Abstract: A secondary battery includes: an electrode assembly including a substrate tab including a first substrate region and a second substrate region bent to extend from the first substrate region; and a current collector plate arranged in a region corresponding to the substrate tab of the electrode assembly and including a first current collecting surface and a second current collecting surface opposite to the first current collecting surface, wherein a portion of the first substrate region of the substrate tab is in contact with the first current collecting surface of the current collector plate, the second substrate region of the substrate tab is in contact with the second current collecting surface of the current collector plate, and a welding region is located between the second substrate region of the substrate tab and the second current collecting surface of the current collector plate.