US 12,183,928 B2 · Positive electrode active material

Abstract

To provide a positive electrode active material capable of improving cycle characteristics of a lithium ion secondary battery and achieving a desirable discharge capacity. A positive electrode active material that is an aggregate of lithium compounds each including a lithium-containing transition metal oxide, includes particles having a surface on which a solid film including a plurality of types of lithium salts is formed. The solid film preferably includes a fluorine compound and a phosphorus compound. The solid film preferably contains 70 mol % or more of fluorine atoms with respect to the total number of moles of the fluorine atoms and phosphorus atoms.

Claims4

Dependent claims

A positive electrode active material that is an aggregate of lithium compounds each comprising a lithium-containing transition metal oxide,

the positive electrode active material comprising particles having a surface on which a solid film comprising lithium fluoride (LIF) and lithium metaphosphate (LIPO3) is formed,
the solid film having a thickness of 30 nm or more and 70 nm or less,
wherein the thickness of the solid film means a maximum thickness of the solid film with respect to the surface of the particles of the positive electrode active material when a perpendicular line is drawn to a center of the positive electrode active material, and
wherein the solid film contains 70 mol % or more of fluorine atoms with respect to a total number of moles of the fluorine atoms and phosphorus atoms.

1 more element

Dependencies are inferred from the claim text.

Positive electrode active material

Life of this patent

Positive electrode active material

Life of this patent

Abstract

Claims4