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Old Oct 30, 2005, 11:59 PM
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LIPO/NIMH Comparison Sheet/Chart

Hey Guys,

I have been reading here for a while about the recent fires and near accidents with Lipo batteries. I also have read about the weight difference in a plane with Lipo's and Nimh batteries.

I have prepared a PDF file with more information regarding weight and price differences.

Is the extra 2.42oz really worth a extra $30 in batteries?
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Last edited by MichaelSTX; Oct 31, 2005 at 12:48 AM.
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Old Oct 31, 2005, 08:55 AM
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Michael,
I believe you are comparing apples and oranges - and doing it for the number of cells where the advantage is not so great. Those WallMart cells will not deliver the 20 to 25 amp current you are looking for from a 2480mahr Lipo battery. BTW, you can pick up a 2600mhar 2S Lipo (PQ-2600N-2S) for $40 (http://www.cheapbatterypacks.com/mai...6&pgid=fpacks).

Try running the comparison using a 3S lipo and 10 GP2000 cells. The GP2000s can put out 25amps without appreciable voltage drop, weigh 34.85gms (1.23oz) each and cost $4.75 when assembled in a pack w connectors (http://www.cheapbatterypacks.com/mai...id=custompack).

Then look at how much the total weight of the plane is reduced and how much you can reduce the power required to get equivalent performance. And yes, a 3.2oz weight loss may not seem like much on a purely numerical basis but it made a noticeable difference in the way a marginally-performing plane flew.

Alan
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Old Oct 31, 2005, 12:44 PM
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Well put, Al, not a good comparison.

Michael, I would suggest you try lipos - I think you will be convinced.

I was one of those guys that hesitated going to lipos. Now, I can't ever imagine buying another Nicad or NiMH.
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Old Oct 31, 2005, 05:18 PM
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What is the cost to get started with a lipo? I want atleast a half of our flying time if not more. But I'm also on a budget. I have chargers and spare batteries to use NICD or NiMH with a plane.

I'm more worried about the batteries catching fire/blowing up. Thats really the only thing I am worried about with these.
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Old Oct 31, 2005, 06:00 PM
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Quote:
Originally Posted by MichaelSTX
I want at least half an hour flying time if not more.
Whatever type of batteries you use you are going to need a BIG pack. If its a 3s Tanic 2480mAh pack ($100) you will have to average only 2C (5A) draw to get 30 minutes flying time. If you need 25A for half an hour you need a 12500mAh pack (using 3s5p of Tanic 2480's that's $500 per pack)!
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Last edited by Dr Kiwi; Oct 31, 2005 at 06:08 PM.
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Old Oct 31, 2005, 06:35 PM
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OUCH!

$500 for a pack is a little out of budget. I believe I have seen others on this forum getting those kind of times with $50 packs.

Maybe these were NiMH..

Hmmm.....

*EDIT*

I should also mention this will be used with a GWS Slow Stick.
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