Thanks for the science friend. I'm running it on my Dimitri clone. So it's two batteries parallel. Not sure about the maths though. But the vape is surprisingly a decent cool cloud pusher, lol. Right now the volts are at 3.93 and between 3.35 to 3.26 under load.
Doesn't really matter how many batteries you have in parallel, other than, for our purposes, the available maximum continuous current discharge (MCCD) and mAh are compounded.
The arrived at values are based on the Ohm's law formula for wattage, at the fully charged battery constant of 4.2v... which drops as the batteries are discharged.
When fed into Steam Engine, along with the build particulars, the applied wattage provides the heat flux value. Heat flux represents the coil radiated heat value, expressed in milliwatts per millimeter squared.
If you've not used Steam Engine, you'll find it, along with a SE user guide, in the links below.
Cheers