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How to tell if EVE cells are A or B, and does it really matter?

apctjb said:
Makes sense.

However in my case I purchased EVE non automotive (B) cells produced in April of this year on the same day, assembly line and they tested to +280AH and paid half the cost of automotive grade cells (which I could not get in the time frame I needed them) If 1500 full discharge cycles is all I get I will be disappointed but that's about 8 years in my application and by then I expect battery technology to have improved...
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That’s what people were saying 11 years ago when i installed my LiFePO4 bank.
 
jimjoe said:
Not sure from your description
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So I don't OT this discussion
 
Bud Martin said:
I believe this place sells Grade A EVE cells since it has EVE terminals on them, I would think EVE will not put on their terminals on failed QC cells.
Some members here had bought some.
www.18650batterystore.com

EVE LF280K V3 Grade A Cells - 3.2V LiFePO4 280Ah Battery

Brand new Grade A EVE LF280K LiFePO4 cells with 280Ah capacity. 10+ years design life, 6,000 cycles. Get unmatched power and performance for your energy storage needs.
www.18650batterystore.com www.18650batterystore.com
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They do seem to be grade A EVE cells and I am an expert in identifying the differences. They have photos of taking delivery from EVE and the wooden boxes that EVE ships them in sometimes. So yes they are Grade A.
 
Alkaline said:
I love this forum, every dreams about grade A but always buys grade B and just pretends they have grade A?
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Spot On. The number of arguments I have had with grade B owners. Even most of the Youtubers didn't know there was a difference and I'm not even sure if they even still know it. No naming anyone in particular, but its been a hell of a time tying to get people to understand what they are actually buying is Grade B.
 
some-random-guy said:
Spot On. The number of arguments I have had with grade B owners. Even most of the Youtubers didn't know there was a difference and I'm not even sure if they even still know it. No naming anyone in particular, but its been a hell of a time tying to get people to understand what they are actually buying is Grade B.
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Most are actually buying FAILED 'Automotive Grade' LiFePO4 prysmatic cells.
Grade A and Grade B terminology is a fantacy of the chinese aftermarket (Gray Market) battery reseller.
These battery resellers can bless the cells they sell with either term, because there is no industrial standard for those two terms.
Grade 'A' and Grade 'B' are strictly marketing terms.
 
Just thought I'd add a vendor's take on this for anyone that's interested.

I think the automotive thing is a marketing ploy personally, peddled by Docan but has now become something that everyone qoutes.

There's no A+, A-. There's just A and B.

We order direct from EVE, and when asked they said:

Grade B are usually cells that do not meet the specification sheet in some way.

We don't know the reason, its different with each cell. It could be a higher internal resistance, lower capacity or expected low cycle life or just general damage. Unfortunately the latter, we won't find out for another 10 years.

We send our Grade B for testing before we purchase them, we capacity test and internal resistance check. We send the bad capacity ones back, and just purchased cells that we like the capacity of. Unfortunately we have to sort through them, and this costs money. We have to pay per Ah on capacity checks plus shipping to and from these capacity factories.

The Grade B stamped on the QR code. This is easily removed with a laser, and reprinted. We've seen video evidence of vendors doing this. So take it with a pinch of salt. If anything, I'd recommend looking for the B, atleast you know the vendor isn't trying to hide anything.

If anyone has any questions for eve, if be happy to forward them across.

Thanks!
 
If anyone has any questions for eve, I would be happy to forward them across.
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Seems like the A & B creates confusion and poor marketing. Curious to ask EVE why they simply don't mark each cell with tested capacity and test standard the cell passed and then bin the cells and price them accordingly. This could be embedded in the QR code. Let customers decide what capacity/price point/test standard works best for their application.
 
Ben@Fogstar said:
Just thought I'd add a vendor's take on this for anyone that's interested.

I think the automotive thing is a marketing ploy personally, peddled by Docan but has now become something that everyone qoutes.

There's no A+, A-. There's just A and B.

We order direct from EVE, and when asked they said:

Grade B are usually cells that do not meet the specification sheet in some way.

We don't know the reason, its different with each cell. It could be a higher internal resistance, lower capacity or expected low cycle life or just general damage. Unfortunately the latter, we won't find out for another 10 years.

We send our Grade B for testing before we purchase them, we capacity test and internal resistance check. We send the bad capacity ones back, and just purchased cells that we like the capacity of. Unfortunately we have to sort through them, and this costs money. We have to pay per Ah on capacity checks plus shipping to and from these capacity factories.

The Grade B stamped on the QR code. This is easily removed with a laser, and reprinted. We've seen video evidence of vendors doing this. So take it with a pinch of salt. If anything, I'd recommend looking for the B, atleast you know the vendor isn't trying to hide anything.

If anyone has any questions for eve, I would be happy to forward them across.

Example of one our capacity tests of grade B attached. Anything below 280 is rejected and sent back. Our Grade A are all a minimum 291Ah.
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have you actually done your own tests to verify what EVE is claiming, I took have 280K that came with the spreadsheet, 10AH lower than what was listed on the sheet. If said 288 on the test report I got 278 on my ZKE.

In fact many people have tested the 280K cells with test report they are all below the rating, and very few are actually even meeting 280AH.
 
Alkaline said:
have you actually done your own tests to verify what EVE is claiming, I took have 280K that came with the spreadsheet, 10AH lower than what was listed on the sheet. If said 288 on the test report I got 278 on my ZKE.

In fact many people have tested the 280K cells with test report they are all below the rating, and very few are actually even meeting 280AH.
Click to expand...

There's actually two versions of the grade A you can request. One that will lose capacity slightly after being shipped , and one that will retain most of its capacity. The former being a little cheaper.
 
Ben@Fogstar said:
There's actually two versions of the grade A you can request. One that will lose capacity slightly after being shipped , and one that will retain most of its capacity. The former being a little cheaper.
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There's also a 1mm difference between the two. Apologies for self reply, was an accident :(
 
What do you mean 2 versions of grade A? There is only versiont hat comes with the manufacturer test report.

Have you actually tested your own grade A with manufacturer test report and compared to the manufacturer claims?

Do you have a ZKE-40 tester can you post your results for the LF280K and compare your results to what is listed on the manufacturer spreadsheet.

Thanks
 
Alkaline said:
What do you mean 2 versions of grade A? There is only versiont hat comes with the manufacturer test report.

Have you actually tested your own grade A with manufacturer test report and compared to the manufacturer claims?

Do you have a ZKE-40 tester can you post your results for the LF280K and compare your results to what is listed on the manufacturer spreadsheet.

Thanks
Click to expand...
Yes, I mean There's two versions of the exact same product. With a 1mm difference.
 
RandyP said:
Most are actually buying FAILED 'Automotive Grade' LiFePO4 prysmatic cells.
Grade A and Grade B terminology is a fantacy of the chinese aftermarket (Gray Market) battery reseller.
These battery resellers can bless the cells they sell with either term, because there is no industrial standard for those two terms.
Grade 'A' and Grade 'B' are strictly marketing terms.
Click to expand...
I agree with this but many sellers have the ability to grade thier products based upon critera they can judge such as capacity, where they bought them and how long theyve been sitting and physical condition (bloated etc) so thier grading system may or may not have SOME relevance... For example I can buy energizer AA batteries at CVS and pay $4 for a 2 pack with an epiration dat of 2028.... or I can buy the same 2 pack at the dollar store for $1.25 with an expiration date of 2024.. They are both new and put out the correct voltage but not in the same condition even though the manufacturer did not grade them differently. (other than an expiration date)
 
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