Test/Review of Keeppower 18650 3500mAh (Black) 2015

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HKJ
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Test/Review of Keeppower 18650 3500mAh (Black) 2015

Keeppower 18650 3500mAh (Black) 2015

DSC_1147

Official specifications:

  • Capacity min.: 3400mAh
  • Capacity typ.: 3500mAh
  • Nominal voltage: 3.70V
  • Charge voltage: 4.20+/-0.05V
  • Standard discharge cut-off voltage: 2.50V
  • Standard charge current: 1000mA
  • Charge termination current: 50mA
  • Standard discharge current: 3400mA
  • Max. continuous discharge current: 8A


Keeppower%2018650%203500mAh%20(Black)%202015-info

This is a protected high capacity cell.

DSC_1145 DSC_1146

DSC_1148 DSC_1149

DSC_1150
DSC_1151

Keeppower%2018650%203500mAh%20(Black)%202015-Capacity

Very nice curves with good tracking. On one of the cells the overload protection trips during a 7A discharge.
My result is below rated capacity, some of the reason is probably because I terminate charge a bit early (100mA instead of 50mA) and do not discharge to 2.5 volt, only to 2.8 volt.

Keeppower%2018650%203500mAh%20(Black)%202015-CapacityTimeHours

Keeppower%2018650%203500mAh%20(Black)%202015-CapacityTime

Keeppower%2018650%203500mAh%20(Black)%202015-Energy

Keeppower%2018650%203500mAh%20(Black)%202015-PowerLoadTime

Keeppower%2018650%203500mAh%20(Black)%202015-TripCurrent

Keeppower%2018650%203500mAh%20(Black)%202015-Charge



Conclusion

This cell has about the same capacity as a 3400mAh cell, but handles load a bit better.
I will rate this cell very good.



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 18650 and other batteries

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

Edited by: HKJ on 10/06/2015 - 04:33
akhyar
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Thanks for your review HKJ.
Excellent, as always
I’ve this battery incoming from Banggood, so can’t wait to give it a go.

mongoose
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Thanks for the review hkj. Why would the batteries protection trip near the end of the discharge, and not straight away, any reasonable reason?

homer

HKJ
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mongoose wrote:
Thanks for the review hkj. Why would the batteries protection trip near the end of the discharge, and not straight away, any reasonable reason?

Heat. The trip level will change with temperature.

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

BigLEO
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thanks for the nice review HKJ

i came across this tool….
http://lygte-info.dk/review/batteries2012/Common18650comparator.php

if you do comparisons:
KP 3500mah VS 3600mah
KP 3400mah VS 3500mah

very bit of capacity improvement but there is improvement Smile

malkoff junkie
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Thanks to HKJ.
I am in the UK , but where can these be purchased from I did try a illumn but it seems they’ve been broken into a while ago so I think that’s quite slow at the moment right?.

It’s costing me USD$41.00 shipped to london.
Any place better?.

by the way these will be used in a HDS Clicky.
Thanks.

Malkoff !

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you may get some helps at https://www.akkuteile.de/

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elzetta_dy wrote:
Thanks to HKJ.
I am in the UK , but where can these be purchased from I did try a illumn but it seems they’ve been broken into a while ago so I think that’s quite slow at the moment right?.

It’s costing me USD$41.00 shipped to london.
Any place better?.

by the way these will be used in a HDS Clicky.
Thanks.

The Keeppower is a rewrap of this:
https://www.fasttech.com/product/2399300

superjing
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hi, as you use this battery in flashlight, a protected Li-ion battery is always recommended.
i donnot recommend you use unprotected Sanyo ncr18650ga Smile
fyi:
http://lygte-info.dk/info/isMyBatteryProtected%20UK.html

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bwl123 wrote:
The Keeppower is a rewrap of this: https://www.fasttech.com/product/2399300[/quote]

Is this true?  The button top looks different. If not, which cell is used in this KeepPower?

EDIT - It looks to be the LG 18650MJ1, is this correct?

-Garry

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garrybunk wrote:

bwl123 wrote:
The Keeppower is a rewrap of this: https://www.fasttech.com/product/2399300

Is this true?  The button top looks different. If not, which cell is used in this KeepPower?

EDIT – It looks to be the LG 18650MJ1, is this correct?

-Garry

The button-top on the Keeppower definitely looks different as the stock Sanyo GA and LG MJ1 are flat-top batteries straight from the factories.

As the spec sheet of this battery at Keeppower website listed this cell is Made in Japan, we can assumed it is the Sanyo GA
Keeppower 3500

Normally Keeppower will list the cell’s country of manufacturer for their batteries, for eg. they have 2 types of protected 3200 batteries, one is listed as cell Made in Japan (Panasonic BE) while another listed as cell Made in Korea (LG E1 4.35v).

Their IMR 3200, which is listed as cell Made in Japan is most probably Panasonic BD since it has continous discharge current of 10A

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Thanks for the info! 

-Garry

My Bike Lights Thread, Optics (TIR) Comparison Beamshots, Diffusion Techniques

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SubLGT
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The protected EVVA 18650 3500mAh battery (with the GA cell) has very similar discharge curves (on the HKJ Comparator) to this Keeppower, at loads of 3A and under. But at loads above that, the EVVA has noticeably less voltage sag, presumably because of a higher current protection circuit.

vestureofblood
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HKJ, I bout a west mountain Radio CBA IV to test cells with. When I do I keep getting these little “squiggles” at the very end of each line of the the chart. Its like the machine lets up off the test and then starts again leaving that little ripple at the end. Do you know how I can eliminate that?.

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HKJ
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vestureofblood wrote:
HKJ, I bout a west mountain Radio CBA IV to test cells with. When I do I keep getting these little “squiggles” at the very end of each line of the the chart. Its like the machine lets up off the test and then starts again leaving that little ripple at the end. Do you know how I can eliminate that?.

I did use a CBA for my first battery tests (2010 & 2011), but do not remember any squiggles. If the CBA continues to record after the current is stopped you will get a raising voltage, is that it?

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

vestureofblood
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Here is what it looks like. These were nimh 1.2v cells

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fluke
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I am very far from knowing much on testing, is that not the battery voltage rising as HKJ said?

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fluke wrote:

I am very far from knowing much on testing, is that not the battery voltage rising as HKJ said?

Yes. What I need to know is if its possible to squash that. There is a setting I found that says something to the effect of “rebound voltage” (don’t have it in front of me at the moment) but regardless of what I set that to this still happens.

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It looks like you may be out of range. 0.6V is rather low and the load may do strange things at that voltage (That is said without checking the specifications).
When testing significantly below 1V you have to know what you are doing, a lot of test equipment may fail or give wrong results. There are a couple of reasons for that.

My website with reviews of many chargers and batteries (More than 1000): https://lygte-info.dk/

vestureofblood
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HKJ wrote:
It looks like you may be out of range. 0.6V is rather low and the load may do strange things at that voltage (That is said without checking the specifications). When testing significantly below 1V you have to know what you are doing, a lot of test equipment may fail or give wrong results. There are a couple of reasons for that.

I will try running the test at 0.7-0.8 and see if that helps Smile

In Him (Jesus Christ) was life; and the life was the light of men. And the light shineth in darkness; and the darkness comprehended it not.
http://asflashlights.com/ Everyday Carry Flashlights, plus Upgrades for Maglite.