Is it okay to put three KEEPPOWER RCR123 into SUREFIRE M3LT?
- Thread starter bobb
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leukos
Flashlight Enthusiast
I'm not sure what the upper voltage limit is for the M3LT head, but typically you can use 2x 17500 li-ions to fit the most mAh into an unbored three cell SF body.
ChrisGarrett
Flashlight Enthusiast
12.6v vs. 9.0v would be the difference, assuming that it normally takes 3.2v CR123s.
Chris
Chris
Three KEEPPOWER RCR123 will slightly overdrive compare to 3 primary 123 and will work but M3LT life will be shorter.
I am using pair of KEEPPOWER RCR123 in 6P with P60.
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I'm 95% sure Surefire says that you can use LiFePo4 16340 (nominally 3.2V or so) cells in their LED lights, but I haven't hear any endorsement of higher voltage lithium cells like most LiIon cells. They sell them on their website/amazon and any other LiFePo4 16340 would be fine too.
That's a good point. If it can handle LFP cells, then you will be fine with the 3 V 16340
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Oooh, I was confused for a moment until I realized you were talking about these.
16340 KeepPower 860mAh P1634U1 3V RCR123A Protected Button Top (Micro USB Rechargeable) SEE DESCRIPTION
16340 KeepPower 860mAh P1634U1 3V RCR123A Protected Button Top
illumn.com
Every now and then I forget that regulated RCR123 cells exist
Ya I've never used them but if op doesn't want to use lfp, these are what I would go with. If they fitOooh, I was confused for a moment until I realized you were talking about these.
16340 KeepPower 860mAh P1634U1 3V RCR123A Protected Button Top (Micro USB Rechargeable) SEE DESCRIPTION
16340 KeepPower 860mAh P1634U1 3V RCR123A Protected Button Top
Every now and then I forget that regulated RCR123 cells exist
I'm not sure what there is not to trust. The reason why it's written is 3 V is because they only put out 3 V. Which is a little higher than the 2.6 V or so your CR 123 will put out. Bye I'm sure the light can handle it
The reason I have a hard time believing this is because before that battery came out, even though it was written as 3.0V, the actual voltage was often higher than 3V. It happened a lot before LFP123 was officially released from SUREFIRE, right? Well, since it seems like it will overdrive to some extent, I thought it would be better to use two RCRs as before.
I mean if you can find 2x 17500 or 16500 then that would be the better plan for sure. But the 3.0v keep powers are known to be pretty reliable. I don't have any, but I do have some XTAR lithium ion 1.5v regulated AA and AAA, and they've been solid. It's a pretty standard voltage regulator that's being used, and should be reliable
Sometimes yes it can be used in the same way as CR123
There is no absolute and fixed voltage of primary CR123 because they sag (drop voltage under load). The higher voltage drop under higher load.
Voltage of new CR123A under load of 0.25A is about 3 volt, under load of 1.2A is about 2.5 Volt, under load of 2.4A is about 2.2 volt and do not recommended higher load.
So 3 Volt KEEPPOWER will work with first case nicely, with little overdrive on second case and won't work with third case (too much load).
Also there is a big capacity difference between 16500 and 18500. So by boring flashlight barrel you will get almost double the run time.
You can also use16650 instead of 16500 and get big increase on run time with using extender.
And of course using pair of 18650 will give you tripple extended run time.
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