Keeppower 18650 2800mAh (Black)
Official specifications:
- 18650 280mAh Protected Rechargeable Battery
- Min Capacity: 2700mAh
- Typical Capacity: 2800mAh
- Normal Voltage: 3.7V
- Quality Lithium Ion rechargeable cell
- In Built Safety Circuitry
- Maximum capacity and reliability
- High Discharge Rate (Max 2C)
- Protection Circuit (Against overcharge, over discharge, over current and short-circuit.)
- 4.2 volts max voltage and 3.6-3.7 volts nominal voltage
This battery is not the usual 4.2 volt charging, but needs 4.3 volt charging, i.e. a special charger must be used (Some hobby chargers can be adjusted for it).
The capacity is slightly below 2800mAh, but very constant at different loads. The battery has a high voltage, but not higher than the best 4.2 volt batteries. Where it is better is runtime at high voltage.
Test with 4.2 volt charging
It is possible and perfectly safe to use this battery with 4.2 volt, but it will have less capacity.
When only charging to 4.2 volt the battery looses about 200mAh in capacity.
Conclusion
That battery uses a good cell and does what is supposed to do, this makes it a very good battery.
But the requirement for a special charger to get the full benefit of the battery, does reduce the usefulness of it. Using it with a 4.2 volt charger negates any benefit of the higher voltage and capacity.
Notes and links
Keeppower is a OEM manufacturer, i.e. many of the batteries they produce is sold with other names on them.
The batteries was supplied by Keeppower for 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