Test / Review: Efest 16340 850mAh (Black)

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HKJ
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Test / Review: Efest 16340 850mAh (Black)

Efest 16340 850mAh (Black)

DSC_1767

Official specifications:

  • Operating voltage: 3.70
  • Capacity: 850mAh
  • Ultra-high capacity and premium built quality
  • Protected to avoid over-charged or over-discharged
  • Built-in PCB protection board


Efest%2016340%20850mAh%20(Black)-info

This battery is a short 16340 battery, making it easier to fit instead of a CR123 battery.
The capacity is considerable lower than specified as is usual the case with 16340 batteries.
Internal resistance is calculated between 1A and 2A.

DSC_1766

DSC_1768DSC_1769

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Efest%2016340%20850mAh%20(Black)-Capacity

There is a large difference in performance between the two batteries, this is not good for use in series.
Their upper current limit is also rather low, the performance at 2A is not very good.

Efest%2016340%20850mAh%20(Black)-CapacityTimeHours

Efest%2016340%20850mAh%20(Black)-CapacityTime

Efest%2016340%20850mAh%20(Black)-Energy

Efest%2016340%20850mAh%20(Black)-PowerLoadTime

Efest%2016340%20850mAh%20(Black)-TripCurrent

The two batteries does not have the same protection threshold , one is at 2.9A, the other at 5A.

Efest%2016340%20850mAh%20(Black)-Charge



Conclusion

I am not very impressed with these batteries. They can be used on at a time, but with the differance in capacity, they are not very good for use in series.



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
Comparison to other LiIon batteries

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

Edited by: sb56637 on 08/26/2014 - 17:45
DimBulb
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HKJ wrote:
Internal resistance is calculated between 1A and 2A.

And is 1/4 ohm like the table says?

The curves may show different values for this but I can’t make out the color legend.

HKJ
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DimBulb wrote:
HKJ wrote:
Internal resistance is calculated between 1A and 2A.
And is 1/4 ohm like the table says?

Yes, the DC resistance is 0.25 ohm.

DimBulb wrote:
The curves may show different values for this but I can't make out the color legend.

Next time I generate curves the legend will use thicker lines.

The internal resistance is calculated from the "Protection Test" curve and you will not get much help in reading that from thicker legend lines.

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

DimBulb
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With that curve I get (4-3.5)v/(3-1)A = 0.25 ohm or (4-2.3)v/(5-1)A = 0.43 ohm, avg.

Seems like nothing with cells gives a straight line and coming up with a formula for even a single discharge curve would be pretty difficult.
Back to the piece-wise linear approach. Sad

SashiX
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Hm, mine have bigger nipple Flat Stare
http://budgetlightforum.com/node/18593

And… this review shows that they are better than AW at 2A Flat Stare Well, they are better in general.
What happened here? First XX good samples and then… s%&t ??? Very disappointed Sick

HKJ
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DimBulb wrote:
With that curve I get (4-3.5)v/(3-1)A = 0.25 ohm or (4-2.3)v/(5-1)A = 0.43 ohm, avg. Seems like nothing with cells gives a straight line and coming up with a formula for even a single discharge curve would be pretty difficult. Back to the piece-wise linear approach. :(

That is the reason I calculate it between 1A and 2A, when you put a heavy load on a cell the curve will not be linear and you will get to high a value (Except if you plan to use the battery at high currents).

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

MRsDNF
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Thanks HKJ. We need a 3000 mAh capable of 3.5 amp discharge in this size package. Next year maybe. Cheers.

My current and or voltage measurements are only relevent to anything that I measure.

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djozz
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Thanks for another usefull test, I'll stick to my Nitecore 16340 then.

link to djozz tests 

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sb56637
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Thanks very much for the review! Frontpage’d and Sticky’d.

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sirockalot
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scheven_architect wrote:
where can you buy these :)?

is this a 16340 http://www.fasttech.com/products/0/10001848/1134001-nitecore-nl166-rcr12... ?

yes they are, I have a few