This system runs off Li-ion batteries which are powerful enough to run the system, and are also rechargeable cells.
With this series of comprehensive videos, you can. The video series has attracted a considerable internet interest to date on the major gaming sites and YouTube, so I thought i'd post this guide onto Instructables too.
If you're looking at making such a system, or another portable for that matter, please join my active forum, where we can hand-hold you through the process and offer help and assistance as and when you need it; it is a very friendly and helpful community:
Here is a video of the final system: