ECS-TB Desktop Ultrasonic Scanning Workstation for Non-Destructive Battery Characterization (Max. 300mm*300mm), ETBNDBCDUSW

A desktop ultrasonic scanning workstation represents a powerful frontier in the non-destructive testing (NDT) and structural health monitoring of lithium-ion, sodium-ion, and solid-state batteries. Unlike destructive post-mortem physical teardowns, ultrasonic characterization exploits the relationship between acoustic wave propagation and the physical/mechanical properties of a battery during various states of life and testing.

The system relies on sending high-frequency elastic acoustic waves (typically between 250 kHz and 5 MHz) through the cell geometry using automated X-Y translational scanning stages.

As for the vacuum electrolyte filling in cylindrical cell, a nozzle creates a tight seal around the cell opening, pulls a vacuum directly from the cell interior, and then injects a precise volume of electrolyte. As the acoustic pulse travels through the alternating layers of current collectors, composite electrodes, and separators, its velocity and attenuation change depending on the dense local elastic properties and density of the medium. The workstation captures these changes using two primary operational modes: (1) Transmission Mode (Pitch-Catch): A transmitting transducer on one side of the battery sends a wave, and a receiving transducer on the opposite side captures the attenuated signal. (2) Reflection Mode (Pulse-Echo): A single transducer acts as both transmitter and receiver, measuring the time-of-flight (ToF) and amplitude of waves bouncing off internal structural boundaries. The data is converted into space-resolved mappings: A-scans (1D waveform at a single point), B-scans (2D cross-sectional depth profile), and C-scans (2D top-down areal map of the internal density).

The main applications are typically shown in the following four fields: (1) Electrolyte Wetting and "Unwetting" Mappings: During cell activation (electrolyte injection and vacuum standing), ultrasound maps exactly how the liquid electrolyte spreads across the porous separator and electrode sheets. Areas that are poorly wetted present a massive acoustic impedance mismatch (due to trapped micro-bubbles), showing up as high-attenuation "dead zones." This lets labs optimize formation cycling protocols. (2) Early-Stage Gassing and Side Reactions: Chemical degradation, overcharging, or parasitic electrolyte decomposition generates gas bubbles within pouch or prismatic cell casings. Even trace, invisible pocket volumes of gas completely block high-frequency acoustic transmission. A C-scan map reveals the exact location, shape, and growth rate of gas pockets in-situ during electrochemical cycling. (3) Lithium Plating Detection: When a cell is charged too rapidly or at low temperatures, metallic lithium deposits onto the anode surface rather than intercalating. This alters the local mechanical modulus and creates distinct shifts in the ultrasonic reflection amplitude, providing a precise, non-destructive metric for safe fast-charging limits. (4) State of Charge (SoC) and State of Health (SoH) Tracking: As a battery cycles, intercalation and de-intercalation alter the lattice spacing, volume, and stiffness of the active material layers (e.g., transition metal oxides or graphite). The overall acoustic velocity typically increases near the fully charged state. Over long-term aging, structural degradation like intergranular microcracking or delamination causes permanent acoustic signal degradation.

References:

A. J. Louli, et al., Diagnosing and correcting anode-free cell failure via electrolyte and morphological analysis, Nature Energy, 2020, 5, 693–702.

Z. Deng, et al., Ultrasonic Scanning to Observe Wetting and “Unwetting” in Li-Ion Pouch Cells, Joule, 2020, 4, 2017-2029.

S. Amsterdam, et al., Ultrasonic testing in battery research and production, Joule, 2026, 10, 102402.