Preparation of cathode active materials for lithium ion secondary batteries utilizing microwave irradiation: Part II. Electronic structure of lithium manganese oxide

The microwave irradiation technique (MWIT) was applied to synthesize lithium manganese oxide having spinel structure using LiOH·H2O and ε–MnO2 as starting materials. The crystal and electronic structure depends on the irradiation time; x-ray diffraction patterns of the sample irradiated for 9 min were in good agreement with that of cubic structure without showing the peak of MnO2. The electronic structure of synthesized samples before and after lithium ion intercalation and/or deintercalation was investigated by Mn L-edge and O K-edge x-ray absorption spectroscopy.