A secondary battery includes an electrode assembly including a first electrode tab and a second electrode tab, which are exposed at opposite sides, respectively; a first collector electrically connected to the first electrode tab; a case configured to accommodate the electrode assembly and the first collector and having opposite open sides; a first cap plate configured to seal an opening of a first side of the case; and a first terminal electrically connected to the first collector and exposed to an outside of the first cap plate, and the first collector includes a first collector plate and a second collector plate, the first collector plate includes: a central portion; an edge portion extending from the central portion and coupled to the first electrode tab; and a connection portion, the connection portion including at least one bent part.