There are additional factors that are application dependent. I'm not sure how much if affects road vehicles, but for aircraft that fact that fuel burns off, mak

There are additional factors that are application dependent. I'm not sure how much if affects road vehicles, but for aircraft that fact that fuel burns off, making the aircraft lighter as the tanks empty is a huge contributor to total range, so you would need to subtract some factor to account for the fact that batteries have a constant mass.