MANUFACTURING METHOD OF CATHODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY

PROBLEM TO BE SOLVED: To provide a method of manufacturing a cathode active material capable of configuring a lithium ion secondary battery which contains olivine type iron phosphate particles and has excellent characteristics.SOLUTION: According to a manufacturing method of a cathode active material for a lithium ion secondary battery containing olivine type iron phosphate particles, the cathode active material does not form a secondary aggregate but is present as a single particle. An average particle size of the olivine type iron phosphate particles is settled within the range of 5 to 50 nm, and a particle size of particles in 90% or more of all the particles is settled within the range of 3 to 70 nm. Iron oxide particles having the average particle size of 50 nm or less are used for growth nucleus, the iron oxide particles are mixed with a solution containing a lithium source and a phosphate source, and a resultant mixture is heated.