Test/review of Sony US21700VTC6A 4000mAh (Green)

[size=+3]Sony US21700VTC6A 4000mAh (Green)[/size]



Official specifications:

• Size: 21700
• Nominal Capacity: 4000mAh
• Continuous Discharge Rating: 30A (40A with 80° Deg. C temperature cut)
• Nominal Voltage: 3.6v

This is a 21700 high current cell and it is not really from Sony anymore, Murata has bought the LiIon battery business from Sony.











The two batteries are very well matched, but at 30A they have problems with heat.





My thermosensor ran out of batteries and did not stop discharging of the A battery, instead the internal fuse in the battery blow.















[size=+3]Conclusion[/size]

This is a good battery and can easily deliver 20A, but at higher current it best to have a temperature cut-out.



[size=+3]Notes and links[/size]

The batteries was supplied by Vapcell 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
Graphical comparison to 18650 and other batteries
Table with all tested LiIon batteries

Thanks! Do you suspect Murata is using Sony's tooling and technology to make current cells, or are they just buying the SONY name and making them elsewhere?

Chris

ChrisGarrett said:

Thanks! Do you suspect Murata is using Sony's tolling and technology to make current cells, or are they just buying the SONY name and making them elsewhere?

Click to expand...

They got the technology, not the name. But maybe the right to use the name for a limited period, this cell do not have "Sony" on it, but the look is similar to the other VTC cells, including the warning.