Lithium metal composite oxide, positive electrode active substance for lithium secondary battery, positive electrode for lithium secondary battery, lithium secondary battery, and method for producing lithium metal composite oxide

Abstract

A lithium metal composite oxide having a layered structure, including at least lithium and an element X, wherein:the element X is at least one element selected from the group consisting of Co, Mn, Fe, Cu, Ti, Mg, Al, W, Mo, Nb, Zn, Sn, Zr, Ga, V, B, Si, S and P; the lithium metal composite oxide contains single particles and satisfies all of requirements (1) to (5):(1): a volume-based 50% cumulative particle size Dof the lithium metal composite oxide is 2 μm or more and 10 μm or less; (2): the single particles have, on at least a part of surfaces thereof, adhered fine particles, with the proviso that a maximum particle size of the adhered fine particles is smaller than a particle size of the single particles; (3): the particle size of the single particles is 0.2 to 1.5 times Dof the lithium metal composite oxide; (4): a particle size of the adhered fine particles is 0.01 to 0.1 times the Dof the lithium metal composite oxide; and (5): an average number of the adhered fine particles adhered per particle of the single particles is 1 or more and 30 or less as measured with respect to a range observable in an image obtained by scanning electron microscope.