(fake?) MNKE IMR 26650 4000mAh test

[jirik_cz]

Just finished testing of MNKE IMR 26650 4000mAh batteries sold here in the marketplace.

They are advertised as "IMR LiMN" so some may think that they are high-current capable. Unfortunately they doesn't seem to be really high-current li-ion cells. Based on the performance I would say that they are just common LiCoO cells.

edit: Please note, that batteries sold by gigainternational.com are probably fake MNKE cells and not the real ones...

Comparison with top 18650 li-ion batteries and unprotected Xtar D li-ion.

 

[jasonck08]

Re: MNKE IMR 26650 4000mAh test

Terrible performance to be honest!

You bought these from gigainternational right?

I talked to the company MNKE and they do make 4000mah 26650's, but they do not make 18650 2400mAH IMR cells. Highest capacity IMR 18650's they make are 1500mAH. They also don't make 16340's.

I have a feeling that these are fake cells and are not made by MNKE.

The discharge chart from MNKE shows excellent performance even under heavy discharge of 10-20A.

 

[45/70]

Re: MNKE IMR 26650 4000mAh test

The graphs do look a bit strange. If I were to guess, without having already been told that they were LiMn cells, I'd say they were LiFePO4 cells, although LiFe cells usually have a much flatter discharge curve than those cells.

Dave

 

[Mjolnir]

Re: MNKE IMR 26650 4000mAh test

There is no way those are IMR cells. The batteryspace IMR 2650s have similar performance under 4 amps as these cells under 1 amp. However, the batteryspace cells are actually 4000 Mah, while these appear to be much less even under .5 amp load.

I see no reason to buy these, as they also cost $4 a piece more than the batteryspace cells, and fall far behind in performance.

 

[45/70]

Re: MNKE IMR 26650 4000mAh test

Heh, after looking at the graphs again, I see the voltage is way to high for LiFe cells at the lower current levels. My mistake. I think you guys are right, they are just "not very good" LiCo's.

Dave

 

[jirik_cz]

Re: MNKE IMR 26650 4000mAh test

Terrible performance to be honest!

You bought these from gigainternational right?

but they do not make 18650 2400mAH IMR cells. Highest capacity IMR 18650's they make are 1500mAH. They also don't make 16340's.

I have a feeling that these are fake cells and are not made by MNKE.

Yes, they are from gigainternational.

Currently I'm working on tests of their "IMR" 18650 and RCR123 cells. They doesn't seem to be high-current either.

 

[jasonck08]

Re: MNKE IMR 26650 4000mAh test

What are you using to test the capacity? Doesn't look like a CBA that most people use.

Also, when doing high current discharges check the voltage at the battery and compare it with the voltage that the software is reporting. You might have some considerable voltage drop at high current tests.

Before a beefed up my discharging rig I was getting like .4v drop @ 5A which is considerable.

 

[jirik_cz]

Re: MNKE IMR 26650 4000mAh test

I'm using CBA as everyone else Only export data to Excel to make nicer graphs.

I measured 0.05V drop at 10A discharge on the cables, so it is not very significant.

 

[jasonck08]

Re: MNKE IMR 26650 4000mAh test

If these are really IMR cells then you are suppose to discharge down to 2.5v ususally, although I don't think the capacity will increase by much.

 

[Battery Guy]

Re: MNKE IMR 26650 4000mAh test

What is the "CBA" equipment that people are using to do these discharge tests at home?

Cheers,
Battery Guy

 

[mvyrmnd]

Re: MNKE IMR 26650 4000mAh test

Bugger! I just bought 3 of these to use in a hotwire, and was expecting to draw 8A from them.

This is very disappointing.

 

[jirik_cz]

Re: MNKE IMR 26650 4000mAh test

What is the "CBA" equipment that people are using to do these discharge tests at home?

Cheers,
Battery Guy

Computerized battery analyzer.

 

[45/70]

Re: MNKE IMR 26650 4000mAh test

What is the "CBA" equipment that people are using to do these discharge tests at home?

Cheers,
Battery Guy

Computerized battery analyzer.

It's a highly overpriced (for what it is anyway) Computer Battery Analyzer that some of us (like myself) felt we needed just as much as a new hole in our head.

Mine's a "CBA II". There is now an updated "CBA III". They're interesting to play with though. I use mine quite a bit. Not super accurate, but plenty good enough for comparative analysis of small packs and cells.

Dave

 

[jasonck08]

Re: MNKE IMR 26650 4000mAh test

I'm interested to see your 18650 and 16340 tests.

 

[Stereodude]

Re: MNKE IMR 26650 4000mAh test

These aren't the same as the Batteryspace LiMnNi 4000mAh 26650's are they?

 

[jasonck08]

Re: MNKE IMR 26650 4000mAh test

These aren't the same as the Batteryspace LiMnNi 4000mAh 26650's are they?

No these are MNKE brand or maybe fake MNKE brand. Batteryspaces are made by another company and are actually properly rated @ 4000mah.

 

[ptolemy]

Re: MNKE IMR 26650 4000mAh test

Wow, that's just terrible...One would think if someone is paying $15 for a cell (a quality 26650 is worth $10-15, IMO), there would be discharge graphs available prior the fact

 

[QtrHorse]

Re: MNKE IMR 26650 4000mAh test

I was told the the blue lable MNKE IMR 26650 batteries were of a lesser quality than the orange label MNKE batteries. I have some of the orange label MNKE batteries and will have them tested as well.

 

[jasonck08]

Re: MNKE IMR 26650 4000mAh test

I was told the the blue lable MNKE IMR 26650 batteries were of a lesser quality than the orange label MNKE batteries. I have some of the orange label MNKE batteries and will have them tested as well.

I think these are fakes. I talked to a guy from MNKE and he said they don't make 2400mah IMR 18650's. And they don't make ANY 16340 IMR's. So those two cells at least are fakes. Don't know about the 26650's though.

 

[ptolemy]

Re: MNKE IMR 26650 4000mAh test

I think these are fakes. I talked to a guy from MNKE and he said they don't make 2400mah IMR 18650's. And they don't make ANY 16340 IMR's. So those two cells at least are fakes. Don't know about the 26650's though.

Where are you getting 2400mah imr 18650's from?

i dont thinK MNKE makes these. It's a typical chinese oem that can have any label on them if you buy in bulk

whatever mnke company is, they probably bought 1000 units and asked oem make them MNKE...

and you should know better than to believe manufacturer/reseller than a comparison test here