Hi guys, I've decided to build myself a solar powered power pack so that I can charge my iPad when I'm traveling, but I'm missing the knowhow. Obviously that's why I'm here So this is my inventory so far: 1. 20W Solar Panel Output: 24V/900mA 2. Car cigarette charger adapter for iPad (CAR-C29): Input: 12-24V DC Output: 5.1V DC / 2.1A 3. I need help choosing the right battery pack (LiPo?) and (4.) effective charge controller combination. And since this is a portable pack I need to minimize the bulkiness of the whole thing, so I'm ready rip plastic boxes and melt solder if needed! Thanks!