The difference between turbocharging and supercharging is simple: a turbocharger boosts engine air pressure by using exhaust gas to power a turbine that pushes more air into the combustion chamber.

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So, crawling out on a limb, he asked BorgWarner's strategy board for funds so that he and a small group of engineers could begin work on a new turbocharging system that would draw its power from the supersize battery instead of the car's exhaust system.

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