POSITIVE-ELECTRODE ACTIVE MATERIAL FOR LITHIUM-ION CELL, POSITIVE ELECTRODE FOR LITHIUM-ION CELL, LITHIUM-ION CELL, AND METHOD FOR MANUFACTURING POSITIVE-ELECTRODE ACTIVE MATERIAL FOR LITHIUM-ION CELL

摘要

Provided is a positive-electrode active material for a lithium-ion cell having excellent cell characteristics. A positive-electrode active material for a lithium-ion cell, the positive-electrode active material being represented by the composition formula LixNi1 - (y + z)MnyCozO2 + α (in the formula, 0.9 ≤ x ≤ 1.2, 0 < y + z ≤ 0.3, -0.1 ≤ α ≤ 0.1), the average particle diameter D50 being 5-7 μm, the particle strength being 60 MPa or higher, and the average voidage in the interior of particles having a particle diameter of 3 μm or more being 5% or less.