Efficient cycling of lithium (Li) metal batteries (LMBs) under extremely high current conditions is critical for their practical applications. Here, we report a novel additive containing fluorine, nitrogen, and iodine elements (designated as FCS) to stabilize Li metal anodes in glyme-based ether electrolytes under high current conditions. Experimental results and molecular dynamics (MD) simulations demonstrate that the cation of FCS selectively adsorbs on the electrode surface, optimizing the inner Helmholtz plane (IHP) structure and effectively regulating the surface electric field, thereby promoting homogeneous Li deposition. Simultaneously, the preferential decomposition of the FCS produces a mechanically robust and ionically conductive solid electrolyte interphase (SEI) comprising LiF, Li