Smarter batteries give electric cars a boost

Electric cars hold promise for the environment and have finally begun turning profits for the companies that manufacture them. Still, prospective buyers understandably balk at the initial cost and poor performance of these vehicles. Because electric cars operate on battery power, they can be slower to start, limited in range and less reliable than traditional cars. Recent innovations in battery design and storage may soon eliminate these flaws, however, and make both hybrid and electric cars more attractive.

Electric cars typically run on lithium batteries which must be replaced every three or four years, and replacements don't come cheaply. In addition, batteries often weigh more than standard fuel tanks. The extra weight causes drag and reduces overall efficiency in the cars. Batteries must also be recharged frequently. Considering the number of commuters who travel hours between work and home, few people want to worry about being stranded by the side of the road because they forgot to plug in before heading out.

In the future, cars may be powered by their own bodywork. Researchers at Imperial College London, in partnership with Volvo Car Corporation, are working on a material that is light enough to be used on vehicles and capable of storing electrical energy. Combining the battery with the body work will make vehicles lighter and allow them to travel farther. Researchers estimate that replacing a metal wheel well with a carbon fiber/polymer resin composite could reduce a car's overall weight by 15 percent. The material does not use chemical reactions to discharge energy, which means it will charge more quickly than a conventional battery and will not severely degrade over time. Even better, researchers say the material will be able to charge cars through a household power supply. They hope to further expand the material surface area and enable it to store more energy.

In addition to losing weight and gaining strength, batteries are getting smarter. Researchers at the University of Michigan aim to make use of parked cars. Vehicles spend a majority of their time going nowhere and feeding nothing but meters. Someday the cars might draw energy from the wind or sun and feed it back into the electric grid, thus earning money for their owners while sitting otherwise idle. With funds from the National Science Foundation, researchers are exploring a concept called vehicle-to-grid integration. Large numbers of cars linked to one another would become vast storage units and allow electric and hybrid vehicles to recharge more efficiently and fully exploit renewable energy sources. The stored energy may also help drivers avoid load peaks.

Electric cars need to pull free from the bonds of their batteries. Once these issues are addressed, electric and hybrid vehicles could become truly competitive in the marketplace and encourage more people to enjoy a quieter, cleaner mode of transportation.