Jfe Steel Corporation

Jfe Chemical Corporation

Yasushi Madokoro

Akira Matsuzaki

Yusuke Fushiwaki

Mikito Suto

Ryota Yamaji

Provided is spherically-shaped coated graphite exhibiting excellent cycle capacity-maintaining property when used as a negative electrode material for a lithium ion secondary battery. The spherically-shaped coated graphite includes: spherically-shaped graphite in which primary particles with an equivalent spherical diameter of not more than 0.8 &#x3bc;m have a volume ratio of more than 40.0% and not more than 70.0%, and primary particles with an equivalent spherical diameter of not less than 1.5 &#x3bc;m and not more than 3.0 &#x3bc;m have a volume ratio of not less than 3.0% and not more than 17.0%, in a particle size distribution of primary particles obtained using X-ray computed tomography; and a carbonaceous substance covering the spherically-shaped graphite, and a pore volume of pores with a pore size of 7.8 nm to 36.0 nm is not more than 0.017 cm/g, and a mass of infiltrated dibutyl phthalate is less than 0.70 g/cm.

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Tokyo, Japan

Yasushi Madokoro