The present disclosure provides a secondary battery which comprises a cap plate, an electrode assembly and a first protecting piece. The cap plate comprises a first electrode terminal. The electrode assembly comprises a main body and a first electrode tab. The first electrode tab is electrically connected with the first electrode terminal. The first electrode tab includes a first connecting portion and a first bending portion, the first connecting portion is electrically connected with the first electrode terminal, and the first bending portion connects the main body and the first connecting portion. The first protecting piece is fixed to a bottom of the first connecting portion. The first protecting piece includes a main portion and a first curve portion, the first curve portion is connected with the main portion and is curved relative to the main portion. The first bending portion is bent downwardly along the first curve portion.