Keeppower 26650 4000mAh (Black) 2014



Official specifications:

• Product Name: Keeppower Protected 26650 3.7V 4000mAh
• Supplier: Keeppower Technology Co., Limited
• Cell: China 26650 4000mAh
• Capacity: Min. 3920mAh; Normal: 4000mAhDischarge:0.2CmA
• Normal Voltage: 3.70V
• Stanard Charge voltage: 4.20V
• Standard Charge current: 2000mA
• Charge Time(Std.): 3 hours
• Standard Discharge Cut-off Voltage: 2.750V
• Standard Discharge current: 800mA
• Standard Discharge cut off current: 30mA
• PCB Protection trip current: Above 10A
• Storage Temperature:-20°C~+60°C Less than 1 month, -20°C~+45°C Less than 3 months
• WeightMax 95g
• Size(L)71.10mm*(D)26.50mm

The battery has good performance, but the over current protection does not work as expected.










The battery does easily live up to its rated 4000mAh and the two batteries has good tracking up to 7A.











The protection does not trip, I asked Keeppower about it and they told me the protection was at around 20A. This is way to high for this battery.
The over discharge and over charge protection is still supposed to work correctly.





Conclusion

This battery has good performance up to 7A, but the missing over current protection does reduce the safety some.



Notes and links

The battery 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