What do I need?

[Serum]

¿Lo siento?

Es la barrera de tiempo

Originally posted by Dafni
Yeah, icecream, how about Lipos?? [/B]

I am leary of lithium polymer batteries, right now. I know that if you use common sense, they are not dangerous, but sometimes I get negligent. :W:

I think that I had better stick to what I have at least a little experience with. Plus, I just got happy about the cost of motor/ESC, and I also have to figure on some upgrades. Lipo batteries are out of my price range if I want to keep all of my other RC stuff. :M:

Maybe after Christmas. ;)

If you're worried about Lithium Polymers right now, shoot a PM to MetalMan about Lithium Phosphate batts. Not sure if he's still going that route, but he'd definately know a bunch about them.

[Gustav]

Lithium who now?

Lithium Phosphate, very similar to Lipo, and even charge the same way, but aren't blow-up-able and a few other things. Like I said, I don't know much, ask MetalMan.

[coolhandcountry]

If they less blow up resistant. If they have the same properties. Like charge discharge as such. I wonder why they are not as popular. Help us out metal man.

[Batfish]

I found some information on lithium phosphate (seems to be more commonly called "Li-Ion Phosphate" or "Lithium Iron Phosphate", with an abbreviation of "LiFePO4").
It looks like there's only one company really making these batteries; Valence Technologies, Inc. ( www.valence.com ). Their Saphion batteries are cylindrical and seem like they would be the likely first candidate for R/C use, but they don't have a very high current rating as an individual cell; 11A with a 27A burst. They are 10C cells, but it looks like they are only made as 1100mah, which would mean needing to make them parallel.
Here are a couple links at Valence which are very promising.
http://www.valence.com/faq.asp?topic=phosphate
http://www.valence.com/pdffiles/IFR18650p.pdf

It looks like the batteries simply can't catch fire from abuse since the materials used to make them are non-combustible. This is even safer than nicd and nimh.

The only places I can see these cells currently in use are the Segway human transporter (scooter thingy) and a couple car companies working with them for hybrids. I can't even find them for sale on the web. Probably have to contact Valence directly to inquire.

A Google search for "lithium iron phosphate batteries" will give you a lot of articles praising the technology and some good information.

MetalMan, come and save us all! He gave me a link to a site that was selling them for rc airplanes, but that was in a PM a while ago and I think I deleted it by now.

[Batfish]

I did more searching and it looks like I was right about Valence being the only ones making these right now, and the product name is Saphion. However, I was wrong in saying noone is selling them; they're just not selling in the US.

Both e-flight and overlander in the UK are selling them.
http://www.e-flight.co.uk/shopdispla...cts.asp?id=188
http://www.overlander.co.uk/results.asp?categoryID=89

No word that I could find on when they will be in the US.

They do look promising.

[Gustav]

They seem to about half way between lipo and a gp2200 in terms
weight if you parrallel 2 together for 2400mah although the amp handling is still lower.With 3 paralled it's only slightly heavier per volt compared to gp2200 but with much higher capacity(3600 compared to 2200).Space may be a problem though.Very interesting thanks Batfish.


If you run 4 4s packs for 2400mah,25.6v that weighs 700g.But that's only 36 amps continuous,compared to 64 amps continuous for the 3200 mah Kokam 20C cells.

so still a way to go then to match lipos,i hope they do though,there metal cased which is what puts me off lipos for offroad.

[Serum]

I've seen movies of those cells, compared to lithium cells (perforated with a nail..) nice experiment.. (there was fire involved, so it's not hard to please me with those caliber of experiments..

A friend of mine, who develops electric tools told me Sony is currently producing simmular cells, only they could do 20C continues at 2200mah.. another step in the right direction if you ask me..

[coolhandcountry]

technology keeps getting better. I like that. One day you be able to get 30c 10000mah packs. that would be the schizzle.

[Serum]

I wait till the day that 200C 750mAh packs become available!!!

a 200V setup... 98% efficiency...