Acoustic testing (typically in the ultrasonic frequency range) sends sound waves through the cell and detects internal changes based on wave propagation patterns. Acoustic testing has many advantages, particularly its sensitivity to low-Z components such as electrolyte—making this technique well-suited for evaluating electrolyte wetting. However, one notable limitation is its poor spatial resolution (typically on the order of millimeters).
- Pros: Nondestructive, fast (~seconds to minutes), spatially resolved, and sensitive to low-Z components such as separator and electrolyte.
- Cons: Low resolution (typically ~mm).
References
- Yuankai Ren, Ming Huang, Genlin Liu, Yun Zhao, Billy Wu, Yatish Patel, Frederic Cegla, Bo Lan, Decoding coupled mechanical–electrochemical responses in multi-layer batteries via generalized ultrasonic dynamics, Energy Storage Materials, Volume 82, 2025