215 / 2025-06-14 16:40:18

Spectral Characterstics of Active Wide-band Acoustic Emission Signals for Lithium-ion Battery Monitoring

Lithium-ion batteries (LIBs), Acoustic diagnostics, Material characterization, State of Health (SOH)

The performance and safety of lithium-ion batteries (LIBs) are critically dependent on dynamic structural and interfacial changes within their constituent materials (electrodes, electrolyte, separator) during electrochemical cycling. Understanding the evolution of material microstructures and interfaces, particularly as a function of State of Charge (SOC) and State of Health (SOH), is essential for advancing Battery Management Systems (BMS). This study introduces a novel non-destructive method for inspecting LIB material properties based on active acoustic interrogation and spectral analysis. The approach involves transmitting swept-frequency acoustic waves into both purpose-designed 3D-printed samples (with controlled parametric variations) and operational pouch cell LIBs, followed by detailed analysis of the resulting acoustic emission signals. Spectral features extracted from these signals demonstrate distinct correlations with specific material conditions in both sample types and pouch cells. These findings establish a new frequency-domain framework for precise battery diagnostics, enabling the potential visualization of dynamic material property changes throughout the charge-discharge cycle.