If I wire 2 batteries in series the output would be approx. 7 volts to the buck, The voltage and current will be limited by the buck to 3.7v and 2000ma as measured with a multimeter (which I didn’t want to buy but since the buck is adjusted with a POT is seems this is required.) Then the LED’s follow the buck in parallel.
Just need a switch, and probably a heat sink.
Let me know if I should repost in another part of the forum.
I can vouch for those LM2536 modules, I use them to charge my daughters 6vdc power wheels lead acid battery by regulating the voltage to 7.2vdc from a converted 400 watt ATX powersupply on the 12vdc rail (2.4vdc per cell) and then running it thru the ammeter on my multimeter, shut it down when the draw hits 3% of the 4AH (4000mAh batterys) so 120mA
They are current regulated, hit about 3.2~Amps at max…but the chip gets CRAZY hot…I even put a heatsink on it and that gets hot too
They are buck circuits though…you have to put at least 2vdc higher into it, it’s not a boost/buck circuit LM2596 spec sheet
Ah I see you are going to regulate the series Li Ion down to 3.7vdc and feed two XM-L2’s in parallel…yeah that will work, but have to be careful the volts could drift without a full time output voltage measurement…those pots are pretty cheap, and there is no low voltage protection other than what is on the batteries…if they fail, you kill the cell
You don’t have to have a seperate multimeter, just add one of these .36 display voltmeter modules on the outputs, it will read down to 3~ vdc
Disregard the boost/buck unless you are looking for something like that
