BATTERY PACK INCLUDING A CIRCUIT INTERRUPTER

A battery pack for use with a surgical instrument is disclosed. The battery pack comprises a battery housing, batteries positioned in the battery housing, and an interruption member. The battery housing includes electrical contacts configured to electrically couple the battery pack to the surgical instrument when the battery pack is attached to the surgical instrument. The interruption member is movable from a first position where the interruption member electrically disconnects at least one battery from another battery and a second position. The batteries are electrically connected to the surgical instrument when the interruption member is moved from the first position to the second position and the battery pack is attached to the surgical instrument.