Soshine 18650 LiFePO4 1800mAh (Black)
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Official specifications:
- Nominal voltage: 3.2 V
- Nominal capacity: 1800 mAh
- Core cell weight: 40 g
- Size: D18.1*H68.5mm
- Continuous Discharge: 5A / Pulse: 3A (Pulse current lower than continuous current?)
- Typical fast charge current: 3.6A to 3.6V CC/CV
- Fast charge time: 40 minutes
- Cycle life at 10C discharge, 100% DOD: over 1,000 cycles (Nice long lifetime, but difficult to test because protection limits discharge to 2C)
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Soshine has a series of LiFePO4 cells, this is their 18650 sized one.
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This is a typical LiFePO4 discharge curve and it looks good. As can be seen the voltage is nearly flat during discharge and then drops very fast when the battery is empty.
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LiFePO4 has a significant voltage drop when charging stops.
Conclusion
The cells looks like good LiFePO4 cells, but I wonder about the fairly low current overload protection.
There is also the usual limited capacity with this chemistry, it has less than half the energy of a modern 4.2 volt LiIon cell.
Notes and links
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