Decoupling Energy Storage from Electrochemical Reactions in Li–Air Batteries toward Achieving Continuous Discharge

Intrinsic performance issues in Li–air batteries, such as poor reversibility and power, result from multiple functions at the cathode. Electrochemical reactions and discharge product storage are two such contradictory functions that interfere with each other. Here, we propose a new concept Li–air battery that can decouple those functions via simple yet drastic changes in the electrolyte composition, completely eliminating Li⁺ ions in the area around the cathode using an ionic liquid. The Li⁺-free environment for the cathode reaction realizes continuous discharge, in similar fashion to fuel cells, for more than 1000 h due to its unique concept of storing generated Li₂O₂ in the bulk electrolyte. The new concept opens an avenue to redesign Li–air battery systems with wide flexibility to balance power and capacity independently and efficiently.