BATTERY PACK

PROBLEM TO BE SOLVED: To suppress deterioration in bond strength in a structure where an external terminal of a battery is welded with an electric connection member.SOLUTION: A battery pack includes: a plurality of batteries 30 having external terminals including a negative electrode terminal 50 and a positive electrode terminal; a bus bar 40 for connecting external terminals of adjacent two batteries 30 each other; a connecting member 70 welded to the external terminals and the bus bar 40 and electrically connecting the external terminals with the bus bar 40; a welded part 80 where the external terminals and the connecting member 70 are welded; and a welded part 82 where the bus bar 40 and the connecting member 70 are welded. The welded part 80 has a shape recessed to the outermost surface of the connecting member 70, and an apical surface 50d of the negative electrode terminal 50 is connected to a connected surface 81 of the welded part 80 without a level difference.