Test / Review: Efest 18650 3100mAh (Black)

Batteries and Chargers Rechargeable Batteries
1

Efest 18650 3100mAh (Black)



Official specifications:

  • Efest 18650 3100mAh 3.7V Protected (Nipple)
  • Nominal Capacity: 3100mAh (0.2C, 2.50V discharge)
  • Minimum Capacity: 2950mAh(0.2C, 2.50V discharge)
  • Charging Voltage: 4.2 ±0.05 V
  • Nominal Voltage:3.6V
  • Charging Method CC-CV (constant voltage with limited current)




This battery uses a unusual construction with the protection mounted at the + pole. The maximum current from this battery is not very high, probably due to the unusual protection placement.





















Protection trip current is to low to show in the chart.





Conclusion

This battery uses a very good cell and is one of the shortest 3100mAh protected batteries, but due to the low current limit it will not work in all lights (The problem is XM-L lights).



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

2

thanks for the review work!!

but the cell product itself .. yuck! ;)

3

When I bought my last lot of 18650’s from efest, I almost bought these. Glad I got the Panasonics instead :smiley:

Thanks for the review, as always.

4

You guys do realize that there are flashlights that pull less than 2A out there with too little space for regular protected cells? I think thats pretty innovative.

Great review as usual HKJ, thanks. :)

5

But don't I see 5 amp discharge curves?

6

They where a bit short, only one data sample.

7

Thanks very much! Frontpage’d and Sticky’d.