Efest IMR26650 4200mAh (Purple) 2017
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Official specifications:
- Rated capacity: 4200mAh
- Nominal voltage: 3.7V
- Voltage at end of discharging: 2.5V
- Max. charging current: 4A
- Standard charge: 2A
- Discharging current 35A
- Pulse discharging current: 50A
- Charging temperature range: 0°C ~ 45°C
- Discharging temperature range: -20°C ~ 75°C
- Inner resistance: 20mOhm
- Cell size: 18.5 (±0.2)mm x 65.2 (±0.2)mm
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This is a high current 26650 battery.
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It do fairly good up to 20A, at 30A the cell is struggling a to handle the current.
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At 30A I had to terminate the discharge a bit premature due to high temperature (I only had sensor on the B cell).
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Conclusion
This is a fairly good high current cell, but the rating is on the optimistic side.
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