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

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

DSC_6804

Official specifications:
  • Weight: 50g
  • Size: 65.69mm(L)x18.30mm(D)
  • Top: Button top
  • Bottom: unprotected
  • Typical Capacity: 2500mAh
  • Discharge temperature range: -20°C—60°C
  • Charge temperature range: 0°C—45°C
  • Storage: 1 year: -20°C—25°C, 3 months: -20°C—45°C, 1 month: -20°C—60°C

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

Efest high current 18650 in button top version, again with the optimistic 35A rating.

DSC_6803

DSC_6805 DSC_6806

DSC_6807
DSC_6808

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

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)%20BT%202014-CapacityTimeHours

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

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

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

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

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



Conclusion

The button top will add a very small resistance and reduce the performance slightly at very high currents.
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.



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/

Ruke
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Awesome review as usual!!!

Would you say there is only very minor or almost nil performance difference compare to the flat top version?

HKJ
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Ruke wrote:
Awesome review as usual!!! Would you say there is only very minor or almost nil performance difference compare to the flat top version?

If you want to use it for really low sub-ohmic vaping, I would go for the flat top version.

But below 15A the difference is insignificant.

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

lagman
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Thank you so much!
I wonder why there aren’t more people saying thank you… I guess it’s because it spreads out on your (many) posts.
Thanks!

My English isn’t perfect but I’m trying to improve it. If you see something that doesn’t sound right or is just plain wrong, please feel free to point it out! Smile

M4D M4X
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you are right lagman…

THX HKJ for your great – never restless work !

PLEASE NOTE
i do not work in "reviews, deals and codes" for the time being
maybe M4D M4X will return one day, but until then:

THANK YOU FOR YEARS OF YOUR SUPPORT AND FRIENDLY CONTACTS!

Desmo
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Truly appreciate your contributions here HKJ

ri chevy
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Most all of us here are ALWAYS appreciative of Henrik’s work. Beer
It is always top notch, unbiased, and done with a high degree of professionalism and integrity. Beer

Vladimir
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Your reviews helped me greatly in selecting chargers and batteries.
Thanks!

Calmaja
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Thanks you (again and again) HKJ.

cocoschnauzer
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I have to say thank you too. Your wonderful reviews did help me on deciding which charger and batteries to buy.

Fritz t. Cat
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Thanks. I have the flat top version in my best light. Nice to know it works well.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

dangerous
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This 18650 seems to track just under the LG HE2 and Samsung 25R, so I could see them using cells from one of those series.

BLF

Billy X
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I rate this member as a cornerstone of BLF Wink

HKJ
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lagman wrote:
I wonder why there aren't more people saying thank you... I guess it's because it spreads out on your (many) posts. Thanks!

 

Embarassed

I do appreciate a thank you, but a long list each time I post a review is way to much.

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

DanielM
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Thank you so much HKJ, your reviews help shed some light (pun intended) on this complicated and crowded market today.

Old-Lumens wrote:
I love modding, but I don't have much use at all for flashlights in general.