Organic Cationic-Coordinated Perfluoropolymer Electrolytes with Strong Li-Solvent Interaction for Solid State Li-Metal Batteries.

The practical application of solid-state polymer lithium-metal batteries (LMBs) is plagued by the inferior ionic conductivity of the applied polymer electrolytes (PEs), which is caused by the coupling of ion transport with the motion of polymer segments. Here, solvated molecules based on ionic liquid and lithium salt with strong Li-solvent interaction are inserted into an elaborately engineered perfluoropolymer electrolyte via ionic dipole interaction, extensively facilitating Li transport and improving mechanical properties. The intensified formation of solvation structures of contact ion pairs and ionic aggregates, as well as the strong electron-withdrawal properties of the F atoms in perfluoropolymers, give the PE high electrochemical stability and excellent interfacial stability.