Recent Progress in Applying In Situ/Operando Characterization Techniques to Probe the Solid/Liquid/Gas Interfaces of Li–O2 Batteries

TLDR: In this paper, recent progress in applying in situ/operando characterization techniques to probe the solid/liquid/gas interfaces of Li-O2 batteries is reviewed, the working principle and experimental designs of these in situ and operando techniques are discussed, the critical mechanistic insights revealed, and how these studies advance the fundamental development of Li−O2 battery considered.

Abstract: Lithium–oxygen (Li–O2) batteries have attracted intensive attention owing to their potential to provide gravimetric energy density 2–5 times that of conventional Li-ion batteries. However, Li–O2 technology suffers from poor cycle life, low rate capability, and poor round-trip efficiency. Insights into the Li–O2 reaction mechanisms are prerequisites to breakthroughs in Li–O2 battery technology. Here, recent progress in applying in situ/operando characterization techniques to probe the solid/liquid/gas interfaces of Li–O2 batteries is reviewed. The working principle and experimental designs of these in situ/operando techniques are discussed, the critical mechanistic insights revealed, and how these studies advance the fundamental development of Li–O2 batteries considered.