Efest IMR18650 3100mAh (Purple) 2014
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Official specifications:
- Top: flat top
- Bottom: non-protected
- Typical Capacity: 3100mAh
- Min capacity: 3100mAh
- Max discharge current: 10A
- Pulse discharge current: 20A
- Quick charge current: 3000mA (1C)
- Quick discharge current: 2000mA
- Cycle life: 300 times
- Charge cut-off voltage: 4.2V ± 0.5V
- Charge cut-off current: 5A
- Initial Impedance: Max: 15mOhm
- Discharge cut-off voltage: 3.0V
- 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
- Size: weight: 50g, Length: 65 mm, Diameter: 18mm
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High power and high capacity in the Efest purple line of high current cells.
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Looking at this curve I will say that 20A is a bit high for continuous load, but 10A is handled very fine.
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I had an accident during testing and I am missing one cell in some tests. The problem was that my load did not turn off after the 20A and discharged the cell completely.
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Conclusion
The cell cannot match the ultra high current cells in power, but easily surpass them in energy at 10A. This is very good performance.
I will call it a acceptable cell.
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
Compare to 18650 and other batteries