Vapcell INR21700 4000mAh K40 (Black) 2021
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Official specifications:
- Model: K40
- Size: 21.1*70.6mm
- Typical Capacity: 4000mAh (0.2C discharge)
- Min capacity: 3900mAh (0.2C discharge)
- Nominal voltage: 3.60V
- Max Continuous Discharge Current: 30A
- Max Discharge Current: 45A with 80°C cut
- End-of-charge voltage: 4.20V
- End-of-discharge Voltage: 2.5V
- Weight: 68g ( Appr)
- Internal resistance: 10mOhm ( Appr) AC 1kHz
- Standard Charge: 2000mA,CCCV 100mA cut-off
- Quick Charge Current: 6000mA
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This is a high current 21700 cell with good capacity.
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The two cells tracks nicely and usable capacity do not go down much with higher loads.
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Conclusion
These cells are good high current cells with a decent capacity.
Notes and links
The batteries was supplied by Vapcell for review.
How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries
Graphical comparison to 18650 and other batteries
Table with all tested LiIon batteries