| 摘要 |
Provided is a positive active material which, when used to configure a positive electrode for lithium secondary batteries, has a high volumetric energy density and, despite this, renders high rate characteristics possible. This positive active material comprises multiple secondary particles each composed of many primary particles constituted of a lithium-nickel composite oxide having a layered rock-salt structure. The multiple secondary particles have a volume-average particle diameter D50 of 5-100 µm, and some of the secondary particles are coarse secondary particles having a particle diameter of 9 µm or larger. The coarse secondary particles have a porosity of 5-25%, and 70% or more of all the voids of the coarse secondary particles are accounted for by through-holes. |
