Efest IMR18650 3100mAh (Purple) 2017
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Official specifications:
- Capacity: 3100mAh
- Nominal voltage: 3.7V
- Voltage at end of discharging: 2.5V
- Max charging current: 4A
- Standard charge: 2A
- Discharge current: 10A
- Pulse discharge current: 20A
- Charging temperature range: 0° ~ 45°C
- Discharging temperature range: -20°C ~ 75°C
- Inner resistance: 20mOhm
- Cell size: 18.50 (±0.2)mm x 65.20 (±0.2)mm
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A 18650 with 3100mAh and fairly high current.
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I like the plastic box Efest uses, it is made to protect the battery from impacts.
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The discharge curves tracks very fine.
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I forgot to put the temperature sensor on one of the batteries.
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That means it did run the full discharge curve and got fairly warm
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Especially at 20A (It did not work anymore after this test). This also shows that it has proper safety, that disables the battery if it gets way too hot.
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Conclusion
This cell has good performance at moderate current, but it is not a super high current cell.
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