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mat3833
11-17-2005, 06:19 PM
http://www.rcgroups.com/forums/showthread.php?t=403527
http://power-motion.com/
http://www.ultimaterc.com/forums/showthread.php?p=481558
the only links i have. they have a .2 v higher voltage per cell than lipos now. they have a metal case and weigh slightly more than lipos (the case is why) they are more stable and more durable than current lipos. one 9.6 v pack will cost between 36 and 99 dollars. a 36 amp continuous and 56 amp peak pack will cost 67.99. the 99.00 dollar one can do 54 amp constant and 84 amp peak. and the 36.00 one can do 18 amp continuous and 28 peak. these look realy great but i dont have much info on them. ask questions and i will try to find the answer. oh and their name is LiFePO4 (Lithium Iron Phosphate) cells.

Matt

pimpsmurf
11-17-2005, 06:31 PM
Not to mention a 2-3C charge rate! woot woot!

They do *NOT* have .2v higher than lithium polymer. They are 3.2v each, which is .4-5v lower than lithium polymer. They have .2v higher than non-rechargable lithium cells, and they are heavier, and the diminsions are not yet known and a $240 dedicated LiFePO4 charger is kind of expensive. :eek:

Definately might be an extremely expensive alternative to lithium ion cells, but probably not lithium polymer.

*EDIT* Oh crap. might be chargable with a regular old lithium ion/poly charger! *EDIT*

*RE-EDIT* hot damned. the mamba controler is actually capable of 4 lithium polymer cells, although the motors will probably get eaten alive at that voltage. Maybe the Aon or Hyperion will be able to handle a 4s2p setup of these (although I'm not sure that the battery holders will accomodate them. I believe the cells may be about 18mm around, and 65mm long. I'll measure the chassis later.

If we could fit a 4s2p setup of these, that would give us 12.8v@2.4ah!!! talk about runtime, provided your motor doesn't eat itself! It would be INSANELY HEAVY however! Stupid heavy. like 11-12oz heavy. OUCH!

Fortunately, you could use a 4s1p configuration and still get that 12.8v, but only 18a constant discharge (28A 30 second burst). I wonder if that is enough current for a hyperion on a mamba 25... probably not, but slightly lighter than 8 gp1100 cells... Reminds me of a song lyric... "Oooo, and it makes me wonder..."

-JNY

Hawk
11-17-2005, 07:09 PM
One of the posts said the manual lithium chargers could be used if you can set the charge voltage because it is different. I listed the max charge voltage per cell.
I have been looking for a really good lithium charger and this one looks like it.
On another note, this technology may be the answer to the problems of running brushless 1/8 scale. The high C discharge ratings help get away from the high voltage need with lipo packs to drive the BIG motors. Looks really interesting.
:cool:

pimpsmurf
11-17-2005, 07:21 PM
Actually, you can charge it to 4.2v/cell because a smart charger will switch from CC->CV and the cell will only pull 3-4ma, which makes it safe for 4.2v charging. You can unplug it after it hits 3.35v or so and you are fully charged and ready to rock and roll. The 2-3C charging is what gets me pumped up. They said 4c charging will hurt the cell in the long run, but won't cause a fire or anything if the cell isn't damaged before putting it on the charger. But 3C charging means 35-45 minute charging! My lipo charger has a max 3A I think though. :( I couldn't fast charge a 2.4AH pack. :(

*EDIT* responce from simon@amberjac-projects.co.uk:
The cells are 18mm diameter, 65mm long and each weighs 40gms.

I might be able to fit 2-4 of those on my MZM, which would be INSANE runtimes...

sweet...

-JNY

Hawk
11-17-2005, 09:16 PM
I found a place that carries the schulze Chameleon isl 6 330d charger for $219 + ship.
I read a review on these things. They are the real shiznitz.
This is their entry level charger, top o the line is $900 +.
http://www.bvmjets.com/Accessories/schulze.htm
I may get one cause I can manage my motorcycle battery while charging my lipos. :cool: