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IMR 26650 3700mAH High Drain Cells

J

jasonck08

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Hi guys, I managed to get a hold of some of these "hard to find" cells. These IMR 26650's are monsters and are great for high and low currents (Flashlights, lasers etc). They are the best cells out there on the market!

These are grade A cells, and are UL listed. Please be aware that many of the cells you see coming from overseas are fake or reject cells. As some may be aware, the 4000mAH MNKE cells are no longer being produced. These are 3700mAH cell although slightly lower in capacity (than the 4000's), but feature slightly low internal resistance and improved cycle life! These are the best high drain 26650's you can buy on the market! Limited quantities available!

Specs:

Cell type: IMR-26650
Capacity: 3700mAH ± 100mAH
Chemistry: LiMn2O4 (IMR)
Recommended charge current: 1C (3.5A)
Max charge current: 6.5A
Rated cycle life: 800 cycles @ 10A discharge
Normal discharge current: 10A
Max continuous discharge current: 20A
Max pulse discharge current (10s): 60A
Charge voltage: 4.20 ± 0.05V
Discharge Cutoff voltage: 2.50v
Nominal voltage @ .2C: 3.8v
Cell size and weight: 26.2mm x 66.5mm, 93g
Factory raised positive contact: easily makes contact in series!

IMR26650logo.jpg


These can be ordered through my site. MNKE IMR 26650 3700mAH

Any questions, please let me know. Thanks! :)
 





DTR said:
I am 99% positive this is the same cell and a bit cheaper on batteryspace. They always rewraped the MNKE 4000mAh units when they were available and the specs seem right. They also do all their own testing and list their results as the battery specs.:beer:

Powerizer New Generation High Power Lithium (LiNiMnCo) 26650 Rechargeable Cell: 3.6V 3600mAh

Here is a few of these cells that were tested over @ BLF.

26650 Batteries | BudgetLightForum.com
Click to expand...

Hi, I am 99% sure these are not the same. In the past battery space was selling unbranded old stock MNKE cells, but these are NOT MNKE cells.

Several reasons why:

1) Look at the positive end of the cell, it is not the same.

2) The Battery Space ones are not LiMn but are LiNiMnCo. This means they also contain Nickel and Cobalt. Cobalt being the more dangerous ingredient.

3) Battery spaces cells have a 3.65v nominal voltage. The ones I'm selling are 3.8v.

Also worth mentioning is battery spaces charges over $9 just for shipping a single cell. I charge about $3.
 
Did not notice you were the ones selling them. I thought you meant you bought them from that site.:o

I did not notice the chemistry difference so they must be different but they looked pretty close to me and I know they use to do that with the old ones. The rating differences could pretty easily have been from not using the manufacturer ratings but the testing they say they do them selves.

$3 is pretty good for a single cell. Batteryspace is actually $5.35 up to 5 cells and $12 for 6-20 cells. I have always bought in bulk from them so I have not noticed the per cell price.
 
DTR said:
Did not notice you were the ones selling them. I thought you meant you bought them from that site.:o

I did not notice the chemistry difference so they must be different but they looked pretty close to me and I know they use to do that with the old ones. The rating differences could pretty easily have been from not using the manufacturer ratings but the testing they say they do them selves.

$3 is pretty good for a single cell. Batteryspace is actually $5.35 up to 5 cells and $12 for 6-20 cells. I have always bought in bulk from them so I have not noticed the per cell price.
Click to expand...

Not quite sure how you are getting those shipping rates. I go to the site add a cell to cart, put in my zip code and it shows UPS Ground $9.09 for 1 cell.

Secondly, yes these cells are different. The ones the battery space currently sells have no long term track record. How will they hold up? No one knows.

MNKE has been around for a while. Some of their engineers are from MOLI, a company well known for making high current IMR 26700's and 18650 cells. MNKE is more well known, and people have been using these cells for years.

Lastly, I too have my own testing equipment. I just discharged a random sample and got almost exactly 3700mAH. I've run probably 20-30 tests on MNKE cells over the past 2-3 years. I can assure you the nominal voltage is higher on these than the battery spaces cells. True IMR (LiMn) cells are going to be safer than an IMR / LiNiCO hybrid cell. With that said, I think these cells are worth the few bucks more vs the battery space ones.
 
You have to switch to the USPS shipping from the UPS. There is a drop down menu.;)

What does the higher nominal voltage do for the cell? Can one cell be discharged to a lower voltage or will one hold a higher voltage longer?
 
DTR said:
You have to switch to the USPS shipping from the UPS. There is a drop down menu.;)

What does the higher nominal voltage do for the cell? Can one cell be discharged to a lower voltage or will one hold a higher voltage longer?
Click to expand...

Ahhh I didn't see the USPS option, it just defaults to the more expensive UPS.

Anyways, a higher nominal voltage basically just means the average voltage is higher throughout the discharge of the cell. The industry standard for determining nominal voltage and capacity is 0.2C, or discharging the cell at 1/5th of its rated capacity. The nominal voltage of a cell is determined by the cell chemistry and the internal resistance. For higher power LED's and bulbs for example, that could translate into higher brightness vs a lower nominal voltage cell. And yes, a higher nominal voltage cell is going to provide a higher voltage over a longer period of time. It also means overall the capacity of the cell in Watt hours is going to be higher.

For example: 3.8v x 3.7AH would mean 14.06 Whrs.

Or for the battery space cell: 3.65 x 3.6AH = 13.14 Whrs.
 
What is the internal resistance?
Or how much does the voltage drop at like 5A output current?
 
justinjja said:
What is the internal resistance?
Or how much does the voltage drop at like 5A output current?
Click to expand...

I don't have a battery AC resistance meter (hope to get one in the future), but it should be <20 mili Ohms according to MNKE.
 
Greetings,

Please help me out, as I had always thought the IMR's were 65mm and not the 65.2mm ?
I have a laser I am currently using a spacer and an 18650 as those I have are 65mm. The extra length on those other batteries will not allow me to screw on the end cap. So far the panasonic 3100mah 18650's are the best I am able to use. Are there any 65mm length imr 26650's in existence ?

Moe
 
justinjja said:
How about a DMM and a 1ohm resistor?

What is the battery voltage when powering a 1 ohm resistor?

See this thread for measuring internal resistance:
http://laserpointerforums.com/f67/h...es-how-measure-internal-resistance-57576.html
Click to expand...

Yea, I'm not going to measure IR using that method. Far to sketchy for me... Very inaccurate compared to commercial IR machines that use an AC pulse measurement method. All I have on hand are 1/4W resistors. I plan to buy a commercial IR bench top meter in the future... I can use my computerized battery analyzer to graph some of these cells if people are interested, let me know the current you want to see them graphed at.

offroadfreak8582 said:
Can somebody buy these for me and shop them to the netherlands? They dont ship overseas :(
Click to expand...

As of 5/15/2012 it is illegal to ship Li-ion batteries through the US Post office! :( I may be able to have a business partner send some from Taiwan in the future, but still working out the details...
 
Last edited:
jasonck08 said:
As of 5/15/2012 it is illegal to ship Li-ion batteries through the US Post office! :( I may be able to have a business partner send some from Taiwan in the future, but still working out the details...
Click to expand...

I second that decission :beer: you are really limiting yourself now. I had to order from another site now:thinking:

greetings,,
 
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