Efest IMR18500 1000mAh (Purple) 2016
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Official specifications:
- Model: 18500 High Drain
- 15A Discharge
- Capacity: 1000mah
- Material: Li-Mn
- Flat Top
- Size:18.39(D)*49.79(L)mm
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These batteries are rated for high current and low capacity, but something is wrong. They have fairly high capacity and cannot deliver high current.
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The discharge curve looks good, tracking is just about perfect and the cell has nearly double the rated capacity. The cells can handle 7A, but neither 10A or 15A
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At 7A the cell heat up, but nothing serious.
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At 10A the cell do not have time to heat.
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Conclusion
The batteries looks good for high capacity 18500 cells, but they are not high current cells.
Efest must have made a mistake when wrapping these cells.
Notes and links
The batteries was supplied by Efest for review.
As an extra test I did a 1A cycle on my calibrated SkyRC MC3000 and it showed 1906mAh.
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