| 摘要 |
The present invention relates to a cylindrical lithium ion secondary battery, capable of preventing jelly-roll-shaped electrode assembly from moving in a can in a predetermined direction when a variety of situations occurs such as vibration, falling, crushing, and collision. To achieve the purpose, disclosed is a cylindrical secondary battery, which includes: an electrode assembly wound in a jelly-roll shape, and on which a positive electrode panel, a separator, and a negative electrode panel are laminated; a can storing the electrode assembly; and a cap assembly combined with the top of the can, which is also the top of the electrode assembly. A lower surface beading part, curved towards the inside to predetermined height, is formed on a lower surface of the can, which is an area between the cap assembly and the electrode assembly. |
