Fenix TK75/Thrunite TN30, Can they run on CR123 Lithium Primaries? and what to get?

Can anyone tell me/confirm that both the Fenix TK75 and Thrunite TN30 can run on CR123 Primaries?

Also I just cant seem to decide what one to buy, The TK75 has more throw, I prefer the UI of the TN30, what I really want to know (if anyone is lucky enough to have both) is what one has the brightest spill beam? and what one has the largest spill beam? is there side by side beamshots anywhere?

AusKipper said:

Can anyone tell me/confirm that both the Fenix TK75 and Thrunite TN30 can run on CR123 Primaries?

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Not on both TK75 and TN30.

Thanks, do you know what will happen if I try?

(I ordered the TK75 in the end anyway the extra throw was just too much of a draw for me)

AusKipper said:

Thanks, do you know what will happen if I try?

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All I know is, it is not recommended but please let us know how it turns out if you decided to proceed anyway.

Nope, not according to Fenix. The TK75 will only run in low level light if 123a's are used. I just posted a question as to WHY?????? Burns me up, really wanted one....or two.

What will happen? The light will get the double voltage!
If you think this is a good idea, try it! :thumbsdow
CR123 aren't able to deliver the Power the TK75 will need. They will become hot and

Well I got my TK75, works fine with the 18650's but as advised it doesnt really work with CR123's, it goes on and off but you cant change modes from what looks like the second lowest setting, it also flashes for a bit, I guess to tell you that your using the wrong type of batteries.

AusKipper said:

Well I got my TK75, works fine with the 18650's but as advised it doesnt really work with CR123's, it goes on and off but you cant change modes from what looks like the second lowest setting, it also flashes for a bit, I guess to tell you that your using the wrong type of batteries.

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Awesome, thank you for sharing.

The problem with the 123's is that they can't handle the amount of draw.

18650's can support higher draw devices, 123's can't.

For some really high draw lights, I even go to IMR 18650's, as even the regular 18650's can't support as a high a draw as the IMR 18650's. The IMR versions have much lower mah though...so regular 18650's are the way to go UNLESS they can't handle the draw, and so froth.

TEEJ said:

The problem with the 123's is that they can't handle the amount of draw.

18650's can support higher draw devices, 123's can't.

For some really high draw lights, I even go to IMR 18650's, as even the regular 18650's can't support as a high a draw as the IMR 18650's. The IMR versions have much lower mah though...so regular 18650's are the way to go UNLESS they can't handle the draw, and so froth.

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depends on the circuit, the tm15, t60cs and even the spark sp6 can take cr 123 batteries

TEEJ said:

The problem with the 123's is that they can't handle the amount of draw.

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I'm not sure Teej. It's easily within the 2C discharge capability of the cells. My guess is that it's an over voltage protection mode of some type.

Indeed, the output level is "Mid" as verified by the light meter. 400L

It blinks 3-4 times at start up and then runs unregulated as the voltage decreases, also verified by the light meter.

I could really care less that it doesn't run them properly because to me it's a bonus that it even runs them at all. Typically we complain when certain CR123 lights don't run 18650's.

Patriot said:

I'm not sure Teej. It's easily within the 2C discharge capability of the cells. My guess is that it's an over voltage protection mode of some type.

Indeed, the output level is "Mid" as verified by the light meter. 400L

It blinks 3-4 times at start up and then runs unregulated as the voltage decreases, also verified by the light meter.

I could really care less that it doesn't run them properly because to me it's a bonus that it even runs them at all. Typically we complain when certain CR123 lights don't run 18650's.

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My impression is that the 123's can't handle high draws. Obviously, an individual light's circuitry can do things to compensate for that, taking advantage of the doubled voltage, etc...or by cutting it off to PROTECT it from the doubled voltage.

So a light may run on a fail-soft mode...so at least there's SOME light, etc....but unless its MADE to take the added voltage AND doesn't draw to hard, for too long...123's in a light not meant for them can lead to bad things, or dim things, etc.

IE: The 123 might deliver for a bit, but then run out of the juice needed to MAINTAIN that high a draw.



I have plenty of lights that use 123's and deliver high lumen output, but they are designed to be able to do it. Heck, I can make my XT11 a few hundred lumens brighter if I use two RCR123's instead of one 18650....but it might only run for 30 minutes on high or so before kicking down to medium, etc.

On the one 18650, it can run on high for over two and a half hours.