Overcharged and Swollen

[Frank in Thailand]

Yes, I missed that small part.
"Will start to breakdown the organic electrolyte..."

Is a sentence that doesn't tell much. Actually nothing.
Not that it is dangerous to continue to use a cell if it has been charged over 4.2v.

When you drive your car one KM, almost all parts started to breakdown. That doesn't mean it's no longer safe.

The smell of electrolyte is absolutely not organic.
Some I could find:

The most commonly used electrolyte is comprised of lithium salt, in an "organic solution"

Deeper search shows something like"
electrode materials grafted aminophenyl, bromophenyl , and benzene-trifluoromethanesulfonylimide"

Organic is a strange word.

Gasoline is organic, so is Chlorine, Botox and Melons. Original from organic source..

Melons are in my dictionary organic, gasoline isn't.

Yours might be different.

You are missing the point.
There is absolutely not reason to believe that overcharge to +4.2 will increase the chances of an internal short.
Even if it would occur..
it will get warm.
lithium polymer will get so warm(hot) it will explode.
LiFePO4 just gets warm.
Unless there is flammable material that will combust at that temperature, there is absolutely no danger at all.

No more then lead acid battery, (who can explode....)


If the statement is that all battery should be in a safe environment that can handle accidents, yes. I fully agree.
You should not place any battery without protection under your bed and charge it.

If it's about increase risk, to a level that it's no longer safe to use...
Clear, I absolutely disagree.

That there is some damage, more lithium plating, less capacity and lesser cycle life, I think we both can agree.

In the last year, I have had this discussion several times.
People who have been exposed so many times to the warning of puffy lithium battery, that their eyes colour red when the read the both words. Not realize that LiFePO4 is not lithium polymer.

The ones who don't own LiFePO4, or have healty ones shout "danger!!!" And "replace"

A few months down the road when they have some pillows them selves, suddenly the danger isn't enough to replace.
As it will cost them money.

Most ideal, not for the environment but to have the most stable setup?
Sure, replace.

Talking about ideal:
You should only use laser welded compressed casing and laser welded busbars.
As that is how they are designed to be used.

All else is modification and increased danger of failure.

It's good to realize that the energy contained in a battery is dangerous, always.
In case of accident, there is a "bomb" waiting to go off.
(Figurative speaking)

 

[Gazoo]

According to this white paper, you might both be correct

You mean this one? Your file did not attach.

 

[Frank in Thailand]

@ereams65
Can you please share the paper?

file:///C:/Users/ereams/Downloads/energies-12-04652%20(1)

Edit:
Thanks @Gazoo for posting.

Good read for tomorrow.
Now 1.45Am...
Zzzzz

 

[ereams65]

@ereams65
Can you please share the paper?

file:///C:/Users/ereams/Downloads/energies-12-04652%20(1)

Edit:
Thanks @Gazoo for posting.

Good read for tomorrow.
Now 1.45Am...
Zzzzz

I think this will work;

https://www.mdpi.com/1996-1073/12/24/4652/pdf

 

[cinergi]

I must not be communicating well. I don't need to be convinced that LFP chemistry is safer than the rest. I know this and I'm not trying to state otherwise.

As far as I know, no one here has proven whether charging to 4.4+ overnight is a safety concern. So, because we don't know one way or the other, my personal opinion is to play it safe: don't use them, or use them where if they swell/leak/get very hot, you won't risk lives or property. That includes anywhere inside the house (not just under the bed). I am in no way presenting this as fact as an expert or otherwise.

 

[GSXR1000]

I have to ask if you where changing in series at 14v how did you hit 17?

 

[time2roll]

I would assemble them and cycle them hard a few times while monitoring balance, temperature and capacity.
If they work they work, otherwise post the issues.

 

[OldSmokey]

I have to ask if you where changing in series at 14v how did you hit 17?

I was using the same power supply that Will used in his how-to top balance video. I had it set at 14v with the amperage control turned all the way up(as suggested). Perhaps I misunderstood something, but when I woke up this morning the voltage on the charger had crept up on its own to about 18v. Perhaps it’s defective? Maybe that type of unit just needs regular babysitting.

 

[GSXR1000]

I was using the same power supply that Will used in his how-to top balance video. I had it set at 14v with the amperage control turned all the way up(as suggested). Perhaps I misunderstood something, but when I woke up this morning the voltage on the charger had crept up on its own to about 18v. Perhaps it’s defective? Maybe that type of unit just needs regular babysitting.

future reference... set the voltage and amps with the leads disconnected.. then connect and the voltage will drop till the current goes under 5a...

sound like you messed with the voltage while connected to the battery

 

[OldSmokey]

future reference... set the voltage and amps with the leads disconnected.. then connect and the voltage will drop till the current goes under 5a...

sound like you messed with the voltage while connected to the battery

That makes sense. I think you’re probably right. I must have adjusted it while connected.

 

[GSXR1000]

when I did my 8 270ah I just set on 3.65 and waited a 3 ½ days.. I figure I waited 3 months why worry about a week of charging

 

[GSXR1000]

also better wire

Thread 'Top balancing why proper wire' https://diysolarforum.com/threads/top-balancing-why-proper-wire.17168/

 

[Frank in Thailand]

It's safe to say (and all agree) that overcharging to 4.2 isn't dangerous or badly destructive.
Best is to stop at 3.65, it's OK to overshoot a bit.

Continuous charging to 4.2 (keep it there for days) absolutely is bad.
It will reduce the cycles as lithium plating occur in faster speed then you would want.

Going beyond 4.2, the safety, or long time 4.2, except the study shared by @ereams65 , not much information to go on.

It took some time to read.
In short:
-long time C0.25 at 5v is destructive for cycles, doesn't make it unsafe.
- short time C1 at 5v is destructive, but less destructive then above.
- short time C1 at 6v will kill your cell, without risk of explosion or thermal meltdown .
(I wasn't able to find the time frame used for long and short, must have missed it. If you see, please share)

Many people will have their opinion, I have a year experience with pillowing cells
And after a year of use, done capacity test on all 52 (48+4) 152Ah cells I have
Where the set of 4 have had way less cycles and wasn't pillowed.

Sure I'm not a laboratory.
And no way claim to be.

When it comes to real life experience and opinions based on the doom news from lithium polymer
(Exploding mobile phones, while in your jeans pocket...)
That happened.
Most people don't care, still keep their phones in an unsafe place when it explodes.
Your phone is enough to burn down the house, if it have fire food in the area. (Paper clothes, etc)

You should make up your own mind.
Where people are so careless about lithium when it suits them, and make strong suggestions about charging outside for LiFePO4..
Who will not explode or give fire....

They kind of lost it.
As that makes absolutely no sense.
Have an unprotected razor blade in your pocket and warn about how knifes can be dangerous....

And they aren't wrong. Knifes can be dangerous.
So can any energy storage product.
It it releases all the contained energy at once.. you don't want that under your bed.

I am crazy.
I charge my phone by my bedside, close to klamboe.
If the thing would explode...
We have a serious problem.
I find the risks of charging and possible explosion acceptable.
Same as my TV on standby, a behaviour that is know to have started countless house fires.

What can I say, I live dangerous.
I leave my USB charger in the socket, and many more potential dangerous behaviour.

All more dangerous then continue to use slightly bloated LiFePO4 cells.

All less dangerous then continue to use puffed Lithium polymer cells.

From the people who advised to only try outside...
How many have the same dangerous lifestyle as I have?
Leave USB charger (and other) in the socket, TV on standby and charge the known explotion dangerous mobile on a place where there is flammable material??

Please start with adjust your lifestyle before warning others.
Practice what you preach.

I have offered this several times, and will again:
If you have slightly puffed cells and are to afraid to use them?
Don't send them to landfill!!
For capacity above 100Ah I'm happy to pay for the transport costs, to grand them a long and happy healthy life.

 

[Luthj]

For non critical applications where cell failure and/or possible fire is mitigated , you may be able to continue to use them. They will need to be extremely well secured and compressed to the recommended pressure. They Need to be located well away from any flammable materials.

If failure is not an option , then they should be recycled.

A friend of mine recently overcharged cells to nearly 5 volts each. Using a stiff compression fixture, they were able to be successfully cycled with only minimal losses in capacity. I fully expect the longevity to be severely impacted, but for noncritical low load application they were still usable.

I have talked with the number of battery maintenance and install professionals. Regardless of the safety of LFP none of them would use those cells for any professional install.

I think it's obvious that fhorst is using motivated reasoning with regards to their opinions. So evaluate them as such.

 

[Frank in Thailand]

Lol..
I could say the same for all the naysayers.... Motivated reasoning...

Sure, "professional" installers need to give warranty.
And we all agree that it's not as good as it was.

We disagree on the potential danger.

All the reasoning I have heard of that it must be dangerous is from lithium polymer warnings.
The possible failures, the same.
Lithium polymer camp.

That's all fine.

Professional installers would not have used the cells without BMS, and without compression force.
This issue would not have occurred.

If I need to give warranty on the installation, sure, replace.
If it's for medical power source, needs to be up and running or otherwise people die...
Absolutely, replace.

Many of us use "old" discarded hospital LiFePO4 cells.
They are replaced everything 3-5 years.
That doesn't make them dangerous.

Just no longer suitable in that environment.

Your car can have a leak tire fixed.
Ambulance absolutely will get a new tire.
Race cars, the same.
Police, fire department, list of professional goes on.
For your car to go to work...
Not a problem at all.
Yet, if you ask a professional what is more safe, they will say a new tire.

OP isn't professional, and his RV energy isn't responsible for keeping him alive.

It's easy to say something is dangerous, and that it needs to be replaced.
Especially when it's not your money.

I know there is overwhelming proof that pillowed lithium polymer is dangerous.

Just as there is NO proof LiFePO4 is dangerous.

I'm always happy to learn. And yes, I'm that guy who asks "why?"
You all say it's dangerous... Why?
Because you where told it is.
By who? By lithium ion producers.
Lithium what? Lithium ion.
Ah.
And?
LiFePO4 is indeed lithium but not the kind you have heard all your life the warnings about.
So?
Next proof please!!
Not hearsay, real life experience that it is dangerous.

My real life experience with a year of usage of LiFePO4, battery packs are inside our strawbale house, and in out bedroom (in separate "room")

I'm not looking for a way to kill my family and myself.
I looked realistic at the facts.
Besides a ton of fear, there is no reason why they should give any problems, not anything more then non pillowed cells.

I have experience with a short in a 280Ah cell. (User error) and that wasn't spectacular at all.
Just 0.04v. no damages to surrounding cells, no overheating, NADA.

If you don't have this experience, I can understand the fears.
That's all they are. Fears.
Surrey you don't want fear to control your life.

As always, I really do like to learn.
And absolutely CAN (and often will) be wrong.
Please do provide proof.
Not personal opinions based on fear or stories.
If there is proof it's dangerous to use, for sure.
I love my family way too much to let them get harm by my mistakes.

Not following hearsay fear isn't a mistake.
Not following supported proof that it is dangerous is.

So please, do provide proof.

Without it, the naysayers are using "motivated reasoning"
(Lovely words)

 

[OnTheRoadAgain]

It must be said yet again........

Folks....PLEASE PLEASE PLEASE........

NEVER charge you LiFePO4 batteries without protection. That usually means with a BMS.

We all know what awful things can happens when you do things without protection.

 

[OldSmokey]

Lol. Glad I could help reinforce that lesson.

 

[Frank in Thailand]

BMS for 4, in an S16 setup doesn't make much sense to buy, and can be seen expensive to use for one time.

I've bought a bundle of the cheap S4 active Balancer, who does 1.2A max.

Charging with 20A, I use 5 to 8 of those small boys.
As soon as any of the light turn in, there is a 0.2v difference, and the cells should start to be monitored continuous.

With 5 or 8 (I have 2 sets) I can give it a few hours more on 10A
(Constant voltage phase already started, so not full 10A but deciding.

It would not have stopped this error where the CC/CV charger was set to 17v...
A BMS would.

Anyways, the small ones are dirt cheap, work like a charm, and can be used later per 4 cells (or 5 on a set of 16 with overlap) as additional Balance safety.

It's not a BMS.
Taking out one of the 4 positive leads will make a small pop and tiny magic smoke. (As @Will Prowse experienced)
As long as all the 5 wires are correctly mounted to the battery, before you plug in, and plugged out before you play with the wires, they are strong. And work!!

I bought on purpose the S4.
For assisting with 12v car battery chargers and place on the cells later.
If one should fail, just a small section will loose it's additional active balance, not the whole pack.
Besides that, 5 where cheaper then one S16

 

[Deleted member 9967]

Looking for an honest opinion here. I recently bought a set of 280ah EVE cells and really screwed up while trying to top balance. I had them sitting in parallel for about 4-5 days, trying to top balance to 3.6v. They really weren’t progressing(due to my small 5a power supply) and I guess I got a little impatient. I put them in series and tried to charge them up to 14v. After that I was gonna go back to parallel to finish it off. Well last night I went to bed with them around 13.5v. I guess they took off overnight and I woke up to 17.6v(I know, should’ve been using a BMS). Of course in the process, they swelled up.

I got the pack down to normal levels at this point. My question is whether or not they’re too far gone or too dangerous to use. Believe me, I’m sick over the situation.

To try to actually answer your question.
They can still be used. However their capacity is probably severely compromised.
Do a simple test to find the capacity and then use it accordingly.
For instance. I had three cells go bad on me. One is done. It simply can't hold a charge.
Two others can but no where near what they were rated for. I intend to use them on the side for lower capacity uses.
However, say you have a nice bank of 100 Ah cells. Lets say ten for arguments sake. Now half have been broken. So you capacity test those 5 broken ones and find that instead of 100 Ah you now have 70 Ah. Use them with the five good ones BUT understand that you now have ONLY a total of 70 Ah capacity instead of 100 Ah.
If you do this then it is possible that you may be able to continue to use the broken ones.

Do a top balance [being EXTREMELY careful of run away]. Next, only discharge them about 60 Ah. Charge them almost fully but not quite.
You could probably get 50 Ah out of them for a couple of years or so.

Not great, But at least still usable.

I hope this helps.

EDIT: I specifically use lifepo because it is fire safe.
So while they could vent and stink your place up. Thee is no danger of fire from the cells themselves. Just keep them from flammables in case they get very hot is all.

NEXT EDIT: For spelling.