Terminal of secondarey battery and method of assembling the same

A secondary battery includes an electrode assembly; a first terminal electrically connected to the electrode assembly, wherein the first terminal includes a first collecting plate contacting the electrode assembly and having at least one opening; a first terminal plate comprising at least one protrusion extending into the at least one opening; and a first coupling terminal extending through the first terminal plate and electrically coupled to the first collecting plate; a case housing the electrode assembly; and a cap assembly sealing the case.