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EVE identifies Grade B cells using new marking Method [Reposting from General]

Capacity is reduced to 80% name plate
How have you been seeing LiFePO4 fail?

My experience is when they are down below 80% of original SOC, you can no longer use their rated discharge current, and they do “fall off a cliff” in a similar fashion to other lithium chemistry.
80% SOC? Don’t think anyone is talking about SOC, more of 80% nameplate capacity after so many years and cycles.

Maybe an issue on my end understanding your terminology.
 
nameplate capacity ≈ "original SOC"

by fall below 80% original SOC i think this means the tested capacity falls faster after the tests come back with 20% fewer Ampere hours than the first test (which hopefully would be close to nameplate)

at least this is how i was reading.

most of my DIY batteries have only a dozen or fewer cycles on them, so i have a loong way to before having insights from 2000+ full cycles ?
 
Capacity is reduced to 80% name plate

80% SOC? Don’t think anyone is talking about SOC, more of 80% nameplate capacity after so many years and cycles.

Maybe an issue on my end understanding your terminology.
Sorry, meant capacity - when your 100% SOC becomes your original 80% SOC.

I’m curious to hear of the cells that are still useful for a long time after this drop in capacity. The newer cells have better electrolyte than a decade ago, maybe they hang on for longer?
 
I heard they removed the B from the B cells

Who? EVE?

Not surprised, probably couldn't sell any more of there failed cells. I called it (if its true) they would do this no one was buying there failed cells, its because of this you see sellers pushing grade B CATL now. Hell the grade B catl tests quite high in fact.

But once EVE stops marking the cells with B, magically you will see them back in the supply.

I hope this is not true, but EVE seems like the company that would do this.
 
I for one commend them for trying to mark their cells so people could tell what they were.... Damned if you do damned if you dont. I guess everyone wants to be able to choose to plausible deniability that their grade B stuff is grade A
 
I think they would have done a lot better if they would have marked the non automotive grade cells with an "S" or something to indicate "Solar/Storage" grade cells. instead of "B" which weve been conditioned to see as flawed or inferior for our needs. (of course if you are in the camp that believes these do have inferior performance for solar overall than the "B" is still more accurate..)
 
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Looks like Docan is doing this as well now:

304 supposedly made in July 2022:


Another guy with 280K, made in August 2022 (hard to tell but last picture shows around the border a clear relaser area):

So yeah, the manufacturer test report is still the gold standard as far as I"m concerned, Clearly these guys are getting better and better, Pretty sure they will start using a cnc process to level the top level and then laser the cell to where no relasering marks will be visible.
 
The more and more I read and watch on this the more I believe theres no real consistency to any of this and so many variables ..
 
The only sure thing you can get from Grade A is that it will not be BAD. I think the whole it will be better than grade B is beginning to seem like a myth. That being said I have yet to see anyone with Bad, like TRULY bad grade A cells.

I don't think capacity tests are not a good way to determine the difference between grade A or B. Its hard to explain but a "Cell Misbehaving Test" would be something... Hard to quantify though.

This is hard to explain but my Luyuan 8s Pack just worked, stayed in balanced and none of the cells did strange things. Not the case with the Xuba or Basen pack. You just can't show this a cell at a time, when you do there is hardly any difference. I don't know how to explain it ?...But grade A behave different when in a pack then by themselves.
 
The only sure thing you can get from Grade A is that it will not be BAD. I think the whole it will be better than grade B is beginning to seem like a myth. That being said I have yet to see anyone with Bad, like TRULY bad grade A cells.

I don't think capacity tests are not a good way to determine the difference between grade A or B. Its hard to explain but a "Cell Misbehaving Test" would be something... Hard to quantify though.

This is hard to explain but my Luyuan 8s Pack just worked, stayed in balanced and none of the cells did strange things. Not the case with the Xuba or Basen pack. You just can't show this a cell at a time, when you do there is hardly any difference. I don't know how to explain it ?...But grade A behave different when in a pack then by themselves.
Fair enough... I'm having no balance or behavioral issues with my aliexpress pack in the golf cart.... yet
 
Another newer video from yesterday.. Ironically the misbehaving cells here are not the grade b..
 
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lol yup... until He shows evidence for his opinion with long term comparison testing its just an opinion. hes not even compressing them correctly at all there showing his bias regardless. until I see some actual long term testing showing it doesnt effect capacity as well as cycle life I am just as inclined to believe it might.
 
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Yesterday I got a new information from my supplier. I was supposed to order EVE LF230 (230Ah) cells from them. But it seems there has been a change on how EVE is sending out rejected cells (Tested to be lower than Automotive Grade) for auction to the Chinese market (grey). According to the new information EVE has started marking the letter "B" on the QR code of LF230 and LF280K cells that were being auctioned. I have attached the pictures below.

View attachment 95191

View attachment 95192

View attachment 95193

It looks like they have also scratched off the serial number part. However the production date code is still intact, which is good for us. CATL has been scratching off the entire QR codes on their Grade B cells, but I think this is a new step from EVE.

If anyone has got this new info, please share. We need confirmation if this is going to be the standard going forward.

P.S. If EVE is really taking this step, then we will see huge changes in the market, as all of the cells that we get are these rejected cells that are being auctioned off at a much lower price. But all of the sellers claim these cells to be Grade A and are selling at a huge profit margin. However most of these unused cells will pass our capacity test and is still suitable for Solar ESS, so we really cannot complain. We will have to see how they handle this new marking of the reject cells. Note that there are a few legitimate Grade A suppliers like SunFunKits or buying directly from EVE Energy Co. As far as I know, all the other suppliers send us these non-automotive Grade B cells.
Hi
just a question, how do you use those terminals without studs? are you drilling a whole or laser welding studs? thanks
 
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