I just bought the Rechargeable battery pack for xbox 360. I already had the Play and Charge Kit but it stopped working. I thought the the battery pack had died because it wouldn't charge. But when i plugged the charger into my xbox and into my controller, no light showed up. I don't know if the battery pack is already fully charged or if my charger is just screwed up.
Its probably best. It may not last very long if you don't.