POSITIVE ELECTRODE ACTIVE MATERIAL, SECONDARY BATTERY, AND ELECTRIC DEVICE

A positive electrode active material, a secondary battery, and an electric device are disclosed. The positive electrode active material satisfies the following relationship: 300≤P*D/Δθ≤800; where P represents the porosity of the positive electrode active material, with a unit of %; D represents the crystal plane dimension of the (110) crystal plane of the positive electrode active material, with a unit of Å; and Δθ represents a splitting degree between a diffraction angle of the (110) crystal plane and that of (108) crystal plane of the positive electrode active material, with a unit of °.