Efest IMR26650 4200mAh (Purple) 2016
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Official specifications:
- Rated capacity: 4200mAh
- Rated voltage: 3.7V
- Max continuous discharge current: 40A
- Pulse discharge current: 60A
- Lifetime: 500 cycles to 60%
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A 26650 cell with current rating.
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The discharge curves tracks fairly well and capacity is nearly constant with load.
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The battery gets very warm at 30A.
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Conclusion
The battery has good performance, but I doubt the 40A rating.
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