Test/Review of Efest IMR18650 2500mAh (Purple) 2014

HKJ

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Mar 26, 2008
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Copenhagen, Denmark
[SIZE=+3]Efest IMR18650 2500mAh (Purple) 2014[/SIZE]

DSC_5253.jpg


Official specifications:
  • Capacity: 2500mAh
  • Min. Capacity: 2400mAh
  • Nominal voltage: 3,6 - 3,7V
  • Charge voltage: 4,20V ±0,05
  • Discharge voltage: 2,75V
  • Max discharge current: 35A (14C)
  • Positive pole: Flat Top
  • Protection circuit (BMS): no (unprotected)
  • Diameter: 18,40mm ± 0,1
  • Height: 65,25mm ± 0,2
  • Weight: 48g ± 1
  • Charging methode: CC-CV

Efest%20IMR18650%202500mAh%20(Purple)%202014-info.png


This is a very high current battery, but the 35A rating might be a bit optimistic.

DSC_5252.jpg


DSC_5254.jpg
DSC_5255.jpg


DSC_5256.jpg

DSC_5257.jpg

DSC_5258.jpg



Efest%20IMR18650%202500mAh%20(Purple)%202014-Capacity.png


These curves shows a very good battery, there is a good tracking between the batteries and not much capacity drop from 0.2A to 20A.

Efest%20IMR18650%202500mAh%20(Purple)%202014-CapacityTimeHours.png


Efest%20IMR18650%202500mAh%20(Purple)%202014-CapacityTime.png


Efest%20IMR18650%202500mAh%20(Purple)%202014-Energy.png


Efest%20IMR18650%202500mAh%20(Purple)%202014-PowerLoadTime.png


Efest%20IMR18650%202500mAh%20(Purple)%202014-TripCurrent.png


Efest%20IMR18650%202500mAh%20(Purple)%202014-Charge.png




[SIZE=+3]Conclusion[/SIZE]

Usual a battery with unspecified cell will not get better rating than acceptable, but there is no doubt this is a very good cell that is used here.



[SIZE=+3]Notes and links[/SIZE]

The batteries was supplied by Akkuteile.de 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
 
Last edited:

TEEJ

Flashaholic
Joined
Jan 12, 2012
Messages
7,490
Location
NJ
Thanks for your review excellent job as usual!

:twothumbs
 

Patt

Enlightened
Joined
Apr 17, 2014
Messages
438
Location
Belgium
I think it's the same cell as these ... "Samsung INR18650-25R 3.6V 2500mAh" ... :wtf::D both very very good... :rock::twothumbs
 

G.Brooks

Newly Enlightened
Joined
May 3, 2014
Messages
13
Thank you for the review.
Will it be ok to my Olight M22 ,or there are better options ? Let's say I want only IMRs.
 

uniformsierra

Newly Enlightened
Joined
Jun 30, 2014
Messages
1
Panasonic has some 2900mAh

Neither of the batteries are old style IMR chemistry, but uses more modern chemistry to get the higher capacity.


@ HKJ,
what makes you say this? what is the difference between the old style and the new?
what i am thinking is the tendency for manufacturers to use Nickle in their cells to help with capacity - is this what you mean?

PS - cheers for all your awesome effort in testing, you rock :rock:
 
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