Positive electrode material for nonaqueous electrolyte secondary battery, nonaqueous electrolyte secondary battery including the same, and method for producing the same

摘要

Disclosed is a positive electrode material for nonaqueous electrolyte secondary batteries, which comprises a porous body composed of a material containing a polyanion. Also disclosed is a method for producing such a positive electrode material for nonaqueous electrolyte secondary batteries. When a carbon coating is formed on the surface of a material containing a polyanion of lithium iron phosphate or the like by a conventional method, the capacity during low rate discharge is improved but the capacity is not sufficient. In the present invention, the positive electrode material for nonaqueous electrolyte secondary batteries, which comprises a porous body composed of a material containing a polyanion, has a structure wherein the inner walls of the pores of the porous body are provided with a layered carbon, for improving the discharge capacity.

主权项

1. A positive electrode material for a nonaqueous electrolyte secondary battery comprising a porous body of a polyanion-containing material, wherein said porous body is a secondary particle formed by aggregation of primary particles, in which the primary particles are in direct contact with each other, and wherein inner walls of pores of said porous body are provided with carbon in layer state that forms continuous three-dimensional meshes, and wherein at least a part of the primary particles is not coated with carbon in a starting condition of the primary particles prior to aggregation into the secondary particle.