[SIS11] Energy Materials

[16D-SIS11-02] Composition Dependencies of Positive Electrode Properties and Local Structures of Li_1+xNbxFe_1-2xO₂ with a Disordered Rocksalt Structure

*N. Kitamura¹, R. Kure¹, C. Ishibashi¹, Y. Idemoto¹ (1.Tokyo University of Science, Japan)

キーワード：Lithium ion battery, Positive electrode, Local structure

Powders of lithium-rich transition metal oxide Li_1+xNb_xFe_1-2xO₂ with a disordered rocksalt structure (NaCl-type structure) have attracted much attention as positive electrode materials for next-generation lithium-ion batteries. However, the atomic arrangements of these materials remain unclear, and their relationship with positive electrode properties has not been clarified. In this study, the composition dependence of the atomic arrangement of Li_1+xNb_xFe_1-2xO₂ (x = 0.05-1.25) is investigated by analyzing the pair distribution functions (PDFs) obtained by X-ray total scattering measurements. As a result, it was indicated that NbO₆ octahedra had smaller volume than the other octahedra and thus the Li⁺ diffusion paths were wider in the vicinity of Nb.