BATTERY PACK

A battery pack includes a battery assembly including six batteries each having a cylindrical external shape, and electrode terminals at both end portions in a cylindrical axis direction, respectively, are arranged in a second direction perpendicular to the cylindrical axis direction in which cylindrical axes thereof are in parallel or substantially in parallel, and a tab to connect the electrode terminals of the six batteries. Assuming that three batteries arranged in the second direction are a first battery, a second battery, and a third battery in this order, the tab is connected to the first battery and the third battery without being connected to the second battery.