Test/Review of Efest IMR18500 1000mAh (Purple) bt 2014

1 post / 0 new
HKJ
HKJ's picture
Offline
Last seen: 1 week 4 days ago
Joined: 05/24/2011 - 12:23
Posts: 7447
Location: Copenhagen, Denmark
Test/Review of Efest IMR18500 1000mAh (Purple) bt 2014
Efest IMR18500 1000mAh (Purple) bt 2014

DSC_6816

Official specifications:
  • Typical Capacity: 1000mAh
  • Min capacity: 900mAh
  • Continuous Max. Discharging Current: 15A
  • Continuous Max. Charge Current: 2.15A
  • Cycle life: 300 times
  • Battery WH: 125WH\Kg
  • Discharge cut-off voltage 3.0V
  • Voltage: 3.7V
  • Weight: 45g
  • Length: 49.9mm
  • Diamter: 18.21 mm
  • Top: Nipple
  • Bottom: non-protected
  • Full Charge voltage: 4.2V
  • Temperature: discharge temperature range:-10°C—60°C, charge temperature range: 0°C—40°C
  • Storage: 1 year:-20°C—25°C, 3 months:-20°C—45°C, 1 month:-20°C—60°C

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-info

A 18500 cell with a very high maximum current, the rating is higher than for many 18650 cells. This means the cell has a fairly low capacity.

DSC_6815

DSC_6817 DSC_6818

DSC_6819
DSC_6820

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-Capacity

They batteries has very impressive high current handling with nearly constant capacity. There is a slight difference in the internal resistance between the two cells, this may be due to my connection or due to the button top.

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-CapacityTimeHours

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-CapacityTime

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-Energy

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-PowerLoadTime

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-TripCurrent

Efest%20IMR18500%201000mAh%20(Purple)%20bt%202014-Charge



Conclusion

These battery has very good high current performance, but the size limits the capacity (If you have 15mm more length, you can get more than twice the capacity). The cells has slight lower performance then their flat top counterpart.
With the performance of these cells, I will call it a good battery.



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/