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:
Step 1: Introduction
Making vintage retro console portables into handhelds is a very good hobby to have, you learn new skills, have to do a fair bit of problem solving in the process; and end up with something special that only a few dozen other people have in the world.
Let me show you the principles of making your own Nintendo 64 portable. With these techniques, you can progress to other console systems too as the principles therein are similar to making other systems.