Thanks, good stuff!

buy a new one

I read through this thread and have a question. I'm trying to recharge a dead 2200 lipo 3cell on a onyx235. I selected nimh but it asks me to select the voltage. There is no 11.1 so which should I go with? I'm going to charge it at .5 amps. It is DEAD! It wont even light up the led readout on the voltmeter.

NiMH chargers mostly require only an amperage input.
Set it for 0.5A or less and monitor the voltage.
Do not go away and leave it!

When it reaches 10V, you can try it on the lipo charger.

If it gets warm, puffs, or does anything else, discharge and toss.

It's that my charger forces me to select a voltage even when selecting to charge nimh. I guess I'll select the closest thing to 11.1 then.

Try 10.8 .

Keep an eye on it when charging. If anything unusual starts to occur, take it outside.

I just put it on at 10.8 volts, .5 amps on the nimh setting. I let it stay on for about 15 minutes until the charge was reading over 10 volts. Took it off and plugged the voltmeter in and it lit up! It read about 3.4 volts for each cell. So then I put it to charge normally as a lipo and I'm just waiting to see how it turns out. Its charging at 2.2 amps, maybe I should have reduced that a bit.

I've been checking on it and it appears cell #2 is low. It's been at around 3.83 while the other 2 cells are at 4.25

The funny thing about this is I never overdischarged this battery. It just went dead like this. I unplugged it right after my last flight and left it overnight. The next day it was dead. Strange.

I guess if the other cell doesn't catch up I'm going to just toss it?

Edit Update: It spent 75 minutes on the charger and that cell never got up past 3.91 The others stopped at 4.25. I guess it's just done. I'm

So I pulled it and i'm gonna chuck it. Thanks for the help though.

The other option is to charge the #2 cell through the balance lead as a 1s cell.

Do you have a balancing charger? Did you balance charge it last time you charged it?
A cell can go low like that if the pack was unbalanced to begin with.

How do I do that? Yes I have a balancing charger, onyx235. No the pack has always been balanced.

See if you have a 2 pin male connector that will fit into 2 adjacent holes in the balance connector. If not, use 2 pieces of solid wire that will fit into the holes.

Add wires to the pins you have selected, red for +, black for minus and connect them to your charger.

Assuming you have a 4 pin connector, the black wire will be the starting point.
Cell#1 = Black wire is neg, #2 hole is +
Cell #2 = #2 hole is -, #3 hole is +
Cell #3 = #3 hole is -, #4 hole is +

You should check that with a voltmeter just to be sure. Be careful not to touch the voltmeter leads together or you'll short the cell.

Now push the neg pin into hole #2 and the positive into hole #3. Set the charger for 1s and 1A and charge.

But before you do all this, recheck the voltage of each cell. You said they were 4.25, 3.91, 4.25 I think. What are they today? If that middle cell has dropped more than the others it may not be worth the time to try to recover the pack.

BTW, 4.25V is too high.....4.2V is max and 4.15V is even better for long cycle life. Check those with a good voltmeter to be sure.

I just checked the battery. The first cell has dropped to 3.86 the second is 3.91 and the 3rd is down to 2.47

Not just that but I tested it a few times just to make sure and every time I attached the meter they would slightly change up or down. I think it's done. What's the best way to discharge it?

The easiest way is to hook it up to a 12V light bulb.
An auto brake light bulb or a 100W RV 12V lightbulb (same size as 120V bulbs) will do the trick.

Running it on a car or plane can damage them?

No, that would work. I would choose the car.
It will just trigger the LVC.......the problem would be with that 1 very low cell, the LVC will trigger with 2cells still having a charge in them.