Priuses use nicke metal hydride. they can be tortured, even shot and not go into thermal runaway like lithium batteries. NiMH are in my opinion better in nearly every way except energy/kg. It seems some of the articles that used to be on the web about burns fires, etc are not there. I think Nicad still has "memory issues" if left at full charge, or keep trickle charging them for months at a time you can't get the energy out unless you very carefully discharge the battery fully and then carefully recharge- even then you lose amp hours and high current capacity. There are also some environment issues with cadmium.
Kudos to the USCG and SPAWAR guys who came and stayed on the project for the digital distress system knowing it was already going to be treaty violation late when the money for the project showed up. Read Hillenbrand's Unbroken for one of the more compelling stories of what it is like to be adrift in the pacific
Arnold, you were a role model in so many ways. I think yuor contribution to having people dream of their own plane and then having that goal raised to ever more funcitonal and luxurious levels was a great motivator for many people who have employed millions of others. Thanks for never telling me what I couldn't do.