Accidental discovery could help batteries last years longer

Today, most smartphone and device batteries are made from lithium and slowly lose capacity over thousands of recharges. Researchers at UC Irvine built a battery that substituted gold nanowire in electrolyte gel for the lithium and lost barely five percent battery capacity over 200,000 charge cycles — but they aren’t totally sure how it worked.

The researchers were hunting for an alternative to lithium, whose liquid state helps conduct charge but is combustible and sensitive to temperature. Nanowires have been a long-theorized dream battery material as their high surface area holds a lot of electric charge, but wire corrodes in traditional lithium environments after several thousand cycles.

The researchers discovered how to prevent that corrosion while fiddling with different materials. They coated the gold nanowire they were using in manganese dioxide and swapped the lithium for electrolyte gel. The gel and oxide fused into a protective sheath around the wire, and voila: the experimental battery completed hundreds of thousands of cycles over a period of three months with no detectable degradation.

Of course, even the tiny amount of gold wire used was expensive. While they haven’t tested it yet, the researchers suggest nickel as an adequate substitute should the concept reach mass production.

Source: Popular Science

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NASA pours $67 million into solar electric spacecraft engines

NASA is big on solar electric propulsion (the Dawn spacecraft uses it, for instance) for a good reason: while the engines aren’t powerful, they supply thrust for a very long time before giving up the ghost. And it now looks like the agency is ready to double down on that super-efficient tech. It just awarded a $67 million, 3-year contract to Aerojet Rocketdyne in hopes of developing an advanced solar electric propulsion system. The new technology could deliver twice as much thrust, and would be up to 10 times more efficient than chemical engines — both big deals for deep space missions.

So long as the project pans out, it could be crucial to some of NASA’s most important missions. It’ll power the robotic side of the Asteroid Redirect Mission, and should also help in the quest to put people on Mars. Whatever money NASA invests now might pay dividends if it gets ships out to far-flung locations relatively cheaply and quickly.

Via: TechCrunch

Source: NASA

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