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

DSmartLife

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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.
 
I really wish there was a SECOND standard aside from just the EV automotive standard for cells.
We really need like:
  • EV/Automotive grade
  • Solar grade
  • Grade B (good luck!)
 
This seems to be a rumor, but it seems that you have a misunderstanding. For battery factories, EV batteries are their main business, and the batteries that are suitable for cars are classified as A, and those that are not suitable for cars are classified as B or below, which is a fact. And for us, the best battery we can buy is the Grade B battery from the battery factory, for the simple reason that we are just individual consumers, and we are not eligible to buy batteries suitable for EVs.
A Grade B battery doesn't mean bad performance. Performance-wise, most Grade B isn't much different from Grade A, and the more reason they're classified as Grade B is "dimensions that don't fit the EV's specs." If you are interested, you can check what Grade A batteries are.
You may ask, why can't we buy EV batteries (A)? Bro, we are just ordinary. Buying a batch of batteries costs a few thousand dollars at most. EV companies spend hundreds of millions of dollars to buy batteries every year. Can this be the same? The rich will always have the best in the world.
 
And for us, the best battery we can buy is the Grade B battery from the battery factory, for the simple reason that we are just individual consumers, and we are not eligible to buy batteries suitable for EVs.
This is categorically false. You can buy whatever grade battery from the factory you want, if you want to pay more for the EV spec batteries that is absolutely an option available to you.
 
If the battery pulls capacity what’s the concern? If you are designing a system that’s dependent on pulling 1c-2c consistently, IMO you need to redesign your system
 
If the battery pulls capacity what’s the concern? If you are designing a system that’s dependent on pulling 1c-2c consistently, IMO you need to redesign your system
Yeah not much of a concern if it pulls full capacity. However the cell quality can be very different compared to Automotive grade tested cells. It just depends on luck also. And the cells we get are always 1-3yrs old (may not be used but not new stock). So it is a gamble, but for Solar DIY projects with low C rates, it is probably fine.

Real grade A cells from EVE will accompany with factory test reports as given below and will be fully matched. The report has 3 IR values and Tested Capacity.
1653353467190.png

You can get these Automotive Grade A Cells with test report from EVE directly or SunFunKits.

I was interested if EVE has started marking their Cells that fail the grade A test because now it will be easy for us to identify. According to one of my supplier they have started marking recently, but others have not said anything. Have to just wait and see.

If EVE really does it then it will be very interesting for the market because, suppliers cannot simply tell their cells to be Grade A, like they do all the time now if the QR is intact.
 
those that are not suitable for cars are classified as B or below, which is a fact. And for us, the best battery we can buy is the Grade B battery from the battery factory, for the simple reason that we are just individual consumers, and we are not eligible to buy batteries suitable for EVs.
That has always been my assumption. I was certain we were getting cells that did not meet the automotive manufacturers standards. I am still happy with my pack and really do not care what grade they are. $125 per kWh was a great value and has already saveed me upwards of $25 per month and possibly more as my NEM benefits get eroded.
Years ago for an EV conversion project I bought some Winston's at $350 per kWh and I am also pleased with the value I got with my LF280s even if they do not last as long as the Winston's might have lasted.
 
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EV or Automotive cells will last nearly twice as long as rejected cells that become classified as Telecom cells.
Here is a graph on it. This is at 1C Discharge and Charge.
AutomotiveCell.jpg
Batteries like the ones in the EG4 are clearly labeled as Telecom cells by the manufacturer gangfeng Lithium
http://www.ganfenglithium.com/pro3_detail_en/id/173.html
This Data comes from their own UL Application.

As I said it's no big deal if you get half the life for half the price. It might even be a bonus as who knows what new cells will be capable of in 5 years.
 
This is categorically false. You can buy whatever grade battery from the factory you want, if you want to pay more for the EV spec batteries that is absolutely an option available to you.
Sorry! I'm missing one premise: most DIY batteries. Some factories with few EV battery companies can still create their best batteries for you, like Winston. But now the most cutting-edge technology of LiFePO4 batteries exists in battery factories capable of manufacturing EV batteries. It is almost impossible for you to buy EV batteries from them. If you pay more attention to the news, you will know that the global EV industry is in short supply. , either the chip or the battery. The odds that we as individuals will be able to buy EV batteries are simply too low. It's not a question of how much money you give, it's a question of whether the battery factory is willing to give it to you.
 
That has always been my assumption. I was certain we were getting cells that did not meet the automotive manufacturers standards. I am still happy with my pack and really do not care what grade they are. $125 per kWh was a great value and has already saveed me upwards of $25 per month and possibly more as my NEM benefits get eroded.


My point is the same as yours, the so-called grading really doesn't make much sense, and performance is everything.

As far as I know, both Tesla and BMW have experience communicating with EVE Energy...Although I don't know if they have successfully cooperated, compared with these super companies, we are nothing... Not only the above company, but EVE Energy also has long-term cooperative relationships with many Chinese EV companies.

I think it's pretty good that we can get just a battery that's not the right size (better Grade B battery), it's almost impossible to get a real EV battery. So for the Grade A batteries of many suppliers, I turn a blind eye... After all, the performance is up to the standard, and the inconsistent size is not a big problem.
 
Sorry! I'm missing one premise: most DIY batteries. Some factories with few EV battery companies can still create their best batteries for you, like Winston. But now the most cutting-edge technology of LiFePO4 batteries exists in battery factories capable of manufacturing EV batteries. It is almost impossible for you to buy EV batteries from them. If you pay more attention to the news, you will know that the global EV industry is in short supply. , either the chip or the battery. The odds that we as individuals will be able to buy EV batteries are simply too low. It's not a question of how much money you give, it's a question of whether the battery factory is willing to give it to you.
While it is true that supplies are low right now the battery manufactures have commitments to both the EV makers and the Tier 1 battery pack companies. Almost every supplier will keep distributing to everyone at an equally reduced share so as to keep clients and not alienate them. Also the manufactures make more money per battery selling to the Tier 1 companies because the volume is a lot less and therefore the price is higher. Lastly I think your forgetting that Home Solar is just one of many industries that are buying these Tier 1 cells. You have electric Fork lift companies as well as the Aviation industry and Train industry that use them for various machines and as backup power.

BTW I have no idea why you think the Grading is not a real thing. It is well documented that they have a 30 day testing period on the batteries at which point they are sorted into different categories. We also have refurbished cells which is another huge industry in China. Lots of small companies in China are competing to buy Telecom cells, some buy the best of the EV rejects and some buy the cheapest.
 
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It is well documented that they have a 30 day testing period on the batteries at which point they are sorted into different categories.
I think there may be an initial testing to eliminate wasting 30 days on the ones that do not make that cut, but I can't say where that is documented. Where is your well documented statement documented?
 
While it is true that supplies are low right now the battery manufactures have commitments to both the EV makers and the Tier 1 battery pack companies. Almost every supplier will keep distributing to everyone at an equally reduced share so as to keep clients and not alienate them. Also the manufactures make more money per battery selling to the Tier 1 companies because the volume is a lot less and therefore the price is higher. Lastly I think your forgetting that Home Solar is just one of many industries that are buying these Tier 1 cells. You have electric Fork lift companies as well as the Aviation industry and Train industry that use them for various machines and as backup power.

BTW I have no idea why you think the Grading is not a real thing. It is well documented that they have a 30 day testing period on the batteries at which point they are sorted into different categories. We also have refurbished cells which is another huge industry in China. Lots of small companies in China are competing to buy Telecom cells, some buy the best of the EV rejects and some buy the cheapest.
Because I don't think battery grading is meaningful, it's scary that there is no industry standard for battery grading, and each battery factory has its own grading standard. So I generally only believe in battery performance, battery grading is like 100% juice on a juice drink, I wouldn't believe it.

Of course, this is just my personal opinion, because now almost everyone who sells batteries will label themselves as Grade A, which is difficult to distinguish between true and false.
 
I agree that there is no industry standard. The fact that EVE will begin using B as a prefix is not an industry standard either.
 
I think there may be an initial testing to eliminate wasting 30 days on the ones that do not make that cut, but I can't say where that is documented. Where is your well documented statement documented?
Here is one.
 
Because I don't think battery grading is meaningful, it's scary that there is no industry standard for battery grading, and each battery factory has its own grading standard. So I generally only believe in battery performance, battery grading is like 100% juice on a juice drink, I wouldn't believe it.

Of course, this is just my personal opinion, because now almost everyone who sells batteries will label themselves as Grade A, which is difficult to distinguish between true and false.
I agree everyone in the grey market labels them Grade A, but that's a lot like saying every hotel claims it's 5 Star and then concluding that means no hotel is a 5 Star hotel. I also think your lumping Capacity and Longevity into one. Almost all the cells will have full Capacity but the defects in manufacturing are what shorten the longevity and therefore get them rejected from EV and Tier 1 sales.
 
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I have seen that video before and discounted it as a sales pitch. I agree he says something about 28 days for the formation process Other videos have suggested Panasonic/Tesla can do the formation process in less than ten days. There also have to be some that don't make it past the initial CT scan. Where those end up in the grey market is anybody's guess. He does not say they all make it through the 28 day process. Perhaps there is some binning during that time.
 
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I have seen that video before and discounted it as a sales pitch. I agree he says something about 28 days. Other videos have suggested Panasonic/Tesla can do the formation process in less than ten days. There also have to be some that don't make it past the initial CT scan.
I don't know why you discount it as a sales pitch. He only mentions the word Seplos once as his current employeror and he is not pushing Seplos products or even trying to tell you what to buy or from whom. He states that he has worked for years at different LFP Battery Factories and then explains the process.

I agree that a percentage of cells probably don't get past the X-Ray scans and I am sure some are discarded off the bat because the weight or ESR is just way out of Spec.
 
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Regarding the test standard, yes there may not be a clear international standard, but the Chinese govt has a standard "GB/T 31485-2015" and if the cells are to be used in the automotive industry in China, the cells from any manufacturer should pass this test. The ones we get for DIY or even those telecom grade cells are the ones that fail this test standard.

You can look into any cell spec sheet and find the standard in the test page. e.g.:
1653390669318.png

I think the SFK team has shown more details than Seplos about test and test reporting, grades in their video below:
 
EV or Automotive cells will last nearly twice as long as rejected cells that become classified as Telecom cells.
Here is a graph on it. This is at 1C Discharge and Charge.
View attachment 95597
Batteries like the ones in the EG4 are clearly labeled as Telecom cells by the manufacturer gangfeng Lithium
http://www.ganfenglithium.com/pro3_detail_en/id/173.html
This Data comes from their own UL Application.

As I said it's no big deal if you get half the life for half the price. It might even be a bonus as who knows what new cells will be capable of in 5 years.
I think this just strengthens designing a system with .5c or less demand (.2c is probably more ideal) is not only east but also not that more expensive.
 
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