Power tool and battery pack for selective power supply to battery pack

A power tool system comprising:

• a first power tool having a first motor configured to operate at a first voltage and a first group of connection portions;
• a second power tool having a second motor configured to operate at a second voltage lower than the first voltage and a second group of connection portions of which mechanical configuration is different from the mechanical configuration of the first group of connection portions;
• and
• a battery pack configured to be connectable to the first power tool and the second power tool, the battery pack having a plurality of groups of power cells and a third group of connection portions, each group of power cells having a plurality of power cells connected in series,
• wherein the first and third groups of connection portions are configured so that, when the battery pack is connected to the first power tool, the third group of connection portions mechanically interacts with the first group of connection portions in a first form of mechanical interaction and the plurality of groups of power cells are connected in series to provide the first voltage to the first power tool, and
• wherein the second and third groups of connection portions are configured so that, when the battery pack is connected to the second power tool, the third group of connection portions mechanically interacts with the second group of connection portions in a second form of mechanical interaction different from the first form of mechanical interaction and the plurality of groups of power cells are connected in parallel to provide the second voltage to the second power tool.