Having issues charging one of my new Lipos

Okay so I got 4 multistar 4s - 14.8v 10c 10000mah batteries and I rode my bike to try it out, was alot of fun etc, so they are discharged low had to wait a couple days for charger to finally come in cause ppl at FedEx are snails and now all my batteries except one will charge, at first I got Battery Error low voltage during battery check sop i watched a method on YouTube to resolve that was to set it as NiMH charging, and let it do its thing for a few minutes, so i did that that got rid of that issue so now it starts charging and about 5 seconds or so into it, it comes up with a Battery Vol Error: Cell connect. Any ideas why it does this? thanks, these batteries are new also and only been through 1 charge cycle so far and 2 discharges..

Sounds like a bad cell. The worst thing you can do is get a new pack and discharge it low then let it sit. I've had bad luck with some multistars failing in a year because of weak cells so you probably got unlucky.

That same battey also feels more fatter on the sides than the other 3 does that indicate anything?

That's "swelling" or "puffing". If you havent' used RC LiPo before (or at least have never had any problems with it) I highly recommend reading around in the various RC LiPo noob threads to prepare yourself for the various issues it can present, including puffing, swelling, dead cells right from the vendor, unprovoked fire, etc.

Some of the best battery threads should be linked in the Battery Technology subforum's Sticky Index thread, and then there's others like
https://endless-sphere.com/forums/viewtopic.php?f=14&t=19956
and
https://endless-sphere.com/forums/viewtopic.php?f=14&t=9170
and
https://endless-sphere.com/forums/viewtopic.php?f=14&t=52240
and
https://endless-sphere.com/forums/viewtopic.php?f=14&t=26621
and

Don't over discharge your lipos. It causes permanent damage. Consider that one ruined and get another battery.

Definitely a bad cell then if it's puffy. I treated my multistars very well and had a 50% failure rate at 13 months. Both packs had one puffy cell. In your case you definitely over drained it right off the bat and let it sit overly discharged. That will puff up cells almost every time.

Luckily multistars have a safer chemistry and don't tend to catch fire. It is a possibility though and you got lucky this time. Spend some serious time reading up on Lipo safety. If you F' up again it can result in a huge fire with badly burnt skin and/or serious property damage. Start checking all the cells to make sure they're balanced after charging and before using them or... I use a cheap voltage meter with a low voltage alarm from HK on the balance lead of all my lipos. Under $2 each. That way if one of my 24-48 cells goes out during a ride I can pull some packs and not blow them all up at once after one cell explodes.

You should stop discharging Multistars when the cells get down to 3.6V to keep them balanced.
Its possible to take them to 3.5V if you are desperate but it will definately unbalance the cells.
You need a wattmeter or at the very least a set of cell alarms to avoid damaging any more cells.
I always put mine on the charger as soon as I finish a ride and take them up to 3.85V for storage even if they are going to be used the next day.
I charge them to 4.1V per cell on the day they are being used and mine are 2 years old now with around 200 full cycles on them and still good as new.
I have 6 of 6S 16Ah and 4 of 4S 16Ah .

G'day Cody,
Just want to add my bit and I hope it helps.
About two months ago I over discharged the RC Lipos in my beach cruiser. Put them on the charger as soon as they cooled & got the "cell voltage error" as you did. I ignored it & charged them anyway. This was the result;

The batts were in that pannier.
Worth thinking about. I can't stress enough how careful you have to be with LiPo. I'd been using them for 3 years & thought I knew what I was doing. I should have checked each cells voltage & balance charged while CONSTANTLY monitoring cell voltage & temps.

The best mistakes to learn from are others. Please learn from mine.
AussieRider.

cody196 said:

Okay so I got 4 multistar 4s - 14.8v 10c 10000mah batteries and I rode my bike to try it out, was alot of fun etc, so they are discharged low had to wait a couple days for charger to finally come in cause ppl at FedEx are snails and now all my batteries except one will charge, at first I got Battery Error low voltage during battery check sop i watched a method on YouTube to resolve that was to set it as NiMH charging, and let it do its thing for a few minutes, so i did that that got rid of that issue so now it starts charging and about 5 seconds or so into it, it comes up with a Battery Vol Error: Cell connect. Any ideas why it does this? thanks, these batteries are new also and only been through 1 charge cycle so far and 2 discharges..

Click to expand...

Don't you have a Low Voltage Cutoff??? Never use LiPoly without one!!!
Whether or not a cell is perm. damaged I cannot say, but there are some things you might try to bring it back.
You haven''t told us what charger you have, so depending on the charger, the low cell may be making the overall Voltage too low for the programmed cell count. That's what you did when you changed chemistrey, you lowered the Voltage the charger wanted to see. If you had the balance tap connected, that is probably why it shout off again. Try it again w/out the balance tap.
OR
If you are trying to charge 4S, try bulk charging @ 3S for a SHORT time without connecting the balance connector. Don't over do it, them go back to 4S and try it(and read the cell Voltage).
In the past(before I got a little smarter), I rigged a harness to charge one cell thru the balance tap w/ the charger on 1S. If your charger is capable, you might try that.

KINNINVIEKID said:

You should stop discharging Multistars when the cells get down to 3.6V to keep them balanced.
Its possible to take them to 3.5V if you are desperate but it will definately unbalance the cells.
You need a wattmeter or at the very least a set of cell alarms to avoid damaging any more cells.
I always put mine on the charger as soon as I finish a ride and take them up to 3.85V for storage even if they are going to be used the next day.
I charge them to 4.1V per cell on the day they are being used and mine are 2 years old now with around 200 full cycles on them and still good as new.
I have 6 of 6S 16Ah and 4 of 4S 16Ah .

Click to expand...

+2!
A fixed Low Voltage Cut-off is much better than a alarm. Most 48V controllers have a 42V LVC, which is 3.65V/cell when running 12S, perfect.
That's one of the reasons why I run 12S.

motomech said:

KINNINVIEKID said:

You should stop discharging Multistars when the cells get down to 3.6V to keep them balanced.
Its possible to take them to 3.5V if you are desperate but it will definately unbalance the cells.
You need a wattmeter or at the very least a set of cell alarms to avoid damaging any more cells.
I always put mine on the charger as soon as I finish a ride and take them up to 3.85V for storage even if they are going to be used the next day.
I charge them to 4.1V per cell on the day they are being used and mine are 2 years old now with around 200 full cycles on them and still good as new.
I have 6 of 6S 16Ah and 4 of 4S 16Ah .

Click to expand...

+2!
A fixed Low Voltage Cut-off is much better than a alarm. Most 48V controllers have a 42V LVC, which is 3.65V/cell when running 12S, perfect.
That's one of the reasons why I run 12S.

Click to expand...

I agree with everything you say.. But doesn't a 42v LVC, with 12s give you 3.5v per cell..??
You need an LVC of 43.8v, to end up with 3.65v on your 12s pack..
Interestingly, the KT Kunteng controllers when used with their LCD3 or LCD6 display, allow you to increase the 42v LVC by an additional 1.5v, so pretty much ideal for 12s of Lithium pouch cells..

No, in reality, a 42 V LVC results in an AVG. 3.65 V for all the cells. That's because one or more or the cells has just started to stray(drop) and the effects of sag under load.
If the rider tries to "squeeze every drop" out of the battery be taking off again after the LVC re-sets, the avg. of the cells can be lowered w/ even more straying(not advised).
I hit the LVC more often than most because I use 2 different packs on my 2WD and the frt. one is small. I always ck. the cells on the shut-off pack when I get home and if I stop @ the first LVC-trip, I might have one or two cells @ 3.5V or 3.55V w/ the rest @ 3.65V. At this point, I can just start to bulk charge and they will come together during the cycle.
If I have tried to force more out of the pack, I could have cells all the way down to 3.3V Not good, and even taking them down to 3.65V probably takes a little of life out of the pack.

Of the two most common LVC values for the most used controllers, 42V w/ 12S LiPoly is the best match.
I have used the 31V LVC and it is way to low w/ 10S(3.10V), So one is forced to use 9S, which is a little too low(3.44V), but workable if one is careful.

When the sine-wave controllers w/ their "auto-ranging LVC's came out, I tried various LiPoly packs, but never could get controllers to "play nice" w/ the odd LiPoly voltage values.
The newer ones may work better w/ LiPoly.

The controller i Got is 430 amps and does have a LVC at 42v i think. However its a 48v - 72v controller and i ran it on 60v pack so 4x 4s 14.8v lipos and I got an Imax B6 Charger AC

cody196 said:

The controller i Got is 430 amps and does have a LVC at 42v i think. However its a 48v - 72v controller and i ran it on 60v pack so 4x 4s 14.8v lipos and I got an Imax B6 Charger AC

Click to expand...

430 amps is a typo right? multistars are only good for maybe 3c discharge for 5-10 minutes. 5c is pushing it for extended times I've found.

My BBSHD and BBS02 both have an LVC of 42V but as I use both 12S and 14S on a ride (seperately) I dont ever get that low and use a CA to monitor the voltage and always aim for home well before running out of battery.
Of course carrying 64Ah helps as I can ride 120 miles or more before dropping below 3.6V per cell.

Yes that was a typo, it pulls 40 amps maximum, i think it averages between 35 - 38 amps