Of course, you can have kinetic energy recovery systems with combustion engines, too. There were hydraulic systems, there are flywheel systems, and there are compressed air systems in development. You can have heat energy recovery systems, too, so the total efficiency of the combustion driven vehicle might definitely increase ...

Regarding electrochemical batteries, for high specific energies, you need high free energy (high voltage, high charge storage capacity) and low weight. And as you need electric conductors, you can't get much better than lithium (if you don't have metallic hydrogen) regarding charge and weight. And even the 2.91 V of a lithium-air battery can really be called bad.
So you might come up with five times higher specific energy and energy density than with today's cells. That will still be an order of magnitude less than for petroleum-derived fuels.

-- Michael

-----Original-Nachricht-----
Betreff: Re: [TML] Re: Understanding batteries and solar and motors.
Datum: Thu, 08 Oct 2015 08:16:51 +0200
Von: xxxxxx@shadowgard.com
An: xxxxxx@simplelists.com

On 7 Oct 2015 at 14:40, Knapp wrote:

Another factor is that most electric vehicles have regenerative
braking.

That's one of the *big* advantages of an electric over internal &
external combustion engines.

Oh yeah, not only will batteries get better with TL, motors will too.
Lighter, more powerful, etc.

But currently, batteries are the big limit.

Another problem is that as batteries sapproach (or pass) the energy
density of gasoline