Vapcell deserves recognition that they were able to stock samples of this particular cell. The cells I received last week are probably factory samples as they carry scratches on the tube? Other branded cells from Vapcell always came in perfect mechanical conditions. I tested three samples and their initial parameters correspond to the manufacturer`s specifications of this particular type, also parameter consistency is good.
Nominal (0.2C) capacity / IEC DCIR at 50% SoC measured at 25 °C in temperature chamber
5.0371 Ah / 14.1008 mOhm
5.0266 Ah / 13.9924 mOhm
5.0208 Ah / 13.9593 mOhm
For comparison I am adding the values of a new Samsung 40T3 model:
4.0944 Ah / 14.6298 mOhm
However, according to my measurements, I would rather label those 50S samples as 20A CDR, because at 25A CDR (5C) I measured the temperature of 74 °C at the end of the discharge in a temperature chamber with forced air circulation with temperature of 25 °C. This is significantly more than “established” 5C rated cells. For example 40T3 ends 5C discharge with 59 °C or 30Q6 with 61 °C under the same conditions.