you don't need a separate one. 12v will work for the screen and n64. the highest capacity batteries i know about are either 6v or 12v so may as well go with that
well... lets not call it a car battery, just cuase its 12v.., now id actually not reccomend having two sets of batteries.. double the charge time, different power dissapation times..., and weight is another thing to consider... plus be realistic, just build the unit first then worry about minor things like that, run a central 12v system, trust me it will make interfacing power that much easier
something that will fit in someones pocket hopefully.... or in the case of the original idea i had.. something that will fit behind the hipgear screen..
something like this http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 54216&rd=1 should work great, there arent that many cells, and the plastic makes it look a lot bigger then it is, and its 12v the perfect voltage, and it has its own charging circuit, so you wont have to worry about cooking ur batts
actually im pretty sure you can use any 12v high amp power adapter, cause that would be all the gc adaptor is in the first place, i have a 12v 3.5 amp trans im gonna use for mine, something around 1000ma should work fine?
umm, well no real hacking needs to be done, like, just tie your volt convs and ur n64 to the battery's 12v output line, the cool part is, these batts are in cells, so you can arrange the cells in ur portable however you want, so that you can maximize space, also the charging circuit wont need to be hacked, just make sure you make a input charge port on the back of your console, so you can plug in your console
