Cooperative Effect of Redox Mediator and Ion Selective Membrane to Inhibit the Shuttle Effect for Li–O2 Battery with Large Cyclic Capacity

Abstract Aprotic lithium‐oxygen (Li–O 2 ) batteries hardly cycle at the condition of high area capacity for realizing their high energy density, because the unconducive lithium peroxide (Li 2 O 2 ) discharge product limits the electron transfer between electrode and O 2 /Li 2 O 2 . Here, it is demonstrated that one of redox mediator (RM), triethylene glycol bis‐2,2,6,6‐tetramethylpiperidin‐1‐oxyl radical (D‐TEMPO), can be effectively used to promote the electron transfer between electrode and Li 2 O 2 , which the shuttle effect of RM can be cooperatively inhibited by regulating the size of RM and the thickness of ion‐selective membrane. As a result, the Li–O 2 battery coupled with double cathodes, D‐TEMPO, and ion‐selective membrane can be stably operated for 46 days at a capacity of 5 mAh cm −2 . The concept in this work provides the cooperative design of a stable solution‐mediated pathway for high‐capacity Li–O 2 battery with long cycle stability.