Reacquainting the Sudden-Death and Reaction Routes of Li-O2 Batteries by Ex-Situ Observation of Li2O2 Distribution Inside a Highly Ordered Air Electrode

This work designs a carbon-coated anodic aluminum oxide(C-AAO) air electrode with a highly ordered array structure, revealing the Li2O2 distribution inside the real air electrode and not limited to the electrode surface. Based on this, the transport mechanism of Li-O2 batteries is further investigated: The sudden death is a coupled result of charge transfer impedance and concentration polarization. The growth model of Li2O2 is proposed and the dependence of toroidal Li2O2 on the electrode surface is explained. This work provides a reference for understanding the operating mechanism and Li-O2 battery design.

September 2022