Rechargeable battery pack

The present invention has been made in an effort to provide a rechargeable battery pack that is capable of allowing easy disassembly during repair work and waterproof performance in operation. A rechargeable battery pack according to an exemplary embodiment of the present invention includes: a cell holder for accommodating unit battery cells; a lower case for accommodating the cell holder; an upper case combined with an opening of the lower case to cover the cell holder and the unit battery cells; a tab with its end portion drawn out of a through-hole of the upper case so as to be disposed on an outer surface of the upper case while connecting the unit battery cells; and a terminal electrically connected the end portion of the tab while being overlapping therewith and combined with the upper case while covering the through-hole.