Researchers from Northwestern University say they’re working on developing a super-battery that can keep a cellphone charged for a week and be recharged in just 15 minutes – but making small electronics a little more convenient is only the beginning of their ambition. They think the technology also might make for far more efficient and smaller electric car batteries.
According to the university, the breakthrough in developing lithium-ion batteries that can hold a charge 10 times longer than current batteries has come by addressing both energy capacity and charge rate. The capacity was jacked up by sandwiching clusters of lithium-accomodating silicon between the graphene sheets of the anode. “This allowed for a greater number of lithium atoms in the electrode while utilizing the flexibility of graphene sheets to accommodate the volume changes of silicon during use,” the university said. Then to speed up charge rate, the team used a chemical oxidation process to create “in-plane defects,” which is a fancy way of saying tiny holes (really tiny; like, 10 to 20 nanometers wide). These gave the lithium ions a shortcut, the university said, into the anode, where they could be stored by reaction with silicon.
“We have found a way to extend a new lithium-ion battery’s charge life by 10 times,” said Harold H. Kung, lead author of the paper. “Even after 150 charges, which would be one year or more of operation, the battery is still five times more effective than lithium-ion batteries on the market today.”
But don’t pull out your wallet to buy the batteries just yet. Researchers say the technology is still anywhere from three to five years from being on the market. To read more about exactly how the new technology works, the research paper is available for purchase through Advanced Energy Materials.