18650 Li-Ion Batteries

[NewStuff]

The big thing I have though about their torches and bike lamps etc is the habit of parallel wiring the LEDs. They use generic components, nothing seems to be specialised. Typical of their high powered torches is say 6 LEDs all parallel wired and sharing 9 amps from a generic driver, so they getting approx 1.5 amps each, with some getting more than others as internal resistances will vary slightly. The finished product will appear on eBay claiming something silly like 10,000 lumens.

Oh, far more. 1 real world Lumen is at least 3 Chinese Lumens. I saw a seller claiming "a genuine 4000 Lumens" for a single emitter XM-L T6.

 

[royfellows]

So, Roy, what would be a realistic output from such a set-up?

Hard to say as you don't really know what you getting, but working of Cree data sheet, assuming that they are XM-L 2 U BIN which is unlikely, I would say just over 4000 lumens falling to about 3500 as the torch gets hot, which it will.

In reality, you cant take as said even the emitters they claim. As I posted before somewhere, I bought a 6 LED torch off eBay for ?20 which claimed XML emitters and 10,000 lumens. I stuck top quality Sanyo cells in it for a start and then tested it underground. It was very impressive until I put my X3000 on beam full power and the caplamp beat it very obviously. Actually, it toasted it

And that was 2 only genuine Cree XML 2 U2s at the full 3 amps.

So there is the story.
I tend to take the torch underground a lot for photography, it is very good value for money however described, so don't let this put you off one.