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Avoid AliExpress "LiitokalaVariCoreFlagship Store" from "$433 280Ah LiFePO4 Cells Tested: Cheaper than lead acid!" video

Bulging cells are a different matter. They bulge when the electrolyte boils. That is what the vent caps are for, to burst and prevent the aluminum cell body from exploding.

I have no experience with bulging cells, but it means that the cell was overcharged or over discharged.

I think OP has "slightly" bulging cells that pull full capacity. So, I am just wondering if there are real safety risks of using such cells?
 
Twice as much may be an exaggeration, but I'd be happy to pay more if I could go into a store and buy a few cells, and if any had the sides bulging to be able to say "No thanks, that one's defective", or if they don't meet the specs, return them easily.
As it stands we have to wait months for an order from China to arrive, only to find that the grade 'A', brand new cells are anything but new.
Just look at the postings to see how many times that has happened.
I mean. It costs nearly twice as much to buy the Chinese cells from an American importer. Not sure why you'd think it would be less than that if we made them here.
 
Yeah that happens with some of these sometimes. Just have to return them.
Common man, have you ever tried to return LIFEPO4 damage batteries that are defective. USPS won't accept them and UPS will charge you more than they are worth.

I would be curious, HAS ANYONE EVER successfully shipped back batteries and gotten a refund?
 
Bulging cells are a different matter. They bulge when the electrolyte boils. That is what the vent caps are for, to burst and prevent the aluminum cell body from exploding.

I have no experience with bulging cells, but it means that the cell was overcharged or over discharged.
But there's a huge difference between 'bloat' and 'not flat', right?

(edit)
They all bulge "slightly" when full.

Ah, answered. :)
 
But there's a huge difference between 'bloat' and 'not flat', right?

(edit)


Ah, answered. :)
Yes, big difference between bloated and full. They do expand when full, but bloating is caused by boiling electrolyte.
 
Just finished two capacity tests on 8x 280ah cells. Cells looked great visually, but the first test after top balance was 230ah. Recharge in series through BMS until high voltage disconnect, retest, 229ah. That's a consistent result, calling it good. Opened dispute immediately, seller is giving me the run around about capacity, declining to accept the dispute. Going to have to take this up with my CC company.

I'm expecting I just lost this roll of the dice, and to wind up keeping the cells with no refund. Anything better than that will be a bonus.

I already have a set of 8 cells coming in from a group buy here on the forum, and will likely purchase another set of 8 from the group buy, and resell these. They're still ~230ah cells, just won't allow my system to meet spec.

Yes, definitely avoid this seller.
 
Just finished two capacity tests on 8x 280ah cells. Cells looked great visually, but the first test after top balance was 230ah. Recharge in series through BMS until high voltage disconnect, retest, 229ah. That's a consistent result, calling it good. Opened dispute immediately, seller is giving me the run around about capacity, declining to accept the dispute. Going to have to take this up with my CC company.

I'm expecting I just lost this roll of the dice, and to wind up keeping the cells with no refund. Anything better than that will be a bonus.

I already have a set of 8 cells coming in from a group buy here on the forum, and will likely purchase another set of 8 from the group buy, and resell these. They're still ~230ah cells, just won't allow my system to meet spec.

Yes, definitely avoid this seller.
I am also currently getting the run around from them. Not only were my cells lower capacity but most of them had crooked threads and they are refusing to accept dispute and offering $0 in return. Waiting for alixpress to step in and see what happens as the batteries were also delivered beyond the 75 day guarantee. Still useable but under spec for me as well.
 
Just finished two capacity tests on 8x 280ah cells. Cells looked great visually, but the first test after top balance was 230ah. Recharge in series through BMS until high voltage disconnect, retest, 229ah. That's a consistent result, calling it good. Opened dispute immediately, seller is giving me the run around about capacity, declining to accept the dispute. Going to have to take this up with my CC company.

I'm expecting I just lost this roll of the dice, and to wind up keeping the cells with no refund. Anything better than that will be a bonus.

I already have a set of 8 cells coming in from a group buy here on the forum, and will likely purchase another set of 8 from the group buy, and resell these. They're still ~230ah cells, just won't allow my system to meet spec.

Yes, definitely avoid this seller.
Where are you located? Can we see the pictures of the cells? Thanks.
 
I ordered 12 280Ah cells from VariCore (Will's link). Having similar experience as others. Tested 10 of 12 cells: 238.9, 237.1, 239.6, 242.9, 237.7, 239.7, 247.2, 240.1, 239.9, 238.4.
Opened a dispute.
Provided testing conditions and time lapse video, pics, and plots of the capacity testing. They promptly rejected stating "The buyer is requested to provide clear test video and picture data. The buyer can not see the displayed data on the picture and cannot prove whether the battery test is completed. The battery test is completed and the cut-off voltage is 2.5V. The battery is tested before sending, and the seller refuses dispute".

In the videos/time lapse, I included the start and stop voltage (within the video frame) measured with a Fluke multimeter.
They attached a blurry video (screen capture attached) displaying supposed testing of these cells at ~304Ah - comical.
I've also attached the capacity test plot of one cell
Would strongly advise not to order from this vendor.
 

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I ordered 12 280Ah cells from VariCore (Will's link). Having similar experience as others. Tested 10 of 12 cells: 238.9, 237.1, 239.6, 242.9, 237.7, 239.7, 247.2, 240.1, 239.9, 238.4.
Opened a dispute.
Provided testing conditions and time lapse video, pics, and plots of the capacity testing. They promptly rejected stating "The buyer is requested to provide clear test video and picture data. The buyer can not see the displayed data on the picture and cannot prove whether the battery test is completed. The battery test is completed and the cut-off voltage is 2.5V. The battery is tested before sending, and the seller refuses dispute".

In the videos/time lapse, I included the start and stop voltage (within the video frame) measured with a Fluke multimeter.
They attached a blurry video (screen capture attached) displaying supposed testing of these cells at ~304Ah - comical.
I've also attached the capacity test plot of one cell
Would strongly advise not to order from this vendor.
They replied with almost the exactly the same to me. What was the end result of your dispute?
Im just rejected their offer of 0 and am waiting to hear from AliExpress.
 
I ordered 12 280Ah cells from VariCore (Will's link). Having similar experience as others. Tested 10 of 12 cells: 238.9, 237.1, 239.6, 242.9, 237.7, 239.7, 247.2, 240.1, 239.9, 238.4.
Opened a dispute.
Provided testing conditions and time lapse video, pics, and plots of the capacity testing. They promptly rejected stating "The buyer is requested to provide clear test video and picture data. The buyer can not see the displayed data on the picture and cannot prove whether the battery test is completed. The battery test is completed and the cut-off voltage is 2.5V. The battery is tested before sending, and the seller refuses dispute".

In the videos/time lapse, I included the start and stop voltage (within the video frame) measured with a Fluke multimeter.
They attached a blurry video (screen capture attached) displaying supposed testing of these cells at ~304Ah - comical.
I've also attached the capacity test plot of one cell
Would strongly advise not to order from this vendor.
Aye, that's the standard reply from them. Let AliExpress step in, they'll see the video, you probably won't get everything accepted at the first attempt.

Additionally, peel back the black cover and try to check the QR code, could be there's some left over text with the real capacity, I found text saying 704Wh (220Ah).

I finished the dispute, got half the money back (unfortunately, I did not pay by credit card, because of reasons).

Also: do not forget to leave a review for the store/product at AliExpress.
 
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BTW a Gentle Reminder Folks. BLOATED & PUFFED UP is obviously a bad thing as it is a sign that something is wrong.. Overcharged or whatever.

BUT DO UNDERSTAND The Blue Wrapped Cells are Aluminium and quite thin actually, just a tad thicker than a Pop Can, they are NEVER perfectly flat/square and they DO expand & Contract with charge & discharge and the Ambient Temperatures also affect that expansion & contraction.

Check out one of Will Latest Videos and pay attention to when he is charging those cells up, he notes the amount of expansion and then the contraction.... ALSO NOTE, that depending on the amperage being pushed into the battery pack, the higher the amperage the higher the expansion potentials. It heats up the chemistry more resulting in more expansion.
 
BTW a Gentle Reminder Folks. BLOATED & PUFFED UP is obviously a bad thing as it is a sign that something is wrong.. Overcharged or whatever.

BUT DO UNDERSTAND The Blue Wrapped Cells are Aluminium and quite thin actually, just a tad thicker than a Pop Can, they are NEVER perfectly flat/square and they DO expand & Contract with charge & discharge and the Ambient Temperatures also affect that expansion & contraction.

Check out one of Will Latest Videos and pay attention to when he is charging those cells up, he notes the amount of expansion and then the contraction.... ALSO NOTE, that depending on the amperage being pushed into the battery pack, the higher the amperage the higher the expansion potentials. It heats up the chemistry more resulting in more expansion.
Was actually reassuring to see that Will just put the cells in a pack anyway. ;)
 
So they are 230Ah REPT cells being sold as 280Ah like in this thread: https://diysolarforum.com/threads/c...est-not-even-near-rated-capacity.26361/page-2). I hope you do get the money back.
I may be interested in buy them (4) for my non critical project but I do not know how difficult and the cost will be to ship these batteries, I am in SF bay area.

You bet, after everything is done with AliExpress, and providing we can figure out a safe, legal way to ship them. Send me a PM.
 
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