A reaction-dissolution strategy for designing solid electrolyte interphases with stable energetics for lithium metal anodes

The spatial variations in chemical composition and transport properties of the interphase formed on reactive metal electrodeposits dictate the stability and reversibility of electrochemical cells that use reactive metals as anodes. Here we report on the influence of carbonate and fluorinated electrolytes infused with ethers as additives on the physical-chemical characteristics and reversibility of metallic lithium (Li) during early stages of electrodeposition and later stages of deep cycling of Li metal anodes. We show that a feasible strategy for achieving and sustaining kinetically enhanced interphases through the cycle life of Li electrodeposits is by simultaneous use of sacrificial electrolyte components that undergo electroreduction to enrich the interphase with fluorinated species in tandem with cleaning electrolyte components that promote dissolution and removal of less desirable carbonaceous compounds. We demonstrate that this approach translates to high electrochemical reversibility during deep cycling of the Li metal anode and improved performance of Li metal batteries.