Carbonaceous coated graphite particles for lithium ion secondary battery anode material, lithium ion secondary battery anode and lithium ion secondary battery

摘要

Provided is a negative-electrode material with which it is possible to obtain exceptional cell properties when said material is used as the negative-electrode material of a lithium-ion secondary cell.Carbonaceous coated graphite particles for the negative-electrode material of a lithium-ion secondary cell in which a carbonaceous material is provided on at least part of the surfaces of graphite particles that are obtained by anisotropically applying pressure to spheroidal and/or ellipsoidal graphite, wherein the carbonaceous coated graphite particles satisfy conditions (1) through (3) below. (1) The carbonaceous material content is 0.1-3.0 parts by mass per 100 parts by mass of the anisotropically pressurized graphite particles in the carbonaceous coated graphite particles. (2) The pore volume of pores measuring 1.1 [mu]m or less in diameter is 0.100 mL/g or less as measured by a mercury porosimeter, and the ratio of the pore volume of pores measuring 0.54 [mu]m or less in diameter with respect to said pore volume is 80% or greater. (3) The dibutyl phthalate (DBP) oil absorption is 40.0 mL/100 g or less.