WiredInUSA May 2016

INDEX

Long-life batteries

charging and discharging. The gel makes the nanowires more flexible, which prevents cracking. Mr Penner, who oversaw the experiments of PhD student Mya Le Thai, said the discovery was made by chance. “Mya was playing around and she coated this whole thing with a very thin gel layer and started to cycle it,” said Mr Penner, chair of UCI’s chemistry department. “She discovered that just by using this gel, she could cycle it hundreds of thousands of times without losing any capacity.” “The coated electrode holds its shape much better, making it a more reliable option,” added the student. “This research proves that a nanowire-based battery electrode can have a long lifetime and that we can make these kinds of batteries a reality.”

Batteries with an almost unlimited lifespan could become a reality using a new nanowire-based material. The material, developed by a team from University of California, uses manganese dioxide to protect gold nanowires in a Plexiglas-like electrolyte gel. In tests, the material demonstrated consistent capacity over 200,000 recharge cycles. “These things typically die in dramatic fashion after 5,000 or 6,000 or 7,000 cycles at most,” said Reginald Penner, senior author of a study published in the latest issue of the journal American Chemical Society’s Energy Letters. Gold nanowires have been tried in batteries before, but scientists usually found that the filaments – thousands of times thinner than a human hair – will crack and grow brittle with repeated

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