7.4V 5000mah Turnigy lipo puffed up!
08-21-2010, 08:12 AM
#1
7.4V 5000mah Turnigy lipo puffed up!
I was running two of these lipos in my BL summit with Novak system and one of the Lipos puffed up! Its at least my 10th run and the voltage cut off has worked fine always. I have now ordered a new lipo but dont want the same thing to happen, what might have caused this? The charger says the battery is at 4.04v, well below the 2S cut off...
Thanks
Thanks
08-21-2010, 10:18 AM
#3
Is there any way to bring it back to life? The charger isnt charging it due to low voltage!
08-21-2010, 10:34 AM
#4
Not safe but, here is what I have done to bring it back. If you have a charger that does all types of battery and has a LED display that shows voltage of the battery. Plug just the charger lead and not the balancing plug. Put the charger to NiMH and charge it at 1.0 amps until your battery shows above 6.0 volts but no more than 2 - 3 minutes on this charge. Once you kick the battery above this, then you can put the charger back to Lipo and ballance it. It's worked for me in the past. Hope that helps.
08-21-2010, 12:24 PM
#6
Your lipo puffed cause you overdischarged it, 4.04v is 2.02v/cell and cells should never go below 3v/cell or 6v for a 2S.
You can try charging it as NiMh, but I would use a lower rate like 0.2 - 0.3amp so there is as little chance as possible that charging could cause more swelling. If you see it swelling more while trying to get the voltage back up, stop charging immediately and remove the lipo to somewhere it can't hurt anything if it goes off.
The lower charging rate will make the voltage come up slower and more evenly, let it charge until its comfortable over 6v. I usually try for 6.1 or 6.2v before I stop and then finish charging it as a lipo using lipo balance charge mode. You might be best not charging it at a full 1C rate thios next time too and watch it carefully while charging as a lipo for more swelling.
If you do manage to save it, its prob been damaged by dropping to that low of a voltage, so don't be surprised it isn't as strong as the other. The big ques is why the lvc did not kick in and stop. You didn't see it slow down even a little? I can see mine slowing before the lvc hits and thats when I stop. I wouldn't run again until you know why the lvc didn't work.
You can try charging it as NiMh, but I would use a lower rate like 0.2 - 0.3amp so there is as little chance as possible that charging could cause more swelling. If you see it swelling more while trying to get the voltage back up, stop charging immediately and remove the lipo to somewhere it can't hurt anything if it goes off.
The lower charging rate will make the voltage come up slower and more evenly, let it charge until its comfortable over 6v. I usually try for 6.1 or 6.2v before I stop and then finish charging it as a lipo using lipo balance charge mode. You might be best not charging it at a full 1C rate thios next time too and watch it carefully while charging as a lipo for more swelling.
If you do manage to save it, its prob been damaged by dropping to that low of a voltage, so don't be surprised it isn't as strong as the other. The big ques is why the lvc did not kick in and stop. You didn't see it slow down even a little? I can see mine slowing before the lvc hits and thats when I stop. I wouldn't run again until you know why the lvc didn't work.
08-21-2010, 12:28 PM
#7
Toss it, and don't risk hurting someone, your self, or risk burning down your rc or house. It's a battery, its a hobby chock it up as a loss, stay safe and move on.
08-21-2010, 12:49 PM
#8
Your lipo puffed cause you overdischarged it, 4.04v is 2.02v/cell and cells should never go below 3v/cell or 6v for a 2S.
You can try charging it as NiMh, but I would use a lower rate like 0.2 - 0.3amp so there is as little chance as possible that charging could cause more swelling. If you see it swelling more while trying to get the voltage back up, stop charging immediately and remove the lipo to somewhere it can't hurt anything if it goes off.
The lower charging rate will make the voltage come up slower and more evenly, let it charge until its comfortable over 6v. I usually try for 6.1 or 6.2v before I stop and then finish charging it as a lipo using lipo balance charge mode. You might be best not charging it at a full 1C rate thios next time too and watch it carefully while charging as a lipo for more swelling.
If you do manage to save it, its prob been damaged by dropping to that low of a voltage, so don't be surprised it isn't as strong as the other. The big ques is why the lvc did not kick in and stop. You didn't see it slow down even a little? I can see mine slowing before the lvc hits and thats when I stop. I wouldn't run again until you know why the lvc didn't work.
You can try charging it as NiMh, but I would use a lower rate like 0.2 - 0.3amp so there is as little chance as possible that charging could cause more swelling. If you see it swelling more while trying to get the voltage back up, stop charging immediately and remove the lipo to somewhere it can't hurt anything if it goes off.
The lower charging rate will make the voltage come up slower and more evenly, let it charge until its comfortable over 6v. I usually try for 6.1 or 6.2v before I stop and then finish charging it as a lipo using lipo balance charge mode. You might be best not charging it at a full 1C rate thios next time too and watch it carefully while charging as a lipo for more swelling.
If you do manage to save it, its prob been damaged by dropping to that low of a voltage, so don't be surprised it isn't as strong as the other. The big ques is why the lvc did not kick in and stop. You didn't see it slow down even a little? I can see mine slowing before the lvc hits and thats when I stop. I wouldn't run again until you know why the lvc didn't work.
What is the proper way to discard a Lipo battery?
08-21-2010, 02:30 PM
#9
a few things....if you are going to try the above I would recommend in a fire proof sack, or watching very closely. If you are going to throw it away you need to discharge it as much as possible and then put it in a bucket of high conc. salt water that will discharge it to 0v. Then it is safe to throw it away.
08-21-2010, 05:04 PM
#11
For discarding, what's now recommended is to discharge one to 0V using a auto tail light bulb. It can puff doing this, so be careful.
Once at zero volts, cut leads off and put in the trash. More discussion here -
http://www.rcgroups.com/forums/showt...light=disposal
Once at zero volts, cut leads off and put in the trash. More discussion here -
http://www.rcgroups.com/forums/showt...light=disposal
08-21-2010, 08:24 PM
#13
I've had to 'rescue' several lipos from a low voltage condition, but all were new and it was a pretty good assumption that they were prob not damaged. I don't think its a big deal trying with yours thats been overdischarged while still almost new. Just do it where its safe and watch it closely.
I'd try to revive it. I'd also have no prob running it with another lipo that didn't have probs like your other. First run out, stop at 5 min and check lipo temps, if this one is noticeably hotter than the other, then I would replace it. I'd still use this one by itself , but in something else. As long as it doesn't swell more when discharging/charging its useable.
I'd try to revive it. I'd also have no prob running it with another lipo that didn't have probs like your other. First run out, stop at 5 min and check lipo temps, if this one is noticeably hotter than the other, then I would replace it. I'd still use this one by itself , but in something else. As long as it doesn't swell more when discharging/charging its useable.
08-21-2010, 08:29 PM
#14
I've had to 'rescue' several lipos from a low voltage condition, but all were new and it was a pretty good assumption that they were prob not damaged. I don't think its a big deal trying with yours thats been overdischarged while still almost new. Just do it where its safe and watch it closely.
I'd try to revive it. I'd also have no prob running it with another lipo that didn't have probs like your other. First run out, stop at 5 min and check lipo temps, if this one is noticeably hotter than the other, then I would replace it. I'd still use this one by itself , but in something else. As long as it doesn't swell more when discharging/charging its useable.
I'd try to revive it. I'd also have no prob running it with another lipo that didn't have probs like your other. First run out, stop at 5 min and check lipo temps, if this one is noticeably hotter than the other, then I would replace it. I'd still use this one by itself , but in something else. As long as it doesn't swell more when discharging/charging its useable.
08-24-2010, 02:42 AM
#15
Thanks guys! Will let you know how it goes!