EVE 280K LiFePO4 Cells from QSO/Shenzhen Qishou Technology

[Nightguest]

Made another Alibaba purchase, this time for LiFePO4 cells from QSO.

Putting the important part first - I've had no problems at all, delivery was super fast, the cells are overachieving, and I am extremely happy.

Photos:
Packaging


The cells - do they bulge or not?
Important: I did NOT buy automotive-grade cells. These are advertised as A grade, and from my experience that tends to mean the best of the cells that either did not make the automotive-grade cut or have been sitting in a warehouse for too long to be used for one. This is not a negative point, and I'm actually really glad that thanks to pressure from what seems to be the DIY solar community, sellers are now distinguishing between B, A, and automotive.

Edit
I am making an edit after reading/replying to some comments as I was not clear, my bad, and sorry. Regardless of the fun conversation below, I do agree with Alkaline that these are not grade A, something that I expected from the start.

Additionally, after wrecking my arm removing glue that must have been developed in hell, by an utter madman, I discovered clear signs that the original QR code was removed and that a new one was added on top. Please see the image below, while I was unable to remove all of the glue (to my eternal shame, I gave up), one can clearly see the difference in the cell and the area where the QR code is. This is indicative of the QR code area having been cleaned (sanded I guess), and then a new code applied on top.



This makes my position rather difficult.
If looked at objectively, we have two sides:

• The cells do perform well when tested for:
  
  • Measured capacity
  • Calculated capacity (watt-hours divided by average voltage from discharge test)
  • Ability to sustain at least 3.2V under various C rates when discharging.
• These cells have had their identification tampered with. As such, one cannot accurately ascertain their origins nor be certain that they would sustain 80% capacity for 6000 cycles.
  
  • To be fair, I cannot prove that QSO tampered with the QR code themselves, however, as the selling party, the responsibility to take care of such matters falls squarely on their lap.

From my perspective, I am going to keep these cells as I did expect this (to an extent), and have come prepared.

However, for the community and anyone looking for a recommendation, I CANNOT recommend this seller as I would have no clue as to what quality cells YOU will receive.

The sad situation is that had QSO been upfront about this, I would be (honestly) overjoyed and would happily recommend them. However, they were not.

Essentially, I am happy with the cells, however, I am frankly disappointed in the seller and unless something changes, cannot in good conscience return to them, nor recommend them.

- Edit over, please do read the rest of this post, and even this thread as it does have some useful information on the cells that I have, how I tested them, and how to identify some of the potential issues that one may face when buying cells.

So, to my cells, some of them sit almost perfectly flush like this:
Important: I added the soft padding on the outside of the cells myself, I just forgot to take a photo of the cells before I put it on. Also, the scratches on the top (the black part) are from me as I was poking at it a bit, while it was extremely hot over here. When they arrived, the top was NOT peeling at all, and there were no signs of any re-layering at all.



While others are like this:


Those 2 photos are of the same cells (just odd lighting, sorry), and are the "worst" of the cells. However, given that THIS is the worst, I have absolutely nothing to complain about as that far exceeds my expectations, and actually think that this is perfect. I can squeeze them together with my hands, without any problem, and that flattens them out completely. So when they go together and get some compression, I'm certain they'll be fine.

How things went and testing:

Buying Experience

• I live in Europe / The Netherlands.
• Contacted Vanessa Shi from QSO over Alibaba, and she was really really helpful.
• Originally, I was looking for EVE 304Ah, however as they don't stock them in their EU warehouse, Vanessa recommended the EVE280Ah or the CATL 304Ah.
• I was quoted 1728 euros for 16x EVE280Ah and 2128 euros for the 16x CATL 302A. Those prices had shipping included, and as they were shipped from their EU warehouse (Poland), there were no additional taxes.
• I went for the EVE280Ah

Delivery Experience

• Paid on the 22nd of August
• Tracking numbers provided on the 23rd of August
• Cells arrived on the 24th.

That's 2 days delivery from the moment I paid, which, for me is a record. Honestly, that threw me off completely as I was expecting a week or something, so they arrived before my larger battery tester arrived.

Testing the cells
This is still WIP, however, I've now had consistent results for 13 out of 16, so I'm happy to write this part up now.
I have two battery testers, the EBC-A20 and EBC-A40L. The A40L arrived a week ago, so for the first 2 weeks, I was testing with just the A20. Now, I'm happily using both.

Basic Info:
15 cells were measured at 3.30V, the remaining (1) cell came in at 3.34V.
Based on how much they charged and discharged, they were approximately 60% charged.

Cell results, this part is interesting, but, thinking about how LiFePO4 cells behave in general, is not surprising.

• Charge voltage: 3.65V
• Discharge voltage: 2.95V

When testing with the EBC-A20,

• Charge current: 5A
  • When charging, the cut-off was set to 1A, I did not have the patience to set it to 0.1A
• Discharge current: 20A

Results: All cells were shown to have 295Ah to 301Ah.

When testing with the EBC-A40L

• Charge current: 40A
  • Current cut off: 1A
• Discharge current: 40A

Results: All cells ranged from 290Ah to 296Ah

Based on the EVE280K specifications, I could go down to 2.5V when charging/discharging so, the fact that I got up to 300Ah when not hitting the actual 0 is excellent.
Spec sheet: https://www.battery-germany.de/wp-c...80K-280Ah-Product-Specification-Version-B.pdf

This is nice (even if accidental) proof that the more gentle one is with their cells, the better they perform.
Right now I wish I saved screenshots of all of the graphs, but the tests take so long that I get over-excited at the results, and after noting the capacity, I swap in the new cell and then entirely forget to save the graph.

So, all in all, I am completely happy and hope that this review helps people here.
If anyone has any further questions or would like some more photos, please do make yourself heard!

 

[Alkaline]

The sellers are LYING to you friend, there are only cells that pass and those that fail. Generally failed cells are called grade B, and the passing are normal cells.

Cells can be built to automotive standard or ess standards there is a different test for both, this myth or ohh if it failed automotive testing its now a grade A storage cell is bunk. Grade A is considered cells that pass certifications to the specification that it was designed to be.

All other grades are nonsense sellers make, gobel does around calling these cells "LSEV" or whatever. Its Not.

I really thought the community was beyond this but looks like we are right back to where we were 2 years ago.

I have a question did you examine your QR code was intact or have a B on it?

 

[Alkaline]

And if you really want to know:

Docan Power bad experience, beware.

Hello! Having read here on this forum a lot of positive feedback about Docan Power decided to buy from them on Alibaba. Ordered 84pcs of Eve LF280K cells from Docan in January. Sales rep was Jenny Wu. Cells were sold as "brand new Grade A". I paid almost USD12K for them, USD141 per cell...

diysolarforum.com

I can assure you, your cells originally looked like this:

EVE identifies Grade B cells using new marking Method

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...

diysolarforum.com

So most probably grade B cells, sanded and re-lasered to look like grade A. But you can verify on your own.

Fore me that white sticker on the side tells me all I need to know, dead give away, grade B cell that was re-lasered as is the MO of all Ali-Sellers except for Luyuan.

 

[Quattrohead]

So most probably grade B cells, sanded and re-lasered to look like grade A. But you can verify on your own.

Did you look at the pictures ?
They are the latest version of the EVE cells and seem to have good looking QR codes..
Honestly, your hatred of all things battery is getting old.

 

[Sam Cho TX]

Doesn't mean what he said is wrong, that little white sticker is used by a lot of grade B sellers. Some grade B sellers leave the B in tact while others will sand and relaser it. The op can remove the black top cover to find out, you should hold your judgment until then.

 

[Anker Luo]

Why don't you find a Chinese person to help you purchase in China?

 

[Nightguest]

The sellers are LYING to you friend, there are only cells that pass and those that fail. Generally failed cells are called grade B, and the passing are normal cells.

Cells can be built to automotive standard or ess standards there is a different test for both, this myth or ohh if it failed automotive testing its now a grade A storage cell is bunk. Grade A is considered cells that pass certifications to the specification that it was designed to be.

All other grades are nonsense sellers make, gobel does around calling these cells "LSEV" or whatever. Its Not.

I really thought the community was beyond this but looks like we are right back to where we were 2 years ago.

I have a question did you examine your QR code was intact or have a B on it?

I did check the QR codes, and I did peel off the top of a few and nothing was scratched off. Here's a peeled-off version of the code.



However, perhaps I was not clear what I meant regarding this part:

Important: I did NOT buy automotive-grade cells. These are advertised as A grade, and from my experience that tends to mean the best of the cells that either did not make the automotive-grade cut or have been sitting in a warehouse for too long to be used for one. This is not a negative point, and I'm actually really glad that thanks to pressure from what seems to be the DIY solar community, sellers are now distinguishing between B, A, and automotive.

What I meant is that I don't buy the grade A/B whatever BS that sellers apply to batteries.
The way that I understand it is that EVE will test the cells and then either pass or fail them for use in the automotive industry. Based on that, it is my understanding that EVE will mark any cells that do not pass the automotive as "B". However, from the EVE "B" grades, you have those that have been used (typically the stuff you get for cheap from Aliexpress), or those that have not been used and are sitting around in a warehouse.

So, I guess technically, these cells, and I'll assume that every non-automotive grade cell from EVE is going to be a "B" grade.

This part is entirely personal, so it may not apply to others, and I welcome anyone explaining why I'm wrong if I am.
What matters to me is the following:

• The tested capacity of the cells.
• When testing the cell, what the discharge graphs look like.
• I've not done this with these cells, but, occasionally I can be pedantic with the cell testing by fully charging them (3.65V), then doing a full 1C discharge on the cell (ok, 1C is overkill, 60A+ is enough), and then monitoring the voltage. What the cell voltage does at this rate will show you how healthy the cell actually is at two points. (I don't have the equipment for that now, I previously borrowed one from a friend)
  • First, if the cell is amazing, the voltage will remain at 3.2V when under a 1C rate. If it's good enough, it'll drop to around 3V, if it's crap, sub 3V.
  • Second, once you disconnect the load, how fast does the voltage go back up to 3.6X V. Good cells will bounce back fast, crap ones will do it slow.

So, in my situation, these cells are totally fine, and still better than what I expected, so I do not feel lied to here.

 

[Quattrohead]

And I guess this was my point, you were happy with the cells and just reported on the facts that you found about them so therefore you didn't need anyone doubting your opinion of them.

 

[Alkaline]

I did check the QR codes, and I did peel off the top of a few and nothing was scratched off. Here's a peeled-off version of the code.

View attachment 168793

if you are going to look then you need to look properly, no can tell with that glue around it, clean it off all the way and then compare to the rest of the cell which you can't see in you picture because you still have it covered with glue.

Look:

https://diysolarforum.com/attachments/20230502_153709-jpg.147572/

So if you just don't want to do it, that is another story. But if you are going to make a claim this company sells grade A then be prepared to be questioned by skeptics who have seen ali sellers pull scam after scam.

Grand B sympathizers can upvotes their hearts out, it won't change this fact.

 

[Alkaline]

use rubbing alcohol and slowly rub away, you can like your cells and that is fine, but at least you will know the truth.

 

[Nightguest]

if you are going to look then you need to look properly, no can tell with that glue around it, clean it off all the way and then compare to the rest of the cell which you can't see in you picture because you still have it covered with glue.

Look:

https://diysolarforum.com/attachments/20230502_153709-jpg.147572/

So if you just don't want to do it, that is another story. But if you are going to make a claim this company sells grade A then be prepared to be questioned by skeptics who have seen ali sellers pull scam after scam.

Grand B sympathizers can upvotes their hearts out, it won't change this fact.

I'm sure that my writing this will be an exercise in futility, however on the off chance that you've genuinely misunderstood me, rather than simply (inexplicitly) disliking something about batteries, then:

• I'm not claiming that these are grade-A cells. In my original post, I was a little unclear, so I clarified it in the last post I wrote that these are, by EVE grading, B. However, B-grade cells come in many shapes and sizes, some will be very good, and others will be very bad.
  • This is why we all test, and why we test using a lot of current, not just 5, 10, 20, 40A, more so.
• If you wish, the QR code that is on these cells comes down to this:
  • The QR code: 04Q-CB-76G58-403JD-2A000-5263

• What I am saying, however, is that what is marketed (by, for example, the sellers on Alibaba) and what is graded by EVE is not the same thing. You very rarely get true grade A from resellers as, based on what I've been told, true grade A is reserved for commercial BESS, and Electric Vehicles (cars and buses). Then there is the whole issue of EVE having multiple factories and each one produces to a different standard, something which I think you were referring to earlier on.
• In my opinion, the general (common) information regarding "Grade A, Grade B" etc. (so what is purchased from resellers) is utter codswallop, as, other than to give one a rough estimate of the potential range/quality of the cell, it serves almost no purpose whatsoever. If one buys raw cells, one must always test them to ensure that what has been purchased and received meets the performance claims of what was promised and sold.
• Some grade B cells are frankly trash to the point that using them with a 1C discharge when in a battery pack, will probably trigger the BMS's low voltage disconnect even if the cell is fully charged; while other times, a grade B cell will be amazingly good and hold voltage between the 3.2v to the 3.3v range when under a 1C load, and for a long time.
• Based on all of the above, it is my belief that an Alibaba EVE "grade A" cell will almost always be an EVE grade B that simply performs very well.
  • This is my own personal thought pattern and I might be wrong, and you're entirely free to disagree.
• One thing that I will thank you for is for reminding me of the purpose of this section, which is to help new people make an educated decision on what to buy and from where; so for that sake, I will edit my original post to make this clearer.
  • Where I disagree with you is the accusation that the sellers are 'scamming' people. These cells were sold to me as storing 280Ah, in reality, they store more, and based on the discharge voltage curve, the watt hours the cells supply likewise exceed the label.
    
• I have to be honest, I do enjoy replying, I mean this all positively as thanks to you I have learned some more as each time you post I go back to my cells, check them out more, reopen curves, contact people to answer questions, etc. So, please don't take any of this as an attack on you, for the most part, I thank you for caring enough to post.

The good news is that very soon most of the above will be moot, as (to my understanding) from June 1, all EVE cells will be directly marked with the letter B if they fail the A grade test. However, it is interesting that they do not outline what the A-grade tests are. That's going to be good for everyone.

 

[Quattrohead]

Some people has been outright lied to and were seriously fucked, so yes we are a little protective.
Seems to be a standard MO of our far eastern friends to start selling good cells and then start slipping the rejects into the pipeline.
But you seem to have taken all precautions and got good cells.

 

[Sam Cho TX]

I did check the QR codes, and I did peel off the top of a few and nothing was scratched off. Here's a peeled-off version of the code.

View attachment 168793

That is a not a useful picture, rest of cell is covered, why aren't you removing the glue so we can see the rest.

You can not compare unless you see the rest. Why even bother peeling cover if that is all you are wanting to show.

I think Alkaline is right, he has been right on many of these situations, I understand he can get under people's skin including mine, however, some of his claims have merit.

 

[Nightguest]

That is a not a useful picture, rest of cell is covered, why aren't you removing the glue so we can see the rest.

You can not compare unless you see the rest. Why even bother peeling cover if that is all you are wanting to show.

I think Alkaline is right, he has been right on many of these situations, I understand he can get under people's skin including mine, however, some of his claims have merit.

Now I'm curious about something cause I may not have the correct info.

My understanding, from the EVE spec sheet, is that the QR codes have to be in a specific location, specifically, exactly where it is in my image. Because of that, I couldn't be bothered peeling the entire thing off (yes, my mind is weird in that sense!)

Am I right in understanding that this is actually incorrect and that there may be other QR codes on the cell somewhere else on the top? I'm rather curious now so I will gladly rip a few of the tops off to find out more.

As for cleaning them, yeah I need to get some rubbing alcohol to do that.

Some people has been outright lied to and were seriously fucked, so yes we are a little protective.
Seems to be a standard MO of our far eastern friends to start selling good cells and then start slipping the rejects into the pipeline.
But you seem to have taken all precautions and got good cells.

Oh, I know all about being screwed over (happened to me too), and I am going back to the cells (whenever I can) to re-check them every time there's a reply, so thanks to you and everyone for everything!

 

[Alkaline]

Clean that cell wipe all the glue off with rubbing alcohol gently you'll find out. Some people will be upset with you, maybe you will be upset as well, but the truth will be revealed.

 

[Nightguest]

Clean that cell wipe all the glue off with rubbing alcohol gently you'll find out. Some people will be upset with you, maybe you will be upset as well, but the truth will be revealed.

I'm more than happy to do that when I get the chance to, thanks for the tip.
For that, I need to get rubbing alcohol, and that would most likely be Monday/Tuesday, though I will make sure to leave a post here when I get that done.

With all that said and done, I am infinitely curious regarding a very specific point.
From my perspective, these cells over-perform what was sold to me both in terms of amp hours and watt-hours (and with that the average voltage during a discharge test, something very important to me). Furthermore, from the start, I have fully expected to be getting EVE grade B cells.

So my question is, why would I be upset at this? I am somewhat worried that I may be missing a very important point here.

I do get that your frustration is aimed at sellers and the skullduggery that is very common, however, I don't see how it applies here, given my expectations and my results thus far.

 

[Alkaline]

Capacity is not a good measure of a cell, nor is it the primary reason why cells are grade A. Self Discharge is a much bigger issue, this is that when cells are resting grade B will discharge at a fast rate and will eventually become unbalanced which requires that you now fully charge and rebalance them.

Then you also have cells that simply are unable to hold voltage when you draw power form them, these cells prematurely jump to fully charged voltage and also will plummet prematurely to low voltage during charging and discharging.

In other words its not what each cell does on its own, its how they behave in a pack. Grade A cells behave properly and work together. Grade B cells usually require extra attention.

Also rarely sometime you get a truly bad cell, these will be very low in capacity, maybe bloated, and may be leaking as well, basically a cell that would need to be discarded.


I have built both grade A and grade B packs, and while they can work, they require extra effort. I built 2 8s grade B packs, one from was vendor called Basen and I would say it was "ok" the other was from Xuba and 2 of the cells were not, I would not want to build a grade B pack again due to the stress/nonsense.

NOTE: in my situation I was drawing over 80 amps so perhaps my needs were not what a typical battery would need, so maybe in lower amp draw it would fine.

They were EVE 280 Cells and I could have sworn my 2 xuba cells were going to test to less than 170 AH, to my surprise the cells I though were garbage still did about 260... That is why I don't think capacity is a good measure of a cell, plenty of grade B cells can easily match the stated capacity without much effort.

 

[Nightguest]

Capacity is not a good measure of a cell, nor is it the primary reason why cells are grade A. Self Discharge is a much bigger issue, this is that when cells are resting grade B will discharge at a fast rate and will eventually become unbalanced which requires that you now fully charge and rebalance them.

Then you also have cells that simply are unable to hold voltage when you draw power form them, these cells prematurely jump to fully charged voltage and also will plummet prematurely to low voltage during charging and discharging.

On those points, I totally agree.

I look at the capacity in two ways, first the reported Ah from ZKE, and second, a semi-custom calculation, the measured Watt-hours divided by the average voltage reported for the discharge test.

Here is a test from earlier on and it may explain why I'm quite positive about this batch.



Important: Yes this is just 1 out of 16, it doesn't prove that everything is great. However...as I mentioned before I forgot to take screenshots of the other cells (I think I've got like 4 in total). That said, part of why I didn't take screenshots was that they were so similar that I just ended up marking the cells myself and starting the next test. I might go back and test another few to get precise numbers though, as I do regret not saving the data.

The way that I analyze this chart is:

• It sustained the voltage pretty well.
  • I know that this is just 40A and that if I tested at 80A the voltage sustain could be a lot worse, however, this is the best that I can do right now.
  • I program my BMS to cut off at 3.0V, I know that technically this means I'm not discharging to 0% however, I feel that it's "nicer" on the cells as I know they are not grade A and I do want to use these long term. So, to me, this cell is pretty perfect.
• Measured Ah from ZKE reports 294.70Ah
• The measured Watt-hours is 955.26
• The average voltage is 3.24
• Calculated Ah (Wh/average voltage - 955.26/3.24) is 294.83
  • Honestly, that result threw me off as usually the calculated capacity is lower than the measured one with the ZKE testers, but here it seems to be a tiny bit higher.
• I look at both measured and calculated capacity as I've heard arguments for both calculations and well, I'm actually extremely cynical when it comes to products I purchase so I look for the worst.

With all that said, please do let me know if there are any mistakes in my methodology.

Regarding resting voltage. That is something I'm testing now. I've charged 8 of them to 3.65V at 40A (1A cut-off) and have put them back into the cases while I mess around with the other 8.

If you do not mind advising me, how long do you think I should leave the cells to rest before checking the voltage to get a rough idea of their resting behaviour?

Edit:
I finally made that edit to the original post making it clear that the grade A marketing is BS regardless of results.

 

[Alkaline]

NT, did not read OP's response properly....

 

[42OhmsPA]

... Woooosahhhhhh.

I see you have no intension of showing a clear image of the QR Code. At this point its no point in going forward, as far as I'm concerned you are compromised in promoting QSO.

I'm more than happy to do that when I get the chance to, thanks for the tip.
For that, I need to get rubbing alcohol, and that would most likely be Monday/Tuesday, though I will make sure to leave a post here when I get that done.