Mapping Performance Variations to See How Lithium-Metal Batteries Fail

Scientists from Brookhaven National Laboratory (Upton, NY) 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.