Power device coupling a plurality of cells

A power device comprising:

• a plurality of cells, each having an end;
• a battery module for coupling the plurality of cells rectilinearly and fixing a connecting terminal to the end of at least one of the plurality of cells;
• a bus bar connected to the connecting terminal of the battery module, and a setscrew penetrating through the bus bar, wherein the connecting terminal includes:
• a fixing plate portion welded and fixed to the end of the at least one of the plurality of cells;
• an outer cylindrical portion protruding in an axial direction of the end of the at least one of the plurality of cells from the fixing plate portion, the outer cylindrical portion having a tip surface, and the outer cylindrical portion being substantially cylindrical in shape;
• an end face plate portion closing the tip surface of the outer Cylindrical portion;
• and
• an inner cylindrical portion provided in a central part of the end face plate portion, positioned on an inside of the outer cylindrical portion and protruding from the end face plate portion toward the fixing plate portion, the inner cylindrical portion having an internal surface and a female screw on the internal surface, and the inner cylindrical portion being provided concentrically with the outer cylindrical portion,
• wherein the setscrew engages the female screw such that the bus bar is fixed to the connecting terminal,
• wherein the connecting terminal is made off a metal plate integrally forming the inner cylindrical portion and the outer cylindrical portion, and
• wherein a length of the female screw on the internal surface of the inner cylindrical portion is equal to or greater than three times the thickness of the metal plate.