I plan to use the icreate as a platform to carry a tablet, or notebook PC and want to have power for some time so I need more than the 3000 mAh battery. I want all to be powered from same battery system and use same charging source. So I need info as to how to wire in additional 14.4V NiMH batteries in parallel with the existing and how to deal with the additional temperature sensors (I could ignore of course but...). Can the built in power control deal with this? Do I need to upgrade it somehow? I would appreciate suggestions as I do not want a completely separate power system for aux devices. Charging all from standard home base is the goal even though it will take longer. I can deal with adapting the 14.4V to whatever aux devices I add. Thanks.
This project page describes many specifics of the Roomba power system. I don't think it covers adding additional batteries in parallel, but probably has lots of other helpful information for you.