Test/review of Keeppower 18650 3600mAh P1836J (Black) 2019

Keeppower 18650 3600mAh P1836J (Black) 2019







Official specifications:

  • Capacity min.: 3450mAh

  • Capacity typ.: 3550mAh

  • Nominal voltage: 3.70V

  • Charge voltage: 4.20+/-0.05V

  • Standard discharge cut-off voltage: 2.50V

  • Standard charge current: 1800mA

  • Charge termination current: 50mA

  • Max. continuous discharge current: 8A



This is a protected high capacity cell from Keeppower.










The discharge curves tracks nicely and the protection kicks in when drawing too much current.





















Conclusion

This is some of the highest capacity 18650 batteries on the market, but they have about the same capacity as 3500mAh rated batteries.
It is a good cell.



Notes and links

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
Graphical comparison to 18650 and other batteries
Table with all tested LiIon batteries

Totally looks like an overrated Samsung 35E rewrap with protection circuitry.

I see the label says “Cell & IC made in Japan”, for which the former I find I bit dubious.

Thanks.

Thanks HKJ!

or maybe NCR18650B, a quite common choice

Too low capacity, the NCR18650B barely does 3300mAh without a protection circuit, much less with one attached.

The shape of the discharge curve does not match with that of an NCR18650B. It matches accurately with the one of a Samsung 35E.

If HKJ were to dismantle cell rewraps some nice information we would obtain.

Over at Illumn.com (who is the North American distributor for Keeppower batteries) the cell for #P1836J is listed as the Panasonic NCR18650G:
https://www.illumn.com/batteries-chargers-and-powerpax-carriers/batteries/18650-keeppower-3600mah-panasonic-ncr18650g-protected-button-top.html

But when I look at the 1A and 5A discharge curves for the P1836J and the Panasonic G, they do not look very similar.