BATTERY SELLERS - THE GOOD, BAD, UGLY -- or Jenny (DOCAN) so far so good ...

[Cheap 4-life]

This EV grade vs energy storage grade is non-sense. Don't fool yourself or others with this terminology. Docan wants to confuse you, that's how they can ask a premium for trash. They are either deemed suitable for battery pack or they are not.

This makes no sense to me.. what other terminology would you suggest. There is obviously cells that do not meet the manufacturers strict EV requirements. That can be because they have more than rated capacity or less because all the cells in the EV packs need to be the exact same. Or other parts of the puzzle you mention that are not quite up to spec or exactly the same for EVs.. those are the cells that most on this forum and apparently most everywhere are buying for solar storage.. they are suitable for solar storage battery packs.. not every cell as there’s sometimes bad cells that won’t play nice with other cells. That would of course occur more often with the cells that didn’t meet up to the manufacturers EV specs.. from what I read Docan will simply replace those cells if you happen to get one..

 

[Chris30559]

This makes no sense to me.. what other terminology would you suggest. There is obviously cells that do not meet the manufacturers strict EV requirements. That can be because they have more than rated capacity or less because all the cells in the EV packs need to be the exact same. Or other parts of the puzzle you mention that are not quite up to spec or exactly the same for EVs.. those are the cells that most on this forum and apparently most everywhere are buying for solar storage.. they are suitable for solar storage battery packs.. not every cell as there’s sometimes bad cells that won’t play nice with other cells. That would of course occur more often with the cells that didn’t meet up to the manufacturers EV specs.. from what I read Docan will simply replace those cells if you happen to get one..

I agree, granted I have not received my cells yet. I would assume in the EV industry, physical space is very limited, so I could also believe they would reject any cell that does not meet the maximum AH/size they set forth.

As far as these side code catl 280ah that are measuring upwards of 300ah I suspect they are really the 304ah cells that failed to reach full capacity during the EV tests, so they mark them as 280ah, put a new black top with QR code and slightly lower price for DIY. As far as I can tell the physical sizes of these 280ah side codes are the same as the 302ah cells but cannot confirm. Has anyone else already come to this conclusion? I will hopefully get my cells in the next couple weeks and will update test results when I do.

Of course I am new to the DIY cells so I could be totally out in left field.

 

[brum]

@Alkaline directed me to this thread. I'm in the same situation - CATL 280Ah cells are on their way. I got a bit afraid of what I'll be getting if these have fake QR codes.

I googled a bit the CB310 and found other pictures (not from Docan) with the same QR code position. Moreover - the video below is a year-old video for the same QR code location, but for cells ordered from Aliexpress. Another image pointed me to Facebook and it directed me to a page that is related to "evlithium", no trace of Docan there.

So it is unlikely that Docan is doing this. To me, it seems more likely a CATL thing. Otherwise, it would be a great conspiracy theory that multiple resellers are putting fake QR codes the same way. Think a bit about it. If you can create a fake QR code why not put it in the same place as the original one?

So as long as the cells are not bloated and they pool the stated capacity I would be fine. Yep, I understand the common impression that we are getting grade B cells, but this is just an impression. Only time will show if our cells are good or not.

 

[Alkaline]

I just want some clarification but is DONCAN and DOCAN the same company? I just realized form the title of the thread.

 

[brum]

It is a typo. I see people use both but still refer to the same salespersons. Moreover - there is no Doncan seller on Alibaba. The full name is "Docan Technology(ShenZhen) CO.,Ltd.".

 

[Alkaline]

@Alkaline directed me to this thread. I'm in the same situation - CATL 280Ah cells are on their way. I got a bit afraid of what I'll be getting if these have fake QR codes.

I googled a bit the CB310 and found other pictures (not from Docan) with the same QR code position. Moreover - the video below is a year-old video for the same QR code location, but for cells ordered from Aliexpress. Another image pointed me to Facebook and it directed me to a page that is related to "evlithium", no trace of Docan there.

So it is unlikely that Docan is doing this. To me, it seems more likely a CATL thing. Otherwise, it would be a great conspiracy theory that multiple resellers are putting fake QR codes the same way. Think a bit about it. If you can create a fake QR code why not put it in the same place as the original one?

So as long as the cells are not bloated and they pool the stated capacity I would be fine. Yep, I understand the common impression that we are getting grade B cells, but this is just an impression. Only time will show if our cells are good or not.

So here is probably what is happening a wholesaler buys these CATL (cells that failed testing) the wholesaler than applies a FAKE qr code and then sells these to alibaba/express sellers who then sell them to you. So 1 shop probably does the lasering and then supplies the grade B cells to all that are looking to resell.

Sorry but Docan is doing exactly this:

BATTERY SELLERS - THE GOOD, BAD, UGLY -- or Jenny (DONCAN) so far so good ...

But Docan gave me all the numbers before I even when to the PayPal page. Once I pay for the transaction, I have never got any additional fees. It's very clear how much it will be to get those cells to my door. I do not get what you are saying. It's pretty well established that if a store...

diysolarforum.com

So not needed they can advertise them as Value Grade or Storage Grade and be just fine. But they go around saying TOP GRADE and other stuff. I suppose it works only 1/10 people will actually test probably 1/20.

BTW people have tested the CATL 280 they are pulling close to the rated 280AH from Docan.

 

[upnorthandpersonal]

It is a typo.

Fixed it.

 

[brum]

BTW people have tested the CATL 280 they are pulling close to the rated 280AH from Docan.

This is not sufficient to mark a cell as good. What is equally (or even more) important than capacity is internal resistance. But if IR and capacity are fine - then I consider these as grade A cells on my scale.

Capacity life is another story. I'm living it outside the picture for now. The only way to see if we got crappy short-life cells is to wait a couple of years.

 

[740GLE]

Voltage slump is also important, what’s the point of having a 280ah pack if you can’t pull more than 50a before voltage starts to go to trash after 100ah or so.

 

[brum]

Voltage slump is also important, what’s the point of having a 280ah pack if you can’t pull more than 50a before voltage starts to go to trash after 100ah or so.

Voltage slump is caused by high IR.

IR is not constant. It changes with SOC and temperature. And these are affected by the load. The higher the SOC is, the higher the IR gets. The colder the cell is - the higher the IR gets. So batching of cells should be done with IR measured at the same SOC and temperature. Usually ~30-40 SOC (as this is when it matters more).

 

[Cheap 4-life]

@Alkaline directed me to this thread. I'm in the same situation - CATL 280Ah cells are on their way. I got a bit afraid of what I'll be getting if these have fake QR codes.

I googled a bit the CB310 and found other pictures (not from Docan) with the same QR code position. Moreover - the video below is a year-old video for the same QR code location, but for cells ordered from Aliexpress. Another image pointed me to Facebook and it directed me to a page that is related to "evlithium", no trace of Docan there.

So it is unlikely that Docan is doing this. To me, it seems more likely a CATL thing. Otherwise, it would be a great conspiracy theory that multiple resellers are putting fake QR codes the same way. Think a bit about it. If you can create a fake QR code why not put it in the same place as the original one?

So as long as the cells are not bloated and they pool the stated capacity I would be fine. Yep, I understand the common impression that we are getting grade B cells, but this is just an impression. Only time will show if our cells are good or not.

I asked Amy Docan why they covered up the original QR code. This is the response.

“Yes, CATL brand they don't supply their batteries for retailers, they only directly supply to the big company. So we have to hidend and remove the big QR code in the center.We use another company to purchase this batteries from the factory, the corner small code also original QR code from CATL factory.”

“This battery you can test the capacity, if they are not high quality , they can not test out over 280Ah. My customer tested the capacity is 299Ah.Only Grade A battery can get higher capacity than battery specification”.

Thank you very much
Amy Zheng

“So we have to hidend and remove” it does appear to be a “Docan thing”. Although other retailers might be doing the exact same thing.

 

[Alkaline]

This is not sufficient to mark a cell as good. What is equally (or even more) important than capacity is internal resistance. But if IR and capacity are fine - then I consider these as grade A cells on my scale.

Capacity life is another story. I'm living it outside the picture for now. The only way to see if we got crappy short-life cells is to wait a couple of years.

I agree, but money talks so the reason 9/10 sellers have grade B stock is people are buying them.

I won't because 2 years in I'm already down 258/280 with just like 15 or cycles and other issues. SO yeah If I can get 300 cycles from these that would be a plus, forget the 2000+ they advertised.

 

[Chris30559]

Well I finally got my 8 CATL 280 cells from Docan last week. Physically perfect condition, sides flat no swelling what so ever. I top balanced them to 3.55v (didn't feel the need to stress them all the way to 3.65v) and then discharged the full 280ah from them no problem. Discharge current was 40amps, I stopped discharging them after 280ah and the voltage was still 3.16v. based on some of the capacity tables I see on this site they somehow still have 10-15% left in them.

Final thoughts, I am very happy with my purchase from Docan and decision to go with the CATL over EVE cells. Will be buying more for sure.

 

[Hipster]

I also got 8 CALB Cells from Docan - 230ah models and on my 7th cell testing for Cap. so far they all gave over 230ah - they look mint excellent condition - i am happy so far also - having them here in the US - i got them in 5 days - i am also glad i got them over the EVE cells i was first looking to get but they were only in China so i went with the CALB - i think it may even be the better choice over EVE - i only go down to 2.9V and still got over 230ah - 2.9v to 3.6v -

 

[740GLE]

You have pics of the terminals of the 230 cells?

 

[Hipster]

they are welded 6mm studs - soon will finish on Cell 7 and start Cell 8 tomorrow last one - so far they all gave over 230ah not by much but consider that i didnt go down to 2.5V - i stop at 2.9V going down to 2.5v may have got a few more AH - could be 5ah more or a bit less - i am happy so far getting the full 230ah - these have been the best cells in the many years of buying cells - which were all under Cap. by some degree - it took many years of trying to get better cells - besides headway cells a decade ago -

 

[Alkaline]

Take a better picture.... can't tell if its re-lasered or not but there is a slight color difference between where the QR code is and the vent.

What do you get when you use the QR code scanner app?

ALSO... did you catch that the QR code starts with "BAD" could be nothing... could be something. In the end if you are happy with your purchase its what really matters.

 

[740GLE]

I have 8 Eve 230ah cells I picked up back in April from Docan, no complaints with them. Eventually I’ll prob pick up another 8 so I have two 24v banks, good to know CALB appear to be quality units.

 

[Hipster]

Take a better picture.... can't tell if its re-lasered or not but there is a slight color difference between where the QR code is and the vent.

What do you get when you use the QR code scanner app?

ALSO... did you catch that the QR code starts with "BAD" could be nothing... could be something. In the end if you are happy with your purchase its what really matters.

yes i did notice that BAD - i though that was funny also - not all have BAD - they all check out fine with the Code Checker - and all are giving me 230ah - i got some as high as 234ah - the lowest 231 and change - this is from 2.9v to 3.6v - i am not stressing it - these have been the best set of Cells i got ever so far - besides my first set of Headways - that was a decade ago almost - they look mint - no dents - no bloating - no scratches on the posts - recharging the 8th and last cell now - i am glad i went with the CALB - instead of EVE -

 

[Hipster]

here

 

[justgary]

here

Those are "DataMatrix" codes, not "QR" codes. Your "Cell 5.jpg" image decodes as "0B5CB37M55A33LBAC1000497", so it looks like the code is valid. It also looks like you should interpret it bottom line first, then top line.

I put the decoded string into the LFP decoder at https://www.gobelpower.com/lifepo4_decoder.html and found that it is a valid code for a CALB LFP cell, 230 Ah, 3.2 V nominal, born on 12 October 2021.

 

[Hipster]

yes bottom line first - its the same on all cells - the top line is the difference - i checked them all - they all show as a valid code - all show its CALB LF230 - i feel totally fine with them - no reason to think otherwise - i would get CALB again if or when i need more cells - but i think i may be fine for another 10 - 15 years with these before i need any more for my use anyway -

 

[Alkaline]

here

Those look good to me

 

[Hipster]

Those look good to me

i think so - i been buying these things for the past decade and these i have to say are the first ones that i got the full Cap. no dents or bloat or anything that looks bad - wrapping it perfect - besides headways when i first started are great cells - those were brand new top notch and i paid for that - a decade ago - it costed me $1700 i believe and got a 105ah pack out of it - think about that - this 230ah pack is replacing those headways i had for almost a decade now - and i still get 85ah out of them - with these 230ah - i am good for 15 years i would say - almost half the cost now with over double the Cap.

 

[hankcurt]

Those are "DataMatrix" codes, not "QR" codes.

I looked at the photos above and never noticed that these aren't QR Codes.
Has CALB always used DataMatrix to code their batteries?

I tried the LiFePo code scanner app on them and it doesn't work, so apparently it will only read QR Codes, which is a bit of a bummer.

Looking closely at the picture, you can see a "brushed" appearance to the metal around the code and around the vent. The un-etched squares inside the code matrix also have this appearance, which is a good indication that the code is original.