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Physics

Energy Density

Quick fact

Gasoline has about 34 megajoules per liter, while the best lithium-ion batteries store only about 2.5 megajoules per liter — over 10 times less.

Why this is interesting

Why does a gasoline tank give your car hundreds of miles of range, yet a battery of the same size barely gets an electric car a fraction of that? The answer lies in a hidden property: energy density.