Test / Review: Keeppower IMR18650 2250mA (Black)

Keeppower IMR18650 2250mA (Black)



This battery is a high current battery without any protection!

Official specifications:

  • IMR18650 2250mAh Protected Rechargeable Battery
  • Cell: Panasonic CGR18650CH 2250mAh
  • Min Capacity: 2150mAh
  • Typical Capacity: 2250mAh
  • Normal Voltage: 3.6V
  • Quality Lithium Ion rechargeable cell
  • 4.2 volts max voltage and 3.6 volts nominal voltage




Because this battery is without a protection PCB, but with an added button top the size is only slightly longer than the official 65 mm long.


















This battery does not have any current protection and the curve only shows voltage under load. Doing 5 tests (Each takes about 100 seconds when running up to 15 ampere) did use most of the capacity in the cell. This can be seen on the last part of the last test trace.





Conclusion

The battery uses a good cell, making it a fairly safe cell, but remember it is unprotected and must not be over discharged. For uses with high current this is a very good battery and it can deliver more capacity at a higher voltage than 3100 mAh cells at high current.



Notes and links

Keeppower is a OEM manufacturer, i.e. many of the batteries they produce is sold with other names on them.

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

So the battery is advertised as protected but isn't or am I misunderstanding something?

That was a typo from me, I will go fix it now.

A typo, scary :wink:
As for the cell - I’m impressed :open_mouth: 10A discharge with excellent result! Wow :crown:

Because they are missing from the website I had to type the specifications from a piece of paper and I did use copy/paste (oops).

Thanks very much for the excellent review! Frontpage’d and Sticky’d.

Thanks for another excellent review! I’m surprised it does even better than the AW IMR 18650.

But when you say “it can deliver more capacity at a higher voltage than 3100 mAh cells at high current”, do you mean at discharge currents higher than 7.0A? I only ask because I haven’t seen any of your tests for 3100mAh cells at discharge currents above 5A.

Try comparing the 5A trace between a 2900/3100mAh and this battery:

For the first 2000mAh it has the highest voltage. I do not have any curves for higher currents, but the 2250 would probably just get even better and the 3100.

The next think is lifetime, at these current the 2900/3100mAh will probably not last that many cycles, where the 2250 is designed for this load.

Ah I didn’t look at it that way. Thanks for clarifying!

Great review - very informative, as always.

Is anyone aware of a retailer for these, and other Keeppower cells?

I read that the chemistry of IMR cells is safer than other common Li-ion cells, but what is the general opinion of using IMR cells (which are safer but unprotected) in multi-cells flashlight?

What about risk of unbalancing during discharge, and possible risk of one cells getting discharged before the others and reverse charging? (this would happen when cells are in series)

And what about multi-cells in parallel (in a Skyray King for example) ie there a risk of cells damaging eachother when resting unused due to parallel setup, and cells trying to balance eachother to the other and slowly selfdischarging in the meantime? (well, this would happen with any kind of cells, I think...)

I would like to buy some IMR cells but as I would use them in many multy cells lights I need to understand them a bit more...

The chemistry is safer, but the cell does not like to be over discharged, it does not make the cell explode, but the cell looses capacity. Because IMR are sold without protection you have to be very careful not to over discharge them.

great review ,from where can we buy them?

Depends on what you want to use it for, the discharge curves are exactly the same, but a standard Panasonic has a flat top, this one has a button top.