I may be overthinking this, but I'm looking to make a Piratebox/Librarybox with an extended range (at least the size of a library) that is portable enough to fit within a large lunchbox, doesn't require much soldering or assembly (I'm wary of lead-acid batteries people like to use), and won't break the bank. Considering a desktop router would probably suck too much power, I was thinking of going the route of a Raspberry Pi with an extended-range wireless adapter. The problem I keep coming to (with probably most implementations) is the battery, as its hard for me to judge just about how much battery life I'm going to expect. I know with my TP-Link portable AP, I can expect at least 8 hours from it's built in battery piggy-backing off a cheap, $15 portable external battery, so I'm hoping anything I buy that is supposed to be a bit more robust can last at least 6-8 hours.
Still, a home router doesn't seem like a bad idea, if I can find some sort of discrete location I can plug it in. Considering we're in the portable era, there's no shortage of power outlets in any library.