Lithium-ion secondary battery, battery apparatus, and electric apparatus

Abstract

The present disclosure provides a lithium-ion secondary battery, a battery apparatus, and an electric apparatus. The lithium-ion secondary battery includes: a positive electrode plate. The positive electrode plate includes a positive electrode current collector and a positive electrode film layer disposed on at least one side of the positive electrode current collector. The positive electrode film layer includes a positive electrode active material. The positive electrode active material includes a lithium-transition metal phosphate particle. The lithium-transition metal phosphate particle includes a lithium-transition metal phosphate matrix and a coating on at least part of a surface of the lithium-transition metal phosphate matrix. The coating includes the carbon element. In a cross section of the positive electrode film layer along a thickness direction of the electrode plate, the proportion of the number of Particles I having a particle size of less than 300 nm is 60% to 70% based on the total number of the lithium-transition metal phosphate particles. The average particle size of Particles III with a particle size of greater than 1.5 μm is less than or equal to 2.6 μm. The lithium / iron antisite defect concentration of the positive electrode active material is less than or equal to 3.6%.