Patent ID: 8378624

Claim:
A battery charger comprising: a housing including a plurality of charging ports, each of the plurality of charging ports configured to receive a battery pack; a power supply module electrically connected to a power source and configured to supply power to the battery charger, wherein the battery charger operates in a normal operational power mode and a low operational power mode; a controller configured to determine whether one or more of the plurality of charging ports is to receive a first charging current, determine whether one or more of the plurality of charging ports is to receive a second charging current, wherein the first charging current is greater than the second charging current, and operate the battery charger in the normal operational power mode when one or more of the plurality of charging ports is to receive the first charging current or the second charging current; at least one protection circuit including at least one semiconductor switch, the at least one semiconductor switch configured to prevent a charging current from being supplied to a charging port when a defect condition related to the charging port is detected; and a battery pack detection device positioned within at least one of the plurality of charging ports and electrically connected to the controller, the battery pack detection device configured to provide an indication to the controller of a presence of the battery pack in the at least one of the plurality of charging ports, wherein the battery pack detection device provides an electrical connection between the at least one of the plurality of charging ports and the battery pack.