Lithium-manganese composite oxide and method for producing same, and positive electrode material, positive electrode and lithium ion secondary battery using same

Abstract

A lithium-manganese composite oxide containing a lithium-iron-manganese composite oxide represented by the composition formula: Li1+x−w(FeyNizMn1−y−z)1−xO2−δ, where 0<x<⅓, 0≤w<0.8, 0<y<1, 0<z<0.5, y+z<1, and 0≤δ<0.5, in which at least in a state of charge of a lithium ion battery using the lithium-manganese composite oxide as a positive-electrode active material, at least some of iron atoms are pentavalent.

Dependencies are inferred from the claim text.