The Electrovair II, built in 1965 (and often cited as a '66 model) was on the even flexier, new four-door hardtop Corvair body. It was painted Bill Mitchell's favorite bright metallic blue, with 60-spoke Dayton wire wheels and knockoffs, and Lucas Flamethrower high-beam headlamps. The silver-zinc batteries cost a total of about $160,000 in '66 dollars. At 532 volts, its 115-horsepower AC induction motor and solid-state controller gave the Electrovair II a 40-80-mile range. Top speed was 80 mph, and it could do 0-60 mph in 16 seconds.

At about the same time, GM built the GMC HandiVan-based Electrovan with the same solid state engineering and drive motor as the Electrovair II, but with a Union Carbide cryogenic fuel cell subbing for the less costly silver-zinc batteries. For reference, the fuel cell was an earlier version of the unit developed for the command module of Apollo moon rockets, including Apollo XIII. GM built a fueling bunker for the project at the Warren Tech Center.

GEN 2:No, it's not a Corvette body. Electrovette was a Chevrolet Chevette with a battery pack replacing the rear seat. GM Advanced Engineering developed the car with plans to force it on the Chevrolet division. The motor was mounted about where the Chevette's transmission was. The induction motor and planetary drive routed 50 kilowatts to the rear wheels. It had a range of about 50 miles at 30 mph using lead-acid batteries. Zero to 30 mph took 8.2 seconds. GM thought the zinc-nickel oxide batteries it was developing would have doubled Electrovette's range. The two-passenger prototype weighed 2950 pounds, though a production model planned for the early '80s would have had a shortened Chevette wheelbase.

GEN 3:GM's EV1, derived from the Santana project car, became the Impact concept. The Santana/Impact used two motors (one for each front wheel) driving through a MOSFET (metal oxide silicon field-effect transistors) inverter/controller, not the stuff of production viability. That evolved into the EV1, arguably, for its time, the most advanced production-compliant electric vehicle with the world's worst battery -- lead-acid. GM leased out 800 of them in Phoenix, Tucson, and Los Angeles from 1996 to 2003. Toward the end, GM experimented with a natural-gas-fed 1.0-liter turbocharged three-cylinder using the EV1/Impact's lightweight body. Its emissions were lower than those calculated for an EV1 running on electricity generated from fossil fuels.

GEN 4:Success, finally. The Chevrolet Volt uses lithium-ion battery technology. And it'sMotor Trend's 2011 Car of the Year.