Lightest and brightest 18650 Headlamp?

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
This has probably been hashed out before, but I'm interested if there any updates for 2022. I'm looking for the lightest and brightest 18650 headlamp for running. Runtime in the range 1-1.5 hrs, so hoping for something really bright (>600 lm continuous). Not floody, since I've found that blinds people running with me.

It seems like the champ would be a Zebralight, although it hasn't been updated since 2018:
H600c Mk IV 18650 XHP50.2 4000K High CRI Headlamp
126g total with NCR18650GA battery and headband

I currently have a Fenix HM65R-T Trail Running LED Headlamp
Weight: ~141g with battery (138g with unprotected battery)

I find the step down in the HM65R-T annoying. It's just not that bright once it steps down to 400 lm. The Fenix SuperRaptor 2 might be the answer, but I haven't seen reviews showing what the stepdown looks like.

I imagine if the headlamp had true thermal regulation with PID, it should be able to maintain a pretty high output, since I'd get cooling wind from running and I'm often running when it is cold out. Though, the cold weather (32F this morning) really hurts runtime from increasing internal resistance in the battery. My Zebralight H52 only held 300 lm for 30 min this morning, when it can do just over an hour at room temperature using a Vapcell INR14500 L10 1050mAh. But, with enough heat from the LED, you'd think it would keep the battery warm enough.... Anyway, thoughts?
 

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
P.S. My H52 seems like the king of lightweight and high output small headlamps. 70g including the battery and headband! Holds 300 lm for up to an hour. Too bad Zebralight dropped 14500 compatibility on their AA headlamps. I won't be able to replace it if it breaks.
 

sirpetr

Newly Enlightened
Joined
Sep 7, 2012
Messages
96
Location
Czech Republic, Prague
You posted just headlamps without cables but I am personally not fan of these lamps for running. Its night and day to run with counterweight (battery) on the back of your head. We have lightweight S2X lamp which was developed for that. I have got lot of running and racing experience - orienteering, rogains, 24h races etc. and find that L shaped and similar cord-less lamps are great, versatile and durable, but not best for running.

When having latest LEDs, like XP-L2, W2 or V6 bins and aluminium body, its quite easy to cool down even 600 lumens. If I remember right, S2X does not overheat when left on the table on 470/600 lumen mode.

Yes, cold weather poses problem for every battery regardless chemistry, internal resistance gets higher but shouldnt hurt runtime so much like you described - there are not many Amps flowing from battery if we are still talking about 600 lumens. I havent seen either any real/measurable problem with higher lumens but we exclusively use just good quality 18650 cells, which have in general lower internal resistance than any 14500. What temperatures are we talking about?
 

Lynx_Arc

Flashaholic
Joined
Oct 1, 2004
Messages
11,212
Location
Tulsa,OK
I think 600 lumens for an hour is about the limit of most 18650 headlamps and that may also be at a declining output on some of them I would consider 400 lumens myself with a decent amount of throw that many headlamps have that is doable in the 2+ hour range. I've tried jogging with an 18650 headlamp and as I remove the top strap it bounces way too much for my usage. A light with an external 2 or more cell pack would be a lot more ideal as higher output would be easier and the weight on the front would be dropped significantly.
 

sirpetr

Newly Enlightened
Joined
Sep 7, 2012
Messages
96
Location
Czech Republic, Prague
@Lynx_Arc : Your numbers are way off!
One protected 18650 stores at least 12Wh of energy. Two XP-L2, V6 LEDs, at 50°C together give 660 lumens, so each LED 0.645A, 2.75V which is 1.77W, effciency of each bare LED is 186lm/W. Then you have to take into account also efficiency of energy conversion, so 90% efficiency needs 1.96W. Two LEDs need 3.92W and provide 3h runtime with constant 600 lumen output (90% optical efficiency). Also note - all numbers here are very pesimistic, efficiencies (LEDs, driver or optical) can be even slightly better. Everything can be easily verified from pct.cree.com. Its real!
 

Lynx_Arc

Flashaholic
Joined
Oct 1, 2004
Messages
11,212
Location
Tulsa,OK
@Lynx_Arc : Your numbers are way off!
One protected 18650 stores at least 12Wh of energy. Two XP-L2, V6 LEDs, at 50°C together give 660 lumens, so each LED 0.645A, 2.75V which is 1.77W, effciency of each bare LED is 186lm/W. Then you have to take into account also efficiency of energy conversion, so 90% efficiency needs 1.96W. Two LEDs need 3.92W and provide 3h runtime with constant 600 lumen output (90% optical efficiency). Also note - all numbers here are very pesimistic, efficiencies (LEDs, driver or optical) can be even slightly better. Everything can be easily verified from pct.cree.com. Its real!
You are correct....I got 2 threads mixed up in my brain...... another thread has someone that has a 2AA light that claims 800 lumens and is only getting 600 while 18650s can do close to 2 hours at 900-1000 lumens or a little more
 
Last edited:

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
You posted just headlamps without cables but I am personally not fan of these lamps for running. Its night and day to run with counterweight (battery) on the back of your head. We have lightweight S2X lamp which was developed for that. I have got lot of running and racing experience - orienteering, rogains, 24h races etc. and find that L shaped and similar cord-less lamps are great, versatile and durable, but not best for running.

When having latest LEDs, like XP-L2, W2 or V6 bins and aluminium body, its quite easy to cool down even 600 lumens. If I remember right, S2X does not overheat when left on the table on 470/600 lumen mode.

Yes, cold weather poses problem for every battery regardless chemistry, internal resistance gets higher but shouldnt hurt runtime so much like you described - there are not many Amps flowing from battery if we are still talking about 600 lumens. I havent seen either any real/measurable problem with higher lumens but we exclusively use just good quality 18650 cells, which have in general lower internal resistance than any 14500. What temperatures are we talking about?
That's a good point. I'll look at some cabled lights. I have no problem running with the H52 because it is so light. Even a basic headband stays put.

I only run for about 1-1.5 hrs before dawn or after sunset, so an 18650 might be overkill. I don't need 8hr+ runtimes. But, there's nothing quite between 14500 and 18650 that has a good trade-off between weight and capacity.
 

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
You are correct....I got 2 threads mixed up in my brain...... another thread has someone that has a 2AA light that claims 800 lumens and is only getting 600 while 18650s can do close to 2 hours at 900-1000 lumens or a little more
I'd be interested in ~1000 lumens for 2 hours!

It sounds like the Zebralights might be able to do that with sufficient cooling, but not guaranteed.
 

desert.snake

Flashlight Enthusiast
Joined
May 8, 2017
Messages
2,064
Location
Eastern Europe
I'd be interested in ~1000 lumens for 2 hours!

It sounds like the Zebralights might be able to do that with sufficient cooling, but not guaranteed.
Yeah, there's too little metal in them to dissipate that much heat for so long, otherwise they're great. Lucifer seems to have the most powerful lamp on his head in general (Lupine Alpha 8100 lm does not count as it goes on a helmet)
1644783196233.png
 

Lynx_Arc

Flashaholic
Joined
Oct 1, 2004
Messages
11,212
Location
Tulsa,OK
I'd be interested in ~1000 lumens for 2 hours!

It sounds like the Zebralights might be able to do that with sufficient cooling, but not guaranteed.
I looked over there at the SC600W that is rated at 875 lumens for 2.9 hours which isn't too much away from 1000. I'm not sure that is continuous output though I don't have much knowledge of Zebra products they are out of my league financially speaking.
 

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
I looked over there at the SC600W that is rated at 875 lumens for 2.9 hours which isn't too much away from 1000. I'm not sure that is continuous output though I don't have much knowledge of Zebra products they are out of my league financially speaking.
I was looking at this one:

This is what they say for runtime:
  • High: H1 1616 Lm (PID, 2.5 hrs) or H2 1010 Lm (PID, 2.9 hrs)/579 Lm (PID, 3.1 hrs)/305 Lm (5.3 hrs)
Since they are all close to 3 hours, that leads me to believe it drops to about 600 lm no matter which setting you have it in. Still, 600 lm for three hours is a lot.
 

Lynx_Arc

Flashaholic
Joined
Oct 1, 2004
Messages
11,212
Location
Tulsa,OK
I was looking at this one:

This is what they say for runtime:
  • High: H1 1616 Lm (PID, 2.5 hrs) or H2 1010 Lm (PID, 2.9 hrs)/579 Lm (PID, 3.1 hrs)/305 Lm (5.3 hrs)
Since they are all close to 3 hours, that leads me to believe it drops to about 600 lm no matter which setting you have it in. Still, 600 lm for three hours is a lot.

Looks more like 500 lumens to me perhaps a little less even still even 400 lumens is a bunch of light for about 90% of the tasks most do.
 

desert.snake

Flashlight Enthusiast
Joined
May 8, 2017
Messages
2,064
Location
Eastern Europe
I was looking at this one:

This is what they say for runtime:
  • High: H1 1616 Lm (PID, 2.5 hrs) or H2 1010 Lm (PID, 2.9 hrs)/579 Lm (PID, 3.1 hrs)/305 Lm (5.3 hrs)
Since they are all close to 3 hours, that leads me to believe it drops to about 600 lm no matter which setting you have it in. Still, 600 lm for three hours is a lot.

I have exactly the same. An excellent flashlight, on some specimens there may be a blue spot in the center of the beam, but it is completely invisible in nature.

Here tested the same flashlight, but with frosted glass. This is a graph with good water cooling, 2 hours 20 minutes in total on Samsung 35E 3500mAh, it can be compared to running in winter, like now.
1644784828352.png
 

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
I have exactly the same. An excellent flashlight, on some specimens there may be a blue spot in the center of the beam, but it is completely invisible in nature.

Here tested the same flashlight, but with frosted glass. This is a graph with good water cooling, 2 hours 20 minutes in total on Samsung 35E 3500mAh, it can be compared to running in winter, like now.
View attachment 23990
Do you have an estimate of how many lumens that plateau is?
 
Joined
Mar 4, 2012
Messages
642
Do you really need hundreds of lumens? Zebralight in single package is going to be lightest and most efficient. I'd use an AA version if you can live with less light.
 

n2mb_racing

Newly Enlightened
Joined
Oct 31, 2020
Messages
47
Do you really need hundreds of lumens? Zebralight in single package is going to be lightest and most efficient. I'd use an AA version if you can live with less light.
Sure, I don't need more lumens... But, I wouldn't be on this forum for needs. :) I want more because it's a fun toy.

300 lumens from my Zebralight H52 is great, 184 lumens in H2 mode is usable for running. 600 lumens of high CRI 4000k light would be even better. :)

It's unfortunate that the new Zebralights don't work with 14500 batteries. I've tested runtime with my H52 using eneloops and the runtime is a lot lower compared to a 14500, and the 14500 is 10 grams lighter.
 
Top