3. A nickel-based active material precursor according to claim 1 or claim 2, wherein:
the intermediate layer portion (20) and the shell portion (30) are each lower in porosity than the core portion (10), or the core portion (10) and the shell portion (30) are each higher in porosity than the intermediate layer portion (20); and/or
the nickel-based active material precursor has a mean particle diameter of about 9 µm to about 20 µm; and/or
the nickel-based active material precursor comprises plate particles, and
wherein major axes of the plate particles are radially arranged.
active material precursor
particle diameter
9 µm to about 20 µm
µm