Question regarding P25 fromb Nitecore

Hello! I'm new into flashlights.
Just got a Nitecore P25 .
I see no difference between the High (550lumens) setting and the Turbo (860lumens) setting. Is that normal?
I use a 18650 Ultrafire Li-ion.

Thank you!

" NOTE: Due to the high output nature - a high output 18650 battery is required for optimal output. The battery must be able to provide 3.0+ amps of power - which the "cheap" Ultra/TrustFire 18650 batteries are unable to provide. We recommend EagleTac 18650's for best fit, max output, and runtimes. "

GordoJones88 said:

" NOTE: Due to the high output nature - a high output 18650 battery is required for optimal output. The battery must be able to provide 3.0+ amps of power - which the "cheap" Ultra/TrustFire 18650 batteries are unable to provide. We recommend EagleTac 18650's for best fit, max output, and runtimes. "

Click to expand...

Thanks for the answer , but my 18650 is a Ultrafire ZP 3800 mAh . Isn't that enough?

I think what he's saying here is any Ultrafire 18650 is untrustworthy junk. Possibly dangerous.

I just bought my first 18650 light and went with Eagletacs based on info gleaned from CPF members.

Sent from my SCH-S720C using Tapatalk 2

I think it is a good answer.

OP, have you tried a Nitecore battery? I received good advice on this topic after having gone through a bunch of inexpensive ebay-china 18650 batteries, with about 50% of them utterly dead.

I was advised to consider using Nitecore batteries with Nitecore products as I could never be blamed for using another type battery should the warranty be needed.

I have found the 18650's from Nitecore (both 2300 and 2600 mAh) to be reliable. I have not yet tested a 3100, as they don't seem to be available here in the US just yet, and are quite expensive.

I have a few Nitecore products and am sold on their quality. They are well made (see the video on Facebook of the TM 26, or Patriot's You Tube review) and of solid quality and look forward to getting the P25. The EC 25 is one heck of a little powerhouse, too and a great all purpose, every day type of light, especially with the filter cap.

deniscure said:

Thanks for the answer , but my 18650 is a Ultrafire ZP 3800 mAh . Isn't that enough?

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Inefficient batteries have higher resistance which become apparent at higher outputs. The 3800 mah capacity has nothing to do with how well the battery will run under load. Check around the "Flashlight Electronics - Batteries Inc" subforum where several members have compiled output graphs comparing 18650s. Not all batteries are made equal!

deniscure said:

Thanks for the answer , but my 18650 is a Ultrafire ZP 3800 mAh . Isn't that enough?

Click to expand...

Absorb this concept:

UltraFire = Ultra LIAR.

It DOESN'T have 3800 mah...they are lying to you. It might not even be a new cell, it might be an old laptop cell they rewrapped and sold as new, etc.

As described above, the fake cells (fill-in-the-blank-Fire...) can't flow enough go go juice at the higher amperages to power the light, so the light is running on a "limp mode".

If you get a REAL 3400 mah cell for example, it will run longer than the fake 3800 mah cell, AND be able to handle the flow at the amps needed to fully power the light.


Now, the sad part...in your head, you bought a 3800 mah cell for ~ $7 or so...and you now think that's ~ what a ~ 3400 mah cell should cost.

Real cells are simply more expensive because they are not old used cells, and, they actually HAVE the specs the fake ones pretend to have.

You can get REAL 2600 mah cells that could handle it for not much more than a fake cell, and many of these can handle the amps better than the 2900 and 3100 mah cells, but not better than the 3400 mah cells.

The Eagletac 3400 mah cell recommended to you above in this thread is good, and tends to fit all the 18650 lights I've tried.


Good Luck!

As an aside, it definitely makes no sense to buy a nice light only to put a junk battery in it. If you buy a junk light, then by all means. But like buying all cheap junk (not just flashlights), it ALWAYS backfires in the end - whether it be tomorrow or 3 years from now, you'll eventually wish you had bought the real item. So ultimately not only did you not save money by buying junk, you LOST money because it's now useless junk in the garbage can. Only problem is sometimes the "real" stuff is also junk.

Thank you all for your answers!

When I bought the P25 I also bought a Nitecore 18650 2600mAh battery. Unfortunately they didn't arrive at the same time, so yesterday, being eager to test the Nitecore, I fed it with the cheaper Ultrafire "3600mAh" that came with the standard Chinnesse Ultrafire Q5 Cree Flashlight that I previously got from Ebay 3 months ago for around $15-$20 with this battery included.

Today I got it out and I'm waiting for the Nitecore Li-ion. I'm sure it will perform better from all the info I'm getting from you and I'll come back and give a feedback once I test it.

So I couldn't abstain myself and cut off the cover of my Ultrafire 3800mAh (not 3600, I must have misremembered it) and here's what I found in it:
A white tube in which there was the battery sitting with the blue cover scratched so you couldn't read any specifications. What could this be? Just inattentive assembly, or pure and simple recycling?

Wow, there's the proof right there. Scratching out the specs....LOL.

BTW.....when the nitecore battery comes in, please update us. I'd like to hear about any improvements in performance.

Of course! I can hardly wait myself!

deniscure said:

So I couldn't abstain myself and cut off the cover of my Ultrafire 3800mAh (not 3600, I must have misremembered it) and here's what I found in it:
A white tube in which there was the battery sitting with the blue cover scratched so you couldn't read any specifications. What could this be? Just inattentive assembly, or pure and simple recycling?

Click to expand...

That, my good man, is the LIE EXPOSED.

They took an old cell, scratched off the specs, re-wrapped it...and sold it to you as a new (Higher performance yet) 18650.


UltraFire = Ultra Liar


The mah is not the spec that was the problem in your light not WORKING.....that just relates to run time. It was a lie, but that's another issue.

The problem is that as a cell ages, the internal resistance rises, and it gets harder and harder to get enough amps to support the higher power settings. So an old cell is too weak to give the light the amps it needs.

If you have one of those aged cells with higher internal resistance, and another with different resistance, it generates heat if they are run in series, for example in a multi-celled light...and you can get a fire or even explosion.

This can be very dangerous.

Its like the Ultra gas station sells what they label 200 octane hi-test gas for 50¢ / gallon, and the other stations are charging $3/gallon for 87 octane...and the web and so forth is loaded with stories of the Ultra stuff blowing people up...and there's STILL a line out around the block of people who want the "cheaper better performing" gas.

Ok!
My 2300mAh from Nitecore arrived and I measured it at 3.68V. I put it in the P25 and guess what? NOW I do see a difference between High and Turbo.

That Ultrafire 3800 was pure junk.

deniscure said:

Ok!
My 2300mAh from Nitecore arrived and I measured it at 3.68V. I put it in the P25 and guess what? NOW I do see a difference between High and Turbo.

That Ultrafire 3800 was pure junk.

Click to expand...

Glad to hear it! Thanks for updating us.

GordoJones88 said:

" NOTE: Due to the high output nature - a high output 18650 battery is required for optimal output. The battery must be able to provide 3.0+ amps of power - which the "cheap" Ultra/TrustFire 18650 batteries are unable to provide. We recommend EagleTac 18650's for best fit, max output, and runtimes. "

Click to expand...

where was this quote taken from?

deniscure said:

Ok!
My 2300mAh from Nitecore arrived and I measured it at 3.68V. I put it in the P25 and guess what? NOW I do see a difference between High and Turbo.

That Ultrafire 3800 was pure junk.

Click to expand...

You will probably find the turbo won't operate if the voltage gets much lower than this. I have an EC25 which is very similar to the P25. A fully charged 18650 should come off the charger at or just below 4.2 volts, I lose turbo on the ec25 at around 3.6 volts. (Which seems to be somewhere between 50-75% of capacity used). This is using an Eagletec 3400, so yours will have different characteristics.

deniscure said:

Ok!
My 2300mAh from Nitecore arrived and I measured it at 3.68V. I put it in the P25 and guess what? NOW I do see a difference between High and Turbo.

That Ultrafire 3800 was pure junk.

Click to expand...

Great thread. I have been considering the P25 and what to feed it. Great info on what not to feed it too!

I see the 3400 Nitecore is avail today on FastTech. Does anyone known who manufactures the Nitecore? I thought I read Panasonic somewhere on the forum.

Thanks for the info on EagleTac too GordoJones88.

Any other great 18650 players? The amount of information available here can be overwhelming.

I am new to the 18650. I'm thinking of the P25 with the Nitecore 3100, which should be more than acceptable.

However, if I can get a great 3400, that will fit, for nearly the same price, then what the heck?!

Do you think these Panasonics will fit/work?
http://www.ebay.com/itm/251231427306?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

I tested my Ultrafire 3400 mAh battery on my Nitecore EC 25 against the Nitecore 3100 mAh ---both charged on the i4 to max.

Time wise: Ultrafire 10 minutes and it went to 50%

Nitecore 3100 mAh was at 31 minutes and going strong when the phone rang and I had to leave off testing my very unprofessional test!