The 280K just does not match or come close to what EVE is claiming these are the grade A 280K with the official manufacturer test report. At this time I don’t recommend anyone buy the 280K regardless of it being a grade A or grade B. Some say it's because EVE decided to sacrifice capacity in lieu of Longer cycle life (6000 cycles vs the 3500 cycles of the 280N and 304).
One thing that is very strange is that these Cells may come short on the AH but they will come above the WH rating, the 280K is a 896WH cell and 280AH cell with a nominal voltage of 3.2 (nominal is the average voltage of the discharge curve).
My Results
278.4 & 901.4 WH, Luyuan Test Report said I should be getting
289.4 AH on these Matched & Batched Cells Genuine grade A:
https://diysolarforum.com/threads/what-is-going-on-here-just-got-zke-40.49076/
shane_Uk with Luyuan Genuine matched & batch results
276 AH vs the 289 Ah on the sheet; did not show WH, but I suspect it would probably be around 900 or more:
https://diysolarforum.com/threads/opinions-welcome-for-newbie-lifepo4-battery.47310/
18650batterystore.com grade A results, a person named Dena M. Says
277.7 AH (did not show WH, but again I suspect it would be around 900ish maybe 901):
https://www.18650batterystore.com/products/eve-lf280k#looxReviews
Fogstar UK grade A EVE 280, Cajocars gets
280.5 AH & 907.5 WH EVE stated Capacity was supposed to be
293.9 AH…, but still first person with a 280K to actually break the 280 barrier…but just barely
https://diysolarforum.com/threads/just-bought-16-280ah-a-grade-from-fogstar.51027/page-3#post-662021
So something is up, grade A 280K with manufacturing test report are having a hard time meeting the 280AH capacity which is very different form the original 280N and current 304, as these have NO problems meeting both AH and WH.
Now let's look at grade B 280k:
Docan 280K results, very detailed thread by basecamp, but average
263 AH and 850WH
https://diysolarforum.com/threads/poor-docan-experience-resolved.48592/#post-618121
Docan 280K Results by Ce Ce,
265 WH and 860 WH, tested a few cells but this was the average:
https://diysolarforum.com/threads/disappointing-eve-280k-results.47555/
Docan 280K results by gonmag8
265 AH & 863.5 WH:
https://diysolarforum.com/threads/disappointing-eve-280k-results.47555/post-606579
Docan 280K by atti
270Ah & unknown WH:
https://diysolarforum.com/threads/eve-lf280k-capacity-test.49961/
I don’t want to just post Docan links but it seems they dominate the market probably sell 10x as many cells as all others combined so the test results all seem to be from them.
So yeah, Grade A with test report 280K is going to barely meet AH and will probably fall 1-2 AH short, it will exceed WH ratings though, and based on Ray’s testing this is consistent with his testing 276-278 ish AH, however he didn’t give us the WH so again its probably around 900 ish as we see with the others.
But Grade B 280K, yeah… I would not touch with a 10’ pole, we are right there with my low quality xuba cells that are now almost 4 years old 850 ish WH and 860 ish AH.
I’m not sure what type of Grade B docan’s Ray has, maybe they were 280N? Or Pre 2021 280K? DIfferent EVE factory perhaps? But the current 280K grade B supply reflects the grade A 280K and if they are having a hard time meeting capacity there is no chance grade B 280K will.
My recommendation is to avoid the EVE 280K grade A or B all together until a proven stable supply becomes available. If you want Grade A look at the EVE 304, they seem to be just like the original 280N but more capacity and are meeting both AH & WH.
If you are looking for Grade B Docan’s CATL 280 appears to be doing well testing well into the 295’s and higher. Other options would be 18650 grade B REPT 280s.
Lastly, I'm taking a screen grab of the video and will find out if the sun fun kits cells are luyuan cells, I'll ask them on Alibaba and see what they say, Lampard Li can usually tell who is the buyer of the cell based on the qr code / serial number.