Running the LEDs at low currents for high lm/W and using high quality optics isn’t a problem, that’s easy to test and sort out.

We just need to figure out which drivers we can use to get high efficiency while the battery voltage is far above the LED voltage, such that it can stay in regulation.
If the battery is fully charged at 4.2, and an LED is running at ~200lm/W at 2.7V, that’s a 1.5v delta.

Maybe we need more people to do driver tests :question: