Efest 18650 3400mAh bt (Black) 2014
%202014/DSC_4098.jpg)
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
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-info.png)
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.
%202014/DSC_4097.jpg)
%202014/DSC_4100.jpg)
%202014/DSC_4101.jpg)
%202014/DSC_4102.jpg)
%202014/DSC_4103.jpg)
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-Capacity.png)
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.
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-CapacityTimeHours.png)
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-CapacityTime.png)
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-Energy.png)
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-PowerLoadTime.png)
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-TripCurrent.png)
The protection trips at 6A, but, of course, the limit is lower for continuous draw.
%202014/Efest%2018650%203400mAh%20bt%20(Black)%202014-Charge.png)
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