Problem with hybrid-electrics is what do you do with the batteries at the end of vehicle life?
Pb-Acid, Li-Ion, NiCad all are considered hazardous. Moreover, while hybrids have great urban short trip performance, their long haul and unimproved surface performance is substandard.
Wait ten years for some gen IV nuke plants to come online, hydrogen infrastructure to build, and civil fuel cells to mature. Then go out and buy an H2 fueled Wankel - SOFC hybrid.
It troubles me to continue to see ignorance stated as fact. Most 'hybrid' cars, including the Toyota Prius, use a Ni-Mh battery pack. This technology can be (and is required by law to be) recycled with remarkable efficiency and very little waste. After all of these years, failures of the Prius battery pack are still under the one percent mark, and the prices for replacement packs (yes, that day will come for some) continue to drop.
A friend with an old Prius gets 48 MPG with mostly highway driving, while another friend with a new Prius gets 53 MPG in mostly city driving. While these numbers fall short of the EPA sticker, the fact that this car tops the Consumer Reports list in the "Customer satisfaction" category.
We are all skeptics, but the numbers don't lie. The 'hybrid' should be viewed as a "stop gap" technology, but its life as such will likely be extended by this hydrogen-highway sham. Nuclear power using 21st century technologies coupled with cars like the EV1 and the RAV4EV would be a much better solution, but there is little interest amongst those who matter (the oil industry and our elected representatives that are beholden to them).
Recycle them. As I recall, the recycle rate of lead batteries is around 90+% (or higher---its been a while since I looked up the statistics)---[late note--one source on Google gives the rate as 97.1% between 1997 and 2001]. I suspect the way it will work is you will drive back to the Toyota dealer (for your Prius), they will pull the old batteries and send them to the recycler, and put new ones in.