Test/Review of Efest IMR18650 3100mAh (Purple) 2014

Batteries and Chargers Rechargeable Batteries
1

Efest IMR18650 3100mAh (Purple) 2014



Official specifications:

  • Top: flat top
  • Bottom: non-protected
  • Typical Capacity: 3100mAh
  • Min capacity: 3100mAh
  • Max discharge current: 10A
  • Pulse discharge current: 20A
  • Quick charge current: 3000mA (1C)
  • Quick discharge current: 2000mA
  • Cycle life: 300 times
  • Charge cut-off voltage: 4.2V ± 0.5V
  • Charge cut-off current: 5A
  • Initial Impedance: Max: 15mOhm
  • Discharge cut-off voltage: 3.0V
  • Temperature: discharge temperature range:-10°C—60°C, charge temperature range: 0°C—40°C
  • Storage: 1 year:-20°C—25°C, 3 months:-20°C—45°C, 1 month:-20°C—60°C
  • Size: weight: 50g, Length: 65 mm, Diameter: 18mm




High power and high capacity in the Efest purple line of high current cells.










Looking at this curve I will say that 20A is a bit high for continous load, but 10A is handleded very fine.









I had an accident during testing and I am missing one cell in some tests. The problem was that my load did not turn off after the 20A and discharged the cell completely.







Conclusion

The cell cannot match the ultra high current cells in power, but easily surpass them in energy at 10A. This is very good performance.

I will call it a acceptable cell.



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
Compare to 18650 and other batteries

2

Thank you HKJ for the review. I compared this to the NCR18650BD using HKJ’s 18650 comparion and they were exactly the same.

3

As always, great test! I'm especially happy to see this because I'm actually about to start testing a pair of these today.

You might want to start using a darker gray for your 20A graphs because it's almost impossible to see on my screen.

4

NCR18650BE*

http://dampfakkus.de/akkutest.php?id=536

5

Strange, I thought BD was the hybrid battery (successor of the PD) capable of 10A discharge, while BE was the cheaper version of NCR18650B with only a 3.5A discharge.