Test/Review of Keeppower 26650 5200mAh (Black) 2014

Keeppower 26650 5200mAh (Black) 2014

Official specifications:

  • KeepPower 26650 3.6V/3.7V 5200mAh Li-ion Rechargeable Battery
  • Min Capacity: 5100mAh
  • Typical Capacity: 5200mAh
  • Normal Voltage: 3.7V
  • Quality Lithium Ion rechargeable cell
  • Maximum Capacity and Reliability
  • 4.2 volts max voltage and 3.6-3.7 volts nominal voltage

26650 batteries are getting higher capacity, this cell sets the record for capacity.

The two cells has very good tracking and capacity does not vary much up to 5A load.

Protection trips at around 9.5A.


Very good capacity and good performance for a high capacity 26650 battery.

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
Compare to other 26650 batteries

Thanks for yet another helpful review HKJ. I see it says IC made in Japan, do you know who makes or where the cell is made?

Finally the 26650 size battery has reached the capacity that fits the large size! Time to get a nice 26650 flashlight :-)

Thanks for another thorough test HKJ !

Thanks HKJ, agree with djozz, the capacity has now reached the point to make up for the larger size and weight over the 18650.

thanks for the review,from where can we order those?

Illumination Supply has them. They have the unprotected version.

Probably Seiko, but I do not know it.


That is the unprotected version.

I was actually asking about the cell inside, sorry for the confusion.

I can’t seem to find them either. I don’t even see them on the keeppower website. Are they not available yet?

Anybody ever get a line on these?

Keeppower has them on their website now.

Keeppower 26650 5200 mAh protected

well keeppower does not make them, so there should be some others on the market somewhere. i assume they’re chinese.
calvin sells them so he knows who makes them.
who makes them, calvin ?

Calvin at Illumn has them now:

Couldn't find these stocked in the uk so opted for the IMR version listed here from a uk seller on ebay, what actually turned up are the ones reviewed here.


I’ve recently searched for a high current 26650 cell and found this very interesting report about the current Keeppower cells (in German, but there are ways to get it translated :wink:

It seems the repackaging Keeppower does with the wrapping and additional metal plates on the positive poles deliveres not the best performance you could get from these cells…
Since I was after a IMR cell I ended up with an order of a MNKE cell at Nkon since even Efest has them inside:

That’s a very nice review, but it appears to be a 26711 rather than a 26650. Good luck shoving three of those up your Yezl Y3.

I wish somebody would apply a more refined chemistry to 26650 cells instead of just always making them longer. Pretty soon they’ll be boasting 6500 mAh, but the cells will be 80 mm long.

He says that, right in the review.