Cryo-electron microscopy, an imaging technique that netted three scientists the 2017 Nobel Prize in chemistry, has provided the first atomic-level views of dendrites — whiskery lithium fibers that can spread through lithium-ion batteries, making them short-circuit and catch fire. Until now, scientists couldn’t examine dendrites so closely because the only technique for imaging battery components with atomic-level resolution destroys these fragile filaments, explains study coauthor Yuzhang Li, a materials scientist at Stanford University.
Li and his colleagues flash froze lithium dendrites with liquid nitrogen to preserve their structure before putting them under the microscope. The new pictures reveal each dendrite as a long, needlelike crystal, the researchers report in the Oct. 27 Science. Better understanding dendrite architecture and growth may help researchers devise better ways to keep these fibers from ravaging batteries in cell phones, laptops or electric cars.