Direct drive MC-E from LiIon 18650?

[Fallingwater]

Quick question: how much current does a MC-E (or SSC P7) draw if connected to a fully charged (4.2V) 18650 LiIon? Enough to burn itself to hell even when well heatsunk, or manageable?
Thanks.

 

[steve6690]

Depends on the voltage bin of the emitter. I'd imagine an MC-E would fry, even allowing for a bit of sag depending on the battery you select. I have a K bin MCE hooked up to my bench supply at the moment. Vf at 2.8 amps is 3.3V. You'd need to try and get a suitable voltage bin which I'm not sure you can do with the MC-E, but you can with a P7. I'll wind the input up to 4A tonight and measure the Vf

 

[bbgobie]

I've done it for 1-2 seconds at a time on my bench at home.
Never tried any longer, and never long enough to really take measurements.

 

[350xfire]

Quick question: how much current does a MC-E (or SSC P7) draw if connected to a fully charged (4.2V) 18650 LiIon? Enough to burn itself to hell even when well heatsunk, or manageable?
Thanks.

I've driven my two P7 modded Mag Lites directly with 3 D alkalines at 4.5v with no issues. With my variable power supply, the LEDs run 3 amps at around 3.7V driven directly.

 

[steve6690]

Depends on the voltage bin of the emitter. I'd imagine an MC-E would fry, even allowing for a bit of sag depending on the battery you select. I have a K bin MCE hooked up to my bench supply at the moment. Vf at 2.8 amps is 3.3V. You'd need to try and get a suitable voltage bin which I'm not sure you can do with the MC-E, but you can with a P7. I'll wind the input up to 4A tonight and measure the Vf

4A was 3.6V input. I doubt it would go to 4.2v as I'd imagine it'd pull around 6A