it also dempends on if someone has coded for it to be used as a controller module, there are a lot of files alread out there for esp32, and it is like $5 for one.
I never have spare 18650's, just a bunch they have gone bad, won't charge, or barely hold charge. I use the light purple Samsung ones in my vape, they seem to last longer for me.
i recently got some really good 3500mah 18650's out of a tossed portable oxygen machine. only one cell had went bad out of the 8. they all hold around 3450mah on adischarge test.