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Hi all – another battery question.

Just charged up my brand new Turnigy 6S 3300’s and all balanced perfectly apart from one. When this one was plugged in the charger only saw 5 cells, I went ahead and put a bit of charge in anyway and then the 6th cell appeared, but it had a low voltage (I can’t remember exactly but 2. Something).

Anyway, this cell and one other (for some reason) lagged behind the other 4 cells during charging. The charger then said the battery was charged but 2 of the cells only had around 3.6v (again I can’t remember the exact figures).

Is the battery stuffed?? No swelling or any other visual signs of distress. Maybe I give it a short run to discharge it a bit and try re-balancing??

Thanks for the help,

Graham
Yeah sure sounds like abit of a dead cell, I've been able to bring them back alittle at times but I don't think it will ever "punch" like it should, balance balance balance over and over and see how you go, your on the right track.. With the price we pay u get that sometimes I guess
As Kev said
Make sure that you are BALANCE charging and that you have the balance lead plugged in.
It might come good if you charge it a few times.
Gazz
Thanks - Yeah I have the balance plugged in and charger set to balance. I think I will run it through a charge/discharge cycle on the charger a few times and hope it comes good.

Cheers,

Graham
Charged/discharged maybe 2-3 times, the two suspect cells are now up to 3.95v fully charged.

I will try a few more times and see how it goes. If it doesn't get better than that would you risk flying with it or chuck it??

Cheers,

Graham
(12-05-2011, 08:59 AM)northerner Wrote: [ -> ]... would you risk flying with it or chuck it??

I'd suggest putting it into your plane/heli (or even better, on a bench test setup) and run it for a while, whilst keeping an eye on your wattmeter. If you can get it to tolerate being run flat-out for 4 or 5 minutes, then it's good to go in the air - otherwise, keep it for odd jobs like centering servos, programming ESCs and other ground activities.
Yeah what Steve said Smile
Yes Steve's Right sometimes you can give the battery a good load test and run all cells down low and the try re balancing.
BUT REMEMBER SAFETY WHEN RUNNING PLANES IN STATIC SITUATIONS
PROPS CAN BE DANGEROUS SO TAKE CAUTION

Steve Smile
There is the possibility that the connections from the balance lead to the cells might be a bit suss. I have seen a few forum posts where this has happened (Turnigy and Nanotech). Best way to check is to use a Digital Multimeter and measure the total voltage of the battery after charging. If it reads 25.20V on the meter then the cell is ok. 6 x 4.20 = 25.20V. If one cell is bad, it will be below 25.20V after full charge.

If you don't have a DMM, I can lend you one.
Good idea Dave - I will check that tonight.

Cheers,

Graham
Thought this a good article in how and why smart charge fyi
https://www.digikey.com.au/en/articles/t...y-charging
It's been a while since my last soldering of an xt60 connector, i understand they put xt90 on these new high discharge batteries for the current, but my EDF Stryker only draws 150 amps at full throttle, and the xt60 cope fine with the short bursts of power and For $100 id like to possibly use it on my other rc planes which all have xt60's on them.

Looking Forward to some long awaited flying this weekend if the the rain will stop, please.

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