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To allay consumer misgivings about electrics' high cost and questionable performance, marketing experts say U.S. auto companies must develop more sophisticated batteries. Besides packing exceptional power, the ideal battery should be as light as possible, since minimizing a vehicle's weight improves its performance.
In January 1991, Detroit's Big Three formed the United States Advanced Battery Consortium (USABC) to help them meet California's 1998 emissions-free deadline (see p. 589). The consortium's long-range goal is battery power that gives electric vehicles the performance characteristics of comparable gasoline-fired vehicles.
However, the battery project “bogged down almost immediately” as the corporations haggled over their individual legal rights, Automotive News reported in March.# The authoritative weekly editorialized that the sluggish start could prove costly, since automakers will have to “commit their 1998 electric models to a battery of certain characteristics” by next summer at the latest. However, the tabloid asserted, “It looks unlikely that the USABC will have contributed anything by then, except providing inspiration for independent companies to compete for a solution.”
One such independent is Electrosource Inc., of Austin, Texas, which produces lead wire and conducts research and development for lead-acid batteries, the type found in most passenger cars. Electrosource is now working on an improved lead-acid battery that it says will have double the capacity and useful life of a conventional lead-acid model, take only one-fourth as much time to recharge -- and cost less besides. The key, says Electrosource electrical engineer Rick Blanyer, is the composition of the lead electrode. Instead of the typical car battery's solid lead plates, Electrosource uses screens of lead wire woven in textile fashion around a fiberglass core. Tests have shown that this configuration makes the battery last longer and enables it to store more power. By trimming the overall lead content, moreover, mesh reduces the battery's weight.
According to Blanyer, Electrosource has “the potential for making a battery from raw pig lead in less than four hours” -- a small fraction of the time required in a conventional lead-acid battery plant. Moreover, the Electrosource battery “has no free liquid in it, so there's no chance of spillage. And you never have to add anything to it, because it's sealed.”
Electrosource hopes to have a pilot plant in operation by the end of this year. It is being built with financial assistance from the Electric Power Research Institute (EPRI), an organization of the electric utility industry. Blanyer reports that the plant will not be large enough to supply the total needs of even one major customer. However, the company plans to enlarge production capacity once the size of its potential market becomes clearer.
Other types of batteries also show promise. One is the nickel-iron model developed by Eagle-Picher Industries Inc., of Cincinnati. The nickel-iron tandem provides both high energy and extended life, though its slow-charging is a drawback and needs improvement.
Nickel-cadmium batteries have no such shortcomings. They are prized by Japanese automakers for their longevity, large capacity and quick recharge time. American manufacturers are less enthusiastic, since cadmium is not only expensive but also highly toxic. Widespread use of nickel-cadmium batteries would necessitate costly disposal procedures to minimize damage to the environment. The sodium-sulfur battery, developed by Ford in the mid-1960s, has a similar good news-bad news profile. On the positive side, sodium and sulfur are abundant, cheap materials that yield large doses of energy when yoked together as an automotive power source. The difficulty is that they do so only in a molten state, which they reach at temperatures above 600 degrees F. Consequently, sodium-sulfur batteries require high-performance thermal insulation that adds to their weight, bulk, cost and complexity.
A longer-range possibility for powering electric vehicles is the lithium-metal sulfide battery, originally developed by Argonne National Laboratory in the early 1970s. The U.S. Department of Energy, EPRI and USABC are all currently working on this technology. According to USABC, lithium-metal sulfide batteries could help it reach its ultimate objective -- electric vehicles that match the performance of gasoline-fired cars.
Further advantages of the lithium-metal sulfide battery, in the consortium's view, are its relatively small size and weight, long life, a low cost-per-kilowatt-hour similar to today's most inexpensive batteries, and low manufacturing costs. In addition, the battery is composed of materials that pose little threat to the environment and in fact may be completely recyclable.
Lithium-polymer batteries, also being promoted by USABC, have similar properties. However, neither battery is likely to go into commercial production until the second decade of the coming century.
Some researchers feel quicker results could be obtained by turning to the flywheel, a simple device attributed to the 18th-century Scottish inventor James Watt. A flywheel is a rapidly whirling disk or wheel whose weight is concentrated at the rim. Once activated by electricity from an outside source, the wheel tends to keep spinning. As it does, it produces kinetic (motion) energy similar to the chemical energy stored in a battery. The kinetic energy can then be drawn off to run an automobile.
Researchers say a set of lightweight 9-inch flywheels in a vacuum housing might extend an automobile's range to 400 miles between chargings. To achieve such performance, roughly comparable to that of a gasoline-powered car, the wheels would have to spin at about 200,000 rpm. Low-friction magnetic or liquid bearings could help them reach that ultra-high velocity.
Vehicles propelled by sophisticated batteries or flywheels are not likely to become commercially viable for at least several more years. # “Big 3 Battery Co-op Is Tangled in a Maze of Red Tape,” Automotive News, March 15, 1993
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