Energy Forum / Alternative Energy

Americans may be ready to embrace the electric car, but can the technology catch up?

It has taken a long, long time, but financial chaos, environmental concerns, and wild gyrations in oil prices—along with $2.4 billion in government funding—may finally bring practical electric cars to the American market. Virtually every major automaker is preparing to sell a battery-powered vehicle over the next few years. But a big question remains: Will battery technology finally be good enough to take the place of gasoline? Engineers see three ways it could happen.

Refining the Battery
A successful automotive battery must provide long driving range from a single charge and release its energy quickly enough for brisk acceleration. Lithium-ion batteries—similar to what powers your laptop or cell phone—satisfy both requirements, making them a big step up from the nickel-metal hydride cells used in gas-electric hybrids like the Toyota Prius. But the technology still has limitations: It is costly, it delivers about 1/40 as much energy per unit weight as petroleum, and if overheated or overcharged, it could burst into flames.

Nevertheless, it exists today, and carmakers are putting money into some 14 improved designs that should make lithium-ion batteries smaller, safer, and more efficient. One line of research adds manganese or iron phosphate to the technology, increasing energy capacity while protecting against runaway heating. Stanford University scientists recently showed that embedding silicon wires in batteries could increase their storage capacity tenfold, while researchers at MIT have reengineered the battery material to allow much faster charging. If these innovations make it to the market, plug-in cars like the Chevrolet Volt could recharge in minutes instead of hours and drive 400 miles on a charge.

But it will take time for such advances to make their way into the extreme environment under the hood. Price could also present a barrier. A recent Carnegie Mellon University study suggests that hybrid plug-in vehicles would be more expensive over a lifetime of use than comparable gas-powered cars due to the battery’s hefty cost. For instance, the Chevy Volt’s 200-lithium-cell battery pack would cost about $16,000, according to estimates.

Banking on the Breakthrough
A truly successful electric car may need significantly better electricity storage technology. Toyota has shown interest in metal-air batteries, which store electricity from zinc or aluminum reacting with oxygen. Metal-air would offer far greater range than lithium-ion, but it is not rechargeable with simple electric current, so drivers would have to clean out the battery regularly and replenish it with metal “fuel.”

A more fundamental breakthrough could come from switching to capacitors, devices that use electric fields to trap electrons. Although capacitors cannot store as much energy as batteries, they are far better at releasing rapid pulses of electricity (for fast acceleration) and collecting electricity (recovered during braking, for instance). Engineers are experimenting with dual systems of batteries and capacitors that capitalize on each system’s strengths.

Sticking to the Infrastructure
Given the shortcomings of both batteries and capacitors, some engineers say the true solution lies in better infrastructure: They want to make electric-charging spots as ubiquitous as gas stations.

One proposal comes from Better Place, a company that envisions a system in which consumers would pay a fee to get access to a national network of plug-in parking lots and automated exchange stations that would swap out a rundown battery for a fresh one, providing a quick fix. Israel has already signed on to create such a network.

For now, automakers are jousting to develop as many electric vehicles as possible and seeing what sells. Ahmad Pesaran of the National Renewable Energy Laboratory predicts that over the next decade lithium-ion will rule. GM, Ford, Nissan, and Mercedes are developing lithium-battery vehicles; even Toyota, which has had tremendous success with its nickel-battery Prius, is set to release a lithium-ion version later this year. Of course, all that could change quickly—as happened at the turn of the 20th century, when the quiet, reliable electric car, powered by primitive lead-acid batteries, seemed destined to sweep the market. Instead, Henry Ford’s gasoline-powered Model T transformed the industry, enabling lower cost, longer distances, and higher speeds. History may yet repeat itself. “These are all big, expensive bets,” says Ted Miller, senior manager of energy storage strategy and research at Ford. “I guess you have to have a little bit of a gambler’s mentality.”