Solid Electrolyte Interphase Layers by Using Lithiophilic and Electrochemically Active Ionic Additives for Lithium Metal Anodes

The use of role-assigned ionic additives with different adsorption energies and distinct electron-accepting abilities enables the construction of a multilayer solid electrolyte interphase (SEI) with a sequential structure of lithiophilic, mechanically robust, and ion-permeable layers on Li metal anodes. The uncontrollable Li dendrite formation, which is promoted by localized electric fields on the Li metal anode, is suppressed by the lithiophilic Ag-containing inner SEI and LiF + Li₃N-enriched outer SEI with reduced overpotentials upon Li deposition.