Electrical Path/Resistance Question

[jaundice]

I've read on other threads that adding cell extensions to a flashlight body raises the resistance of the circuit, making it less efficient. Apparently the joint between the cell extensions is a gap in the circuit. My question is, how much resistance is added to the circuit? How much efficiency is lost?

I have a fivemega 1x16340 that I want to run as a 2x16340 by adding a cell extension. How much, percentage-wise, am I losing by doing this, versus using a unitary 2x16340 body?

Thanks,

-John

 

[SemiMan]

If you regularly lubricate the threads with a good electrical contact cleaner, I think realistically, the loss will be very very low, i.e. 1% or less.

Semiman

 

[2xTrinity]

Resistance added by having a threaded extender will likely be less than 10mOhm if the interface is clean. Seeing as you're using 16340s, you will most likely be working with currents less than 1A.

If so, you will drop V = I*R = (1 amp) ( 0.01 ohms) = 0.01 volts, out of 7.4

or 1/6th percent. If your light runs at less than 1 amp, you will lose less than that.

The point where this sort of resistance becomes relevant is for hotwire mods, where currents closer to 10A are not uncommon. There even a low resistance of mOhm can represent a few percent loss in power.

 

[jaundice]

Thanks for the responses, this is exactly what I was looking for!

-John