Efest IMR18650 2500mAh (Purple) 2016
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Official specifications:
- Typical Capacity: 2500 mAh
- Nominal Voltage: 3.7V
- Discharge End Voltage: 3.0V
- Standard Charging Current: 1.5A
- Charging Voltage: 4.20+-0.05V
- Max Pulse Discharging Current: 35A
- Dimensions: 65.11mm (L) x 18.44 mm (D)
- Weight: 46g
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A 2500mAh battery with a fairly high current rating.
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The discharge curves look very good, they tracks perfectly and capacity is nearly constant.
The battery got warm at the higher current and I had to stop.
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I stopped this discharge a bit early due to temperature.
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For now I am running with a fairly low maximum temperature (This trace here melted one battery holder).
Remember the traces are temperature increase, i.e. the actual battery temperature is 25-30°C higher.
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Only B battery is valid, the holder for A is melted.
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Only B battery is valid, the holder for A is melted.
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Conclusion
The battery has good performance, but gets warm at 30A (Not a big surprise).
Notes and links
The batteries was supplied by Efest for a 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