rials by up to 400 percent, says Jim Wang, an analytical materials science manager at Sandia. "Electronics designers are Telecosmos: The Next Great Telecom Revolution, edited by John Edwards ISBN 0-471-65533-3 Copyright © 2005 by John Wiley & Sons, Inc. NEW MATERIALS currently forced to use low-power-consumption components and designs that are limited in their longevity," he says. "Our newly discovered anode mate- rials can improve the performance of microsystems by allowing for more powerful, sophisticated electronic components and by reducing the size and weight of the overall system." For years, researchers have been vexed by the capacity limits associated with traditional lithium battery anodes. As a result, Sandia turned to silicon, which offers more than 10 times the lithium capacity potential of graphite but is hampered itself by a rapid capacity loss over time. When small particles of silicon are combined within a graphite matrix, however, large capacities can be retained over time. "The promising aspects of these materials are the large capacities, the capacity retention during cycling compared to other high- capacity materials, and the ability to control its performance by changing the composite composition and microstructure," says Wang. Karl Gross, one of the principal investigators on the Sandia research team, says the silicon-graphite material could be produced via a simple milling process. The production technique is commonplace in the battery industry. In addition, the raw materials needed to produce the material are inexpensive and abundant. The Sandia researchers admit, however, that their new material has some potential vulnerabilities. The biggest obstacle is that complete elimination of long-term capacity fading may not be possible, although it can likely be min- imized by the design of the silicon-graphite composite structure. Yet Wang is confident that silicon-graphite electrodes will set the bar for future break- throughs. "We believe that only other silicon-containing electrode materials 