Surefire 2-cell rechargeable for 6P classic?

jcy1012

Newly Enlightened
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Hi, is this is known issue, that the Surefire branded 2-cell rechargeable battery does not fit their 2-cell lights, particularly the 6P Classic? Bought the battery from B&H but it seems to be about 1-2 mm too fat. Does anyone know what my options are for rechargeables? Thanks.
 
The only rechargeable SF cell that I know of BH selling is an 18650 and that won't fit in a stock 6P, which is a 16-17mm inner tube diameter. Some 17650s and most 16650s will fit fine.
 
Ya you need a 16650. Capacity is just under what a 18650 has and they fit just fine. I have them in all my 2 cell SF I don't use for absolute emergency situations.
 
Hi, is this is known issue, that the Surefire branded 2-cell rechargeable battery does not fit their 2-cell lights, particularly the 6P Classic? Bought the battery from B&H but it seems to be about 1-2 mm too fat. Does anyone know what my options are for rechargeables? Thanks.
For the classic 6P, here are my suggestions:
1 - Get a P90 bulb and use 2x 16340 rechargeable batteries.
2 - Get a P60L LED and use 2x 16340 rechargeable batteries.
3 - Get a P61 bulb and use Sanyo 16650 2500mAh rechargeable battery.
They all work well.
 
For the classic 6P, here are my suggestions:
1 - Get a P90 bulb and use 2x 16340 rechargeable batteries.
2 - Get a P60L LED and use 2x 16340 rechargeable batteries.
3 - Get a P61 bulb and use Sanyo 16650 2500mAh rechargeable battery.
They all work well.

2x16340 fully charged @8.4V will flash a P90. Maybe if your cells suck and sag under the amps you'll get a little life out of it. But P90 is designed for 3xCR123A, which actually do sag under load to about 5V, which is what the lamp is designed to handle. P91 is not a 9V lamp either.

I can only assume the same is true of a P60L. Surefire did not design P series to run on anything but primary CR123A

P61 will work fine on one Li-ion, may underdrive it slightly, lowering color temperature a little, and which some claim can shorten its life. But I run Li-ion secondary on other Surefire lamps without issue. Li-ion sag less than primaries under load.

(in before fivemega says similarly... who is the source of this info from other older threads)
 
2x16340 fully charged @8.4V will flash a P90. Maybe if your cells suck and sag under the amps you'll get a little life out of it. But P90 is designed for 3xCR123A, which actually do sag under load to about 5V, which is what the lamp is designed to handle. P91 is not a 9V lamp either.

I can only assume the same is true of a P60L. Surefire did not design P series to run on anything but primary CR123A

P61 will work fine on one Li-ion, may underdrive it slightly, lowering color temperature a little, and which some claim can shorten its life. But I run Li-ion secondary on other Surefire lamps without issue. Li-ion sag less than primaries under load.

(in before fivemega says similarly... who is the source of this info from other older threads)

Yes.
P90 with 2x16340 has a relatively short running time, but higher lumens.
P60L with 2x16340 & P61 with 16650 have a long enough runtime but less lumens.
 
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Yes.
P90 with 2x16340 has a relatively short running time, but higher lumens.
P60L with 2x16340 & P61 with 16650 have a long enough runtime but less lumens.

You missed the warning. Not runtime that matters here, but lifetime. If the lamps do not instaflash and never work again, running these Surefire lamps on anything but primary will massively reduce their lifetime, especially on quality cells.
 
what about LifePo4 123's Chillin'? Too much for a P60?

I use SureFire 123's in my stock 6P(s).

Aren't rechargeable CR123A actually LiFePO4?
3.7V off the charger, rests about 3.4V, and nominally 3.2V.
P60 draws 1.13A, so I think that will work safely, and shouldn't blow the lamp on rested cells. Need to look at the specs of whatever particular cells you're looking at... AW Blue, likely, but those are all gone, right? Have to have some idea of the voltage of two cells under load, and off the top of my head, I have no idea. Rechargeable CR123A bother me because the specs are buried. If sold as LFE16340, then we immediately know what they are. fivemega's input will give security and be definitive.
 
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You missed the warning. Not runtime that matters here, but lifetime. If the lamps do not instaflash and never work again, running these Surefire lamps on anything but primary will massively reduce their lifetime, especially on quality cells.

Thank you for your warning, I have learned it.
But I got other problems that bother me recently.
I have burned several brand new P61s in succession, dead after just a flash.
Using 2x surefire CR123A batteries.
Is the P61 too fragile, or I did something wrong?
 
Thank you for your warning, I have learned it.
But I got other problems that bother me recently.
I have burned several brand new P61s in succession, dead after just a flash.
Using 2x surefire CR123A batteries.
Is the P61 too fragile, or I did something wrong?

I can't explain why this happens sometimes, sometimes consistently, but I suspect they are lamps from a bad batch. I have also flashed a couple MN03 lamps in a row with primary CR123A.

You can contact Surefire. They do not warranty or guarantee their lamps, but they may replace nevertheless. Where did you buy them? Contact the seller also and tell them what happened, and they may replace.

Did you happen to test the voltage of the cells? The more information you have, the better off you will be.
 
The rechargeable CR123 is technically known as the RCR123, which yes, is a Lithium Iron Phosphate cell. Using them with a standard P60/P61 one takes their chances - some can take it, some can't, and some take it but don't last as long as they should. It is hard to find Lithium Iron Phosphate CR123s these days. Most people just use 16350 cells, with all the problems attendant with the higher voltage.
 
I sense that this thread is drifting from the OP's topic more towards specifically incandescent-related options instead of LED-related options.

Which is fine, but all of the above discussion has been covered much more extensively in that subforum.

I'll link up the "rechargeable options" sticky below.

The second issue is that battery terminology is very confusing, and that lamps are much more unforgiving on those specifics.

It makes a great deal of difference if a "rechargeable CR123" is IMR, ICR, IFR, protected, unprotected, 3.0V-diode, 3.6V, 3.7V, 4.2V, 4.35V, etc, etc, etc.
 
Aren't rechargeable CR123A actually LiFePO4?
3.7V off the charger, rests about 3.4V, and nominally 3.2V.
P60 draws 1.13A, so I think that will work safely, and shouldn't blow the lamp on rested cells. Need to look at the specs of whatever particular cells you're looking at... AW Blue, likely, but those are all gone, right? Have to have some idea of the voltage of two cells under load, and off the top of my head, I have no idea. Rechargeable CR123A bother me because the specs are buried. If sold as LFE16340, then we immediately know what they are. fivemega's input will give security and be definitive.

My RCR's are Lithium Ion at 3.7 volts. At one point (I think but not sure) K2 Energy made rechargeable 123's of the Lithium Phosphate that was said to be 3.2 volts fresh off the charger and put out 3.0 under load.
I want to say at one point you could buy those at the SureFire sight, a few years ago. Were they LifePo4 or Li Ion? I dunno but for the life of me I thought they were LifePo4.
I see now K2 calls then Lithium Ion but still says 3.2 volts.

505-A1385-8727-425-D-B851-AD58-FBEA0940.jpg
 
My RCR's are Lithium Ion at 3.7 volts. At one point (I think but not sure) K2 Energy made rechargeable 123's of the Lithium Phosphate that was said to be 3.2 volts fresh off the charger and put out 3.0 under load.
I want to say at one point you could buy those at the SureFire sight, a few years ago. Were they LifePo4 or Li Ion? I dunno but for the life of me I thought they were LifePo4.
I see now K2 calls then Lithium Ion but still says 3.2 volts.

505-A1385-8727-425-D-B851-AD58-FBEA0940.jpg

Note the first line at the bottom, "LFP123A"

Usually, LiFePO4 are named like so: "LFE16340," but I will hazard a guess that because of both the 3.2V spec and their "LFP" nomenclature, these are indeed LiFePO4.

Technically, though usually not referred to as such conventionally, LiFePO4 chemistry is Li-ion.
 
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