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New EVE 280ah gaps in cells HELP!!!!

KD7MJK

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Jan 11, 2021
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Hello and thanks in advance for the help!!!

I have just received my first box of 4 EVE 280ah cells from Basen, and on unboxing and inspection I have found the cells are unable to sit flat against each other because of what I believe to be swelling. I am attaching 2 pictures and would love to hear anyone's thoughts... From video Will posted on Jan 8, in the first minute, alarm bells are going off in my head. Let me know what you think... Please!!!
 

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Hello and thanks in advance for the help!!!

I have just received my first box of 4 EVE 280ah cells from Basen, and on unboxing and inspection I have found the cells are unable to sit flat against each other because of what I believe to be swelling. I am attaching 2 pictures and would love to hear anyone's thoughts... From video Will posted on Jan 8, in the first minute, alarm bells are going off in my head. Let me know what you think... Please!!!
Swelling is normal. Read the threads on making a 300kgf clamping fixture.

Lifetime with no fixture is 2500 cycles. Clamping the cells with the proper force will extend lifetime to 3500 cycles.

If you discharge your cells they will flatten and if you continue all the way to empty, they will actually become slightly concave (sunken).

What testing are you planning to do to assure your cells are performing as expected (capacity test, etc...)?
 
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Swelling is normal. Read the threads on making a 300kgf clamping fixture.

Lifetime with no fixture is 2500 cycles. Clamping the cells with the proper force will extend lifetime to 3500 cycles.

If you discharge your cells they will flatten and if you continue all the way to empty, they will actually become slightly concave (sunken).

What testing are you planning to do to assure your cells are performing as expected (capacity test, etc...)?
I have one of those automated DL24 testers that I was going to use, when I was going to keep them, but I lost my job in the mean time... To complicate the matter, I enrolled in a business class through unemployment and thought that importing LiFePo4 batteries for sale (outside of this circle) would be something to try. That said, I was going to sell this set on CL, or FB or Ebay to see how viable it is.
However within the first minute of this video:
$433 280Ah LiFePO4 Cells Tested: Cheaper than lead acid!

I find Will's cells and my cells new out of box do not have the same characteristics...

But that is okay?
 
I have one of those automated DL24 testers that I was going to use, when I was going to keep them, but I lost my job in the mean time... To complicate the matter, I enrolled in a business class through unemployment and thought that importing LiFePo4 batteries for sale (outside of this circle) would be something to try. That said, I was going to sell this set on CL, or FB or Ebay to see how viable it is.
However within the first minute of this video:
$433 280Ah LiFePO4 Cells Tested: Cheaper than lead acid!

I find Will's cells and my cells new out of box do not have the same characteristics...

But that is okay?
First, I would suggest you read EVEs datasheet for those cells (the latest one, Dec 2019).

Second, I would suggest you place all of your cells side-by-side and top-balance them with parallel busbars.

And then third, I’d suggest you settle on some form of clamping/retention before charging your cells. Some use reinforced tape, some use long hose clamps, some use threaded rod with two endplates.

I started charging up individual cells to 3.65V without clamping and saw swelling that concerned me, same as you. I built a simple clamping fixture with 2 pieces of 3/4” x 12 wood and 4 1/4” screws and now I have no concerns.

There are so many variables that impact how cells look ‘new’ out of the box I’d suggest it is meaningless to attempt a comparison based on a video.

Look at EVE’s datasheet, see how your cells measure up.

There is quite a bit of expertise here on the forum regarding EVE’s guidelines for a 300kgf clamping fixture and how to achieve that for various size batteries.

It’s hard for me to imagine how you are going to sell these cells without characterizing Ah capacity first...
 
Those cells Will tested were actually lishen 272’s, not eve cells. I think others have reported that the eve cells don’t stack flat, so I wouldn’t be too concerned
 
Those cells Will tested were actually lishen 272’s, not eve cells. I think others have reported that the eve cells don’t stack flat, so I wouldn’t be too concerned
yea Will is still been rip off the picture was of a eve cell :cool: he was happy so why bother him.
bought the same cells 4* at basen mine looked also the same still pulling 280 ah no problem 0.01 v difference after top balance also no problem
this week, after 60 days of waiting i will get 8 lishen 272 ah from Dongguan Lightning lets see how those are looking and doing i will post it
 
yea Will is still been rip off the picture was of a eve cell :cool: he was happy so why bother him.
Will asked in another thread who the manufacturer is. They are Lishen cells. I would have been happy with that test too since Lishen's are rated at 272ah's. :)
 
Hello and thanks in advance for the help!!!

I have just received my first box of 4 EVE 280ah cells from Basen, and on unboxing and inspection I have found the cells are unable to sit flat against each other because of what I believe to be swelling. I am attaching 2 pictures and would love to hear anyone's thoughts... From video Will posted on Jan 8, in the first minute, alarm bells are going off in my head. Let me know what you think... Please!!!
As has been stated the cells Will tested are Lishen 272ah cells. They are not EVE cells. Many of us have received EVE cells much like the photo you posted. They should be fine. Take a look at this thread.
 
I did get my cells looking like this. When I lifted the first cell I felt this is not ok. They are wery concave...on all sides. Only 1 of 8 is ok. EVE 280 from XUBA. This look ok for you? Did buy grade A cells.
 

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OK a touch of clarity.
The aluminium is SOFT like a pop can and you can squeeze the cells with your fingers & feel it.
Shake the cell around and you will hear a little slushing inside. normal.
They expand & contract relative to Temp & State of charge. High SOC they expand, Low SOC they contract. Hi Temp they expand, Low Temp they contract. NORMAL. That can be as much as 2mm for 250-300AH cells.

Weigh each cell in GRAMS and compare them, you will likely find a slight variance in weight between the concave cells & the fatter" cells.
That is what you get with Bulk Commodity cells supplied by Battery Cell brokers to vendors.

Even CALB's, SinoPoly & Winstons in their ABS casings will do this to an extent. These are NOT "harder" Cylindrical cells which resist such.
 
OK a touch of clarity.
The aluminium is SOFT like a pop can and you can squeeze the cells with your fingers & feel it.
Shake the cell around and you will hear a little slushing inside. normal.
They expand & contract relative to Temp & State of charge. High SOC they expand, Low SOC they contract. Hi Temp they expand, Low Temp they contract. NORMAL. That can be as much as 2mm for 250-300AH cells.

Weigh each cell in GRAMS and compare them, you will likely find a slight variance in weight between the concave cells & the fatter" cells.
That is what you get with Bulk Commodity cells supplied by Battery Cell brokers to vendors.

Even CALB's, SinoPoly & Winstons in their ABS casings will do this to an extent. These are NOT "harder" Cylindrical cells which resist such.
So if they look like sh*t, why say that they are grade A? NOT buying from Xuba again.
 
So if they look like sh*t, why say that they are grade A? NOT buying from Xuba again.
Could you post a photo of your two worst cells by placing them face to face and then take a photo from the top and the edge side? Many of us have received undulated cells but they work perfectly fine. Take a look at this thread and compare to what you received.

It's already been determined no one is selling grade A cells except the manufacturer. If buying directly from the manufacturer they would cost at least 2.5X more than what we paid. However there are things that are not unacceptable such as the suppliers sending out dented cells or cells damaged in shipping.

I understand your frustration with the supplier claiming they are grade A. Most suppliers make that claim. In my view the cells are grade A- or B+ at best. But I am not complaining for the price I paid and I too received undulated cells advertised as grade A.
 
Could you post a photo of your two worst cells by placing them face to face and then take a photo from the top and the edge side? Many of us have received undulated cells but they work perfectly fine. Take a look at this thread and compare to what you received.

It's already been determined no one is selling grade A cells except the manufacturer. If buying directly from the manufacturer they would cost at least 2.5X more than what we paid. However there are things that are not unacceptable such as the suppliers sending out dented cells or cells damaged in shipping.

I understand your frustration with the supplier claiming they are grade A. Most suppliers make that claim. In my view the cells are grade A- or B+ at best. But I am not complaining for the price I paid and I too received undulated cells advertised as grade A.
I already did repack them for transport. photos are in erlier post. Youtuber off grid garage had some minor colorspots on his and he was compesated whit new ones, and that was nothing compared to mine. However, live and learn. Just my experiense.
 
A vendor buying from a Broker is buying in lots of 500-1000 cells at a time in batches. The broker tells them they are Grade-A or B or whatever, the Vendor does not necessarily KNOW the difference, they just pass on what they are told. Some Vendors (few) deal direct with Manufacturers because they have their own MOQ, for example for CATL it is an "absolute minimum of 1000 pcs". The same applies to EVE by the way.

BUT when a Vendor goes direct, the cost will be somewhat higher BUT they can also get batch reports from testing. For an additional fee (to vendor) they can be "Batched" during production tests which raise's the bar and the cells are much more closely matched as a result. This is still not Fully Matched / Batched & Binned which is a much more intense process that easily adds 50% on top of the cell cost ($50 cell becomes $75) which many don't want to pay for.

FYI-BTW: The vendor I recommend to folks now goes Direct To Factory, NO MORE Broker Nonsense ! Cell prices are a tad higher but you get what you pay for. A hint is in my Signature IF Curious as to WHO if you do not already know.
 
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