| abstract |
Provided is a positive electrode material for a lithium-ion cell comprising an excess-lithium layered lithium metal composite oxide that makes it possible to increase the volume energy density as an electrode and produce excellent rate characteristics. A positive electrode material for a lithium-ion cell comprising a lithium metal composite oxide having a layered structure represented by the following general formula: Li 1 + x Ma 1 - x - y Mb y O 2 (where x = 0.1 to 0.33, y = 0 to 0.3, Ma necessarily contains Mn and at least one element selected from Ni and Co, the Mn content of the Ma is 30-80 mass%, and Mb is at least one element selected from a group comprising Al, Mg, Ti, Fe, and Nb), wherein the positive electrode material for a lithium-ion cell is characterized in that the primary particle average grain size is at least 1.0 μm and the tap density is at least 1.9 g/cm 3 . |