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Samsung 20S - high drain 18650 Li-ion cell's capacity test

Samsung INR18650-20S is a 2000mAh Li-ion cell of 18650 size which supports continuous discharge at up to 30A.
SAMSUNG INR18650-20S Li-ion 18650 30A 2000mAh battery cell capacity test

The battery was bought from my reliable supplier (Queen Battery) and tested with ZKETECH EBC-A20 and a self-made battery holder. It's a PC-connected battery tester supporting 4-wire measuring and discharging at up to 20A.

I've used version 3.0 of my battery holder based on 0.5mm thick pure copper terminals
I've followed all the prescriptions of the IEC61960-2003 standard concerning battery's capacity measurement. Before each discharging cycle each battery was charged at standard charge current mentioned in its datasheet to charge end voltage. Before each discharging or charging i've held a 1-1.5hrs pause. The environment temperature was 23.0-24.5°C. To be sure in results i've done each test minimum twice (usually 3-4 times).


Samsung INR18650-20S

The cell is marked as INR18650-20S SAMSUNG SDI 3 1IA1 which means that the production date is 01 Oct 2018.
SAMSUNG INR18650-20S Li-ion 18650 30A 2000mAh battery cell capacity test

The main specs from Samsung 20S datasheet (pdf):
Capacity (min.): 2000mAh
Nominal voltage: 3.6V
Standard charge current: 1.0A (0.5C)
Rapid charge current: 4.0A (2C)
Charge cut-off current: 100mA (0.05C)
Charge end voltage: 4.20V
Max. cont. discharge current: 30A (15C)
Discharge cut-off voltage: 2.5V
AC impedance at 1KHz: ≤15mΩ
Max. weight: 48g

Measured initial DC IR at 2A in fully charged condition was 11±1

Measured weight of the tested cell was 46.25g
SAMSUNG INR18650-20S Li-ion 18650 30A 2000mAh battery cell capacity test

Samsung 20S capacity test results:
SAMSUNG INR18650-20S Li-ion 18650 30A 2000mAh battery cell capacity test
At 0.2C (or 0.40A) discharge Samsung 20S's capacity is 2165mAh - noticeably higher than the 2000mAh declared and it plays around 2000mAh all the way up to 20A but the energy, of course, decreases. Curves are flawless, without voltage drops and recovers.

Capacity tests showed that Samsung 20S is a great high drain cell and there is nothing to add.

Here is the video version of this review:
SAMSUNG INR18650-20S Li-ion 18650 30A 2000mAh battery cell capacity test

Check out my YouTube channel for batteries, chargers and other stuff reviews.

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