I am getting into what I am reading about these things!:
http://www.solarpanelsplus.com/solar-battery/
Here is the spec sheet on the smaller battery:
http://www.solarpanelsplus.com/solar-battery/S30-0080TechInfoSheet.pdf
These might be better suited for a basement or garage where weight and space is not as big an issue as it might be in a portable unit.