I have some CATL 280Ah to test.
Riden 6018 with 10ga Leads.
Set to 3.65 CC
Charges at 18A
Voltage gets to 3.65 and current drops to <1
Multimeter confirms 3.65 at cell terminals
Rested for about an hour.
Connected to ET5410 with 10 Ga leads
Set to 38A 2.5A
Got 260Ah.
I recharged...