Test/review of Efest IMR26650 5200mAh (Purple) 2016

Efest IMR26650 5200mAh (Purple) 2016







Official specifications:

  • Nominal capacity: 5200mAh

  • Minimum capacity: 5100mAh

  • Nominal voltage: 3,7V

  • Charge cut-off voltage:: 4.2V ± 0,1V

  • Discharge cut-off voltage: 2.5V

  • Max discharge current continuous/pulse: 15A / 40A

  • Chemistry: LiNiMnCoO2

  • Diameter: 26,22mm ± 0,15mm

  • Length: 66,2mm ± 0,15mm

  • Weight: 92g ± 1




This is a high capacity 26650 with fairly high current.











The discharge curves tracking is good, at 15A the capacity drops significantly and the battery gets too hot.



The batteries gets fairly warm at 10A, but can handle a full discharge.



At 15A they get too hot and I terminates the discharge a bit early, maximum temperature was about 86°C



At 20A the temperature raises to the same level, but the battery is empty before I can register it and stop.















Conclusion

The batteries has good performance with high capacity and performs fine up to 10A, above that it is best to use pulse discharge, to keep the temperature down.



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

Thank you!

I’m going to order 2 of these for my Convoy L6. BTW, I always use unprotected cells in my flashlights. That said, I do monitor them closely when used in series.

Great review, as always.

One thing I've noticed in many of your reviews, is the inconsistent use of decimal mark, often in the same table: some fields use point and some fields use comma:

I understand this could be the result of pasting numbers from different sources, still it would be good to settle on a single representation. Does not matter which one, as long as it's a point :-)

+1

Self-knowledge about battery use and safety is a better way than depending on a ‘protected battery’ which you can only assume would work.

Yes, you got that right