▎ 摘　　要

NOVELTY - An additive has an average particle diameter of 20-50 nm, a specific surface area of 750-800 m2/g, and comprises a particulate-form carbon material having ratio of oxygen to carbon in a surface functional group of 0.025-0.035. USE - Additive used in electrode for secondary battery, e.g. lithium-ion battery (all claimed). Uses include but are not limited to mobile telephone, notebook personal computer, electric vehicle, electric power electrical storage, unmanned aerial vehicle, robot, and balance vehicle. ADVANTAGE - The additive suppresses decrease in electroconductivity of secondary battery e.g. lithium-ion battery even in an extremely low temperature usage environment of less than -20 degrees C, and has excellent charge/discharge characteristics close to the room temperature, and solves charge/discharge defects even in cold regions, and has excellent dispersion, electroconductivity, rate, and cycle characteristics with very small addition amount compared with the existing electroconductive agent. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) electrode, which comprises a current collector and an active material layer formed on the current collector, and comprising the additive; (2) secondary battery, which comprises the electrode; and (3) manufacture of the additive, which involves heating the particulate-form carbon material at 400-700 degrees C, and processing the heated carbon material in aqueous acids, and drying the obtained carbon material to obtain surface-modified carbon material.