POSITIVE ELECTRODE ACTIVE MATERIAL FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERIES, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

A positive electrode active material for nonaqueous electrolyte secondary batteries includes secondary particles of lithium transition metal oxide including aggregates of primary particles of the oxide. The primary particles have an average particle size of not less than 1 μm, and the secondary particles have a void content of more than 30%.