Test/Review of Efest IMR18650 2500mAh (Purple) 2016

Efest IMR18650 2500mAh (Purple) 2016

Official specifications:

  • Typical Capacity: 2500 mAh

  • Nominal Voltage: 3.7V

  • Discharge End Voltage: 3.0V

  • Standard Charging Current: 1.5A

  • Charging Voltage: 4.20+–0.05V

  • Max Pulse Discharging Current: 35A

  • Dimensions: 65.11mm (L) x 18.44 mm (D)

  • Weight: 46g

A 2500mAh battery with a fairly high current rating.

The discharge curves look very good, they tracks perfectly and capacity is nearly constant.
The battery got warm at the higher current and I had to stop.

I stopped this discharge a bit early due to temperature.

For now I am running with a fairly low maximum temperature (This trace here melted one battery holder).
Remember the traces are temperature increase, i.e. the actual battery temperature is 25-30°C higher.

Only B battery is valid, the holder for A is melted.

Only B battery is valid, the holder for A is melted.


The battery has good performance, but gets warm at 30A (Not a big surprise).

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