A rechargeable battery pack including: a cell holder configured to accommodate unit battery cells; a lower case configured to accommodate the cell holder; an upper case attached to an opening of the lower case and covering the cell holder and the unit battery cells; a tab having an end portion drawn out of a through-hole of the upper case to be on an outer surface of the upper case while coupling the unit battery cells; and a terminal electrically coupled to the end portion of the tab while overlapping therewith and attached to the upper case while covering the through-hole.