(357a) All Solid State Rechargeable Lithium-Air Batteries Using Block Copolymers

The growing need for alternative energy and increased demand for mobile technology require higher density energy storage. Existing battery technologies, such as lithium ion, are limited by theoretical energy density as well as safety issues. Other battery chemistries, such as lithium-air, are promising options for dramatically increasing energy density. Safety can be improved by replacing the flammable, reactive liquids used in existing lithium-ion battery electrolytes with polymer electrolytes. Block copolymers are uniquely suited for this task because ionic conductivity and mechanical strength, both important properties in battery formulation, can be independently controlled. In this study, lithium-air batteries were assembled using lithium metal as negative electrode, polystyrene-b-poly(ethylene oxide) copolymer with lithium salt as electrolyte, and a porous positive electrode. The positive electrode consisted of polymer electrolyte for ion conduction, carbon for electron conduction, and manganese dioxide as catalyst. Batteries were charged and discharged over many cycles. The battery cycling results were compared to a more conventional battery chemistry, lithium iron phosphate. To our knowledge, this is the first demonstration of an all solid state rechargeable lithium-air battery.