How dangerous are swollen LiFePo4 cells received from AliExpress ?

elvis_asaftei

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Boot103

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I'm not too sure I was asleep when it happened. The smoke alarm woke me :/

The cells were fine when I top balanced / capacity tested. Although they were quite swollen. I thought this was normal.
  • The cell swelled up so much it internally damaged and shorted
  • My BMS may have failed causing over voltage to the cell.
They are the only two things I can think of.

I bought a YR1035+ resistance tester and will test the rest of the cells and report back.
 

elvis_asaftei

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I'm not too sure I was asleep when it happened. The smoke alarm woke me :/

The cells were fine when I top balanced / capacity tested. Although they were quite swollen. I thought this was normal.
  • The cell swelled up so much it internally damaged and shorted
  • My BMS may have failed causing over voltage to the cell.
They are the only two things I can think of.

I bought a YR1035+ resistance tester and will test the rest of the cells and report back.

This is what they answered to me and they refuse to replace damaged batteries.
I opened a dispute and I will contact the authorities for fraud.

pwod answer swollen battery.jpg
 

elvis_asaftei

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I would compress the cells as recommended and see what goes.
What method do you recommend to use and how to calculate exact force required ?
I tried manual and duct tape and it is not possible because of very higher pressure inside as seen in safety valves that are swollen too.

thank you
 

time2roll

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Many posts show using aluminum or wood plates with threaded rod. Need to search to get some torque values.
 

elvis_asaftei

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Interesting, thank you.

we need to compute torque on each nut so total force is not over 12 psi because 18 psi will destroy the cell and crack the safety valve.

but from why I see the valve is already swollen at maximum and I suspect that pressure inside is already at 15 psi, so if we do as you say with just 3psi of force applied will have the valve explode and release electrolyte gas that is toxic.

what do you think ?

thank you .
 

Boot103

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Interesting, thank you.

we need to compute torque on each nut so total force is not over 12 psi because 18 psi will destroy the cell and crack the safety valve.

but from why I see the valve is already swollen at maximum and I suspect that pressure inside is already at 15 psi, so if we do as you say with just 3psi of force applied will have the valve explode and release electrolyte gas that is toxic.

what do you think ?

thank you .
I was in the gas for about 5 mins. Its not that bad.

Just do it outside.
 

Boot103

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do you know what the electrolyte gas has in composition ? i know it is toxic, in time ...
I got checked over by the ambulance. I think Hydrogen Chloride is what they said.

I'm not saying to breath it in lol. Just do it outside and you will be fine.
 

elvis_asaftei

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I got checked over by the ambulance. I think Hydrogen Chloride is what they said.

I'm not saying to breath it in lol. Just do it outside and you will be fine.

lol, you asked for the ambulance. Was an explosion or just slowly gas release ?
 

Boot103

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lol, you asked for the ambulance. Was an explosion or just slowly gas release ?
I would say fast gas release haha. Loads of it and only one battery vented.

Yeah for sure. I was worried about me inhaling the gas. It smells really bad.
 

time2roll

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Interesting, thank you.

we need to compute torque on each nut so total force is not over 12 psi because 18 psi will destroy the cell and crack the safety valve.

but from why I see the valve is already swollen at maximum and I suspect that pressure inside is already at 15 psi, so if we do as you say with just 3psi of force applied will have the valve explode and release electrolyte gas that is toxic.

what do you think ?

thank you .
Best shot is to go slow. I would discharge the cells to 3 volts for better chance of reabsorbing the internal gas. Maybe one turn per day on a pack of 4 until you get the bus bar on.

If you think excessive heat during shipping may have caused the issue consider chilling a set of 4 in the fridge before you start compression.

And by all means do not lean over the top of the battery as you tighten them. Stay upwind or have a fan blowing and use a long extension to put a turn on the screws.

Just some random thoughts. I have not been through this process.
 

curiouscarbon

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And by all means do not lean over the top of the battery as you tighten them. Stay upwind or have a fan blowing and use a long extension to put a turn on the screws.

Just some random thoughts. I have not been through this process.
+1 Ensure Ventilation !☀️
 

elvis_asaftei

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You'll need a really big shovel to move that amount of bulls**t.

yes, that is PWOD, i paid and waited for 115 days and received 144 cells. 32 cells from them do not have QR code and text on cell label is “product 300” and what is interesting is that the ones without QR are less swollen.
This leads me to the conclusion that cells were sent like that already swollen otherwise swollen effect would have been visible also to cells without QR code.

DB5ABEC2-9403-440D-8E0E-5C9621477AF5.jpeg
 

houseofancients

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yes, that is PWOD, i paid and waited for 115 days and received 144 cells. 32 cells from them do not have QR code and text on cell label is “product 300” and what is interesting is that the ones without QR are less swollen.
This leads me to the conclusion that cells were sent like that already swollen otherwise swollen effect would have been visible also to cells without QR code.

View attachment 57519
elvis, i am sure i am not the only one getting really frustrated here.
all you do is complain...

let me make it simple and prefect clear to you :

1. you did not recieve what you ordered, party because YOU did not do your due dilligance
2. you informed the seller
3. they aren not going the refund you
4. talk to your bank / credit card company and have them refund you
5. set aside these cells ; do not use them ; i am sure when seller finds out the have no money they will tell you what to do with them.
6. use the refund to order new cells from a reputable source like amy

for the love of god man, how difficult is this to understand ?

you complaining about this company here will not change your situation, nor get your money back

</end rant>
 
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