For Xbox 360 Wireless Controller AA Battery Pack Back Case Cover Holder Shell ++ | eBay
How to Make a Spare Controller Battery Pack for Xbox 360 : 9 Steps - Instructables
Amazon.com: OSTENT 2 in 1 Charger Cable + Rechargeable Battery Pack for Xbox 360 Wireless Controller Color Black : Video Games
Amazon.com: Rechargeable Battery Pack of 4800mah Replacement Battery Pack Controller Charging Package Backup Battery for Xbox 360 Charging During Games with a USB Cable and Charging Base : Video Games