An interchangeable battery pack system for video game controllers is disclosed. The battery pack configured and arranged for insertion into a battery compartment of a video game controller. The battery pack has a bottom surface with a recess formed therein. The battery pack has a first set of battery electrical contacts for engagement with the electrical contacts of the video game controller and a second set of battery electrical contacts for charging the battery pack. A battery pack adapter cover is also included and is configured and arranged to releasably attach to the battery pack. The battery pack adapter cover has an aperture therethrough exposing the bottom surface of the battery pack when attached thereto. The battery pack adapter cover has mating formation thereon configured and arranged to releasably attach to a battery compartment of a video game controller for a video game system.