Efest IMR18500 1100mAh (Red)

V1 Flat top

This is the second time I test these cells and the result is the same.



Official specifications:

• Nominal voltage 3.7V
• High current rated
• Lowest permitted discharge voltage - 2.5 V
• Cycle life - 500 cycles
• Max charging rate - 4.5 Amps
• Do not short circuit - High current will be discharged
• Diameter: 18.0 +/- 0.5mm
• Height: 50.0 +/- 0.5mm
• Size: 50,93(L)* 18,10(W)mm

The batteries does track nicely and has nearly the same capacity at any load.











The low capacity can be seen here, the battery is nearly empty before I am finished with the test.





V2 button top



Official specifications:

• Efest IMR 18500
• Brand: Efest Model: 18500
• Capacity:1100mah Material: Li-Mn
• Positive Pole: Button top
• Size: 50,93(L)mm* 18,10(W)mm

The batteries does track nicely and has nearly the same capacity at any load. They do have slightly less capacity than the V1 above, maybe because they have a different age.











The low capacity can be seen here, the battery is nearly empty before I am finished with the test.





Conclusion

These IMR batteries have very good performance at any load, but the capacity is, of course, not that high (For just 15mm more length, it is possible to get double capacity).
At the current time I can only rate them acceptable, because Efest is a new company, and the batteries is not from one of the big brands.



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