Patent attributes
There is provided a battery pack with improved stability. The battery pack includes a plurality of bare cells including electrode units and arranged in a direction, a holder case configured to accommodate the plurality of bare cells, and a connection tab including a body unit electrically connected to the plurality of bare cells, a slit unit positioned in each of the electrode units of the plurality of bare cells, and at least one welding unit positioned to be adjacent to the slit unit and welded to the electrode unit of the bare cell. The slit unit includes first and second slits separated from each other by a certain distance, first and second bridges respectively provided between ends of the first and second slits, and a welding slit that crosses one point of each of the first and second slits. In the battery pack, one of the first and second bridges is formed to be stepped so that it is possible to rapidly and easily block flow of a current when over-charge or over-discharge occurs. Therefore, stability of the battery pack may improve.