A new phosphonamidate as flame retardant additive in electrolytes for lithium ion batteries

► We synthesized a new N-P collaborative flame retardant additive for lithium ion batteries (LIBs). ► The additive can provide a wide electrochemical stability window. ► The electrolytes with and without DEMEMPA have similar electrochemical behavior with natural graphite and LiFePO4 electrodes. ► The additive acts as a Lewis base, which enhances the stability of the electrolyte.