| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium secondary battery having a high energy density in which battery characteristics are enhanced, and to provide a suitable method for manufacturing the lithium secondary battery.SOLUTION: There is provided a lithium secondary battery including: an electrode body having a positive electrode and a negative electrode; and an electrolyte. The positive electrode comprises a positive electrode mixture layer containing a positive electrode active material and polyvinylidene fluoride (PVdF) as a binder, on a positive electrode collector. The mass ratio (α/&bgr;) of α crystal and &bgr; crystal of the PVdF based on the nuclear magnetic resonance spectrum (NMR) is 0.42 or more and 0.56 or less. The PVdF satisfying the α/&bgr; can suppress swelling or dissolution into an electrolyte over a long period of time. Consequently, the battery performance (e.g., cycle characteristics or an output density) can be enhanced in the lithium secondary battery including the positive electrode mixture layer. |
