Can voltage drop damage a lithium battery?

lgbattery

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Noob question, exactly whats in the title. Couldn't find an answer after a while of searching.

Lets say I have a Li-Po cell rated for 2.2-4.2V, if the cell drops below the 2.2v minimum while under load and returns back to a 3.7v nominal when the load is removed, can this cause damage to the cell?
 
The answer depends on the battery chemistry. 3.7 V Sounds like you are over working that cell or it’s weak. The heavier load you put on the cell will shorten the life of the cell. All Lithium batteries are slowly dying how much abuse is a good question. 2.2 volts is really low for Lipo’s i’ve never seen a Lipo drop to 2.2 V and then return all the way up to 3.7V


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lgbattery said:
Lets say I have a Li-Po cell rated for 2.2-4.2V, if the cell drops below the 2.2v minimum while under load and returns back to a 3.7v nominal when the load is removed, can this cause damage to the cell?
First-off your Li-Po question shouldn't be a real-life application (IMO) as it's definitely abusive (IMO). With a sustained burst taking it below 2.2v may not significantly puff the cell due to tight shrink wrap, but it will definitely diminish its cycle life. A sustained burst +5 seconds could result in a fire/explosion :bolt:

The fact that the bounce back voltage may return to 3.7v from below 2.2v (after an hour rest) is an indication of the extreme burst punishment for those few seconds. High performance Li-Po's have a burst rating as high as 45C-50C so it's feasible the bounce back voltage could be as high as 1.0v (2.0v to 3.0v) after a 10 minute rest and 1.7v (2.0v to 3.7v) after 60 minutes.

Such abuse ("below the 2.2v minimum") means you may be buying another $65 high performance Li-Po sooner than you had hoped. Dropping below 2.2v for 3-5 seconds of burst during every discharge cycle is IMO abusive because it dramatically shortens the cycle life ... but whatever turns your crank.
 
lgbattery said:
Lets say I have a Li-Po cell rated for 2.2-4.2V, if the cell drops below the 2.2v minimum while under load and returns back to a 3.7v nominal when the load is removed, can this cause damage to the cell?
Yes.

In addition you are likely exceeding the rated discharge limit for the cell if it's dropping that low.
 
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