3.2 volt packs arrived with low voltage

[SeanWatts]

I ordered a bunch of 3.2v cells. I ordered them at different times, as I could afford them. Now I am ready to assemble them in 24 volt batteries, so I put a voltage meter on them, before I top balance them. Below are the voltage readings.

.009
.035
.046
.233
.259
1.463
2.033
2.538
2.656
2.938
3.098
3.203
3.208
3.209
3.209
3.212

I would have called the business, but they don't have a phone number listed. I have emailed them, and the last response I got said "You want to charge each up to 3.65V and then hook them up in parallel". That was 8 days ago, and they have not responded to my reply. I do not want to mention the business name, as I want to give them a chance to do the right thing.

Wouldn't the cells that are reading below 2, or better yet the ones below 2.5 be replaced?

 

[timselectric]

Those are some scary low readings.
I would watch them closely, while trying to charge them.
Anything below 2.9v is highly susceptible to permanent damage.

 

[SeanWatts]

Those are some scary low readings.
I would watch them closely, while trying to charge them.
Anything below 2.9v is highly susceptible to permanent damage.

That is what I was thinking. Even if they take a charge, they will likely never have the capacity that they should.

 

[timselectric]

That is what I was thinking. Even if they take a charge, they will likely never have the capacity that they should.

I agree

 

[SeanWatts]

I agree

So, the place that I ordered them from should replace them, correct?

 

[timselectric]

So, the place that I ordered them from should replace them, correct?

That would depend on how long you had them.

 

[740GLE]

That would depend on how long you had them.

And how they were stored.

Quality cells shouldn’t have an issue sitting idle for a while, but then again quality cells are rarely bought by DIY people due to cost.

 

[SeanWatts]

That would depend on how long you had them.

These are the order dates.

2/18/22
1/6/22
10/10/21
8/19/21

 

[timselectric]

Did you test the voltages, as they arrived?
Were they dead on arrival, or have they discharged in the time since you received them.

 

[SeanWatts]

And how they were stored.

Quality cells shouldn’t have an issue sitting idle for a while, but then again quality cells are rarely bought by DIY people due to cost.

They where all still in the boxes that they shipped in. Two of the orders, were in my RV, and two orders where in my enclosed trailer. It has been over 90 degrees where I live, but my enclosed trailer has decent ventilation, and is usually cooler inside than out. My RV has been plugged in and the AC kicks in at 82 when I am not in it, and cooler than that when I am hanging out in it.

I would not think those temps would cause a problem.

 

[SeanWatts]

Did you test the voltages, as they arrived?
Were they dead on arrival, or have they discharged in the time since you received them.

I did not. In hindsight, I should have.

 

[sunshine_eggo]

These are the order dates.

2/18/22
1/6/22
10/10/21
8/19/21

Ratings for grade a cells tend to be < 1-3% charge loss/month. Almost impossible to believe that high quality cells would shit the bed. I let 9 cells sit for 5 months, and they only lost a very small % of their charge.

 

[timselectric]

It's impossible to know how long they sat, after they were boxed and before they were shipped.
All that you can do is contact the seller and cross your fingers.

 

[740GLE]

What’s the QR codes for manufacture dates?

 

[SeanWatts]

What’s the QR codes for manufacture dates?

No qr code, or manufacture date. They are 3.2v 100ah packs of 32640 cells.

 

[sunshine_eggo]

No qr code, or manufacture date. They are 3.2v 100ah packs of 32640 cells.

Very very bad sign. There likely is one, or it's scratched off. The black plastic cover on top is basically one-sided tape, and they are often under there.

 

[RCinFLA]

LFP cells that have sat below 1.0v for some time will grow metal dendrites that will cause leakage and eventually short through cell separator.

Be careful on any charging attempt and start out with low current, <0.02 C(A) rate, until they get above 2.5v. If they have significant dendrite shorts they will not rise in voltage with the low charge rate. If they do have significant dendrite shorts and you charge at high current they will get hot and burst.

 

[SeanWatts]

Very very bad sign. There likely is one, or it's scratched off. The black plastic cover on top is basically one-sided tape, and they are often under there.

These are not prismatic cells. No qr code. Here is a pic from when I was top balancing some of the good ones.

 

[Bud Martin]

I have seen those pack before from one of the member, they are from batteryhookup.

Just purchased 4 BATTERY HOOKUP 3.2V 100ah MODULES

Hey guys, New here! I have been researching for a couple months (new to solar and battery tech), and am planning a solar system for a shed/yard lighting, and was thinking about ordering 2 of the 4 packs to make a 24v battery. For this, would I just use a Daly 8s 24v bms? What do I use to top...

diysolarforum.com

They are 32650 (I have never heard of 32640) cells connected in parallel.

 

[mmame]

If I were you, I would discard all batteries below 2.5V - for safety reasons. And yes, those batteries are crap.