Barkuti
(Barkuti)
2
Looks like tightly binned PLB 5000mAh NiCoMn cells, or sort of. The discharge performance is a little bit worse.
I have an interesting question in my mind. Observing your discharge graphs, if cells like this or the LiitoKala INR26650-50A were to be charged to 3.6-3.65V, they would still deliver about ⅓ of their maximum specified capacity, but due to the much lower energy and discharge time I believe they could handle up to 35A continuous down to 2.5V. May sound weird, but since they're so cheap they may work good as replacement for UPS batteries or even small cranking batteries (4S charging voltage: 14.4 to 14.6V).
Cheers ^:)