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Number of Cells in Li-Po battery

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Old 09-02-2006, 07:22 PM
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spud4030
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Default Number of Cells in Li-Po battery

I'm a newbie to electric helicopters. I'm going to upgrade my 36 with brushless motor, ESC, and Li-Po battery.

I understand the mA ratings of batteries, but what's the significance of "number of cells"?

Also, what's the difference between the 11.1 vs. 7.4 volt batteries?


Thanks
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Old 09-02-2006, 07:53 PM
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SeaComms
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Default RE: Number of Cells in Li-Po battery

Hi Spud,

The LiPO batteries are 3.7 volts per cell, so a 2 cell battery is 7.4v and a 3 cell is 11.1v (same way as NiCads are 1.2v per cell and it requires 8 cells for a 9.6v pack). Next is the amperage and then the "C" rating, which is the maximum sustainable discharge rating.

So therefor, a 1500mAh with a 10C rating (any voltage or number of cells) will give a maximum of 15 amps continuous discharge.

The general concensus is for a minimum of 20 amps, so 12C and around 1700mAh is perfect. A larger mA battery will give you longer flying times and a larger "C" rated will run much cooler, but both are heavier so its a trade off between weight and capacity. A 2200mA 10C battery is also not bad, but as just mentioned, usually up around the 180 grams mark compared to the 1700 mA being around the 130 gram mark.

Cheers, Dave.
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Old 09-02-2006, 09:09 PM
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Default RE: Number of Cells in Li-Po battery

Seacomms
Super, thanks for the explaination.
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