Electronic structures of partially fluorinated lithium manganese spinel oxides and their electrochemical properties

Abstract Partially fluorinated lithium manganese spinel oxides (LiMn 1.8 Li 0.1 Ni 0.1 O 4− x F x ) were prepared by solid-state reaction. Relationship between the electronic structures of LiMn 1.8 Li 0.1 Ni 0.1 O 4− x F x and their electrochemical properties were investigated. X-ray absorption near-edge structure (XANES) of Mn K-edge showed that the absorption edge shifted to lower energy with increasing F − content, which indicated decrease of the Mn average oxidation state. Discharge capacity at first cycle was increased by decrease of the Mn average oxidation state with increasing F − content.