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This post, part of a series we're running all about electric cars, was written by Patrick J. Kiger from HowStuffWorks.com.

One paradigm of 21st century life is that each new generation of gadgets is dramatically lighter, smaller, and more energy-efficient and powerful than the old ones we drop off at the recycling center. That's been true of just about everything from PCs to mobile phones to washing machines. But it hasn't been true for cars.

A 2011 Chevy Impala, for example, weighs the exact same 3,555 pounds (1,612 kilograms) as the 1960 version, even though it has more plastic and less steel. Carmakers are bumping up against the weight limitations of those conventional materials. Weight and bulk are a particularly daunting problem for electric vehicles (EVs). The heavier the car, the more battery capacity it needs. And batteries themselves tend to be pretty heavy.

But that may all change, thanks to breakthroughs in nanomaterials, materials composed of incredibly tiny structures that are engineered at a scale of 1 to 100 nanometers. (To understand the scale we're talking about, imagine putting three to five atoms in a line. That would be one nanometer.) By moving atoms around, scientists can fashion materials that are incredibly strong yet light, and have other special abilities as well.

Some production cars, such as the Chevy Cobalt and the BMW M6, already have carbon nanofiber parts, but carmakers could go a lot further. As EV World reported last December, researchers at Germany's [/url="http://tu-dresden.de/en"]Technical University of Dresden[/url] unveiled an experimental single-seat racing car, the E-Wolf e1, designed to show how light a car can be. The E-Wolf is made mostly from carbon nanofiber, which is five times as strong as steel but just a fraction of the weight. The vehicle weighs just 990 pounds (449 kilograms), and most of that weight is batteries (the body panels, frame, interior and other parts come in at just under 400 pounds/181.4 kilograms). Even so, the E-Wolf can hit an impressive 142 miles per hour (228.5 kilometers per hour) on the track. Its range (how far it can go between charges) is 90 miles, which isn't that impressive. But hey, they're working on it.

EV batteries are an even more important application. According to Nanowerk News, NASA is funding research on an experimental lithium-ion battery that contains nanomaterials. This battery could store 50 percent more energy than a battery made from conventional materials. It's intended for use in spacecraft, but it could help extend the EVs' range -- or make it lighter.

But that may be just the start. In the future, a new generation of ultracapacitors fashioned from carbon nanotubes -- instead of the present activated carbon -- may replace conventional batteries altogether. These batteries can provide hundreds of thousands of charge/discharge cycles without degrading. (For more info, read a 2009 ArsTechnica article in which MIT professor Joel Schindall discusses how advanced ultracapacitors might be ideal for powering EVs.)

Meanwhile, Swedish automaker Volvo has been even more ingenious. The company has developed an experimental carbon-fiber car with batteries built in to its roof and panels.