An amorphous LiO2-based Li-O2 battery with low overpotential and high rate capability

Replacing Li2O2 with LiO2 as the discharge product is a very promising strategy to tackle the problems of high overpotential(similar to 1.5 V), inferior rate capability and short cycle life in the current Li-O-2 batteries based on Li2O2. But it's very difficult to control LiO2 due to its thermodynamic instability. Herein, we have successfully built a facile rechargeable Li-O-2 battery based on the formation and decomposition of amorphous LiO2 with an ultralow overpotential(similar to 0.3 V), long cycle life and high rate capability under the catalysis of 3D-architectured Pd-rGO. In-situ Raman spectrum, linear sweep voltammetry, UV-vis measurements and SAED( Selected Area Electron Diffraction) all have identified the amorphous LiO2-based electrochemical process. Amorphous LiO2 shows a lower oxidation potential and a faster ionic conductivity contributing to the excellent electrochemical performances and the mitigation of undesirable side reactions. This study opens a new horizon to solve the intrinsic problems of the current Li-O-2 batteries.