Need 800 lumens for 8hr

Asusvivobook

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Help me out fellas, I need more runtime.
I need ~800-1000 lumens for 6-8hr work day. Floody+ spot would be nice.

I don't think a single 21700 will be enough.
And a 2x 18650 headlamp doesn't seem to exist, do they?

I'm thinking of getting a Fenix hp25r and replacing the battery pack with a 2x 18650 holder.

Can somebody suggest a better option?
Can someone suggest a better rear-battery headlamp for this procedure?

Thank you 🤞
 
Fenix HP30R-V2. Remember, any light over 5-600 lumens is likely to step down. You might not get that kind of runtime and brightness possible for that duration from any headlight. Too much heat, too little power. Try a 1500 lumen 18 volt Milwaukee floodlight and aim it at your work. They have one model with a clamp and pivots, and one with different angled flat surfaces for aiming up and down with a hole for hanging it on a piece of e.m.t. pipe. Milwaukee makes 18 volt batteries up to 12 amps. That should give you plenty of runtime. With how much you're going to spend on a headlight that can't do what you want it to, a tool battery light with a decent sized heatsink that will stay at the required brightness level might be a better option. You're looking at a headlight that uses 2 21700 batteries max. The Milwaukee 18 volt 12 amp battery uses 15 4 amp 21700s.
 
Thanks for the suggestions. That hp30r is huge! It might be built for a hard hat. I need smaller, and mobile.

I'm willing to build a battery pack to give any headlamp more runtime, but I need to know what light to work on.

Is That Fenix hp25r my best external-battery-headlamp option?
 
Help me out fellas, I need more runtime.
I need ~800-1000 lumens for 6-8hr work day. Floody+ spot would be nice.

I don't think a single 21700 will be enough.
And a 2x 18650 headlamp doesn't seem to exist, do they?

I'm thinking of getting a Fenix hp25r and replacing the battery pack with a 2x 18650 holder.

Can somebody suggest a better option?
Can someone suggest a better rear-battery headlamp for this procedure?

Thank you 🤞

Best of luck to you in your search

However, I do not believe what you seek exists at this time
 
You find something like that let me know. If you don't mind changing batteries every 3 hours you could use a malkoff M91 with a 3X18650 body. She will run for 3 hours at 800 Lumens.

My bad did not see you were after a headlight.
 
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You did not mention a budget, since you did not and money may not be an issue, then you can easily get what you want from Lupine headlamps, but be prepared to pay some coin.

The Betty is their largest headlamp and still relatively compact but can put out over 1000 lumens for 10hrs with their largest battery, and the Wilma is a bit smaller and puts out 1000 lumens for 14 hrs with the largest battery, and the Piko can also achieve 8 hrs at 650 lumens, and is more compact than the Betty or Wilma. check them out.

Here is the Betty: https://www.lupinenorthamerica.com/product/betty-rx-14-headlamp-system/
Here is the Wilma: https://www.lupinenorthamerica.com/product/wilma-r-x14-headlamp-system/
Here is the Piko: https://www.lupinenorthamerica.com/product/piko-rx-7-headlamp-system/

Good luck.
 
+

Two 21700 headlamp;
in Spotlight mode says 800lm for 12hr, figure 10hr to be safe

That looks like a formidable HL, but after using my much lower wattage / output Fenix (1x16340) in the garage recently where ambient is already creeping up, I have to wonder how warm that bad dog would be on my forehead with all that wattage being dissipated. On a hard hat at work it would probably be OK, but I don't wear a hardhat in my garage (or apt.). I've been wanting something w/ more output, but not wanting more heat. Always tradeoffs.
 
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Some sanity check math:

Directional LED sources (LEDs, optical system, driver) are around 100 lm/W (some are a bit higher, some are lower, but this makes the math easy), so for 800 lumens out the front, you're talking roughly an 8W source. We'll ignore the heat implications of that 8W source for now, and focus on the batteries. For 6 hours of operation, that's 48 watt-hours.

A 3500mAh 18650 is about 12 watt-hours, and a 5000mAh 21700 is about 18 watt-hours. Those 48 watt-hours need 4x 18650, or 3x 21700 cells. So about 2 hours of 800 lumen operation per 21700 or an hour and a half per 18650. Moving up to larger sizes, a pair of 26800 or 32650 cells would come close to having enough energy - you're looking for around 14 amp-hours.

Looks like the Lupine units have sufficient battery to deliver the output and runtime they claim, but the Fenix HP30R steps down somewhat from the rated output in order to achieve the claimed runtime.
 
If you're willing to change out the batteries, the Fenix HM75R might do the trick for you.
https://fenix-store.com/collections.../fenix-hm75r-rechargeable-industrial-headlamp

Then for replacement batteries, you could look into the new Nitecore batteries. The new 18650 from them has a 4000mah capacity and the 21700 has a capacity of 6000mah. https://www.nitecorestore.com/NL1840HP-4000mAh-Rechargeable-Battery-p/bat-nite-18650-nl1840hp.htm
https://www.nitecorestore.com/NL2160HP-Battery-p/bat-nite-21700-nl2160hp.htm

You could also check out Lucifer lights. https://luciferlights.net/en/headlamp-longest-battery-runtime

Another option to consider is Nite Rider. Even though it's a Mountain bike light, it can still be used as a headlamp. https://www.niterider.com/collectio...ems/products/pro-2200-enduro-front-bike-light
You'll just need to purchase the headband. https://www.niterider.com/products/explorer-headband

Good luck with your decision 👍
 
Satisfied Lucifer customer here. The M6 (2-18650) will give 10 hours at 450 lumens or 4 hours at 960 lumens. Battery swaps are extra easy if you have an additional battery case (unplug-plug), or relatively easy with loose cells.

As an aside, what are you doing that wants 800 lumens? That's a lot of light.
 
Well I'm sorry that I don't mind paying European wages or American even for my lights to be produced.
 
Lucifer lights looks interesting if you can get passed the name :) Where are the US distributors, or do you have to order direct from Czech Republic?
 
Well I'm sorry that I don't mind paying European wages or American even for my lights to be produced.
I don't mind either. I've got over 2 dozen SureFire models in my collection. Also have some excellent models Made in China. That doesn't automatically mean slave labor chained to a work-table and forced to urinate and defecate into a garbage bag.
 
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