Electric cars have been the future of transportation for nearly a century, and despite a flock of new entries, the battery-powered segment of the auto market remains a narrow niche.

Few transportation technologies provoke as much debate as electric vehicles. Fans love them for performance—a well-designed electric car can accelerate faster from a stop than many a muscle car—as much as for cleanliness. Skeptics ask why they should pay a premium or subsidize tax breaks for cars with limited range and utility.

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