| 摘要 |
A lithium ion secondary battery is capable of improving the energy density and power density and excellent in high rate cycle characteristics applicable to hybrid cars, etc. The lithium ion secondary battery including a positive electrode of a lithium transition metal complex oxide, a negative electrode for absorbing/releasing lithium, and a non-aqueous electrolyte containing a lithium salt, in which the negative electrode has a negative electrode active material using a non-graphitizing carbon (spacing d(002) of 0.360 nm or more by XRD) and a graphitizing carbon (spacing d(002) of 0.339 nm or more and less than 0.360 nm by XRD) surface-modified at a thickness in a range from 10 nm to 100 nm in admixture, comprising the non-graphitizing carbon and the graphitizing carbon at a ratio in the range of 90 to 50 wt % :10 to 50 wt % and, further, graphitizing carbon having a grain size larger than that of the non-graphitizing carbon is used. |
