| 摘要 |
PURPOSE: To provide a lithium secondary battery excellent in charge/discharge cycle characteristics and having a high weight energy density by forming the binder of the positive electrode of the lithium secondary battery with a prescribed resin. CONSTITUTION: A butyral resin of 20 pts.wt. is added and dissolved into a mixed solvent of 100 pts.wt. of isopropyl alcohol, ethyl alcohol, and toluene to forum a binding liquid, and it is used as the binder of the positive electrode 3 of a lithium secondary battery. The butyral resin has a relatively small specific gravity of 1.1, and the volume ratio of the binder in the positive electrode 3 can be increased when it is mixed with an active material at the same weight ratio. The binding force with the active material is increased, and the discharge cycle characteristic is improved. Since the butyral resin is soluble in the solvent, it can be added in the fused state, the dispersibility is improved, the quantity of the binder is reduced, and the weight energy density can be increased. |
