposition and stripping processes. Meanwhile, the magnetic particles improve the mechanical properties of the SEI layer and suppress the growth and spread of Li dendrites. The symmetrical cell coated with the magnetic layer has a stable cycle life of more than 4000 hours which is longer than that reported in most literature under the same conditions. This study highlights the significance of the magnetic field in stabilizing lithium metal anodes, providing new insights and approaches to develop efficient batteries by matching the diffusion and reaction processes in batteries.