Bike Light, 20+ Watts, 7 leds

One year ago I made a nice bike light. 16 Watts total, 2xLuxeonV and 1xLuxeon III at 1000mA.
I was very happy with it.

Then In August we made a comparison test with some friends. One fellow used 100 pcs of 5mm LEDs with total of a mere 9Watts. His light simply outperformed my setup.

Not only outperformed in total output but the efficiency was twice of my config.
It was time to make a significant step and think things over.

I decided that
- I will not overdrive leds. Max. 700mA. Very good efficiency compared to 1000mA.
- Use efficient and bright Lux bins.
- Test heating charasteristic to know my limits

Finally my config is the following
- 5 x Luxeon III, bin TV1J (source: Sandwich Shopper)
- 2 x Luxeon V, bin WX1T (astonishing bright ones! - supplied by PhotonFanatic)
- three nFlex drivers set to 700mA (http://www.taskled.com)
one for 3xLuxeonIII
one for Luxeon V + Luxeon III
one for Luxeon V + Luxeon III
- 10 and 30 degrees optics from L2-Optics. 10 deg for Luxeon V, 30 deg for all Luxeon III's
- powered by an 14.4V/7.2Ah LiIon water bottle battery pack

Here are the results in pictures.
All beamshots were taken with the same manual settings, with daylight white balance.
Build history:
http://pinterweb.freeweb.hu/albums/buildingbikelight2005oct/index.html
Beamshots compared to 100 leds, HID and others:
http://pinterweb.freeweb.hu/albums/beamshots1/index.html
Heat simulation with "qfin":
http://pinterweb.freeweb.hu/albums/heatanalyzis1/index.html

Now I think this will be enough for another year.

:wow:And I thought my Niterider HID setup was excessive

What's the run time on this puppy (at full grunt)?

:wow: Nice light!
That's some mulla LED power you got there.

What's the total weight for the system?

sweet!

It's really interesting that the 100 5mm LEDs setup is just as bright as the Lupine Edison at 16W. I would never have thought of that configuration for a bike light... :laughing: Any pictures of the 100 LED setup?

I like your 7 LED 20W setup, but the colour is a little too "green" for my taste..

I am very impressed - good job on the new light

The only concern that I have is using un-protected, high energy 18650 in series/parallel. This setup can't ensure that cells will not over-discharge, so it is potentially dangerous. Please use extreme caution and/or add protection circuits to the cells to be in the safe side:
link to Li-Ion Protection circuits ...

Will

[Greenish color]
The pictures were taken at daylight digicam setting. In real life it is not so green. True, I got TV1J bins from the greenish side. Lost on luxeon lottery.
Still very usable in outdoor environment.

[LiIon]
The LiIon waterbottle battery I ordered from batteryspace already have protection circuits embedded.

[Lupine HID comparison]
It seems that the HID has lost its initial bringtness. With ballast, it should be in the 60 lumen/watt range. But appearantly it is no more than 25-30 lumen/watt now. I did not know HIDs are loosing most of their brightness in some 100 hours.

Estimated lumens for my setup:
2xWX1T + 5xTV1J
Min:2x147+5x67 Max:2x192+5x87 = 629-819 Lumens (700mA, Tj=25C, w/o optics)
-20% because of heat
-15% because of optic losses (worst case)
Results in 427-557 real lumens (21-27.5 lumens/watt in my case)

[100x5mm led in comparison]
The 100x5mm led setup (indeed a little more than 100) is using 76 pcs of 16cd/15 degree Lucky Light "583" leds. These leds are very good performers. Only 10% less bright than my new Nichia NSPW500CS leds at 20mA. But they have lower Vf, so they are almost as efficient as the Nichias.
Each 6 white leds have one red and one green supplementary leds. The guy who built it hates tints other than white.
Sorry, I have no pictures of it, but it has two parts: 60 leds in horizontally on an alu plate on the bike. The other 40 leds are arranged in 4x10 on a headlight.

[Runtime]
Estimated 5 hours on full 20W. Or 10 hours at 10W. Maybe I will use it on a 24hr bike race. Till than I am happy not to charge after every ride session.

[Total weight]
Without battery it should be under 200 grams, I measured only the heaviest part (heatsink) that is approx. 110g.

Cool monster light!

My TVIJ LuxIIIs look a little greenish too, especially when comparing to some of the blueish binned LEDs (my WX0T Lux V). But cranked up full power in the woods, they still look pretty white!

Do you have plans to encase the light, or clamp it on "as is"? I spend 90% of my time building a bike light enclosure to be somewhat waterproof (in case of rain) and to be able to survive a mild crash or slaps from tree branches. I'd hate to see all your Luxeons splattered around in the woods, picking up optics, etc.

Also, why did you remove the emitters from the stars? Better thermal xfer?
BTW, I liked your thermal analysis and beamshots too.

I will soon have (almost) the equivalent setup (OK, minus 2 LuxIIIs) but, in two separate enclosures. One 3x LuxIII https://www.candlepowerforums.com/threads/99175 and a 2x Lux V that I'm working on now. 2xLuxV on helmet, 3xLuxIII on handlebar.

nightrider,
yes, emitters were removed from star because of better thermal path. I gain 5 C/W thermal resistance. At 4.4W for LuxV's the gain is 22C. Brighter light, longer life. On the other hand I think stars were a little bit large for the 67x67mm area.

Enclosuring the light to make it full waterproof? As usual, this is the last step, and as always, I am missing this final part of build.
Previous light operated fine with 27mm IMS reflectors even filled up with snow.

I tried also Carclo holders and optics, but the optic from L2-optics fits very-very tight. Removing it is a real pain.

Hi Pinter - nice setup. If you would like to enhance your efficiency even more at some point, consider running an RGB setup using Lux IIIs and Vs.

That is a lot of lighting power. Very impressive.

That looks like a car head light beam.

I need one.

Brian