Test/review of Efest IMR18650 3500mAh (Purple) 2017

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HKJ
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Test/review of Efest IMR18650 3500mAh (Purple) 2017

Efest IMR18650 3500mAh (Purple) 2017
DSC_0315
Official specifications:


  • Rated capacity: 3500mAh
  • Nominal voltage: 3.7V
  • Voltage at end of discharging: 2.5V
  • Max. charging current: 4A
  • Standard charge: 2A
  • Discharging current 10A
  • Pulse discharging current: 20A
  • Charging temperature range: 0°C ~ 45°C
  • Discharging temperature range: -20°C ~ 75°C
  • Inner resistance: 20mOhm
  • Cell size: 18.5 (±0.2)mm x 65.2 (±0.2)mm

Efest%20IMR18650%203500mAh%20(Purple)%202017-info
A high capacity 18650 battery that can deliver a fair amount of current.
DSC_0313 DSC_0314
DSC_0316 DSC_0317
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Efest%20IMR18650%203500mAh%20(Purple)%202017-Capacity
The discharge curves shows nice tracking between the two cells. The battery has very low voltage at 20A.
Efest%20IMR18650%203500mAh%20(Purple)%202017-Temp-10.0
The battery gets very warm at 10A discharge current.
Efest%20IMR18650%203500mAh%20(Purple)%202017-Temp-15.0
At 15A I had to stop the discharge due to temperature.
Efest%20IMR18650%203500mAh%20(Purple)%202017-Temp-20.0
I also had to stop at 20A.
Efest%20IMR18650%203500mAh%20(Purple)%202017-CapacityTimeHours
Efest%20IMR18650%203500mAh%20(Purple)%202017-CapacityTime
Efest%20IMR18650%203500mAh%20(Purple)%202017-Energy
Efest%20IMR18650%203500mAh%20(Purple)%202017-PowerLoadTime
Efest%20IMR18650%203500mAh%20(Purple)%202017-TripCurrent
Efest%20IMR18650%203500mAh%20(Purple)%202017-Charge
Conclusion
The cell looks very good, it has lot of capacity and can handle some current, but I will not recommend it above 10A.
Notes and links
The batteries was supplied by Efest 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
Compare to 18650 and other batteries

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/