Have you thought about developing flashlights with dual diodes and dual batteries? For example 2*LH351D/2*14500 or 2*50XHP/2*21700 and many other options.
I have already seen many such inexpensive flashlights on Aliexpress, apparently there are factories that can make such cases from aluminum at an affordable cost.
Well, the below example is same light same distance, both lux meters are brand new. I have measured against the Extech another 6 light meters (less and more expensive) and all are measuring minimum 20% higher, nevertheless none of them measured as high as the Uni-T. And the funny thing is, that the laboratories I managed to find are proofing the lux meters, but only with standard light source (not LED) only up to 1000 lux, while the Ex-tech only has data for LED. Measuring lumens is easy with Maukka lights, but throw is confusing for me with such differences. Any ideas how can I narrow down the results?
I got the same L21B (CSLNM1.TG, 12-group driver) and the driver looks similar to the one in your picture.
Using UT210E clamp meter, and with a fully-charged 21700 battery, I measured up to 5.4Amps tailcap current (not 6 Amps).
I'm not sure if this is the 5Amp or 6Amp driver. The box label indicates "5A 12-group" though.
Beamshot of the Convoy L21B (Osram CSLNM1) (5 Amp driver? - although I measured around 5.4 Amps max tailcap current when using a full charge battery)
for reference, this is the how the scene looks during daytime
I measured this with my UNI-T 383S:
1488 x10 lux L21B CSLNM1 at 6m = 535680 cd
Throw: sqrt(535680 cd x 4) = 1463m
And Manker for reference;
4831 lux MC13 White at 6m = 173916 cd
Throw: sqrt(173916 cd x 4) = 834m
Distance and height could be off by +/- 10cm when placing the flashlight at one end of the room and taking the measurement. I used Max mode and moved the beam across the sensor.
The distance is critical and does vary the numbers quite a bit. I get 155,800cd from my MC13. So yours is either performing really well, or your numbers a little high (or mine low)
As far as I know, the Convoy L21, be it B or A, uses a ∅22mm driver. Then, the ∅22mm “SST40” drivers (12-groups, 2-modes, 4-modes) claim up to 6A of output current, i.e. they should limit current exactly to a maximum of 6A.