Quad SSC with 14.8v Batt

[crackerkorean]

I am thinking about doing a quad SSC bike light but was wondering if the 14.8V batt would be enough. Battspace has a 14.8v LiIon for ~$50 bucks so its a relitivly cheap batt.

( 4 * 3.7 ) + 1 (for driver) = 15.8v

Also what amperage would I be pusing the LEDs since I will not be able to push the full 1A

 

[Walt Dizzy]

How about running 2 drivers, each controlling 2 emitters?

I ran into a similar problem trying to come up with a way to run 3 Lux Vs off of a 14.8 v battery. After burning out 2 boost controllers, I gave up and ran 2 emitters off of one buck controller and 1 emitter off of the second.

The down side? Cost, and space. The inside of my light head is very crowded now.

Bonus? I was able to get a 3 power level light using 2 on-off switches. Also, the buck driver is much more rugged than the boost, and does not need heat sinking.

Walt

 

[iggs]

To run 4 led's I would go for a 11.1 Li-Ion battery and something like a maxflex driver.

 

[crackerkorean]

I want to use one power switch, I guess I could do the two controllers.

I dont want to go with a maxflex because of the extra heat created.
Wouldnt the bflex work it would just not run at a full amp, just a little under?

 

[iggs]

The problem with a 14.8v battery and 4 led's is that the forward voltage to the led's is going to be 14 volts for a start + a bit for the driver you just haven't got the slack in the system for the the driver to work so it would 'fall out' of regulation, i.e. the driver would take itself out of the system and it would go into direct drive

14.8v batteries work great with 3 led systems. If you wanted to use a Li Ion battery with 4 led's and a buck driver like the bflex you'd need to use an 18v battery from my calculations

The maxflex only needs heat sinking if your generating over 1watt of power in it. Running 4 led's at 700mA is right on the border line of the heatsinking issue

 

[crackerkorean]

I will stick with the triple for now. That might be an upgrade down the road. It wouldnt add that much more light

 

[znomit]

You could run two parallel strings of two LEDs, I do this with the bflex and it works well...or you could run two strings of 3 (the 3cree MR11 leds/optics from cutter could make a compact 6 led system). You are only at 500mA, less heat issues, more efficiency (I think around 20% more light from 2 leds at 500mA vs 1 at 1A). I think there are 1.4A drivers out there if you want a bit more. Or if you wanted to get silly later you could add a separate driver to run them all at 1A.

 

[Brum]

Go for 5 LEDS and boost or 3 LEDs and buck driver.
With 4 LEDs a buck-boost (very rare, at least as a complete driver) driver is the way to go.

 

[crackerkorean]

For now I will stick with 3 and just use a Bflex. Since this next light will have to be a reliable almost nightly use riding light. I will play around after I get this light done with even more.