Why aren’t ultracapacitors used more often as range extenders in Hybrids?

Question

Seems like AFS Trinity tried it 24 years ago and nothing has been released so far that makes use of the concept.

Is there something like a combustion engine running at a sweetspot to charge ultracapacitors with a buffer battery (something like the UltraBattery concept)?

I’ve recently read about the Nissan Range-Extender concept but milage still is quite bad.

In: 1

Answer 1

A 400F supercap holds about 1/20th the energy of a single AA battery. Whilst being both heavier and larger. That probably answers your question.