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using 3c lipo to run prop starter motor

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Old 01-24-2012, 06:11 PM
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velottatv
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Default using 3c lipo to run prop starter motor

Tried using a 3 cell lipo to run a prop starter motor. It worked great but when I went to charge the lipo, it had one completely dead cell and two cells at nearly full charge. Used another 3 cell lipo to run the turnigy heater pack for the turnigy radio bag. Again, worked great but had the same results; one dead cell, two nearly full.

Any ideas why the amp draw wouldn't be equal across all three cells? Any ideas how I can bring the dead cells back to life? Thanks
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Old 01-24-2012, 06:19 PM
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Default RE: using 3c lipo to run prop starter motor

Hi, welcome to RCU. When cells are in series they must have equal current draw. I suspect your measuring device ,connection, ect. first.

Try to probe each of the 6 cells with the same voltmeter to verify
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Old 01-25-2012, 04:49 AM
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Default RE: using 3c lipo to run prop starter motor

On the same vein, are you sure you have a dead cell on both packs? Could be something as simple as a broken balance lead that's giving you a dead reading.
Easy to check, does the voltage at the main plug equal your two "good" cells? If it's higher, I'd say you have a bad balance lead.
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Old 01-25-2012, 10:43 AM
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Default RE: using 3c lipo to run prop starter motor

Good point on checking the voltage at the balance point. Both batteries showed a zero voltage cell when measure to negative. However, one battery picked up the third cell when put back on the charger and one did not. The one battery held steady and took a good charge. I'm going to dissect the bad one and inspect. Thanks for the ideas!!
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Old 04-09-2012, 02:42 PM
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Default RE: using 3c lipo to run prop starter motor

The starter motor may be a larger load than the lipo is rated for.
Initial starting current can be quite high.
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