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Electric Vehicles

Batteries, Advantages, Hybrids, Challenges Still Exist

Electric vehicles (EV), vehicles whose wheels are turned by electric motors rather than by a mechanical gasoline-powered drivetrain, have been long touted as saviors of the environment due to their low pollution and high fuel efficiency. However, they have yet to take over the highways and byways.

Thomas Davenport is credited with building the first practical EV in 1834, which was quickly followed by a two-passenger electric car in 1847, then an electric car in 1851 that could go 20 mph (32 km/h). The Edison Cell, a nickel-iron battery, was developed in 1900 and was a key factor in the development of early twentieth century electric vehicles. By 1900, electric vehicles had a healthy share of the pleasure car market. Of the 4,200 automobiles sold in the United States at the turn of the century, 38% were powered by electricity, 22% by gasoline, and 40% by steam. But by the 1920s, both electricity and steam had lost out to gasoline.

Automakers began working on electric vehicle batteries again during the 1960s as an offshoot of the U.S. space programs. Research continued during the oil embargo of the 1970s, through the 1980s and the 1990s. The results include a handful of commercially available electric automobiles capable of driving between 70-100 mi (113-160 km/h). As of the year 2000, a sample of the EVs on the market include:

  • DaimlerChrysler EPIC Electric Minivan—Range: 80–90 mi (130–145 km/h); Acceleration: 0–60 mph (0–97 km/h) in 17 seconds; Maximum speed: 80 mph (130 km/h); Recharging time: four to five hours (220v)/30 minutes (440v); Battery: nickel-metal hydride.
  • General Motors EV1 uses a lead-acid battery, changing to nickel-metal hydride battery—Range: with a lead acid battery 55–95 mi (90–153 km) and with a nickel-metal hydride battery 75–130 mi (120–210 km); Acceleration: 0–60 mph (0–97 km/h) in less than nine seconds; Maximum speed: 80 mph (130km/h); Recharging time: lead-acid battery 5.5–6 hours and nickel-metal hydride six to eight hours.
  • Nissan Altra EV—Range: 120 mi (193 km); Acceleration: 0–50 mph (0–80 km/h) in 12 seconds; Maximum speed: 75 mph (120 km/h); Recharging time: five hours; Battery: lithium-ion battery.
  • Toyota RAV4-EV-Range: 126 mi (203 km); Acceleration: 0–50 mph (0–80 km/h) in 12.8 seconds (or 0-60 mph [0–97 km/h] in about 18 seconds); Maximum speed: 79 mph (128 km/h); Recharging time: six to eight hours; Battery: Nickel-metal hydride.

Other auto manufacturers such as Ford, Honda, Mitsubishi, Daihatsu, BMW, Audi, Fiat, and Peugeot, are competing to produce a commercially viable vehicle for the masses.

The key components of an electric vehicle include energy storage cells, a power controller, and motors. Transmission of energy in electrical form eliminates the need for a mechanical drivetrain. A special braking design, called regenerative braking, uses the motor as a generator. This system feeds energy back to the storage system each time the brakes are used.

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