RE: EVLN(Las Vegas zinc-air Ebus Demo, 110 mile range record) -- An Apology and Explanation

["Roger Stockton" <rstockton@delta-q.com>]

Is there any data available on how much energy it takes to "regenerate"
the spent zinc anodes compared to the energy yielded when the battery is
discharged?  That is, what is the "charge efficiency" of this battery
technology?

Certainly the technology offers impressive energy density, but if the
charge efficiency is poor then other battery technologies may make
better sense in the long run for a customer concerned with reducing
energy costs.  I suspect that the energy consumption/operating costs of
a zinc-air regeneration plant will be significantly greater than the
cost of recharging a true secondary battery.

While there is always the valid argument that an EV can be recharged
using power from renewable sources, I don't think that is justification
for adopting inefficient battery technologies when alternatives exist.

Cheers,

Roger.

> -----Original Message-----
> From: owner-ev@listproc.sjsu.edu 
> [mailto:owner-ev@listproc.sjsu.edu] On Behalf Of Dave Goldstein
> Sent: November 30, 2001 2:27 PM
> To: ev@listproc.sjsu.edu
> Cc: maltschuler@worldnet.att.net; garlow.charlie@epamail.epa.gov
> Subject: Re: EVLN(Las Vegas zinc-air Ebus Demo, 110 mile 
> range record) -- An Apology and Explanation

[snip]

>    As I recall, their Z-A battery pack puts 
> out about *six times* the Specific Energy 
> and approximately the same Specific Power 
> as a flooded lead-acid battery pack in an 
> S-10 pickup truck conversion (say 20 six 
> volt T145's) -- and weighs just about *the 
> same!* (~1425 lbs or ~650 kg.)  Pretty 
> impressive for a bus!
> 
>   The batteries also feature removable
> zinc anode cassettes that enable the 
> entire pack to be mechanically recharged
> in about 15 minutes. The spent or partially-
> spent cassettes are then recycled in a 
> regeneration plant and are returned to 
> service.
> 
>   The major issue, as with most advanced
> batteries, is *cost*.  Electric Fuel knows
> that as the cost of petroleum rises, their
> Z-A technology becomes increasingly
> competitive with diesel powered fleets.