Battery pack

A battery pack configured by arranging a plurality of unit cells in a predetermined direction, the battery pack comprising:

• a plurality of unit cells each including an electrode body having a positive electrode and a negative electrode, a battery case accommodating the electrode body, and external terminals attached to the outside of the battery case, wherein
• in the plurality of unit cells, one external terminal and another external terminal are linked to each other by a bus bar between the adjacent unit cells;
• the bus bar is a plate-shaped member extending in the arrangement direction and has two terminal connection portions which overlap the respective external terminals, and a linking portion for linking the two terminal connection portions;
• a linear welded portion is formed in a portion where the terminal connection portion of the bus bar and the external terminal overlap with each other;
• the linear welded portion is non-annular in a plane of the terminal connection portion, and has
• a straight linear portion that extends in a direction orthogonal to the arrangement direction, and
• two circular arc portions that extend from respective ends of the straight linear portion and are curved toward a side opposite to the side where the linking portion is located.