The present invention relates to a secondary battery structure. The secondary battery structure includes: a can; an electrode assembly accommodated in the can, the electrode assembly including a cathode tab and an anode tab; a cap plate sealing an opened upper end of the can; and an upper insulator disposed between the can and the cap plate, the upper insulator having a cathode tab hole for the cathode tab, an anode tab hole for the anode tab, and an injection/impregnation hole for injecting and impregnating, wherein each of the cathode tab hole, the anode tab hole, and the injection/impregnation hole extends in a length or width direction of the upper insulator and is symmetrical with respect to at least one of a line (a) that equally divides the upper insulator in a width direction and a line (b) that equally divides the upper insulator in a length direction.