Lithium cell tests

[typhoon_driver]

Lithium cell tests

John, I would be interested to hear if you have had anymore experience with these cells. I have since discovered that the nicads i have will not be powerful enough for my new featherweight (they got very hot, very quickly!) and I need something light but with a large capacity and hence these seem ideal.

[david_b]

Lithium cell tests

Now I know why fans could be a nice idea in a lightweight. Would PC fans work in feathers? Like, large fans?

[kodster]

Lithium cell tests

David, I think so, but they would make one heck of a noise, like in my home computer, even the new ones.

(Message edited by kodster on May 15, 2007)

[typhoon_driver]

Lithium cell tests

I am planning on fitting some 60mm fans to keep the nicads cool but even still they heat up to ouch this is a bit hot to hold temperature in around 30 seconds.

Not too surprising when I am running a 3hp mag off them

[typhoon_driver]

Lithium cell tests

Been browsing the net and come across the Xtrema charger from TME.

http://www.tmenet.com/http://www.tmenet.com/

Apparently it will handle 10 lithium cells and is usable with A123 cells. Looks like quite a nice charger.

[woody]

Lithium cell tests



(Message edited by woody on May 16, 2007)

[terrorhurtz]

Lithium cell tests

Yup, the Xtrema looks good.
The Astroflight 109 Lithium charger also apparently now handles A123 M1 cells. It costs $120. Around £90 in UK model shops.

[terrorhurtz]

Lithium cell tests

What NiCads are you using Gary? We just did another test with the Lithiums, running THz round on a nice grippy tarmac carpark for four mins, doing a fair bit of heavy pushing. Pulling up to 150 amps (briefly). And we accidentally only had three out of the four Lithium packs connected. They were only warm at the end.

With the A123 Lithiums, you will dramatically shorten their life if they get over 60 degrees C.

You should connect a 100 amp shunt (or a whattmeter - http://www.westlondonmodels.com/product1836/Astro-Super-Whattmeter/http://www.westlondonmodels.com/prod...er-Whattmeter/ or http://www.alshobbies.com/shop/lookupstock.php?pc=4870http://www.alshobbies.com/shop/lookupstock.php?pc=4870) to your battery pack to see what sort of currents you are drawing.

[leorcc]

Lithium cell tests

Just for my frame of mind, are the A123 cells under FRA rules now allowed in heavies or not?

Because for now it stated ALL lithium based batteries are allowed up to featherweights only.

[terrorhurtz]

Lithium cell tests

From experiences they have had with the Victor speed controller in the states, it would seem that it is quite hard to get a fan to survive inside a robot. And those are only 40 mm fans.

[terrorhurtz]

Lithium cell tests

No, Lithiums batteries of any type are not currently cleared for use in heavyweights.

We have been chosen as one of the teams to evaluate them for use in heavies.

[terrorhurtz]

Lithium cell tests

Gary - note the Astro whattmeter only handles up to 70 Amps, which may not be enough for your needs. Pity those poor NiCads....

(Message edited by terrorhurtz on May 16, 2007)

[typhoon_driver]

Lithium cell tests

the nicads that i have currently have are the Sanyo RC 2400 12v Sub C NiCads sold on overlander. Not too surprising that they are having a hard time off a 3hp mag. I am looking at running the mag off the nicads and get around 6 spin ups and the drive off some nimh i have lying around.

I wish I had the cash to invest in lithium batteries but sadly its not available at the mo. I will just have to win a few events through the summer

[stu]

Lithium cell tests

Gary you must be doing something iffy then coz Vortex used the same batteries to great success and they were fine. And also i beleive Dizzy Tilly is running 3700mah NiMhs which dont give out as much current as the RC2400 Nicad Cells but is still using them fine and lasting fights and come out only a bit too warm but there fine.

Mr Stu

[blazerbotics]

Lithium cell tests

Alpha has blew both the Sanyo 2400nicads and GP3700 NiMhs, the 3000nicads (Botpacks) although can handle it but weigh too much so i can only run at 12v (not 14.4v) for comps. Im looking into these lithium cells but as i only run 14.4v (or maybe 13.2 or 16.5 for these) maybe its worth me taking a different route rather then using a modded Dewalt 36v pack.