▎ 摘　　要

NOVELTY - A carbon material comprises two or more reduced graphene oxide layers comprising an arylene group between the reduced graphene oxides. USE - Carbon material is used for negative electrode active material of lithium ion secondary battery (claimed). Uses include but are not limited to mobile telephone, notebook personal computer, tablet-type terminal, portable game machine, electric vehicle, hybrid car, electric motorcycle, electric-power-assisted bicycle, robot, domestic electrical storage system, etc. ADVANTAGE - The carbon material provides battery having improved initial charge/discharge efficiency and capacity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) manufacture of carbon material, which involves reacting reduced graphene oxide with an aromatic bisdiazonium salt; and (2) lithium ion secondary battery, which comprises a positive electrode comprising a positive electrode active material which is capable of storing and releasing lithium ions, a negative electrode comprising a carbon material as a negative electrode active material which is capable of storing and releasing lithium ions, and a non-aqueous electrolyte solution.