Word around Detroit is GM and the EPA are apparently duking it out over the Chevy Volt. The problem is this: Is the Volt an electric car, or a hybrid? How you define the Volt is important, because it dictates how the official EPA fuel economy numbers will be calculated.
Strictly speaking, the Volt is a hybrid in that it is an electric vehicle with an on-board internal combustion engine (likely a version of GM's 1.4L Family Zero four). The internal combustion engine, which is connected to a generator, acts as a range extender when the Volt's lithium-ion battery pack runs low on power.
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