The race is on among the world's auto companies to make electric cars go farther on a single charge, bring the price down to compete with gas-powered vehicles, and give drivers more places to recharge them than just the family garage.

Electric is the big buzz at the 63rd Frankfurt Auto Show this week, and nearly every major automaker has at least one on display. Renault
introduced no fewer than four electric models, while Tesla, the only company producing and selling purely electric cars, handed over the keys to its 700th all-electric vehicle, a blue Roadster Sport, to a German buyer at the show.