Somewhat related to Tesla company prospects going forward, so I'll post a link here for those interested:
A bit short on technical content, though they do provide numbers for the various Ultra Capacitor packages they produce. The guy being interviewed gives a good synopsis in the beginning concerning why Ultra Capacitor storage banks are very compatible with batteries. They provide the capability to capture the 5-10 second braking energy, and then pump it out for the following 5-10 second acceleration burst. Saving the battery the wear and tear of doing that, and prolonging battery life.
No mention of cost that I recall, so unclear whether these could/will start showing up in passenger cars anytime soon. I would imagine that if these became powerful enough, weighed less, and cost wasn't prohibitive, that some EVs would start incorporating them. Seems like it would be a good acquisition for a car company should one produce a compelling product.
The one application they mentioned that was their "killer app" was for shipyard cranes that did nothing all day but lift and drop large containers off ships. The dropping fills the capacitor, and the energy saved does the lifting. They did mention how much was saved by the company doing this, but I forget the number.
I followed the EESTOR story for a while, but they seem to have fizzled out. Also owned Maxwell Technologies (MXWL) from an acquisition angle, though their stock has languished for several years now.
RT