Efest IMR20700 3100mAh (Purple) 2018
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Official specifications:
- Rated capacity: 3100mAh
- Nominal voltage: 3.7V
- Voltage at end of discharging: 2.5V
- Maximum charging current: 4A
- Standard charging current: 2A
- Maximum discharge current: 30A
- Charging temperature range: 0°C ~ 45°C
- Discharging temperature range: -20°C ~ 75°C
- Inner resistance: 20mOhm
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The batteries are not perfectly matches, but fairly close. They can handle 20A with problems, but at 30A they get too hot.
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I forgot to mount the temperature sensor on one of the batteries.
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Conclusion
This is a nice high current battery and the slightly large size compare to a 18650 can be seen on the improved performance.
This battery is mostly for people that needs well above 10A, for lower currents look at a 18650.
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