Over charged lifepo4

[Dunndeal]

I’ve heard almost everyone destroys their first set of batteries. I believe I’ve done it by over charging my lifepo4 90ah. 5 of 8 cells are very swollen. Very swollen. 2 of the 5 has had the vents covers blown off. Oddly enough all of the eight cells are holding a charge.
I read that some of the swelling can be reduced by applying pressure of the sides. If I could save them great. If not it’s just lessons learned

 

[fafrd]

I’ve heard almost everyone destroys their first set of batteries. I believe I’ve done it by over charging my lifepo4 90ah. 5 of 8 cells are very swollen. Very swollen. 2 of the 5 has had the vents covers blown off. Oddly enough all of the eight cells are holding a charge.
I read that some of the swelling can be reduced by applying pressure of the sides. If I could save them great. If not it’s just lessons learned

What voltage did you charge to?

 

[Dunndeal]

I was charging 6 lifepo4 90 ah @ 21.2 volts 3.5 volts per average without a BMS. What about the swelling of the cells

 

[Just John]

I was charging 6 lifepo4 90 ah @ 21.2 volts 3.5 volts per average without a BMS. What about the swelling of the cells

I would throw away or recycle any that have had the vents blown, that liquid is nothing you want to be around (I think chemically it is related to Teflon, I just know it is a hydrocarbon I had never heard of). I have no experience with de-bloating, so hopefully someone else can supply some knowledge.

 

[BiduleOhm]

They're far too bloated to be recovered sadly. It's actually impressive how round they got ?

without a BMS

Here's your problem.

 

[fafrd]

I was charging 6 lifepo4 90 ah @ 21.2 volts 3.5 volts per average without a BMS. What about the swelling of the cells

Yeah, so one or two cells went over 4.1V while the others were still sitting around 3.2V...

Never charge cells in series without a BMS (or at least top-balancing them first). Charging in parallel to 3.65 Volts is much, much safer (with no BMS)...

 

[Bob B]

I am amazed every time I see one of these posts ..... but glad you documented it. Maybe others will see it an learn from your experience.

I would modify your statement that ..... almost everyone destroys their first set of batteries .... to read that almost everyone who ignores the warning to never charge the pack in series without a BMS .... ends up destroying their cells.

 

[MisterSandals]

It's actually impressive how round they got ?

That might be a new record! We need a "hall of fame" location for impressive feats like this.

The recent 48v wrench short was another with impressive results.

 

[BiduleOhm]

Already posted it to this thread: https://diysolarforum.com/threads/afa-our-failures-forum.17306/ ?

 

[SoundinSpirit]

Ditto others.... Thank you for sharing your whoops! Sorry for your loss though...

 

[Swamplizard]

been there - just did a version of that LOL

 

[Dunndeal]

Any one got 2 90ah lifepo4 they’d like to sell

 

[OnTheRoadAgain]

This makes me sad to read this (again)

This is probably one of the few reasons I still can't completely let go of good old Flooded batteries.
Inferior in capacity....inferior in weight....but.......
They're like tanks compared to Lithium batteries, tough as rocks. Am I wrong?

A flooded battery couldn't care less if you overcharge it by a few volts (forget millivolts)...or sit in -10 degree weather overnight.

If I mess up my first LiFePO4 batteries I'm done. SLA Gell flooded for life, for me.
If that happens I'll have a new Overkill 4s BMS for sale dirt cheap.

Now, let me go back and read all the procedures for liFePO4's AGAIN

 

[toms]

This is probably one of the few reasons I still can't completely let go of good old Flooded batteries.
Inferior in capacity....inferior in weight....but.......
They're like tanks compared to Lithium batteries, tough as rocks. Am I wrong?

I bet there has been more flooded lead acid cells destroyed by sulphation than LiFePO4 cells by overcharging.

I have a set of LiFePO4 cells that have been completely untouched (i have since cleared the dust!) for over eight years and have delivered around 15kwh daily over that period. Never seen flooded lead acids able to do that.

 

[Diysolar123]

Never charge cells in series without a BMS (or at least top-balancing them first). Charging in parallel to 3.65 Volts is much, much safer (with no BMS)...

probably happens a lot to folks that do not understand how series battery charging works; somehow this needs to be printed in much bolder language and "sticky" posted to the top of the faq...with the words "never means never"...

 

[Zwy]

Any one got 2 90ah lifepo4 they’d like to sell

I think I'd start over with all new cells, I'd use 4 of remaining cells to build a 12v battery after capacity testing for the best ones.

 

[Just John]

I think I'd start over with all new cells, I'd use 4 of remaining cells to build a 12v battery after capacity testing for the best ones.

I would agree with you, but of course the original poster might have financial constraints. I am about to order some of the 105AH cells from Amy to be able to build some packs that weigh less for my daughters. For genuine straight from the factory grade A cells, they are reasonably priced.

 

[Zwy]

I would agree with you, but of course the original poster might have financial constraints. I am about to order some of the 105AH cells from Amy to be able to build some packs that weigh less for my daughters. For genuine straight from the factory grade A cells, they are reasonably priced.

I asked her the other day about 105Ah to build some trolling batteries for my boat but said they were out of stock. I'm not sure which direction I go now, still looking. I'm starting to wonder if companies like SOK and Big Battery aren't locking up supply of commercial grade cells in order to meet demand plus limit the ability of DIY'ers to buy cells to build their own. The market is exploding right now.

 

[Just John]

I asked her the other day about 105Ah to build some trolling batteries for my boat but said they were out of stock. I'm not sure which direction I go now, still looking. I'm starting to wonder if companies like SOK and Big Battery aren't locking up supply of commercial grade cells in order to meet demand plus limit the ability of DIY'ers to buy cells to build their own. The market is exploding right now.

I'm just going to wait until she has them in stock. Texas is probably playing a big part in increasing demand.

 

[Zwy]

I'm just going to wait until she has them in stock. Texas is probably playing a big part in increasing demand.

She has the 105Ah in stock now, the 120Ah is out of stock.