Lipo at 2.6V?

I purchased 2 zippy 3S, 20-30C, 5000mah lipos and have been running them in my e-revo. One pack was perfectly balanced, the other had one cell about half a volt lower than the other two. I have a charger that balances the lipos and when I'd charge them, I'd plug in the balancer (thinking it was supposed to balance). Today, I was running the car and I noticed the power seemed like it wasn't there. I was expecting that MM to kill the power but it never did. I brought it in, held the wing and gave it a few throttle pulls. Never turned off. I pulled the batteries and went to charge them. The one cell was at 2.6v. Within 30 seconds it powered up to 3.1V and the other two cells were at 3.6v. I found out last night that in order to balance, I had to use the balance part of the charger. I did this next and they were balanced in 15 minutes.

Question #1: Did I harm the battery? It doesn't appear that I did. There is no swelling and it wasn't any warmer than typical.

Question #2: Why didn't the ESC kill the power? My guess, it's on Auto Lipo. The ESC thought it was a 5S and not a 6S "thinking" there was more power to use. Lesson, turn off auto lipo?

Thanks in advance.

[What's_nitro?]

I would do a couple of C/D cycles on the bench and see how that cell behaves. Over-discharging doesn't put you in danger of a LiPo fire, but it can damage the cell irreparably.

As far as the MM goes, the Auto-LiPo will only detect the number of cells properly if you hook up a fully charged pack. The cell in question may have dropped voltage very quickly after coming off of the charger and caused the MM to detect 5, instead of 6, cells. With the pack fully charged, do you hear 6 beeps when you turn on the MM?

If you only use a 6s pack with it I would set the cutoff to 6s and not use the auto.

When I last ran the truck (Thursday), I ended the day before the ESC shut it down. In fact, I have yet to fully discharge the batteries by running the truck. I'll usually run it for 20-30 minutes, break something, and charge the batteries while I do other things. Today, I started the truck on the batteries from Thursday's run, so they were not fresh.

Regarding the beeps, I didn't know that the ESC beeps for the numbers of cells... really good to know. I'll be listening from here on out.

Regarding the cycling, for these packs, what should I discharge them at? I have yet to discharge any batteries with my "charger".

The next time I buy batteries (very soon), I'm going to pick up one of these for a "quick assesment" before running:
http://www.hobbycity.com/hobbycity/s...idproduct=6589
or
http://www.hobbycity.com/hobbycity/s...idproduct=7704

[lincpimp]

I do not trust the auto-lipo feature, as it really needs fully charged packs every time you use it. Sounds like it thought your somewhat discharged pack was 5s. I am sure that the pack is fine, just set your MMM (I am guessing you have a mamba monster, not a mamba max, the max will only do 4s reliably) with a specific lvc, for 6s 19.2v works well, 3.2v per cell.

Thanks, and yes, I have the Mamba Monster. I'm pretty sure that is what happened.

LOL... Now I know the difference between MM and MMM! I've been wondering since the V1 came out why they called it the MMM when a lot of post had MM. Figured it was a Toma(y)to Toma(h)to thing!

I'll update the software tomorrow before my next run.

[auto2]

chargers like hyperion( at least mine) cant balance a way out of balance pack during charge mode. they need balance mode only to balance a pack that far out.