Currently I am working on a project for a portable power source that will provide 110vac, 5, 7.5, 9 and 12 volts DC. Ideally for up to 24 hours without needing a charge, but we will see how that goes. Currently I am working with some 12v 17ah and 12v 1.2ah Sealed led acid batteries similar to the ones pictured. Because the idea is to make this portable and easy to carry, I will have to balance weight and battery life. While i want as much power as possible for as long as possible, carrying 80 pounds worth of batteries is not an option. I hope to have a photogenic prototype soon, but for now, it's ugly, so you get a generic picture.