Re: Aluminum Battery?

From: Paul Nuber (nuberpaul_at_nandomail.com)
Date: 11/05/04 

Date: 5 Nov 2004 02:06:12 -0800

manofsan@yahoo.com (sanman) wrote in message news:<f144e162.0411041119.2bd480ca@posting.google.com>...
> Uncle Al <UncleAl0@hate.spam.net> wrote in message news:<41896D59.B2114BA@hate.spam.net>...
>
> > "The new, patented technology based on nanoscale electrochemistry will
> > allow production of rechargeable aluminium batteries providing up to
> > 20 times more capacity than current batteries."
> >
> > 1) Bull***, up to the "up to"
> >
> > 2) If "up to means "less than" and "not rechargeable," no problem.
> >
> > My Cable ISP gives me "up to" '100 times the speed of a 56K modem.'
> > They must have soem awsfully slow 56K modems.
>
> Hi Al,
>
> I forgot to include this link:
>
> http://www.batteriesdigest.com/id301.htm
>
> They seem to mention a little more about this, and cite some patent by
> Telcordia, formerly known as Bellcore Communications (spinoff of
> Bell/AT&T?)
>
> I surfed around looking for further links, and found
>
> http://www.arofe.army.mil/Conferences/Recent_Abstract/200th_Meeting/symposia/b1b/0203.pdf
>
> It mentions the idea of packing Al+++ into a vanadium pentoxide (V2O5)
> aerogel (ie. foamed metal oxide)
> Apparently, this "nanocrystalline" aerogel allows higher surface area
> contact with the Al+++ which means higher power output.
>

There are many problems for such system:
1. As mentioned in the above military reference, the voltage is low
(about 1 V cf Li/NiO2 4.5V). The pursue is purely academic, "we feel
that such studies
offer valuable insights ...."

2. Uncle Al also pointed out the rechargability problem. Even if you
have 99%
rechargability after 100 cycles you only get about 36% of your stuff.
I think
this system can barely recharged to 10% at the first cycle.

3. Power, kinetics, ion diffusion

Note that nanoparticle won't solve the problem, they only introduce
more mind-boggling interfaces.

best
paul