| 摘要 |
PURPOSE: A lithium ion secondary battery has high capacity and long lifetime by improving the battery performance through a charging and discharging voltage control and an initial activation. CONSTITUTION: A lithium ion secondary battery comprises a positive electrode containing a positive active material represented by chemical formula 1: aLi_2MnO_3-(1-a)LiMO_2, a negative electrode, and electrolyte. In chemical formula 1, M is one or more selected from Ni, Co, and Mn, and 0<a<1. A manufacturing method of a lithium ion secondary battery comprises a step of preparing the positive active material, a conducting material, and a binder to manufacture slurry; a step of manufacturing a positive electrode by spreading the slurry onto the positive electrode current collector; a step of manufacturing a battery by injecting electrolyte and using the positive electrode; and a step of conducting an initial activation by charging one time the manufactured battery at 4.5-4.7 V. |
