|
|
The cost scales with A-hrs. These will be pricey little fellows, at
least for the first year or so.
Each cell can produce about 120 cranking amps and 2.3 A-hrs. It
takes 4 cells to make 14 volts. Each set of 4 cells will weigh 0.62
lbs, plus the electronics and the case. I'm figuring that the typical
battery will have a total of 20 cells. This will offer 600 cranking
amps,11.5 A-hrs, and will weigh about 3 1/2 lbs with the case and
electronics. It would not be difficult to make batteries with more (or
less) amp-hrs and more cranking amps. We would just put more (or fewer)
cells inside. The size, weight, and cost would scale with the A-hrs
(and cranking amps). A 480 cranking amp battery would have 9.2 A-hrs,
and would weigh just under 3 lbs.
The tough part to swallow will be the cost. It looks like the
20-cell batteries will sell for about $900. As the price of the cells
goes down, the cost of the batteries will also go down. These are the
only Li-Ion cells that are safe for aircraft use, so you have to pay
the price for that. It is nothing I have control over.
I'll likely make smaller and larger batteries, depending on what
folks want. Again, it will be Winter before they go on sale. There is a
lot of work that must be done beforehand. I plan to run one in my car
for a few months for thorough testing before I put one in an airplane.
I should note that these batteries will have an open circuit
voltage of 13.6 volts. This is the minimum voltage you should set your
voltage regulator. The maximum voltage is 14.4 volts. 13.8 to 14.2
volts is pretty typical, so most regulators would not have to be
adjusted.
Lead-acid has an open-circuit voltage of about 12.9 volts when
fully charged (less when discharged.) Thus, these Li-Ion batteries at
13.6 volts will have an easier time starting your engine.
Bill Dube'
Tracy Crook wrote:
Yep, hard to beat old dinosaur juice for energy density. But
put me down for a "Yes" on wanting one of those A/C batteries. The
starting current is fine but I'd like to keep about 20 amp-hours on
board for alternator failure situations. What is the AH range you
anticipate doing?
Tracy
-----
Original Message -----
Sent:
Thursday, July 06, 2006 1:23 AM
Subject:
[FlyRotary] Re: Nothing to do with Rotary Engines, but....
At the moment, about the best that commercial Li-Ion rechargeable
cells can do is about 200+ W-hr/kg.
In more familiar units, this translates to about 1/2 HP for an hour
for each pound of batteries carried. Basically, the weight in pounds
will be twice the HP times the number of hours that you want.
Good for a motor-glider, but that is about it.
Bill Dube'
At 07:45 PM 7/5/2006, you wrote:
>Really was something to see that Bike burn out...
>
>Or may even to skew Bob's comment some, How about 175hp for 20
minutes, then
>125hp for 4 hours, with a 30 minute 175hp reserve.
>
>Tony Snow (Bearhawk #753)
>
>-----Original Message-----
>From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]On
>Behalf Of Bob White
>Sent: Wednesday, July 05, 2006 9:01 PM
>To: Rotary motors in aircraft
>Subject: [FlyRotary] Re: Nothing to do with Rotary Engines, but....
>
>
>Very impressive indeed. Another one or two orders of magnitude
>improvement and we can forget the rotary and just put an electric
motor
>up front (or out back if you're so inclined). Now that would be
>simple, reliable, and quiet too boot. How about it Bill? Can you
give
>me 175 HP for 4-5 hours in 200 lbs or so? (Damn the cost, that
would
>be worth taking out a new mortgage on the house.) ;)
>
>Bob W.
>
>
>On Wed, 5 Jul 2006 20:36:29 -0400
>"Ed Anderson" <eanderson@carolina.rr.com>
wrote:
>
><snip>
> >
> > Very impressed with your electric drag bike endeavors - got
to be almost
>as
> > good as flying a rotary {:>)
> >
> > Ed
> >
> > Ed Anderson
> > Rv-6A N494BW Rotary Powered
> > Matthews, NC
> > eanderson@carolina.rr.com
> > http://members.cox.net/rogersda/rotary/configs.htm#N494BW
> > ----- Original Message -----
> > From: "Bill Dube" <William.P.Dube@noaa.gov>
> > To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> > Sent: Wednesday, July 05, 2006 7:50 PM
> > Subject: [FlyRotary] Nothing to do with Rotary Engines,
but....
> >
> >
> > > This has absolutely nothing to do with rotary engines,
but I thought I'd
> > > show you what has been distracting me from my airplane
construction as
>of
> > > late.
> > >
> > > For those of you that don't already know, my other hobby
is drag racing
>an
> > > electric motorcycle. (It takes a team of people to do
this, not just
>me.)
> > > We recently managed to get sponsorship from A123
Systems. These
>batteries
> > > are like "Mr. Fusion" in the movie "Back to the Future."
Enormous power
> > > and a bottomless pit of energy. The more I work with
these batteries,
>the
> > > more impressed I become.
> > >
> > > Here is a clip of the bike doing a burn-out:
> > >
> > > http://www.killacycle.com/Burnout.wmv
> > >
> > > Here is a clip of the bike turning parts of the rear
motor into
>molten
> > > copper as it goes down the strip:
> > >
> > > http://www.killacyclecom/Second%20Run.wmv
> > >
> > > We can do six burn-outs and six runs without
recharging if we cared
> > > to. Maybe seven.
> > >
> > > The 170 battery pack puts out over 350 HP. The
battery pack is 376
> > > volts, 1350 amps, and has 18.4 A-hrs. We charge up in
about 15 minutes
> > > after every run.
> > >
> > > I plan to start building airplane batteries with them
soon, by the
>way.
> > > It will be late Winter, probably. A123 Systems batteries
are ideal for
> > > aircraft. They are lightweight, powerful, robust, long
cycle life, and
> > > very, very safe. I'm pretty sure I can build a battery
that will crank
>500
> > > amps, but will weigh less than 3 lbs.
> > >
> > > I guess it had something to do with airplanes.... :-)
> > >
> > > Bill Dube'
> > >
> > > --
> > > Homepage: http://www.flyrotary.com/
> > > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
> > >
> >
> >
> >
> > --
> > Homepage: http://www.flyrotary.com/
> > Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
>
>
>--
>http://www.bob-white.com
>N93BD - Rotary Powered BD-4 (first engine start 1/7/06)
>Custom Cables for your rotary installation -
>http://www.roblinphoto.com/shop/
>
>--
>Homepage: http://www.flyrotary.com/
>Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
>
>
>
>--
>Homepage: http://www.flyrotary.com/
>Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
--
Homepage: http://www.flyrotary.com/
Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/
|
|