Charger

A charger includes a battery pack receiving therein a plurality of batteries and having a projection provided with a contacting terminal, and a charger section having a mounting hole provided with a charging terminal, the battery pack being set on the charger section with the projection mounted into the mounting hole of the charger section for charging the batteries. The battery pack has vent ports through a wall on the side having the projection, while the charger section has blast ports at positions opposing the vent ports and a blower disposed to be on a side of the mounting hole and below the blast ports, for blowing air from the blower, through the vent ports into the interior of the battery pack, for elevating blow rate to the battery pack, battery cooling and gas discharge out of the battery pack.