Patent ID: 9040199
Filing Date: 2015-05-26
Classification: B82Y,C01P,H01M,Y02E

Abstract:
1. Positive electrode active material particles for lithium ion secondary batteries, the particles each comprising: a core particle; and a shell layer attached to the surface of the core particle, wherein the core particle comprises a first olivine-structured, lithium-containing phosphate compound including: at least one metal element selected from the group consisting of Fe and Mn; and Li, the shell layer comprises a second olivine-structured, lithium-containing phosphate compound including: at least one metal element selected from the group consisting of Fe and Mn; and Li, at least the core particle includes a phosphorous compound represented by the following formula (1): where Me is at least one metal element selected from the group consisting of Fe and Mn, 0<m≦3, 0<n ≦3, and 0≦p≦5, a content C1 of the phosphorous compound relative to the total moles of the first olivine-structured, lithium-containing phosphate compound and the phosphorous compound in the core particle, is 0.5 to 3 mol %, and in the case where the shell layer includes the phosphorous compound represented by the formula (1), a content C2 of the phosphorous compound relative to the total moles of the second olivine-structured, lithium-containing phosphate compound and the phosphorous compound in the shell layer, is smaller than the content C1.