POSITIVE-ELECTRODE ACTIVE MATERIAL POSITIVE ELECTRODE BATTERY BATTERY PACK ELECTRONIC DEVICE ELECTRIC VEHICLE ELECTRICITY STORAGE APPARATUS AND POWER SYSTEM

摘要

The positive electrode active material has secondary particles in which a plurality of primary particles are aggregated. The primary particles include a core particle containing a lithium composite oxide and a layer formed on the surface of the core particle and including a lithium composite oxide. The lithium composite oxide contained in the core particles and the lithium composite oxide contained in the layer have the same composition or almost the same composition. The crystallinity of the lithium composite oxide contained in the layer is lower than that of the lithium composite oxide contained in the core particle.