Battery pack

A battery pack comprising:

• at least two battery cells;
• a circuit board to control charging and discharging operations of the battery cells;
• a connection tab electrically connected to the battery cells, extending towards the circuit board, and comprising a bent portion proximal to the battery cells and located within a battery area defined by the battery cells;
• and
• a cell holder accommodating the battery cells and comprising an internal surface facing the battery cells, and an external surface opposite the internal surface,
• wherein the connection tab extends over the external surface of the cell holder within a valley region of the cell holder that is defined by a recess in the external surface and has a depth in a depth direction below a peak point of the battery cells, the valley region being located between neighboring battery cells of the at least two battery cells, and the recess has a width that decreases along the depth direction toward the valley region.