UltraFire SZ18650 9900mAh (Yellow)
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Official specifications:
- Capacity: 9900mAH
- Voltage: 3.7V
- Size: 65mm x 18mm
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The latest battery scam from China.
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I tried 3 cells, there were surprisingly well matches, but below* rated capacity and not able to deliver much current.
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They do stay cool.
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Also at "high" current.
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Conclusion
Any brand name cell is cheap compared to these, when looking at $/mAh. For cheap cells look for brand name 2600mAh cells, never something above 3500mAh.
The rating is, of course, bad
Notes and links
*"Very much below" is probably more correct.
Disassembly of UltraFire 9900mAh 18650 battery
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