|
Matronics Email Lists Web Forum Interface to the Matronics Email Lists
|
View previous topic :: View next topic |
Author |
Message |
nuckollsr(at)cox.net Guest
|
Posted: Sun Sep 09, 2007 7:01 am Post subject: A123 Systems Nano-phosphate technology |
|
|
At 01:32 PM 9/7/2007 -0600, you wrote:
Quote: |
Whomever is designing the electronics doesn't have real experience with
A123 Systems cells. They think they are dealing with conventional Li-Ion
cells, and they are wrong.
A123 Systems nano-phosphate cells are quite different than other
Li-Ion cells. They will take a LOT of abuse. About the same amount as an
AGM. It is straightforward to make a drop-in replacement for a 12 volt
(or 24 volt) lead-acid battery using A123 Systems cells. The existing
charging system will work just fine. (It must have the voltage set
somewhere between 13.5 and 14.8 volts.)
|
Agreed, they are quite rugged compared to other devices
of this class . . . but as you've just noted one "must"
place some constraints on other features in the system
that do not already exist to support the legacy
battery technologies.
Quote: | In an airplane, you would want a warning that alerted the pilot that
the system was going over 14.8 volts and would make noise if the system
was going over 15 volts. It would also be useful to know if the battery
temperature was going over 80 Celsius. (You can go up to about 100 C
without damage, but no higher or you risk venting the cells and damaging
the plastic separator.)
|
<snip>
Quote: | If you overcharge them grossly, they will vent a small amount of
flammable vapor (like paint thinner.) If there is an ignition source,
this vapor could catch fire. The cells can also burst if overcharged
severely. That is the extent of the hazard this technology presents.
Bill Dube'
|
To be sure, these cells are one of the bright stars on
the horizon . . . but they come with a legacy of unhappy
stories, myths and concerns. There is a great deal of work
to be accomplished before the FAA is going to "feel" comfortable
with putting this product on a TC aircraft. Since the FAA's
general level of expertise is less than stellar, the task
of the competent system integrator has as much to do with
the politics of assuaging feelings as with the development
of the science and good practice.
Believe me, by the time my principal (and the Navy's battery
labs in Crane, IN) get done with these cells, far more will
be known about them than what's presently published. Further,
it's almost a given that the successful, TC'd replacement
batteries in Li-Ion technologies will not be simple
substitutes of SVLA or NiCad cells.
Bob . . .
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Back to top |
|
|
William.P.Dube(at)noaa.go Guest
|
Posted: Tue Sep 11, 2007 11:41 am Post subject: A123 Systems Nano-phosphate technology |
|
|
Quote: |
To be sure, these cells are one of the bright stars on
the horizon . . . but they come with a legacy of unhappy
stories, myths and concerns.
|
These nano-phosphate A123 Systems cells use an Iron-phosphate paste
instead of the traditional cobalt-based paste. They are an entirely
different creature becasue of this. Too bad that they are lumped in with
the "flame-thrower" style cobalt cells.
Bill Dube'
| - The Matronics AeroElectric-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|