The present disclosure provides a secondary battery and an assembly therefor. The secondary battery comprises: a cap plate provided with a first electrode terminal and a second electrode terminal; an electrode assembly comprising a first electrode tab and a second electrode tab; a first connecting piece connected between the first electrode tab and the first electrode terminal. The first connecting piece includes a first electrode terminal connecting portion, a first electrode tab connecting portion and a first fusing portion. The secondary battery further comprises an insulating holding block, two ends of which are connected with the first electrode terminal connecting portion and the first electrode tab connecting portion respectively, and the insulating holding block is configured to maintain the first electrode terminal connecting portion and the first electrode tab connecting portion in position relative to each other when the first fusing portion is fused.