# RCR123 in Surefire L1 Cree...IT WORKS!! And brighter to boot!! + E1L on RCR123



## cryhavok (Sep 8, 2007)

Hey everyone,

Well I received my new Cree Surefire L1 and E1L from OpticsHQ (excellent service!!) and of course was curious to see if I could get some guilt-free lumens by using rechargeables.

One of the newer AW RCR123 cells easily fits inside the Cree E1L body, but some weird things happen with the output. Put short, it is slightly brighter, but every second, it will flicker back to it's normal output level and then return to the brighter state. Weird...

Tonight, I was bored so I tried to fit a RCR123 inside my L1. It didn't quite fit, but it also wasn't impossible to wedge it in. The silver label was bunching up when I tried to slide it in the body, so I took it off and it helped a bit. It is a pretty tight fit, taking a couple of firm shakes to get the battery to slide out, but not so tight that it is nearly impossible to get the battery out. I put on my :tinfoil: and switched her on...whoo hoo no flicking :twothumbs

I will say that the light is VISIBLY brighter than before. Both the low and high levels are brighter to the naked eye. I am very happy with this because while the stock output is phenomenal, I am used to slightly brighter lights that have a bit more throw. My old EDC is a Ti McGizmo S27 PD that I bumped up the drive current from 525mA to 833mA. The light now comfortably reaches out and touches things that it very faintly lit before. I'm loving the beam too because whereas the S27 can reach out a bit further, the area lit downrange is smaller. The L1 puts out a nice large round circle of light that is about 2x the size of the S27 hotspot at 30 ft. 

Here are some measurements on what the light is pulling from the battery. Unfortunately, I can't measure how much the light pulls on low as I understand that the tailcap controls this...

With a fresh Surefire CR123 cell, the light pulls 630mA on high. With a RCR123, the light pulls 830mA on high.

I also took some [email protected] meter readings.
On CR123,
480 on low
3000 on high

On RCR123,
830 on low 
4400 on high

I left the light on high for about a minute in front of the meter and the lux reading didn't change so it has no problem regulating at this voltage. 

Of course, the light gets up to temperature quicker, but I don't think it will be a problem as it seems to have very good heatsinking.


Needless to say, I'm one happy camper :naughty:


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## merlocka (Sep 8, 2007)

I briefly tried an RCR in the L1, and it did seem brighter. I was nervous to try it for very long, and the UF 123 almost got stuck so I haven't tried it since.

I'll probably try it again with some AW's based on your results, thanks.


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## Bullzeyebill (Sep 8, 2007)

You have proven that the L1 Cree uses a boost circuit. The RCR123 is overdriving the circuit/led and you are running in direct drive, no regulation. If the circuit was a buck/boost, or buck, the current from the battery, using the RCR123, would have dropped, not almost doubled. You will have problems down the road.

Bill


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## LA OZ (Sep 9, 2007)

I ran my L1 with LIFePO4 RCR123 and it ran for 25min at Max Lumen. Measured voltage of the battery immediately was 2.2V. For those that may not know, the LIFePO4 battery are 3.2V freshly charged. You will need a special charger for it. I don't mind swapping battery and this is what I used with my L1, Gladius, and A2.


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## Dinan (Sep 19, 2007)

Any update on the status of your L1 w/ RCR's? I've been wondering about sticking one of my AW RCR123's in my L1... but the voices in my head tell me not to!


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## cryhavok (Sep 19, 2007)

I've been using it for about 2 weeks now with only 3.7v RCR123...so far no problems. I believe Bill may be correct in that it is going into some form of DD...but it is strange. I've never head a DD light that pulls current from a battery in such a steady fashion. With my other DD lights, the current measured from the battery will jump around a lot(within a 10mA range); with this light, the current pull stays rock steady. weird.

I've also found that if I can press the switch with just the right amount of pressure, I can get 3 distinct outputs. It looks like low, high w/ cr123, high w/ rcr123. 

The increase in brightness is definitely worth it for me...try at your own risk...but I'm sure you'll get hooked


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## Dinan (Sep 19, 2007)

cryhavok said:


> I've been using it for about 2 weeks now with only 3.7v RCR123...so far no problems. I believe Bill may be correct in that it is going into some form of DD...but it is strange. I've never head a DD light that pulls current from a battery in such a steady fashion. With my other DD lights, the current measured from the battery will jump around a lot(within a 10mA range); with this light, the current pull stays rock steady. weird.
> 
> I've also found that if I can press the switch with just the right amount of pressure, I can get 3 distinct outputs. It looks like low, high w/ cr123, high w/ rcr123.
> 
> The increase in brightness is definitely worth it for me...try at your own risk...but I'm sure you'll get hooked


I really want to try it... but the thought of putting 2xRCR123's in an L4 and blowing it is always in the back of my mind after reading countless threads about it. If the L4 and the L1 are both boost, and putting 2xRCR123's in the L4 will kill it... it makes think that putting a RCR123 in the L1 will damage it as well. But maybe the L1 can handle it? I have tried slipping some AW cells in the body and it fits... it's just a bit tight. Taking the silver label off does help as well, but I haven't mustered up the courage to actually press the switch yet! :mecry:

EDIT: Now that I think about it... people use RCR123's in their Fenix P2D-CE's which is a similar (same?) cree and they seem to work out ok. Would it be safe to assume the L1 would get a similar run-time plot as seen on this thread's graph of the P2D using an AW RCR? (in purple): http://candlepowerforums.com/vb/showthread.php?t=163405


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## Bullzeyebill (Sep 19, 2007)

What are you current readings at the tailcap at start up and after 10 minutes or so. Compare them to the current with one CR123 and post please. Thanks,

Bill


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## cryhavok (Sep 19, 2007)

Here's a quick chart I threw together.







Couple of things to add:
Starting voltage of the AW RCR123 was 4.03V, so it was about 1/2 fully charged. Starting voltage of the SF CR123 was 3.08V

The initial reading of 840mA for the L1 on RCR123 only lasted about 10 seconds...during which it dropped and settled in at 810mA. 

Voltage measured right after the test of the RCR123 was 3.84V. The CR123 was 2.86V

The light got hotter when it was using the RCR123 when compared to the CR123, but not too hot to handle. 

After I completed the tests, I went to my light meter to see if any change in brightness had occurred. The light still puts out the same [email protected] meter numbers as usual with both batteries.

I tried to do the same test with my fully direct drive KL1 running a Seoul P4 off of an AW RCR123. The readings jump and fall continually over a range of about 80mA, so it was impossible to plot anything worthwhile. It does not hold a relatively constant current reading like the L1.


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## Dinan (Sep 19, 2007)

cryhavok said:


> Here's a quick chart I threw together.
> 
> 
> 
> ...


Wow thanks for this! Do you think it would start much higher and drop quicker to that level if the AW cell were fully charged?


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## greenLED (Sep 19, 2007)

cryhavok said:


> One of the newer AW RCR123 cells easily fits inside the Cree E1L body, but some weird things happen with the output. Put short, it is slightly brighter, but every second, it will flicker back to it's normal output level and then return to the brighter state. Weird...



I'm confused. You say the L1 works just fine with R123's, but you point out this "flicker back to its normal output". Either I'm not understanding things right, or something's not right with this setup.


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## jcompton (Sep 19, 2007)

greenLED said:


> I'm confused. You say the L1 works just fine with R123's, but you point out this "flicker back to its normal output". Either I'm not understanding things right, or something's not right with this setup.


 

It works in the L1 but the flickering takes place in the E1L-Cree...


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## greenLED (Sep 19, 2007)

Many thanks, jcompton. Coffee's not hit brain yet.


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## Bullzeyebill (Sep 19, 2007)

Interesting. I wonder if the results would be similiar with a fully charged LiIon? Please do more testing, this is very strange. That flat current draw. Do you have a lightmeter? Would be nice to see a runtime with lightmeter.

We now know that the L1Cree can handle 4.3 volts safely, and that is good.

Bill


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## BBL (Sep 19, 2007)

Bullzeyebill said:


> We now know that the L1Cree can handle 4.3 volts safely, and that is good.



4V are definately above the Vf of the led, meaning it runs in direct drive. That is well out of spec. Considering the L1 is a light that has a planed service life of several years, it is questionable if one can really say it can handle 4V.


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## Bullzeyebill (Sep 19, 2007)

It is out of spec and I usually argue against overdriving a boost circuit. But what we have her is a apparent modest boost in voltage/current to the led at least at a starting voltage of 4.03. It could indicate that the this particular Cree led has a fairly high vf. The real test would be this L1 Cree driven by a fully charged RCR123, at least for a short time to see what the current is. If it jumps well over 1 amp and stays there then forget it. The RCR123 is a different animal compared to a higher capacity LiIon. It's voltage will drop off fairly fast under a load of 1 amp or more. The exception would be an unprotected RCR123 such as a Powerizer 3.6-4.2 volt battery.

Bill


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## MarNav1 (Sep 19, 2007)

I use the green label 3.0 V 17335 cells from Lighthound. They work very well in my L1 lights with no ill effects at all that I can tell. Works just like a primary, haven't done a runtime test. Fits all the L1 bodies, square, round and the new style too. No scraping or removing labels either.


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## Dinan (Sep 20, 2007)

Well I decided to go for it. Stuck my 90%ish AW RCR123 (the only one I had that would fit, took the silver label off, need to slap it to get the cell out but it's not too bad) and tested it out. The low beam is definitely brighter, and the high is higher as well. Left the light on high for about 10 minutes, it seems pretty stable, but it gets warmer faster than the primary. After about 5 mins it reaches a stable temperature which is a tad warmer than leaving the light on high with a primary but it's no where near uncomfortable like an L4 would get. It's still not as warm as my incan E2D gets.

Well so far I like it! I just have to hope it's not killing the LED... but time will tell.


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## jumpstat (Sep 21, 2007)

I would imagine if the output is bluish then the led is seriously overdriven, if it is brighter but with the same tint then it should be ok.....My experience is from direct driving an L1 head (Lux TIR) on a E1L body fed with AW's R123a (Direct Drive). Awesome output, but somewhat bluish tint, no magic smoke though....


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## KDOG3 (Sep 21, 2007)

Very interesting. I have 2 BatteryStation 900mah 3.7v RCRs' sitting here that I don't know what to do with. If they will work in my new L1, that might be an option. Hmmmm....


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## Bullzeyebill (Sep 21, 2007)

Need to look at current at tailcap with a fully charged RCR123 before looking at an RCR123 for long term use. Was not too bad at 4.02 volts, but what about 4.20 volts?

Bill


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## Dinan (Sep 21, 2007)

Bullzeyebill said:


> Need to look at current at tailcap with a fully charged RCR123 before looking at an RCR123 for long term use. Was not too bad at 4.02 volts, but what about 4.20 volts?
> 
> Bill


I'd be happy to do that if I had something that could measure the voltage in the tailcap =(

As for the tint - it looks exactly the same as on primaries.


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## cryhavok (Sep 21, 2007)

Hey Guys,

Sorry about the delay...

Fresh out of my Nano RCR123 charger, my battery measured 4.12V.

Current from the tailcap measured 850mA 

No bluing of my emitter after being on for extended periods...still a pure white color :thumbsup:


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## 270winchester (Sep 21, 2007)

cryhavok said:


> Hey Guys,
> 
> Sorry about the delay...
> 
> ...



speculation:

the Crees are binned at 350mAh.

which means if you have a Cree with VF of 3.4-3.5 volts, it's drawing 350 mAh at that voltage. a 4 volt battery *may* be okay and cause the battery to draw around 850-900 mAh.

:thinking:

makes one think


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## Dobbler (Sep 22, 2007)

What is the P2D-CE drawing on a fresh RCR123A? All my P2D's (4 of them ) run fine on RCR123A in what appears to be direct drive, so what would make the L1 any *less* durable? I would think the L1 were better made and had more heat sinking...


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## Bullzeyebill (Sep 22, 2007)

If the L1 Cree is indeed outputting about 85 lumens with one CR123 then current to the led via the circuit is in the neighborhood of 500mA's. This considering losses due to optic, and heat. That is really good efficiency from one battery. The RCR123 is overdriving the led, but will settle down fairly quickly due to the limited mAh rating of the RCR123. Just my thoughts.

Bill


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## cryhavok (Sep 22, 2007)

On a Cr123, the light pulls 640mA/650mA measured at the tailcap. 


I'm not sure it is purely DD because I have a KL1 head running purely DD and when I take current measurements from the tailcap, the current is all over the place. With the L1, it is pretty darn steady. 

850mA doesn't seem to be overdriving the LED to me...aren't these quoted safe to 1A


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## Bullzeyebill (Sep 22, 2007)

Overdriving in this case is overdriving the circuit, which stops regulating and sends direct current from battery to led. We overdrive when we supply more voltage than the the rated vf of an led.

Bill


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## Dobbler (Sep 23, 2007)

So what is the worst case scenario?


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## Bullzeyebill (Sep 23, 2007)

The worst case depends on the build in heatsinking of the L1 Cree. If 800mA's + to the led is causing the head/body of the light to get really hot then back off. I am talking after 5-10 minutes, light left alone and not in hand. Holding it will probably allow heatsinking to hand but you want to know if it really gets hot. Even if an led can take, say 1500mA's, it does not mean that the L1 Cree can handle that for the good of the led. Need good heatsinking to handle a lot of current. At some point the poor little RCR123 is going to get beat up, though 800mA's won't do that. Still need to see the current at the tailcap at 4.20 volts.

Bill


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## cryhavok (Sep 23, 2007)

The head gets hotter BECAUSE it has good heatsinking...Now whether the head needs more surface area to help dissipate that heat is another question...

However, the body of the light also heats up pretty evenly with the head, so the LED pretty much gets the benefit of the entire flashlight to aid in pulling away and dissipating the heat. Also, no color change in the tint of the LED while on for extended periods also indicates that it is within safe margins in regards to heat buildup and current.

The difference between current readings from my last 4.12V tailcap measurement and a 4.20V battery is going to be marginal...4.12V was "fully charged" according to the Nano charger I use. IIRC 4.20V is the MAXIMUM voltage before the safety circuit in the battery (protected) trips...I don't leave my batteries in the charger overnight so they can be trickle charged until that (dangerously) high voltage.


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## Bullzeyebill (Sep 23, 2007)

Well then you are probably ok, and just as well your namo does not charge above 4.12 volts. Of course the head is supposed to get warm, and maybe really hot if heat sinking is not that great. Look at the KL4 for "hot", and terrible heat sinking.

Bill


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## Dobbler (Sep 24, 2007)

Does anyone make a 1x18650 tube that would work with the new L1 head and tail cap?


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## Dobbler (Sep 25, 2007)

Bummer


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## Ron Schroeder (Sep 25, 2007)

jcompton said:


> It works in the L1 but the flickering takes place in the E1L-Cree...



Isn't the E1L an E1E with a KL1 head? If it is, I am surprized that it flickers. The KL1 should run on from 3V to 9V without a flicker. I run my KL1 (first generation) on a RCR123 all the time.

Maybe the overcurrent protection in your RCR123 is on the edge.


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## Dinan (Sep 25, 2007)

Ron Schroeder said:


> Isn't the E1L an E1E with a KL1 head? If it is, I am surprized that it flickers. The KL1 should run on from 3V to 9V without a flicker. I run my KL1 (first generation) on a RCR123 all the time.
> 
> Maybe the overcurrent protection in your RCR123 is on the edge.


Yea that was the old E1L. The new E1L uses a KX1 head I believe... not much is known about the voltages it accepts I don't think.


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## WildChild (Sep 25, 2007)

Ron Schroeder said:


> Isn't the E1L an E1E with a KL1 head? If it is, I am surprized that it flickers. The KL1 should run on from 3V to 9V without a flicker. I run my KL1 (first generation) on a RCR123 all the time.
> 
> Maybe the overcurrent protection in your RCR123 is on the edge.



The new E1L Cree (KX1 head) won't run on RCR123. As the new E2L Cree (KX2 head) won't run on a single CR123. KX2 on Li-Ion is OK.


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## Ron Schroeder (Sep 25, 2007)

Will the KX2 run on one or two Li-Ions? If it is a buck only circuit, it probably couldn't use the last 1/2 or 3/4 of the capacity of a single Li-Ion before the battery voltage drops below Vf.


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## WildChild (Sep 25, 2007)

Ron Schroeder said:


> Will the KX2 run on one or two Li-Ions? If it is a buck only circuit, it probably couldn't use the last 1/2 or 3/4 of the capacity of a single Li-Ion before the battery voltage drops below Vf.



Someone tested it up to 9V (3 CR123A), so I guess 2 RCR123A would be OK. It also seems the head shutdown just over 3V. A single CR123A won't work in it. For sure, a single Li-Ion won't stay under regulation for all it's life but you still get much useful light and the light will probably shut down before the cell is overdrained.


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## planex (Sep 25, 2007)

I tested my KX2 head in an E1e body with an AW protected 3.7V 750 mAh Li-ion cell. It seemed to have good brightness for about 1.5 hours, then started to get dimmer. After 3.5 hours it was still producing a dim but still useful amount of light. I stopped the test at this point to go to bed. There was some flickering of the beam after about 2 hours or so that would come and go but it wasn't too bad. I am over all very pleased with the KX2's performance on one Li-ion. The long tail ensures that you will not be left in the dark. In comparison, my KL1 head lasted for a little over 30 min and then suddenly strobed and went out with little warning.


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## 270winchester (Sep 26, 2007)

WildChild said:


> Someone tested it up to 9V (3 CR123A), so I guess 2 RCR123A would be OK. It also seems the head shutdown just over 3V. A single CR123A won't work in it. For sure, a single Li-Ion won't stay under regulation for all it's life but you still get much useful light and the light will probably shut down before the cell is overdrained.




interesting.

we need to lobby one of the custom makers here to make a 3-cell E-body that can accomodate 2x protected 18650. Imagine the runtime on that thing...


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## merlocka (Oct 2, 2007)

Tested my L1 (Cree) with both a SF CR123 and an Ultrafire RCR123

With a SF CR123 @ 3.0V, the light draws 690mA.

With an UF RCR123,

@ 0 minutes -- 4.1V -- 920mA
@ 4 minutes -- ???V -- 880mA
@ 8 minutes -- 3.9V -- 870mA


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## Bullzeyebill (Oct 2, 2007)

270winchester, a custom three cell E series body (TB body, for example) would probably hold two 18500's. Not sure if TB made a three cell body for 18500's.

merlocka, your L1 is being "overdriven", but probably ok. No regulation at that current, but it sure will be "bright".

Bill


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## Duc Nguyen (Oct 3, 2007)

Hi everyone ,

I am glad reading this post because I do need help on RCR123 issue, I brought 10 of 16340 880 mAh 3.6 Li-on from dealextreme 2 days ago. It work on my L4,L5 . It did not work on 4 of U2 and 3 of HDS 42 ,60 and T120 , please give me some advice and thanks is advance .

Duc


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## jumpstat (Oct 3, 2007)

Duc Nguyen said:


> Hi everyone ,
> 
> I am glad reading this post because I do need help on RCR123 issue, I brought 10 of 16340 880 mAh 3.6 Li-on from dealextreme 2 days ago. It work on my L4,L5 . It did not work on 4 of U2 and 3 of HDS 42 ,60 and T120 , please give me some advice and thanks is advance .
> 
> Duc


Be careful using 2xRCR123 on the L4 as it employs a boost circuit. Anything above 6V would fry the led. L5 should be okay as the head can be used up to 9v. 

I have not used any DX's rechargeables, although they seem to be more mA and much cheaper than AW's which I am currently using...


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## nuggett (Oct 3, 2007)

Soooo.... back to the L1
Am I to understand its Ok to run it on an RCR? LED is OK as well as the electronics? No magic smoke?


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## cryhavok (Oct 4, 2007)

I've been using mine with a RCR123 for quite a while without a problem :thumbsup:


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## illmatic (Oct 8, 2007)

cryhavok said:


> I've been using mine with a RCR123 for quite a while without a problem :thumbsup:



Which RCR123s are you using? 3V or 3.6V ones?


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## Bullzeyebill (Oct 8, 2007)

It is the high voltage RCR123's that we are talking about here. See post #6.

Bill


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## MarNav1 (Oct 8, 2007)

I have posted this several times but the 3.0v 17335 green labels from Lighthound fit perfectly and work in all the L1 bodies as well. Light doesn't even really get warm.  IMO the 3.7 cells are risky to try in an L1. :mecry:


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## Bullzeyebill (Oct 8, 2007)

I think that the RCR123's 3.6-4.2 volts should be ok at the relatively low current that is being pulled from them. Looks like current starts out at 1 amp or so with fully charged LiIon's then drops fairly fast to 800mA's or so, then it will drop lower till cell voltage causes protection circuit to kick in (protected RCR123's) or L1 circuit starts regulating.

Bill


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## illmatic (Oct 8, 2007)

Bullzeyebill said:


> It is the high voltage RCR123's that we are talking about here. See post #6.
> 
> Bill



Thanks for the clarification. I re-read the thread and realized I missed that...been out of the loop for awhile and didn't know that AW was a dealer/manufacturer and that LiFePo04 was a chemistry.


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## illmatic (Oct 12, 2007)

MARNAV1 said:


> I have posted this several times but the 3.0v 17335 green labels from Lighthound fit perfectly and work in all the L1 bodies as well. Light doesn't even really get warm.  IMO the 3.7 cells are risky to try in an L1. :mecry:



while the lighthound site says they are protected, i don't believe they are. They do not have the strip running top to bottom on them, which is probably why they fit.


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## FlashSpyJ (Oct 16, 2007)

I have heard that I could use a AW RCR123 batt in the new L1. So I did! And I must say that I really hope its ok, because the diffrence in output is really good! I think the L1 should have alot more power than It got with a CR123 batt. And with a AW RCR123 i get that little extra touch!

Im still not sure what we agreed on here, is it ok (safe) to use a AW RCR123 batt or not?


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## illmatic (Oct 16, 2007)

FlashSpyJ said:


> I have heard that I could use a AW RCR123 batt in the new L1. So I did! And I must say that I really hope its ok, because the diffrence in output is really good! I think the L1 should have alot more power than It got with a CR123 batt. And with a AW RCR123 i get that little extra touch!
> 
> Im still not sure what we agreed on here, is it ok (safe) to use a AW RCR123 batt or not?



Did you have to remove the wrapper to get it to fit?


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## FlashSpyJ (Oct 17, 2007)

First time I pushed the AW batt in I didnt remove the label. But I had to really shake it out, it was jammed in there pritty good. I think Its the first part of the tube thats the most narrow. The second time, I rempved the label and then it went in pritty easy, a little hard push and it plopped in there! No trouble to get it out either! Just a firm shake to get it poking out, just to grab with your fingers and pull it out. The first section of the batt tube from the tail end is narrower than the rest of the tube, so when inserting and removing the battery (AW) you have to be very careful though, because you could scratch the plastic cover on the battery.

The output really is much greater with an AW 3.7V batt! I dont really dare to use one before I know its safe or not. I really hope it is safe! It gives the light that little extra push in power that Im missing with the L1. It feels kinda awkard buying a so much more expensive light over the P2D, and get less output. But its ok with the RCR batt...


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## FlashSpyJ (Oct 17, 2007)

I just measured the current draw on the L1 w RCR 3,7V batt and SF CR123 batt. I got around 0,88 amp with the RCR batt, and 0,67 with CR123 batt.

Also measured my E1E body w KL4 and AW RCR123, 1,77 amps, and 2 X CR123 1,40 amps.

Its the voltage we are lookng at? Or is it the current? The LED draw the amount of current it needs right? But if we feed it with a battery with higer voltage it could hurt the battery? The current draw dont increase with a battery with higher voltage? 

I know that the voltage is higher with the AW batt in the L1, but is that enought to hurt the led?
Is the led driven to hard to not let us use a little bit higher voltage than a CR123? I have no expertis in the LED area, as to how much current/voltage they can take safely. But I would like to know!


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## Bullzeyebill (Oct 17, 2007)

The 0.88amps with RCR123 is consistant to what cryhavok got earlier in this thread. Won't hurt battery, and led can take 880mA's ok with good heat sinking. Surefire would not recommend it.

Bill


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## Ron Schroeder (Oct 18, 2007)

Unfortunatly LEDs DON'T just draw the current that they need. If the current that the battery and driver can provide at the particular LEDs Vf is more than the LED can handle, it WILL draw that current and it will be damaged. How much the LED will be damaged will depend on how much over-current, the LED die temperature and how long.

If you have a particularly high Vf LED then the chances of damage or the amount of damaged will be minimal but if you have a low Vf, then the damage (or degradation) will be more.

Sometimes the internal resistance of the cell is high enough to limit the current to a safe level but relying on a weak battery is risky and poor engineering.


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## gunga (Nov 9, 2007)

We need to bump and update this thread since there have been a few questions about the L1 with RCR123 (including frmo me!).

Looks like it's okay, at your own risk of course...

:sigh:


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## FlashSpyJ (Nov 9, 2007)

Things like this is always on your own risk, but we need more conclusive facts about this matter! I want to run my L1 with a RCR, but I wont do it untill there is some more definite facts...


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## 9volt (Nov 25, 2007)

Is there any new info on if the L1 is ok to run on 3.7 RCRs?


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## nuggett (Nov 25, 2007)

ran mine for about 1 or 2 cycles total on rcr123, but I have now settled on LiFePo batts which deliver 3.2 volts or thereabouts. All good so far.


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## Spence (Nov 26, 2007)

Forgive my ignorance, but what exactly are "LiFePo" batteries, and how are they different from LiIon's?
Thanks.


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## NA8 (Nov 26, 2007)

http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery


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## FlashSpyJ (Nov 26, 2007)

happy hunting for the answer, I will no longer be botherd by it since I think I have sold my L1!


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## CalgaryGuy (Dec 4, 2007)

I got my rechageable and here are my findings.

AW LiFePO: 720ma
UltraLast ULCR123R (3.0v Li-Ion): 680ma to 700ma
Surefire: 680ma

All the batteries (with the exception of Surefire) are fully charged and left sitting there for 24 hours.

From those finding, I think that I'll be using my UltraLast batteries for the next little while and will report back in a few weeks.


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## chakrawal (Dec 27, 2007)

What is the runtime of AW RCR123 3.7V?


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## CalgaryGuy (Jan 9, 2008)

Well, it has been a few weeks now running my L1 on UltraLast ULCR123R (Li-Ion 3.0v by Chimistry).

On low, I can get about 1 hour before dropping the battery below 3.0v. On high, I can get 10 minutes before it drop below 3.0v.

On the L1 Cree, even if it below 3.0v, I don't see any difference before or after recharging the battery. The only time that I see a difference is when I use my Arc 4+, the UltraLast ULCR123R just couldn't give enough power to run the Arc 4+ at max level even if it is fresh from the charger.

In conclusion, I don't recommend to run the L1 on UltraLast ULCR123R unless you only have 1 light and only use the UltraLast ULCR123R on that light.


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## RayG (Jan 8, 2009)

Any updates on using the L1 Cree with AW RCR123's?


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## shomie911 (Jan 11, 2009)

RayG said:


> Any updates on using the L1 Cree with AW RCR123's?



I just received a 4-sided L1 with a new CREE head and I tried a AW 3.7V IMR16340 (4.1V actual voltage, had been resting a few days) and it the beams brightness looks near identical to a 3V primary.

I think it would be alright to run it in this configuration, atleast with my particular light, but primaries have been lasting a long time so far and I have plenty primaries. :thumbsup:

Plus the low mode is a lot brighter with a rechargeable making the light less useful. AW's RCR123's don't even fit my 4-sided L1 with the sticker off.


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## shomie911 (Jan 11, 2009)

Here's two beamshots shot with fixed white balance and 1/25 second exposure at F2.7

Confirmed that the brightness on both a rested 4.1V IMR16340 and slightly used 3V primary are identical. See for yourself, the pictures look identical:

4.1V IMR16340





3V Primary


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## DHart (Feb 2, 2009)

Tested a new L1 with an AW protected (black) RCR123 cell for a minute or two today. The cell was definitely a snug fit in the L1 body, but not difficult to get in or out. Measured center of beam axis at 8' distance with a Minolta digital light meter and compared the measured EVs (ISO 100 1/60 sec. @ 8') got:

ON HIGH
L1 with SF CR123 EV 7.0
L1 w/ AW RCR123 EV 7.7

So on HIGH, with the primary at 3v, the lumens are approximately 91% of that with the RCR123 at 4v. The difference was definitely noticible, and a nice bump up in output.

ON LOW
L1 with SF CR123 EV 5.5
L1 w/ AW RCR123 EV 4.9

And on LOW, with the primary at 3v, the lumens are approximately 89% of that with the RCR123 at 4v. The difference was definitely noticible, and a nice bump up in output.

I haven't done any measurements of draw, nor do I know anything about how the use of the AW protected RCR123 would affect the L1 LED.

Anyway, it appears to me visually and to my light meter that a noticible and measureable increase in light output can be achieved by using a 4v rechargeable in the L1.

========
Just as an aside...

Interestingly, I put a TLS Cree Q5 Single Stage LED Conversion Head for E2 on both the L1 and my E1B, each driven by an AW protected RCR123 cell at about 4.1v and the E1B made better use of the battery/head combo than the L1 did, presumably because the electronics in the L1 are a little less efficient than that in the E1B?

L1 / TLS head / AW protected RCR123 / EV at 8' 1/60th sec. = EV 8.1
E1B / TLS head / AW protected RCR123 / EV at 8' 1/60th sec. = EV 8.3

just for for comparison:

Jet III-M stock w/18650 / EV at 8' 1/60th sec. = EV 8.5 (factory stated 225 lumens)

What I learned is that this TLS head is a screamer on an E1B or L1 body with a 4v rechargeable! Nice!!! Very close to the 8.3 EV I get from my Jet III-M (stated 225 lumens) and an 18650 cell (8.5 EV). That some very potent performance out of a little E3-size body!


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## jzmtl (Feb 3, 2009)

shomie911 said:


> I just received a 4-sided L1 with a new CREE head and I tried a AW 3.7V IMR16340 (4.1V actual voltage, had been resting a few days) and it the beams brightness looks near identical to a 3V primary.



If I recall the 4 side body use boost/buck while new 3 side use boost only that'll go direct drive with rcr. 

With above mentioned current draw I would say assuming L1's head has adequate heatsinking, it can safely run on 3.7v rcr cells.


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## DHart (Feb 3, 2009)

Is the driver in the L1 at all susceptible to to damage due to the higher voltage (4.2v) of rechargeables?


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## FLT MEDIC (Feb 4, 2009)

DHart said:


> Tested a new L1 with an AW protected (black) RCR123 cell for a minute or two today. The cell was definitely a snug fit in the L1 body, but not difficult to get in or out. Measured center of beam axis at 8' distance with a Minolta digital light meter and compared the measured EVs (ISO 100 1/60 sec. @ 8') got:
> 
> ON HIGH
> L1 with SF CR123 EV 7.0
> ...



Thanks for the detailed comparison, very interesting!


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## copperfox (Feb 11, 2009)

Got a new 10/65 Cree L1 yesterday. Battery Station yellow RCR123 does not fit. Red label AW IMR16340 cell does fit and is almost exactly the same size as a surefire primary.

The light seems a little bit brighter on the RCR than on the primary, but not much. It gets warm pretty quickly on full output. I haven't done any serious testing. I will continue to use 3.7v rechargeables in it and report back later. 

This thing is Bright! On low with the AW IMR, the L1 is most certainly brighter than my wife's Fenix E01 according to a bouce test. Actually, on low, the L1 almost keeps up to my Romisen RC-G2 Q5 from shiningbeam. Since that G2 is approximately 100 lumens (I think), I'm thinking that the L1 on low is somewhere in the 50lm range. It's hard to tell.

On high using the AW IMR, this thing is a pocket rocket. It's about equivalent in brightness to my Urnabeam Beacon on full output, which is rated at 230lm. Since I know I can't accurately judge the output using just my eyes, I'd estimate that the L1 is between 150 and 200 lumens on high. 

I love this thing.


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## manoloco (Feb 23, 2009)

FlashSpyJ said:


> Things like this is always on your own risk, but we need more conclusive facts about this matter! I want to run my L1 with a RCR, but I wont do it untill there is some more definite facts...


 

+1, like whats going on with the driver, but with precision, how the led does is obvious, but its the driver what makes me really curious.


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## DHart (Feb 23, 2009)

manoloco... The way I look at it... it's just a flashlight.. if something goes out...  Surefire will make it good again, even if there is a charge for the service. OR.... that's just the perfect opportunity to send it off to Milky for one of his custom mods!

copperfox... the black AW protected cells fit in my L1 perfectly, so you might consider those as well.


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## copperfox (Feb 23, 2009)

DHart said:


> copperfox... the black AW protected cells fit in my L1 perfectly, so you might consider those as well.



Yeah, it's not that I thought the IMR would perform better than the black label li-ion, it's just all I had. Sometime I will get around to ordering an AW black label RCR.


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## DHart (Feb 24, 2009)

copperfox... that IMR16340 would be awesome driving a Malkoff P7 with a 3P body... works great with mine... have you tried that combo?


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## copperfox (Feb 24, 2009)

No, I don't own any quad-die LEDs yet :candle:. My budget is telling me to wait. I don't have a 3P either.


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## DHart (Feb 26, 2009)

Just did a ceiling bounce test (at 3' distance) with the L1 CREE using Surefire primary and with RCR123 and at ISO 100 came up with the following EV values, along with some other tests results just for comparison.

Surefire E1B w/SF primary.............4.3 EV
Surefire L1 w/SF primary...............3.9 EV

Surefire L1 w/AW RCR123..............4.6 EV

Jet III-M w/18650.........................4.8 EV
Malkoff M60 w/2*17500.................5.1 EV

The 4.2v RCR123 really kicks the L1 up in potency! 

Haven't tried the RCR123 in the E1B as I'm not sure if the light can handle it.


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## rolling (Feb 27, 2009)

I did something simular today. I put my L1 Cree head on a FiveMega 18500 Body and measured 1.4A. Should that not be a simular value to when you put a RCR123 in a L1?


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## manoloco (Feb 27, 2009)

rolling, thats well above max. spec. 1A should be ceiling 
(well heatsinked), you are risking damage to emitter, since there are no protections in that setup (electronic or thermal).



L1 with AW RCR 3.7V (at 4.2V) as i read from this thread never reaches 1A, its around 900+mA


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## 1996alnl (Feb 27, 2009)

I agree 1.4A is alot for a single Cree emitter.


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## rolling (Feb 27, 2009)

Thats what I thought


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## Onuris (Feb 27, 2009)

I have several L1's and after swapping heads with a couple of my Nitecore Extremes and adding few modded heads, I ended up with a spare stock L1 Cree head that had no home. I also had a spare E2e body and tail-cap, as the original incandescent head is currently being used as host for an LED mod project. My curiosity got the better of me, so against my better judgment, knowing that this combination would way over direct drive the L1 head, I tried it anyway. I half expected it to go  right away, or at best just a bit more brightness, but instead was treated to an *extremely * bright amount of output- way beyond what I expected. I have been using it this way for over a year now without any problems, and I suppose I will not get away with it forever, but as DHart mentioned, SF can fix it, so I have not worried about it to much. I have only used it momentarily like this, for a few seconds at a time, ten sec. or so was probably the most a few times, I cut it off as soon as the head started to get warm. I have thought about using it for longer periods just to see how much it can take, but kind of like having it around right now.

Also, when comparing them to some of my other lights, I notice that the L1's seem to have just a slight green tint to them, some a bit worse than others. This head was the worse by a tiny bit, which is why it became the spare, also it seemed to be just a tiny bit dimmer than the others, but barely noticeable. When on the E2e body though, that green tint all but disappears, it has a much nicer almost pure white colour to it. Which makes me wonder, is it something in the regulation circuit that is causing the slight green hue, or is it just more noticeable at lower outputs?


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## Blindasabat (Feb 27, 2009)

People have noted that many LEDs that show a tint show more of a tint shift at lower drive levels. Driving most LEDs at higher curent tends to lessen the color tint. That is one reason why Henry made the HDS lights PWM instead of current regulated - for tint control at lower levels.
I doubt the driver has any effect beyond the drive level & type. SureFire uses current regulation.


Onuris said:


> ...When on the E2e body though, that green tint all but disappears, it has a much nicer almost pure white colour to it. Which makes me wonder, is it something in the regulation circuit that is causing the slight green hue, or is it just more noticeable at lower outputs?


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## DHart (Feb 27, 2009)

Onuris said:


> My curiosity got the better of me, so against my better judgment, knowing that this combination would way over direct drive the L1 head, I tried it anyway. I half expected it to go  right away, or at best just a bit more brightness, but instead was treated to an *extremely * bright amount of output- way beyond what I expected. I have been using it this way for over a year now without any problems, and I suppose I will not get away with it forever, but as DHart mentioned, SF can fix it, so I have not worried about it to much.



Very interesting!

What cells are you using to drive the L1 head, two primaries? two RCR123's?


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## manoloco (Feb 27, 2009)

Should be primaries or 3.0V rechargeables, i imagine 2 X 3.7 RCRs would  the led pretty fast, but who knows, maybe the answer is a surprise.


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## Onuris (Feb 27, 2009)

DHart said:


> Very interesting!
> 
> What cells are you using to drive the L1 head, two primaries? two RCR123's?



Surefire primaries, which I get for next to nothing at my local gun shop since I buy a lot of stuff from there. Thus I have yet to really feel the need to go to rechargeables, but have been looking at a charger and some 16340 cells- which if I'm correct are similar to RCR123's.


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## DHart (Feb 27, 2009)

Well, if the L1 can handle two 3v primaries, then a single 3.7-4.2v RCR123 shouldn't be a big deal. Cool.


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## NoFair (Feb 27, 2009)

DHart said:


> Very interesting!
> 
> What cells are you using to drive the L1 head, two primaries? two RCR123's?


 
Anything more than a single Li-ion will fry it so probably a 17670 or a 14760. 

Sverre


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## manoloco (Feb 27, 2009)

NoFair said:


> Anything more than a single Li-ion will fry it so probably a 17670 or a 14760.
> 
> Sverre


 
i have tried 2 CR123 (primaries) for a couple of seconds a couple of times on an L1 head with E2E body, it did ok, maybe Onuris is using that setup but more time. otherwise i dont think there would be an "extreme" difference in output Onuris described... cant know for sure until Onuris tells us.


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## Onuris (Feb 27, 2009)

DHart said:


> Well, if the L1 can handle two 3v primaries, then a single 3.7-4.2v RCR123 shouldn't be a big deal. Cool.



Saying that it can handle 6v, actually 6.3v direct driven would be a stretch, as I said- I have only ran it for a few seconds at a time, about 10 sec max.

Would suspect that any real running time would fry it.

What the heck, just left it on for 30 seconds. Put it in a tall mug of ice water, with hopes it would help conduct heat away. Did not fry it yet. Came out a bit warm to the touch at the head.

After cooling down, still works fine.


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## DHart (Feb 27, 2009)

Onuris... your L1 head driven by two cells is an interesting experiment. For myself, I doubt my L1 head will ever land on a 2-cell body. As is, I'm comfortable with driving the L1 with a single RCR123... several on the forum have reported some extensive use of the L1 & RCR123 with good success.


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## Blindasabat (Feb 27, 2009)

I have been running L1 heads direct drive on RCR's [in E1 bodies - see my avatar] for a couple of years. In my testing on Luxeon, SSC, and Cree L1 bezels I have only seen crazy current from fresh 4+ Volt RCR's or the very low Vf warm SSC's.

At 4.1V, one SSC ran at 965mA, the Cree at 1100mA, and the very low Vf [~3.2V] SSC S2 neutral/warm was 1440mA! The neutral SSC is rated to 700mA only.... Oops! It still runs fine, but only on a normal L1 driver, not DD anymore.
On a partially used 3.8V RCR, the same L1 heads test at 300mA, 340mA, and 400mA, so the state of charge also matters a lot.

I also tested the same lights again on a 3.8V 18500 and got the same current as I did on a fresh RCR123, so I try not to run my lower Vf L1's DD on more than an RCR123. The 18500 will supply the high level of current for a long time, while an RCR123 will drop off after a few minutes.

They all run fine [200-440mA] on a 3.0V limited [actually 3.2-3.4V operating] Tenergy RCR123. 

For comparison, on primaries all these ran from only 75-250mA.

Again: Forward Voltage of the individual LED has a huge effect on current they see running direct drive. The current/voltage curve at rated Vf is very steep and that is usually right around the voltage of an RCR123, so as the battery discharges from the initial 4.2V, the current will drop off rapidly.



DHart said:


> Well, if the L1 can handle two 3v primaries, then a single 3.7-4.2v RCR123 shouldn't be a big deal. Cool.


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## DHart (Feb 27, 2009)

Blindasabat.. your experience with this is great. Thank you for sharing that. My budding flashlight electronics knowledge is quite limited at present... and I have a LOT to learn about things like Vf.

Would you expect the current L1 Cree bezel to have Vf's in a fairly predictable (higher?) range? 

If so, would you generally expect any issues whatsoever in running a stock L1 Cree light (a complete L1 light, with driver) with a fresh-off-the-charger 4.2v AW protected RCR123?

Any qualms about DD of a current L1 Cree bezel with a fresh-off-the-charger (initially at 4.2v) AW protected RCR123?


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## Blindasabat (Feb 27, 2009)

DHart said:


> Blindasabat.. your experience with this is great. Thank you for sharing that. My budding flashlight electronics knowledge is quite limited at present... and I have a LOT to learn about things like Vf.


Glad to help. 


DHart said:


> Would you expect the current L1 Cree bezel to have Vf's in a fairly predictable (higher?) range?


You can never say any LED bin [flux or Vf] will be predictable. It is said SureFire buys enough LEDs to get, or pays for, premuim bins, but there is still at least some variation and there will always be one or two out of every one hundred that falls higher or lower. We called it the Luxeon lottery back in the day, and it still exists for SSC and Cree. My L1 Cree seems to have a moderately low Vf since it was the highest current of the bunch besides the neutral SSC, which is said to have a relatively low Vf of around 3.2V. By my estimate, the Vf is around 3.5V. IIRC Milkyspit once told me Cree was very consistant in tint, but varied a lot in Vf, so I don't think you can depend on consistant Vf from a Cree.



DHart said:


> If so, would you generally expect any issues whatsoever in running a stock L1 Cree light (a complete L1 light, with driver) with a fresh-off-the-charger 4.2v AW protected RCR123?


On low - No. It has to run through a 10 ohm resistor to get to the driver first, so it acts like it's lower than 3V. Running on high feeds 3.6-4.2V to a boost circuit that will essentially go direct drive. Some power will be dissipated as heat in the circuit, but most will go to the LED. Not all of it, so we will see what some have said, that the current to the LED is no more than 900mA or so. When I was feeding it direct drive I got 1100mA with no circuit in the way. I've never fit any of my RCR's in my L1's so I'm missing that data, but I would believe the 900mA numbers. That current is OK for the Cree LED.


DHart said:


> Any qualms about DD of a current L1 Cree bezel with a fresh-off-the-charger (initially at 4.2v) AW protected RCR123?


I have always just used DD without a resistor for very short periods [seconds at a time]. Just like the guy who's been running an L1 head on 2xCR123 [6V], you have to be careful of the heat. After the battery has run down some then it will run longer before getting hot.


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## DHart (Feb 28, 2009)

Blindasabat... thank you... appreciate your input!


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## Bullzeyebill (Feb 28, 2009)

Blindasabat said:


> People have noted that many LEDs that show a tint show more of a tint shift at lower drive levels. Driving most LEDs at higher curent tends to lessen the color tint. That is one reason why Henry made the HDS lights PWM instead of current regulated - for tint control at lower levels.
> I doubt the driver has any effect beyond the drive level & type. SureFire uses current regulation.



The HDS is current regulated, constant current regulated using PWM to control the different light levels. Don's current Ti light is using PWM to control two of the three light levels. PWM is used with many constant current regulated lights. 

Bill


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## jp2515 (Jun 8, 2009)

Thank goodness for the search! 

Anyways, like Onuris before me my curiosity got the better of me and I swapped my L1 (Lux) with my L4. I was impressed by the beam, nice and bright (same white beam, just about 5x brighter) I know most people have the L1 Cree but I'm curious to know if running it with 2 cells (2x3v SF primaries) will blow the LED?


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## DHart (Jun 8, 2009)

jp2515 said:


> I know most people have the L1 Cree but I'm curious to know if running it with 2 cells (2x3v SF primaries) will blow the LED?



Well... a 4.2v Li-Ion is definitely pushing the L1 Cree a fair bit... and if I had to speculate, I'd say 6+v may well make for a nice, quick  but you can always give it a try! :shrug:


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## Bullzeyebill (Jun 8, 2009)

Do not use two CR123's. It has worked ok with one RCR123, voltage dropping off pretty quickly and then running in regulation after a bit, but 6+ volts is pushing this boost circuit.

Bill


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## jp2515 (Jun 8, 2009)

DHart said:


> Well... a 4.2v Li-Ion is definitely pushing the L1 Cree a fair bit... and if I had to speculate, I'd say 6+v may well make for a nice, quick  but you can always give it a try! :shrug:





Bullzeyebill said:


> Do not use two CR123's. It has worked ok with one RCR123, voltage dropping off pretty quickly and then running in regulation after a bit, but 6+ volts is pushing this boost circuit.
> 
> Bill



Thanks guys. I purchased a Vital Gear FB1 body (hopefully the L1 head will fit) and I'll probably be getting some AW RCR in the future. Just wanted to double check before I  If I did blow it, I wonder if the head is still able to be modded? :thinking:


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## mudman cj (Jun 8, 2009)

Sure, you can mod the L1 head, but the circuit is not in the head if that is what you are thinking. The circuit for the L1 is in the body. So, if you blow the L1 head by direct driving it on a 2 cell body using 2 primary cells, then you could theoretically open the L1 head and replace the blown LED. 

Allow me to add to the chorus of folks warning you that direct driving a Cree XR-E on two primary cells is a recipe for 

You should be fine running the L1 head on a Vital Gear body with an RCR123 - and yes it will fit.


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## jp2515 (Jun 8, 2009)

mudman cj said:


> Sure, you can mod the L1 head, but the circuit is not in the head if that is what you are thinking. The circuit for the L1 is in the body. So, if you blow the L1 head by direct driving it on a 2 cell body using 2 primary cells, then you could theoretically open the L1 head and replace the blown LED.
> 
> Allow me to add to the chorus of folks warning you that direct driving a Cree XR-E on two primary cells is a recipe for
> 
> You should be fine running the L1 head on a Vital Gear body with an RCR123 - and yes it will fit.



Thank you for the info good sir.


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## cryhavok (Jun 9, 2009)

Mudman is correct, the electronics are in the body of the L1. 

There is room in the head if you want to put a .55" converter. I put a FluPIC in my L1 head and it makes it a fantastic light. Check out this thread for details.

I recently swapped the LED in that head for a XR-E R2 WH and changed the converter to a special Bi-FluPIC . Draws 1.25A on burst from a 17670 and I'm going to guess around 1.5A to the LED. The light previously had a P3/P4 bin XR-E and with the old converter, put out ~5,500 [email protected] Now it puts out 11,000 [email protected] Meter :twothumbs On RCR123, draws ~1A from the battery and does 9,500 [email protected] meter.

For reference, my pervious Milky E2DL Creemator with 1.3A Acorn driver and XR-E R2 WH put ~9000 [email protected] meter.


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## MetalZone (Jun 10, 2009)

Just to chime in that I've been running my L1 cree almost exclusively on AW RCR123's for more than a year. Working just as great as day one. I don't run high for long periods though since low is sufficient most of the time.


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## Forgoten214 (Jun 10, 2009)

No one had any problems running at 4.2V yet?


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## polkiuj (Jun 10, 2009)

MetalZone said:


> Just to chime in that I've been running my L1 cree almost exclusively on AW RCR123's for more than a year. Working just as great as day one. I don't run high for long periods though since low is sufficient most of the time.



Yup! Played with this L1 for a while. I can see no issues. On a side note, this L1 driven with a RCR throws the same as my T10LC2 (with some thermal epoxy on the dome), which I estimate 8-9k lux. Crazy little beast.

This L1 has even met a 17670 but that battery heats up the head much faster and more than a RCR123. Not recommended.


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## MetalZone (Jun 10, 2009)

polkiuj said:


> This L1 has even met a 17670 but that battery heats up the head much faster and more than a RCR123. Not recommended.



Actually that was the 17670 direct driving the L1 on the E2L body since the L1's driver is in the body. the E2L's driver is in the head.

Running the L1 head direct with a 17670 results in it being slightly brighter but yeah, it heats up quite a bit as well.

I guess less voltage sag of the larger battery+no driver on the E2L body will pump out more lumens than the "direct drive mode" with RCR in the L1 body.


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## chnzwh (Mar 11, 2013)

Sorry to dig up such an old thread, but after keeping my L1 Cree on in an AW RCR123A continuously (for around half an hour), the light lost the two-stage brightness function; it only has the low-stage output now. I tried switching batteries (both AW RCR123A & SF123A) and tailcap but it just wouldn't come up on high. Just FYI.


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## Up All Night (Mar 11, 2013)

I've been running mine in this configuration as an EDC for quite some time without issue. I admit, never on high for more than a couple of minutes at a time, as I've never needed to. I'll also admit to having concerns for any extended run on high for this very reason. 
Do you have another E series 1 cell body to try the head on? If you're getting low and swapping the switch didn't help, seems like the electronics could be the culprit. All speculation on my part, hopefully someone more edumacated will chime in.
Also, sorry about your light and thanks for the heads-up!


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## chnzwh (Mar 11, 2013)

Thanks for the advice Up All Night! I just tried the Gen 6 Cree head on a Gen 3 L1 body, the two-stage function was back to normal again & the Gen 3 head won't go to high mode on the Gen 6 body. So now I'm sure the problem came from the electronics in the body. Looks like the circuit of L1 Cree cannot handle RCR123As for an extended period of time (at least mine couldn't).


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