Suppression of electrolyte decomposition and protection of the lithium metal anode via a lactone additive

Incorporation of 1,4-dioxane-2,5-dione (1,4-DD) into commercial carbonate-based electrolytes effectively suppresses solvent decomposition in lithium metal batteries. This effect arises from the preferential ring-opening polymerization of 1,4-DD, which precedes electrolyte degradation and leads to the formation of poly(1,4-DD). The resulting polymeric film acts as a protective interphase on the lithium metal anode, enhancing interfacial stability.