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

HKJ · 2019-08-17T15:05:49.000Z

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

Barkuti · 2019-08-17T15:29:42.000Z

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.

Superstocker · 2019-08-18T23:44:16.000Z

Thanks HKJ!

mrheosuper · 2019-08-19T02:51:57.000Z

Barkuti:

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.

or maybe NCR18650B, a quite common choice

Barkuti · 2019-08-19T03:20:44.000Z

mrheosuper:

…

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.

SubLGT · 2019-10-20T22:44:06.000Z

Barkuti:

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

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.