| 摘要 |
The invention relates to a cylinder type lithium ion secondary battery having a center pin that is inserted into an electrode assembly after the injection of electrolyte to increase impregnation of the electrolyte. The battery includes an electrode assembly, a case to accommodate the electrode assembly, a center pin inserted into the center of the electrode assembly, a cap assembly to seal an upper end opening of the electrode assembly, and an upper insulating plate disposed between the electrode assembly and the cap assembly. The upper insulating plate has a hollow formed in the center through which the center pin can penetrate, and the hollow has a center pin separation preventing unit bendable only toward the electrode assembly when the center pin penetrates through the hollow. |
