NOVELTY - A negative electrode (10) has a core material (11) and a negative electrode active material layer (12) formed on surface of core material. Negative electrode active material layer contains primary carbon particles (13), secondary carbon particles (14), and binder (15). The primary carbon particles have artificial graphite particles and amorphous carbon layer formed on surface of artificial graphite particles. The median diameter (D50) of the primary carbon particles is 5-25 mu m. The median diameter (D50) of the secondary carbon particles is 0.2-10 mu m.    USE - Negative electrode is used for lithium ion secondary battery (claimed) used as power supply for hybrid car, electric vehicles, and portable electronic device e.g. mobile telephone and notebook-type personal computer.    ADVANTAGE - The lithium ion secondary battery using the negative electrode has high capacity, cycling characteristics, and input-output characteristics at the time of charging/discharging by high current density.    DETAILED DESCRIPTION - A negative electrode has a core material and a negative electrode active material layer formed on the surface of the core material. The negative electrode active material layer contains primary carbon particles, secondary carbon particles, and a binder. The primary carbon particles have artificial graphite particles and amorphous carbon layer formed on the surface of artificial graphite particles. The median diameter (D50) of the primary carbon particles is 5-25 mu m. The median diameter (D50) of the secondary carbon particles is 0.2-10 mu m. The median diameter of primary carbon particles is greater than the median diameter of secondary carbon particles. The content of secondary carbon particles in the negative electrode active material layer is 1-10 parts mass with respect to 100 parts mass of primary carbon particles. An INDEPENDENT CLAIM is included for lithium ion secondary battery, which has a positive electrode, a negative electrode and a separator interposed between the negative electrode and positive electrode.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of negative electrode. (Drawing includes non-English language text)    Negative electrode (10)    Core material (11)    Negative electrode active material layer (12)    Primary carbon particles (13)    Secondary carbon particles (14)    Binder (15)