share: Mapping Performance Variations to See How Lithium-Metal Batteries Fail Using high-energy x-rays, scientists probed different points across a high-energy-density lithium-metal battery—of interest for long-range electric vehicles—and used the data to identify the main failure mechanism April 19, 2021 Brookhaven Lab chemist and Stony Brook University (SBU) professor Peter Khalifah (middle) with SBU graduate students Zhuo Li (left) and Gerard Mattei (right) holding a "pouch cell" battery attached to a frame used for synchrotron x-ray studies. Note: This photo was taken prior to current COVID-19 social distancing guidelines. UPTON, NY—Scientists have identified the primary cause of failure in a state-of-the-art lithium-metal battery, of interest for long-range electric vehicles. Using high-energy x-rays, they followed the cycling-induced changes at thousands of different points across the battery and mapped the variations in performance. At each point, they used the x-ray data to calculate the amount of cathode material and its local state of charge. These findings, combined with complementary electrochemical measurements, enabled them to determine the dominant mechanism driving the loss of battery capacity after many charge-discharge cycles. As they recently reported in