Test/Review of Efest 18650 3400mAh bt (Black) 2014

Efest 18650 3400mAh bt (Black) 2014



Official specifications:

  • Number: 18650 3400mAh
  • Specifications:3400mAh 3.4Ah
  • Nominal Capacity: 3400mAh (0.2C, 2.50V discharge)
  • Minimum Capacity: 3250mAh(0.2C, 2.50V discharge)
  • Charging Voltage: 4.2 ±0.05 V
  • Nominal Voltage: 3.6V
  • Charging Method: CC-CV (constant voltage with limited current)
  • Charging Current: Standard charge: 170mA, Rapid charge : 3400mA
  • Charging Time: Standard charge : 3hours, Rapid charge : 2.5hours
  • Max. Charge Current: 3400mA(ambient temperature 25°C),
  • Max. Discharge Current: 6800mA(ambient temperature 25°C)
  • Discharge Cut-off Voltage: 2.50V
  • Cell Weight: 55g max
  • Cell Dimension: Height : 69.75mm max, Diameter : 18.57mm max
  • Operating Temperature: Charge : 0 to 45°C, Discharge: -20 to 60°C




As usual with this type of cell I do not test the full capacity, because I stop at 2.8 volt, not the allowed minimum of 2.5 volt.











Very nice discharge curves. Due to the protection circuit the 5A curve is a bit low and one of the batteries stops before it is fully discharge.











The protection trips at 6A, but, of course, the limit is lower for continuous draw.





Conclusion

This is a very good battery.
The protection circuit limits the maximum continuous draw to 5A.



Notes and links

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

Nice review as always HKJ !

Great to have you here and great to have your website full of usefull information !

Thank you for the review!

In HKJ's table it says Cell: Panasonic NCR18650B