| abstract |
In a layer structure oxide in crystallite form having a composition of the formula: AMO₂ wherein A is Li or Na and M is Co, Ni, Fe or Cr, at least one additive element Z which is Bi, Pb or B is present in the form of an oxide on the surface of crystallites or between crystallites. Atomic ratio Z/M is from 0.0001 to 0.1. Since the crystallites have an increased size, the layer structure oxide has improved properties and is suitable for use as a positive electrode material of a secondary cell. |