Prius subpacks in 50V modules could run the converters for about 45-60 minutes continously. but will need BCM type monitoring and control. The ultamate battery solution for the Insight would be a light weight 144V pack of Lithium or other high power to weight batteries, with 20+ usable AH capacity.Like many things in live the good stuff cost too much.
Genesis One, LLC
If you would like to get involved or support any of these projects, please contact me at (860)935-5569.