Not sure if this has been asked before, but I searched and couldn’t find anything. So I was looking at a couple flashlight hosts (UF-1504 vs. UF-1405) and I was wondering if there are any advantages for having multiple batteries other than longer run time. I looked at a few graphs and saw something related to forward voltage, but it’s still hazy to me.
It just depends on emitter setup amd how you’re powering it. Most LEDs are 3v so we don’t really need more than 4.2 volts. You can run a single battery on it. The only time multiple cells are needed is if your emitters run on 6v or 12v or of you have emitters in series. Or if you want to run a parallel setup for more runtime. Some lights with a 6v or 12 volt led like xhp70.2 or xhp35 have boost drivers with a single cell configuration and buck drivers or fet drivers for multiple cells.
Not really.
Multiple has increased weight, and issues with cell matching.
If you do not match them, they can reverse-drive a cell causing a fire, or at least damaging that cell.
Attempting to monitor and control matching increases the complexity and cost of charging, if done in the light.
The drivers may be able to run a little more efficiently, but what would that do, raise battery life 3%?
To me, one 18650 is a pretty good compromise for size, weight, cost, lumens and battery life.
wle
Even the lights withulticell setups still run the batteries in parallel (like Sofirn Q8 or SP36). Convoy L6, BLFGT, Imalent RC90, Astrolux MF04 all have series or series/parallel because the emitters need more voltage (and current!). Otherwise, not much benefit besides cost, complexity and weight.