| abstract |
When a lithium-manganese-nickel-based oxide belonging to a spinel structure is used and used as a positive electrode active material for a non-aqueous electrolyte secondary battery, the secondary battery can be stably used even when charged and discharged to a high voltage. Provided is a lithium-containing composite oxide powder and a method for producing the same. The lithium-containing composite oxide powder of the present invention includes primary particles of single crystals composed of a lithium manganese nickel-based oxide containing at least lithium, manganese, and nickel and having a crystal structure belonging to a spinel structure. The average primary particle size, which is the average particle size, is 1 μm or more and 50 μm or less. The lithium-containing composite oxide powder of the present invention can be obtained by heating the metal-containing raw material and the lithium hydroxide at 900 ° C. or higher. [Selection] Figure 1 |