Dual-function redox mediator enhanced lithium-oxygen battery based on polymer electrolyte

The polymer electrolyte based lithium-oxygen battery has showed higher safety than that of organic liquid electrolyte. However, the energy efficiency and cycling stability are still the challenges for the practical application of lithium-oxygen battery. Herein, the 1,4 para benzoquinone has been demonstrated as dual-function redox mediator for promoting both oxygen reduction and oxygen evolution reactions of lithium-oxygen battery with polymer electrolyte, which have been confirmed by the Cyclic Voltammetry and discharge/charge test of battery under O2 gas, as well as the theoretical calculations. Furthermore, the composite cathode that in-situ constructed by polymerizing electrolyte precursors with redox mediator can be beneficial for the electrochemical reactions. Combing composite cathode and lithium ions source, the polymer electrolyte based lithium-oxygen batteries can operate for long lifetime with low charge potentials and good rate performances. Thus, this work has highlighted the promising implementation of lithium-oxygen battery based on polymer electrolyte, in which the dual-function redox mediator are employed for both discharge and recharge processes.