Cathode material for lithium-ion secondary battery and method for manufacturing the same, cathode for lithium-ion secondary battery, and lithium-ion secondary battery

A cathode material for a lithium-ion secondary battery, the cathode material comprising:

• secondary particles which are granulated active material particles including central particles and a carbonaceous film that coats surfaces of the central particles, wherein
• a granulated body breakage degree ((a−b)/a) is 0.03 or more and 0.30 or less,
• the granulated body breakage degree is calculated based on a relative particle amount a, at which a maximum peak is shown in a particle size distribution of the secondary particles, and a relative particle amount b, at which a maximum peak in a particle size distribution of the secondary particles is shown after a dispersion treatment of the secondary particles is performed using a homogenizer, and
• the central particles are represented by general formula LixFeyMzPO4 (here, M represents at least one element selected from the group consisting of Mg, Ca, Co, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, and rare earth elements, 0.95 x 1.10, 0.80 y 1.10, and 0.00 z 0.20).