Composite hydroxides and their manufacturing methods, and positive electrode active materials using composite hydroxides and their manufacturing methods.

Abstract

The composite hydroxide of this invention contains nickel (Ni) and manganese (Mn) elements. The oil absorption of the composite hydroxide, measured according to JIS K 5101:2004, is 3.0 mL / 5 g or more and 6.5 mL / 5 g or less. The density of the composite hydroxide, measured by the gas displacement method, is preferably 4.00 g / cm³ or more and 4.99 g / cm³ or less. The cumulative volumetric particle size of the composite hydroxide, obtained by laser diffraction particle size distribution determination at 50% volume, is preferably 3.0 μm or more and 20.0 μm or less. The BET specific surface area of ​​the composite hydroxide is preferably 15.0 m² / g or more and 65.0 m² / g or less.