Positive electrode for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery using the positive electrode

摘要

It is an object of the present invention to provide a positive electrode for nonaqueous electrolyte secondary batteries that can suppress decreases in the discharge capacity and discharge voltage even when continuous charging is performed at high temperature and that can also suppress decreases in the discharge voltage and energy density even in the charge and discharge after the continuous charging, and to provide a nonaqueous electrolyte secondary battery that uses the positive electrode. The positive electrode includes a positive electrode active material composed of a mixture containing lithium cobalt oxide 21 having a surface to which an erbium compound 22 is partly adhered and lithium nickel cobalt manganese oxide and a binder. The content of the lithium nickel cobalt manganese oxide is 1% by mass or more and 50% by mass or less relative to the total amount of the positive electrode active material.

主权项

1. A positive electrode for nonaqueous electrolyte secondary batteries, comprising:
a positive electrode active material composed of a mixture containing (i) lithium cobalt oxide particles having a surface to which rare-earth compound particles are partly adhered, and (ii) lithium nickel cobalt manganese oxide particles; and a binder, wherein the content of the lithium nickel cobalt manganese oxide is 1% by mass or more and 50% by mass or less relative to the total amount of the positive electrode active material, wherein the amount of the rare-earth compound particles adhered to the surface of the lithium cobalt oxide particles is 0.01% by mass or more and 0.5% by mass or less relative to the amount of the lithium oxide particles on a rare-earth element basis, wherein the rare-earth compound particles have an average particle size of 100 nm or less and 0.1 nm or more, and wherein the rare-earth compound particles are at least one selected from the group consisting of rare-earth hydroxides, rare-earth oxyhydroxides, and rare-earth carbonate compounds.