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

[SIZE=+3]Keeppower 18650 3500mAh (Black) 2015[/SIZE]



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

This is a protected high capacity cell.










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.















[SIZE=+3]Conclusion[/SIZE]

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



[SIZE=+3]Notes and links[/SIZE]

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

What is your source for the above "official specifications"? It would be helpful to include a link to such sources in your reviews. For example, it is not clear what the source is for "Standard discharge current: 3400mA" (or even what that denotes lacking any further context)

Gauss163 said:

What is your source for the above "official specifications"? It would be helpful to include a link to such sources in your reviews. For example, it is not clear what the source is for "Standard discharge current: 3400mA" (or even what that denotes lacking any further context)

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Usual my specifications are from the dealers, manufacturers website or a datasheet.
In this case Keeppower supplied my with the specifications in a spreadsheet and they are using 1C as standard discharge current for many of their cells.

Gauss163 said:

What is your source for the above "official specifications"? It would be helpful to include a link to such sources in your reviews. For example, it is not clear what the source is for "Standard discharge current: 3400mA" (or even what that denotes lacking any further context)

Click to expand...

people have been guessing that the Japan cell inside iirc be the Sanyo NCR18650GA.
look for the word "Datasheet" found on NKON's sales page.

kreisl said:

the Japan cell inside iirc is the Sanyo NCR18650GA, click on the word "Datasheet" found on NKON's sales page.

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Very good cell! I'm currently using these, but looking for the Keeppower unprotected, buttontop version since they may be cheaper than the naked cells I'm buying now. Can't find them anywhere.

Nice review. I've been using this battery lately, when I don't need a high drain battery, and have been very happy with it.

I am very pleased with the ten Keeppower 3400mAh batteries.

kreisl said:

the Japan cell inside iirc is the Sanyo NCR18650GA, click on the word "Datasheet" found on NKON's sales page.

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That is a guess and may not be correct.

Many vendors I see say "Keeppower P1835J Genuine SANYO / PANASONIC NCR18650GA Cell & Integrated Circuit (IC) made in Japan."

So it's basically "do you trust them?"

markr6 said:

So it's basically "do you trust them?"

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According to the information I got from Keeppower it is not correct, but it is a cell from one of the good manufacturers (Keeppower may have a typo in the information I got).

HKJ said:

That is a guess and may not be correct.

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You measured 3,286mAh at the lowest discharge rate. That's way below 3500mAh. So i don't believe that its got GENUINE NCR18650GA inside.

light-wolff opened the wrapper of Olight cell to verify if its Sanyo NCR18650GA.
you've got 2 FREE samples. if you open 1 wrapper, you would still have 1 unopened battery. that's good enough for me.

If i got 2 FREE Keeppower batteries for review, i'd cut open 1 battery after the tests, no problem. That's the interesting part of the review imho.

This is why tests by HKJ and others are so valuable and needed. Until there is better documentation and battery standards being available, we will always be in a 'buyer beware' situation.

HKJ said:

According to the information I got from Keeppower it is not correct, but it is a cell from one of the good manufacturers (Keeppower may have a typo in the information I got).

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So Keeppower sent you, the reviewer, the information but you don't want to share it with your readers?

May I ask why?

I appreciate this and your other reviews but this is need-to-know information.

kreisl said:

You measured 3,286mAh at the lowest discharge rate. That's way below 3500mAh. So i don't believe that its got GENUINE NCR18650GA inside.

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A little low, but still sounds about right. Cells won't always hit the mark right on. Some do, so go over, but then there's other variables at play, even bad/good luck.

NCR18650GA
-Rated Capacity 3300mAh (typo? should be 3500?)
-Capacity (Minimum) 3350mAh
-Capacity (Typical) 3450mAh

hatman said:

So Keeppower sent you, the reviewer, the information but you don't want to share it with your readers?

May I ask why?

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Because Keeppower asked me not to share it.

Where can I purchase these?.
thanks.

neutralwhite said:

Where can I purchase these?.
thanks.

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Illumn.com lists this, at $13.99 USD each:



From what HKJ says above, however, either this is not the Sanyo NCR18650GA, or else this is a different product from the one HKJ tested.

Excellent test review as always. HKJ!

Thanks a lot for your time and effort. :thumbsup:

my BS meter is reading very high in this thread

take note unwrapping it may not be much help because 2015 keeppowers aren't double-wrapped. here's my unwrapping of the NCR-BE:

https://www.youtube.com/watch?v=iYuL47imynM

kreisl said:

You measured 3,286mAh at the lowest discharge rate. That's way below 3500mAh. So i don't believe that its got GENUINE NCR18650GA inside.
.

Click to expand...

well the GA is 3450mah nominal when measured down to 2.5v.