A secondary battery structure includes a jar body, a conductive stacked structure, and two end covers. The conductive stacked structure is configured in the jar body and at least includes a battery unit. The two end covers are respectively fixed at two ends of the jar body. The end covers are assembled to the jar body by inward compression in order to eliminate dimension errors of the conductive stacked structure in the jar body. The diameter of each end cover is smaller than or substantially equal to the inner diameter of the jar body.