| 摘要 |
PROBLEM TO BE SOLVED: To provide a negative electrode material for a lithium ion secondary battery which reaches a high density with a low pressing pressure, has a high discharge capacity, and has a superior rapid charging and rapid discharging performance and excellent cycle characteristics, a negative electrode, and the lithium ion secondary battery.SOLUTION: The negative electrode material for the lithium ion secondary battery is a mixture of a mesophase pellet graphitized object (A) with the average particle size of 10-40 μm and the average aspect ratio less than 1.3, a spherical or ellipsoidal natural graphite (B) with an average particle size of 5-35 μm, smaller than the average particle size of (A) and an average aspect ratio less than 2.0, and a graphite (C) with the average particle size of 2-25 μm, smaller than the average particle size of (A), and the average aspect ratio less than 2.0, and its mass ratio is a:b=(10-70):(90-30), (a+b):c=(60-95):(40-5). The negative electrode using the above negative electrode material and the lithium ion secondary battery using the negative electrode are provided. |
