Non-destructive method ‘sees’ EV battery health through metal casings

An international research team from the Helmholtz Institute Mainz and New York University has developed a non-destructive diagnostic method to assess the internal health of rechargeable batteries through their metal casings using zero-to-ultra-low-field nuclear magnetic resonance (ZULF NMR). This technique allows scientists to "see" inside batteries without opening them, overcoming a major challenge since conventional methods could not determine electrolyte condition without destroying the battery. By detecting and quantifying key chemical components such as solvents and lithium salts inside commercial battery cells—including pouch cells used in electric vehicles—the method provides critical insights into electrolyte degradation, a primary cause of battery failure and safety hazards like fires. The ability to monitor electrolyte volume and composition nondestructively has significant implications for battery safety and performance, especially in electric vehicles and renewable energy storage systems. Real-time, operando measurements could enable batteries to self-report issues such as range loss or chemical instability before catastrophic failure occurs. Beyond immediate diagnostics, this approach could advance understanding of electrochemical processes, aiding