17. Cathode active material for a non-aqueous electrolyte rechargeable battery comprising secondary particles that are formed by an aggregation of plural primary particles,
the cathode active material comprising layered hexagonal crystal lithium nickel manganese composite oxide particles that are expressed by the general expression (B): Li1+uNixMnyCozMtO2, where, −0.05≦u≦0.50, x+y+z+t=1, 0.3≦x≦0.95, 0.05≦y≦0.55, 0≦z≦0.4, 0≦t≦0.1, and M is one or more additional element that is selected from among Mg, Ca, Al, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W,
the secondary particles comprising a center section, and a hollow section where there are no primary particles, an outer-shell section that is electrically connected to the center section, and at least one inner-shell section between the hollow section and the outer-shell section on the outside of the center section; and
the secondary particles having an average particle size of 1 μm to 15 μm, and an index [(d90−d10)/average particle size] that indicates the extent of the particle size distribution of 0.7 or less.
the secondary particles
average particle size
1 μm to 15 μm
μm
the secondary particles
particle size distribution
0.7 or less