Lighter and cheaper: The promise of silicon-air batteries

Scientists at the Technion-Israel Institute of Technology have developed a silicon-air battery they say can supply power for thousands of hours without needing to be replaced. The findings are published in the October 2009 issue of Electrochemistry Communications.

They say such batteries would be lightweight, have an unlimited shelf life, and have a high tolerance for both humid and extremely dry conditions. Potential uses include medical applications, sensors and microelectronics structured from silicon.

Silicon-air batteries would provide significant savings in cost and weight because they lack the built-in cathode of conventional batteries. The cathode in silicon-air (and metal-air) batteries is the oxygen that comes from the atmosphere through the membrane.

Chief developer Prof. Yair Ein-Eli estimates that in three to four years, silicon-air batteries can be made more powerful, as well as rechargeable. In 10 years, he says, it may be possible to build “electric car batteries made from silicon that will turn into
sand that would be recycled into silicon and then into power again."

Ein-Eli says there have also been attempts to upgrade such batteries for use in electric cars and portable electronic devices, and that interest in the matter was sparked recently when Toyota and Panasonic began joint efforts to adapt the zinc-air battery for future electronic cars.

More info is on the American Technion Society site:

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