This one , I thought I'd be cool and try something that, as it turned out, was kinda dumb. I stacked 2 18350s in my mech that had a1.4 ohm dual coil topper. I blew both my
coils and set my throat on fire with one press of the button. The stacked batteries, in my non regulated mech were fresh, and together equalling something like 8.2 volts. I did not enjoy, nor will I ever do again.