Power supply device, vehicle using the same, bus bar, and battery cell electrical connection method using the bus bar

摘要

In order to ensure the strength of the connection while maintaining the miniaturization of the bus bar, a battery cell laminate in which a plurality of battery cells having positive and negative electrode terminals on one surface are stacked, and electrode terminals of adjacent battery cells A power supply device comprising a plurality of bus bars (40) that connect each other, wherein each bus bar (40) is at least partially thin-walled region (61) that is partially thinner than other regions. And an opening window (62) that is partially opened is formed in the thin region (61), and the thin region (61) is formed in an elliptical shape that is long in the stacking direction of the battery cells. The opening window (62) is extended in a direction along the long side of the elliptical shape. With the above configuration, the upper and lower thin regions (61) on the long side of the thin thin region (61) can be secured as a joining region for laser welding, and the bonding strength between the bus bar (40) and the electrode terminal. Can be secured.