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New LiFePo4 cell arrived with low voltage. Is it bad?

forscience

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I just got my shipment of 4 "new" prismatic LiFePo4 cells rated at 3.2V each. However, one of them is only at 0.9V when I measured them. Is that cell permanently damaged or can I try to top balance it with the other cells and it'll be ok?
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However, one of them is only at 0.9V when I measured them. Is that cell permanently damaged or can I try to top balance it with the other cells and it'll be ok?
That is bad.
Don't try to charge yet, especially don't attempt a parallel top balance.
Are any of the cells bloated?
Are all the vents intact?
Do you smell or see any electrolyte?
The electrolyte is toxic so if you see or smell electrolyte get your ppe on and get the cells out of your living space.
 
That is bad.
Don't try to charge yet, especially don't attempt a parallel top balance.
Are any of the cells bloated?
Are all the vents intact?
Do you smell or see any electrolyte?
The electrolyte is toxic so if you see or smell electrolyte get your ppe on and get the cells out of your living space.
No cells are bloated and I do not smell anything. The measurement for each cell were: 3.4V, 3.4V, 3.3V, 0.9V.
 
No cells are bloated and I do not smell anything. The measurement for each cell were: 3.4V, 3.4V, 3.3V, 0.9V.
I suggest you charge the low cell individually at low current ~1 amp until it gets up to ~2.8 volts.
Then you can increase the current.
How many amps is your benchtop power supply rated for.
The fact that 2 cells are 3.4 volts and one is 3.3 is not a good sine either.
Were these cells advertised as brand new grade A?

The reason I advise you to charge them individually is the low one could "dead short" and take the other cells in parallel to hell with it.
@sunshine_eggo
 
I suggest you charge the low cell individually at low current ~1 amp until it gets up to ~2.8 volts.
Then you can increase the current.
How many amps is your benchtop power supply rated for.
The fact that 2 cells are 3.4 volts and one is 3.3 is not a good sine either.
Were these cells advertised as brand new grade A?

The reason I advise you to charge them individually is the low one could "dead short" and take the other cells in parallel to hell with it.
@sunshine_eggo
Yes, they are advertised as new grade A cells. My DC power supply is rated for 10A max and each cell is rated for 100Ah.

1) so you think that the 0.9V cell is still salvageable by charging it alone? Will it's capacity be reduced having sat at such a low voltage?
2) If I do charge the 0.9V cell up to 2.8V, can I then top balance it along with the other 3 cells?
2) The voltage window for these cells in the description is 2.3 - 3.65 V. So do I need to worry about the difference between the 3.4V and 3.3V cells? Will there be any issues if I went ahead and top balanced them?(assuming the 0.9V cell is at 3.4V or 3.3V)
3) by advising to charge them individually, do you mean charge all 4 cells individually? or just the 0.9V cell prior to top balancing all 4 together?
 
Yes, they are advertised as new grade A cells. My DC power supply is rated for 10A max and each cell is rated for 100Ah.

1) so you think that the 0.9V cell is still salvageable by charging it alone? Will it's capacity be reduced having sat at such a low voltage?
Probably not salvageable but its worth a try.
2) If I do charge the 0.9V cell up to 2.8V, can I then top balance it along with the other 3 cells?
I suggest charging each cell individually to 3.65 volts.
That is functionally equivalent to a parallel top balance.
If it was me I would let them sit for a month to see how much each one settles.
2) The voltage window for these cells in the description is 2.3 - 3.65 V. So do I need to worry about the difference between the 3.4V and 3.3V cells? Will there be any issues if I went ahead and top balanced them?(assuming the 0.9V cell is at 3.4V or 3.3V)
Yes I would worry.
I these were advertised as grade a brand new cells you have been ripped off.
Even the commodity A- cells arrive 3.295-3.3 volts.
3) by advising to charge them individually, do you mean charge all 4 cells individually? or just the 0.9V cell prior to top balancing all 4 together?
Yes all 4 cell individually.
You didn't answer my question about whether these cells were sold to you as brand new grade a cells.
If it was me I would try to get my money back.
1 or more of your cells are very likely crap.
Possibly all of them.
 
Probably not salvageable but its worth a try.

I suggest charging each cell individually to 3.65 volts.
That is functionally equivalent to a parallel top balance.
If it was me I would let them sit for a month to see how much each one settles.

Yes I would worry.
I these were advertised as grade a brand new cells you have been ripped off.
Even the commodity A- cells arrive 3.295-3.3 volts.

Yes all 4 cell individually.
You didn't answer my question about whether these cells were sold to you as brand new grade a cells.
If it was me I would try to get my money back.
1 or more of your cells are very likely crap.
Possibly all of them.
Here's the listing(https://www.ebay.com/itm/115016791435). I guess it doesn't say "New", but the price I think is on the cheaper end($100 per cell) so if that's worth it for a cell with 3.4V still then I'm ok with it. So why would a 3.4V cell be bad quality? This is my first time buying a lithium battery.
 
As I said before new cells typically arrive at 3.295-3.3 volts.
Since 2 of your cells arrived at a voltage at least 100mv higher than "shipping" voltage, I suspect they are returns.
Further to that...
3.4 volts is pretty close to full resting voltage.
Full cycle for an lfp cell is 2.5-3.65 volts.
 
Further to that...
3.4 volts is pretty close to full resting voltage.
Full cycle for an lfp cell is 2.5-3.65 volts.
Is full resting voltage at 3.4 volts ok? I'm just wondering if it's worth trying to return given the $100 per cell price. At the moment, I plan to return the 0.9V cell.
 
Is full resting voltage at 3.4 volts ok?
3.4 is ok.
The problem is you don't know how long those cells have sat full.
Its less than ideal to leave a cell full for extended periods.
I'm just wondering if it's worth trying to return given the $100 per cell price. At the moment, I plan to return the 0.9V cell.
The fact that they sent you 1 cell way below dead empty and 2 that are probably full is not good.
The vendor probably won't see it that way though.
Possibly because they don't know what they are doing or they don't care.
 
3.4 is ok.
The problem is you don't know how long those cells have sat full.
Its less than ideal to leave a cell full for extended periods.

The fact that they sent you 1 cell way below dead empty and 2 that are probably full is not good.
The vendor probably won't see it that way though.
Possibly because they don't know what they are doing or they don't care.
Thanks for your help, I learned quite a bit. I will just return the 0.9V one.
 
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