Scientists accidentally discover the secret to long-lived batteries
Scientists have discovered technology that could potentially make batteries last hundreds of thousands of recharge cycles, rather than just hundreds.
In the race to make more efficient batteries, scientists would like to pack together tiny nanowires that could be charged many times over. A team from University of California, Irvine, has coated these nanowires with plexiglas-like-gel, and found that they last much longer than other or uncoated nanowire batteries. Researcher Mya Le Thai explains.
Smartphone batteries that decay after too many recharges? Not for long.
Scientists at the University of California Irvine have stumbled upon a technology that could yield batteries that can be recharged hundreds of thousands of times 鈥撀爓ithout any loss to capacity. Their serendipitous discovery, published this week in , came as they investigated how to make nanowire technology less fragile.
鈥淲e were not attempting to extend the cycle life of these electrodes 鈥撀爓e just were trying to prepare a solid state version of 鈥媡hem by substituting a gel electrolyte for the liquid electrolyte,鈥� said paper co-author Reginald Penner,聽.
Scientists have been eyeing nanowire technology's potential for battery improvements for a while. The wires are extremely thin聽鈥撀爐hinner than a strand of human hair 鈥撀犅燼nd great for holding charges.
鈥淗owever, the Achilles heel of such nanowires for energy storage is cycle stability,鈥� explained the researchers in their paper. Despite all the pros, fragile nanowires often grow brittle after repeated exposure to the recharge process in batteries.
And when it comes to current battery technology, poor longevity is already a major issue. A new smartphone can hold a charge all day with juice to spare 鈥� but after 200 recharges, it might need to be recharged before going out for the evening, and after 2000, it鈥檚 best not to stray too far from an outlet.
The typical iPhone lithium-ion battery decays after about , after which it can carry around 80 percent of a full charge, reports the New York Times.
In an attempt to make nanowires less fragile, the lead scientist behind the study, UCI doctoral candidate Mya Le Thai, coated a gold nanowire in a shell and surrounded it with a thin layer of a Plexiglas-like gel, .
The researchers cycled charges through the new composite and were dazzled by the results.
鈥淲e found out we can pass energy through these nanowires ,鈥� Ms. Le Thai said in a video explaining the experiment.
鈥淭hat was crazy,鈥� Dr. Penner said in the press release, 鈥渂ecause these things typically die in dramatic fashion after 5,000 or 6,000 or 7,000 cycles at most.鈥�
Why does it work? The details remain a little unclear, but the gel helps prevent the nanowire from corroding as it receives a charge, say the researchers.
鈥淭he coated electrode holds its shape much better, making it a more reliable option,鈥� Thai said.
For now, lithium-ion batteries that decay after hundreds of recharge cycles will remain the only commercially viable option. The UCI research team was testing nanowire, not producing a nanowire battery ready to be shipped to consumers. But the team remains optimistic about their discovery's prospects.
鈥淭his research proves that a nanowire-based battery electrode can have a long lifetime and that we can make these kinds of batteries a reality,鈥� Thai said.