LiPo battery good or bad!

Dmkkings

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For some reason when I store charge my Spectrum 3s LiPo battery, there is one cell that is always off by three or four volts! Like for example they will be 3.86, 3.85, and 3.82 volts. Then when I fully charge the battery and run it in my Arrma Felony, the Esc will go into low voltage cut off! Blinking red light! Then if I unplug and plug the battery back in and power the car back on it does the same thing! Runs fine for a couple of passes and then does the same thing! Does this mean that my LiPo is bad? And if so is there any way to fix the LiPo? I have only had this particular LiPo for a little over a year! Thank u for the feed back!
 

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For some reason when I store charge my Spectrum 3s LiPo battery, there is one cell that is always off by three or four volts! Like for example they will be 3.86, 3.85, and 3.82 volts. Then when I fully charge the battery and run it in my Arrma Felony, the Esc will go into low voltage cut off! Blinking red light! Then if I unplug and plug the battery back in and power the car back on it does the same thing! Runs fine for a couple of passes and then does the same thing! Does this mean that my LiPo is bad? And if so is there any way to fix the LiPo? I have only had this particular LiPo for a little over a year! Thank u for the feed back!
Those are 3-4 hundredths of a volt, which is pretty nominal. Don't know why lvc would kick on so quickly tho, as long as you're getting to actual full charge 1st. I hope some more knowledgeable folks will chime in
 

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Do you always run to LVC?
What is the voltage of the lipo after a typical run? What are the values per cell?
Does your charger measure IR (internal resistance?) If not, get one

No, a lipo can't be repaired, but without answers to above, nobody will be able to tell you if it's bad.
 

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Ok, that is a surefire way to kill your lipo.
Make sure your LVC is set to 3.4V or above and even than it's a risk. LVC is only there to protect the ESC from under voltage, it is not meant to protect the Lipo.

Dispose of it and get a new one, the constant running down to LVC causes internal irreparable damage that increases the internal resistance. That is like choking of a water hose and trying to put out a fire.

Again, without actually knowing if your cells are mismatched, there is no way to tell if it's the cause.

Get yourself a checker that has this function, careful, many clones out there that do not offer this functionality.
https://www.amazon.com/MaximalPower-Battery-Intelligent-Digital-Balancer/dp/B0799BB48V

It's not a precision instrument, but all cells should be roughly the same and below 5 mOhm. Always check when the lipo is fully charged. Values will differ across charge status.
My guess, 1 cell is at least double that of the others. That is a sure sign it's time to put it out of it's misery.

In the long run, get a charger that has this as a built-in function.
 

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Are you doing speed runs? If so what you are experiencing is voltage drop and it sounds like the voltage is dropping far enough and for a long enough time to trigger the lvc in the car.
 

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Do you always run to LVC?
What is the voltage of the lipo after a typical run? What are the values per cell?
Yes it always runs to LVC

Does your charger measure IR (internal resistance?) If not, get one

No, a lipo can't be repaired, but without answers to above, nobody will be able to tell you if it's bad.
Are you doing speed runs? If so what you are experiencing is voltage drop and it sounds like the voltage is dropping far enough and for a long enough time to trigger the lvc in the c
Are you doing speed runs? If so what you are experiencing is voltage drop and it sounds like the voltage is dropping far enough and for a long enough time to trigger the lvc in the car.
No I am not doing speed runs! For instance the LiPo is at storage and the Cell1 is at 3.87, Cell 2 is at 3.87, and Cell 3 is at 3.82! The battery is at 56% at storage. Even when the battery is fully charged there is that much of a difference in the cells! Like I said when I fully charge the battery and run it in my Fellony the Esc goes into LVC mode after a couple of minutes! Keep in mind I am running two 3s batteries. I am using a Spectrum S21 charger and battery!
 

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For some reason when I store charge my Spectrum 3s LiPo battery, there is one cell that is always off by three or four volts! Like for example they will be 3.86, 3.85, and 3.82 volts. Then when I fully charge the battery and run it in my Arrma Felony, the Esc will go into low voltage cut off! Blinking red light! Then if I unplug and plug the battery back in and power the car back on it does the same thing! Runs fine for a couple of passes and then does the same thing! Does this mean that my LiPo is bad? And if so is there any way to fix the LiPo? I have only had this particular LiPo for a little over a year! Thank u for the feed back!
As several others said, don't worry about the 10s of milivolts (.010). Even a good volt meter has tolerances. In the case of using a battery checker, there is no reference voltage so it uses some electronics to make the best guess. Which is about as accurate as a hurricane trimming the trees. Your battery charger should give you a better reading, but they they are still not precision instruments.

How much time is it to the first voltage cut off? The battery size, ESC and motor all make a difference. If you are running a high power/high current load on a 1500 mah battery, I wouldn't expect much run time. It may even cut out early because it just can't deliver the juice required for a heavy throttle finger.

Under normal conditions a battery being used will read a little lower than a battery that has been resting. For instance you might be getting below LVC (call is 3.4V/cell) under full throttle (high current draw). Then when you unplug and reconnect it, you reset the ESC, but also gave the battery some time to rest.
 

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For some reason when I store charge my Spectrum 3s LiPo battery, there is one cell that is always off by three or four volts! Like for example they will be 3.86, 3.85, and 3.82 volts. Then when I fully charge the battery and run it in my Arrma Felony, the Esc will go into low voltage cut off! Blinking red light! Then if I unplug and plug the battery back in and power the car back on it does the same thing! Runs fine for a couple of passes and then does the same thing! Does this mean that my LiPo is bad? And if so is there any way to fix the LiPo? I have only had this particular LiPo for a little over a year! Thank u for the feed back!
At the risk of asking what may be assumed to most, are you BALANCE charging? My 3s cells are off during the charge process also, but even out in the last part of the charging process. You only mentioned the storage charge readings so just wondering. Pardon my ignorance as I'm new to electrics.
 

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@Dmkkings, those "Smart" lipo(s) are not all that.
Get a lipo testor for out in the field to check them when you hit LVC.
Also, might want to check the gearing. If you changed it out. You can also drop the ESC Punch/Power setting down a notch, and re-evaluate. If pulling hard and sustained Thr. Trigger, you might even be starting to amp Cut. Reached the ESCs/ Lipos' limits?:unsure:
Once you hit LVC, in general, restarting the ESC will reset the LVC normally. But doesn't mean you should continue driving, IF the lipos are truly discharged. So its best to use a lipo testor right there on the spot to verify Lipo voltages across all the cells once LVC hits.
The best way to narrow down what is going on.
Like stated above, a negligeable 4/one-hundreths of a volt ( .004v) is not 4.0 volts. An actual 4.0 volt difference across a cell or 2, means a Bricked cell(s). Pack is junk in this case.
 
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