I think you would be better off with the A grade cells. If your system was utilized in a lighter manner, the B grade cells would be OK. B grade from Amy are still good stuff.
Docan 8x EVE 280ah slightly swollen
- Thread starter jay_jay
- Start date
I think you would be better off with the A grade cells. If your system was utilized in a lighter manner, the B grade cells would be OK. B grade from Amy are still good stuff.
Alkaline
Solar Wizard
is grade A 280K really that much better than grade B 280k? I'm not talking overall I'm just asking about this 280K in particular?
Unless someone with the proper testing equipment has both grades in front of them, any answer to that is just speculation. But putting together a system was something I wanted to do once and have it right the first time.
S Davis
Solar Enthusiast
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That’s the problem there is no A and B grade, there is grade A and failed grade A. One passes all the specifications and one does not. It could be any number of reasons for it not to pass.
houseofancients
Solar Wizard
wrong, there's ev grade and storage grade and crap grade..
unfortunatly there's never the same standard , so every supplier and manufactorers grade them different
Alkaline
Solar Wizard
What about recalled EV grade? Has anyone heard of this rumor going around about how EVE had a large customer cancel a lot of 280K cells and these are like grade A- Grade now flooding the market? I know I read a thread about this I think its been deleted or moved...
S Davis
Solar Enthusiast
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From where do you get this information? So where are the spec sheets for these “storage grade B” cells? If there was a real grade B they would put out a spec sheet on them.
I would guess that the spec sheet, as published by the manufacturer, is for the grade A cells. Why would they create a spec sheet for lesser cells?
S Davis
Solar Enthusiast
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Exactly, they are just failed grade A or EV grade would be a better description, we don’t know what parameter they failed to be rejected.
I have also ordered small batch from Docan in March - 16 x EVE LF280K 280Ah, checking QR code the cells were manufactured somewhere in December 2021. Was extremely disappointed to receive swollen batteries - sold as grade A, "new cells". Docan sold some shit to all of us - won't buy anything from them and definitely will recommend avoid Docan!
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Ampster
Renewable Energy Hobbyist
Pictures? Why did you wait until now to post?
I've been provided test report by Docan before purchase.
Ampster
Renewable Energy Hobbyist
Did they not test the same as the report?
Generally, it was a busy time for me since May and the disappointment made me resigned. Recently noticed your thread and wanted share and confirm that I got the same shit. These pictures show deformation of the received batteries - more or less, similar deformation. Batteries are swollen on the thick sides, what is compensated by inward pressure on the thin sides. As you can see on the picure, measured battery has width of 75mm, spec says it should be 72+/-0.5. The swelling is irregular - not in the center but rather on sides, sometimes in the center. When you put cells together, there are distances of 3-7mm (the cell from picture adds about 2mm to such a distance)
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42OhmsPA
What's in a title?
Never new Docan offered test reports, do the cells you received have a docan sticker? Didn't see one in your 2 pics
Ampster
Renewable Energy Hobbyist
Most of my cells from three different vendors had those kind of deviations. They have been working fine for me. This was two years ago before Docan.
The report I was presented, had checking date 2021/8/7. The cells I received had QR code that decodes to December 21/January 22. Moreover, before shipment I was presented with pictures of cells put together that are perfectly square, without distances between them - could not replicate this after receiving the package.
Ampster
Renewable Energy Hobbyist
How was the capacity? Did it test the same as represented?
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That's ok, if you expect this grade B shape and that's the problem with LiFePo4 cells - they have long life expectancy, 3000-6000 cycles. If you were cycling them everyday that gives 8 to 16 years. If you buy the A grade, you expect to have the longevity. If you buy B grade, you still may have a 1000 of cycles remaining - that makes scam difficult to prove after 3 years and you may feel happy for 3 years of work. The point is that Docan purposely presented tests that are not reflecting reality, fake pictures of proper grade A cells etc. I know the cells I received likely will last for a year or 2 (if I will be lucky, it may be 3 or 4) but I was buying with view to use the 8-10 years. It is true that the material they are built of may not last so long as the 10 years is considered somehow a max. And this also makes scam/low quality cells easier to push through as "A grade". Because people are looking for A grade, these companies like Docan become scammers because these batteries - even of grade B - can still last long when used occasionally. Scam is scam and should be exposed.
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