The latest issue of QST ha a interesting article.

It seems that soldiers today are carrying up to 40 pounds of batteries
for all the gear they carry.

The US Army, looking to reduce this load, is seeking a portable power
supply.

This proposed unit must provide 20W output for a minimum of 96 hours,
and weigh less than 4 kilos (about 8.8 pounds). The design contest is
open to all, and the designer who comes up with the best design wil
receive $1,000,000.

See Oct. QST for further information.

AMATEUR RADIO: A National resource!
For more information about amateur radio go to
www.arrl.org

Not to put too much of a damper on this, but I've looked into it and it's
clear that there's no trivial "off the shelf" solution that you can point to
and claim your million dollars. :-) This prize isn't going to be won by
someone tinkering in their basement -- it'll end up going to, e.g., some
researchers at a university with good connections to industry.

On Oct 23, 2:40 pm, "Joel Koltner"
wrote:
Not to put too much of a damper on this, but I've looked into it and it's
clear that there's no trivial "off the shelf" solution that you can point to
and claim your million dollars. :-) This prize isn't going to be won by
someone tinkering in their basement -- it'll end up going to, e.g., some
researchers at a university with good connections to industry.

Putting 2KWH of controlled energy into a 10# package is going to be a
real trick... Not doable with todays electrical containers - no matter
how fast that damn rabbit beats the drum...
Off the top of my head (along with flies, fleas, and dandruff) I
predict it will not be a rechargeable battery...
It will either be a version of a fuel cell with compressed hydrogen as
the fuel..
Or it will be a version of a primary battery with an erodeable anode -
for example an Fe-Cu cell with vinegar electrolyte, but likely using
lighter metals - Lithium comes to mind, of course...
When I first read this I made a mental note to look up and calculate
how many gms of copper would have to be sacrificed in an Fe-Cu cell to
generate 2KWH, but life intervened and I haven't gotten back to that
(and likely won't) so I throw it out for thinking by those with a bit
of chemistry background...

denny / k8do

Generally, I'd agree- this would seem to be a job for an
industrial/research area (I know it's beyond my [admitedly limited]
abilities) Yet, with 300,000,000 people in this country...never
underestimate what's possible.

"Never tell people how to do things. Tell them what to do and they will
surprise you with their ingenuity." Gen. George S. Patton, Jr.

AMATEUR RADIO: A National resource!
For more information about amateur radio go to
www.arrl.org