Life with the Jetbeam Jet-I MkII and a 14500.

Lunal_Tic

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It would seem from posts that a number of folk run their Jet-I MkII on a 14500 Li-ion cell. It's been a number of months since this combo has been available and I was wondering if you've noticed any lumen degradation with the Li-ion or output drop off if you switch back to a standard, 1.2V-1.7V, cell?

I've only just started running my light this way because I was loathe to get yet another battery type in my arsenal. It is considerably brighter but heats up so quickly that I'm concerned about cooking it if I leave it on for prolonged use.

So what have you found while using this combo. Is it a keeper or are you more inclined to run primaries in it more often than not?

TIA,
-LT
 

moon lander

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i think your not supposed to use it on high with the lithium 14500 for more than 10-20 minutes at a time. heres the link to that info (towards the bottom)
 

HiltiHome

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You certainly will not use it longer than 10min. on high, cause it's getting terrible hot....
 

jsr

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I only have an MKI and it gets HOT on a 14500 quick! The MKI draws more current than an MKII though, resulting in brighter output, but more heat also. I've run my MKI for 20-25 minutes straight...yes, it got hot, but no problems. Eventually though, I was running my MKI on a 14500 for about 30 minutes, but it was cool because of a very cool/cold breeze (I was on a bike) and the LED turned dim...aboug 15 lumens. Not sure if the LED went or the driver. I got a replacement head which has been going well, but I also haven't run it for 30 minutes anymore, but I still have run it for 15-20 minutes and it hasn't seem to have degraded in output. It does look dimmer, but that's because I've gotten used to much brighter lights. Relative to lights I had compared my Jet1 MKI to when I first got it, it looks the same, so there hasn't been any output drop that I've been able to perceive.
 

Lunal_Tic

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Thanks for the input guys. For some reason I thought there were more folk feeding their MkIIs a steady diet of Li-ion. At least it does seem to move the heat out from the LED quickly. Mine gets warm within a couple of minutes or less on Medium output. I still haven't run it more than 5 continuous since I first tried the new cells out.

jsr, is your replacement head a MkI or MkII? Seems I remember reading the MkIIs were dimmer in general.

-LT
 
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