▎ 摘　　要

NOVELTY - The battery has a positive electrode active material which has a first region and a second region provided inside the first region. The positive electrode active material has lithium, oxygen, nickel, cobalt and manganese. The concentration of one of the nickel, the cobalt, and the manganese differs between the first region and the second region. The positive electrode active material has an impurity layer having an impurity element. The impurity element is titanium, fluorine, magnesium, aluminum, zirconium, calcium, gallium, niobium, phosphorus, boron, and silicon. The secondary battery has a carbon material which is fibrous carbon, graphene, and particulate carbon. USE - Secondary battery e.g. lithium ion secondary battery and coin-type secondary battery using positive electrode active material for electronic devices, such as TV apparatus e.g. TV receiver or TV receiver, vehicles (all claimed), building and moving object e.g. automobile. Can also be used for monitor such as computer, digital camera, digital video camera, digital photo frame, mobile phone or cellular phone, portable game machine, portable information terminal, acoustic reproduction device, and large-sized game machine such as pachinko machine, next-generation clean energy vehicle such as hybrid vehicle (HV), electric vehicle , or plug-in hybrid vehicle, train, monorail, ship, flying object e.g. helicopter, unmanned aerial vehicle e.g. drone, airplane, rocket, electric bicycle, and electric motorcycle, microwave oven, refrigerator, or air conditioner. ADVANTAGE - The positive electrode active material having a high energy density and a large charge/discharge capacity can be provided. The positive electrode active material having little deterioration can be provided. The secondary battery having a large charge/discharge capacity can be provided. The secondary battery having high safety or reliability can be provided. The secondary battery with less deterioration can be provided. The secondary battery having a long service life can be provided. DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of the positive electrode active material. Particle (190) Regions (191-193)