That is the same exact type of report I got with my supposed grade A 280K matched and batched from Amy Wan. At this point I think EVE is the culprit, I looked very closely at all 3 people that were selling 280K grade A with reports, and they all are testing in the 278ish range. Go look on 18650batterystore, SFK 280K review section, you'll see people saying the same, and this actually matches my own test 278 with the same ZKE style tester...
I also think this is primarily for cells made in November 2021 - January 2022, it also correlates with the on and off again rumor about some big car / bus company who cancelled a big order from EVE after they were not happy with the results. Perhaps these should have all been grade B but was too big of a hit from EVE so they said F it sell as grade A and just lie about it...
Regardless, I have dealt with Amy Wan twice once in 2020 when she was with Xuba and again when she ran her own company. I don't think I will be dealing with her or any other overseas company. I don't care what grade or what a report a vendor has at this point as I don't even believe EVE themselves, its China after all, the corruption goes up to the top.
I would have accepted a discount per cell, but I am now back listed on her Alibaba chat and its been over 6 months, I should have bought this tester back in February (but who knows, maybe back then they would have passed, 2 AH loss after 8 months is possible???) Actually you know, these should have tested to 284, that really would have put my mind at ease...
My final advise for anyone is that you should only buy in your local country and make sure you can do a return if un happy. Don't believe any grade A or grade B or whatever else, do you own tests and hold the vendor over a barrel. These youtube reviews and cheerleading forum posts have cost me ?
I will have my basen 280 results on the ZKE ready by the morning.