When you send a rocket into space, you run into a paradox: Around 90% of the weight of the rocket is the fuel that it needs to lift away from Earth. As the rocket accelerates, three things happen: The speed increases, the rocket gets further away from Earth (and from the gravitational pull of the planet), and as the fuel burns off, the rocket weighs less and so can accelerate faster.
We face a similar problem in the world of EVs, with an obvious exception. Technically, car batteries get heavier as they are charged, but the difference is so small that you couldn’t measure it even with the most precise car scale. However, that doesn’t matter, because when you add more batteries to a car, it must always carry all those batteries. That’s a problem that’s growing bigger as cars themselves get bigger and heavier.
A 1984 Volkswagen Rabbit only had 90 horsepower, but its average fuel economy was 34 miles per gallon. The 2009 version of that car had almo …
