A combination is disclosed which comprises a handle module that is attachable to a detachable shaft module for collectively performing a surgical procedure, a removable, rechargeable battery pack connectable to the handle module for providing electric power to the handle module during a surgical procedure, and an intelligent charging station for charging and discharging the battery pack when the battery pack is removed from the handle module and inserted into the charging station. The battery pack comprises a memory for storing charging and discharging data for the battery pack. The intelligent charging station charges and discharges the battery pack based on the charging and discharging data stored in the memory of the battery pack.
