IMR, Who uses them, How and why?

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DasFriek
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IMR, Who uses them, How and why?

 IMR's. I was suggested to look into them for some added flashlight fun and given a good link on where to buy them. But im kind of at a loss as to where id use them? So i thought id ask whats there best applications?

Ive done my research so i know the chemistry and internal resistance and safety of the cell, But i don't know exactly what kind of lights would benefit from them.

One bit of my confusion is this, I know the driver controls the voltage and amperage an emitter see's. But every Li-Ion cell i own will push more amps than any driver can use already. So how does the IMR push more amps threw it?

Also, Im not to worried about the driver as i think an IMR wont affect them. But too much amperage on an emitter can be pretty bad. Granted i have tested all my lights for tailcap amp readings and none come close to pushing the emitter close to its max.

My 1 amp emitters see .7amps

1.5 amp emitters see 1.2amps

And so on. Also what happens in regulated lights, Im thinking nothing extra? 

In a 2x18650 regulated light does an IMR have any impact there? 

Lastly, Has an IMR burnt anything of yours up? And are they suspect in early deaths of drivers and emitters in any way in long term use? 

bushytails
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An IMR cell won't make an emitter draw more current than it otherwise would at the same voltage, or a driver put out more current than it normally regulates at.  Rather, IMR cells let you use driver and emitter combinations that draw more current than you could safely supply from a regular cell.  An IMR cell won't improve your existing lights, but will let you power lights you wouldn't be able to run off your current cells.

--Bushytails

DasFriek
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But, Is that just cells that are unregulated?

Also, Ive not seen a light my regular 2400mAH cells cant run. What type of setup would need/use/require an IMR cell? Of the lights below, Which would benefit from an IMR cell?

Sky Ray G6 Cree R5 5-Mode 18650

KD C8 CREE XML T6 1000 Lumen 5-Mode 18650

SIPIK SK68 Cree Q3-WC 120-Lumen Convex Lens 14500

Olight M20s Warrior 2x CR123 or 18650

SolarForce L2r 2x AA 

gcbryan
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None and what do you mean by "unregulated cells"? There are unregulated flashlights and unprotected li-ion cells which only has to do with protecting again overcharging the cells or running the cells too low.

DasFriek
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Ooops, Im sure i meant "unregulated lights". I know there is no such thing as a regulated or unregulated cell.

I need to start proof reading my posts 3x now, I always try and reread them as spell check lets alot of mistake threw still.

So the lights i listed above wouldnt benifit from IMR's?

Can you name a light that would? 

DasFriek
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Ok, I can definitely see how that could use all the power you can find.

So just to get this straight, It basically takes a very uncommonly led you normally wouldn't see used in a light you buy from MF or DX. And is mainly for serious high output custom built projects.

Or a reworked 3x XM-L build where each emitter gets 3+ amps.

Well that saves me some money for now, Im still not to the point im ready to drastically mod internals yet. 

2100
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Practical examples that I can think of now...

Xeno E03.  2.4A on IMR 14500.

Lumapower Incendio V3U XM-L on 16340.

Solarforce L2m on 18350/16340 with XM-L/SST-50 drop in.  Or one of those quad XP-G drop-ins which goes up to 5.6A.

Firefox 40W, but I guess with excellent 3 x 18650s it is still doable.  Shorty custom HIDs up to 65W with the cylinder ballasts, each cell supplies 6A plus.

Even your incoming Sky Ray 3xT6 can benefit from IMR, 2 x 18500 coz you may encounter up to 4A (say for example that's probably worst case with a lower driver voltage protection cut), a Li-Co 18500 probably would not do.

With customs its always pushing the envelope for the guys, so IMRs are always popular.  The usual which you see around here are like max 6 x XM-L?  Others squeeze in SST-90s.  Hardcore mods like Osram 64663 400W.  When you hit 1kW LiPo packs are always more convenient.   Sealed

higbvuyb
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bushytails wrote:

An IMR cell won't make an emitter draw more current than it otherwise would at the same voltage, or a driver put out more current than it normally regulates at.  Rather, IMR cells let you use driver and emitter combinations that draw more current than you could safely supply from a regular cell.  An IMR cell won't improve your existing lights, but will let you power lights you wouldn't be able to run off your current cells.

--Bushytails

IMR cells tend to have lower internal resistance and have less voltage sag with higher demand.

DasFriek
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Well, I guess it wouldn't hurt to get a few and see if any of my lights respond to them. I have more than enough lights that can run for hours at a time on high so it wont hurt me to have one that is only 30 minute runtime but being alot brighter.

I have a few single 18650 XM-L lights L2 and K8 styles coming that will be my mod lights as i want to start fooling around with drivers and modding and swapping and building my own drop-ins with custom emitters. Some may benifit and some may not, But ill never know until i try. And the link i was given has them for $5 for an 18650 1500mAH.

2100
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Yep, looking forward to my bestinone.net IMRs too Dasfriek.  Thanks to mitro's tests that I took the leap.

DasFriek
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Yup, Thats where im headed now to make my purchase. I wanted some 14500 but i dont have many lights that use them, But if i buy the cells ill buy the lights to use them. lol

BTW mitro has alot of good and current cell info up there that people should look at more if they are in the market to buy cells.