|
|
Aside from price, there really is no downside to this technology. You have to have some electronics to monitor the cells and to trim them into balance, but that is all you must add.
Unlike other Li-Ion cells, you can't set these on fire, not matter what you do, (aside from putting them on the barbecue.) These cells are rated to go up to 100 C. I personally have taken them way over that temperature (short term) without any noticeable effects. I have tried to blow these cells up on the bench and I haven't been able to. It is possible to get them to vent if you REALLY abuse them, but that is about it.
They are rated at 2000 cycles. They lose about 5% capacity for every 1000 cycles. If you are willing to live with 50% capacity, they will last about 10,000 cycles.
Overcharging them and/or running them completely flat will greatly reduce their cycle life, but will not make them blow up or do anything nasty (unlike other Li-Ion cells.)
Like I said, these are like "Mr Fusion" on "Back to the Future."
Bill Dube'
Ed Anderson wrote:
Bill, I Certainly would be interested in a 3 lb 500 amp crank - depending on price. I started out with 44 lbs of batteries in my aircraft back in 1998 and am now down to 14.5 lbs. I am told that you can get 3 fpm more rate of climb for each 1 lbs less weight, so that could give me 11.5*3 = 34.5 fpm increase. Of course, I could go on a diet and get twice that for no cost {:>)
Very impressive battery technology - so what are possible down sides (other than perhaps price)?
In fact, with that kind of battery power, an electric motor "supercharger" producing 1 - 3 psi of boost just might be possible (for a short duration - say enough to give you an additional 15 HP on take off for 3 minutes.
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.killacycle.com/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/
|
|