Patent ID: 9023500
Filing Date: 2015-05-05
Classification: H01M,Y02E,Y02P

Abstract:
1. A cylindrical secondary battery, comprising: a battery unit including: a can for accommodating the battery unit; a cap assembly for sealing an opening of the can; and a first insulation plate in the can and on an upper portion of the battery unit, the first insulation plate having a circular shape and being configured to prevent a short between the first electrode tab and the second electrode plate having different polarities, wherein: the first insulation plate includes a linear small aperture through which the first electrode tab extends, one circular small aperture for injection of an electrolyte, and another circular small aperture constituting a gas discharge hole for discharging a gas, the first insulation plate is circular and corresponds to a shape of the can, the linear and circular small apertures are disposed in a region equal to or less than 50% of the first insulation plate such that the linear and circular small apertures are confined to only one hemisphere of the first insulation plate, such that all of the linear and circular small apertures are confined to only the one hemisphere of the first insulation plate, the linear small aperture extends in a direction perpendicular to a direction in which the first electrode tab is bent, the circular small apertures are disposed at sides of the linear small aperture, the linear and circular small apertures are disposed along a straight line, and a bent portion of the first electrode tab is disposed on the first insulation plate not to overlap with the circular small apertures.