In Line Phased Array Inspection of Encapsulated Battery Structural Adhesives
Inline phased array testing maps structural adhesive wet-out and void formation through metal pack enclosures in real time at production line speeds.
Time of Flight
Meaning
Temporal measurement quantifies the interval between the emission of a signal and its return to a receiver. In ultrasonic testing, time of flight provides the raw data needed to determine the depth of internal features or the thickness of layers. Precision in this measurement is critical for identifying the exact location of a flaw within a battery cell.
Distance Calculation
Speed of sound in the specific material is multiplied by the recorded duration to find the travel path. When the time of flight is known, a system can map the internal geometry of a pouch cell with high accuracy. Short intervals indicate reflections from surfaces close to the sensor.
Wave Propagation
Environmental factors like temperature change the velocity of the signal and must be compensated for during the test. A shift in the time of flight often signals a change in the physical state of the battery, such as the transition from a liquid to a solid during electrolyte curing. Sensors must resolve nanosecond differences.
Material Characterization
Analyzing how the duration changes under different state-of-charge conditions reveals information about electrode expansion. As the battery cycles, the time of flight varies because the density and thickness of the layers shift. This relationship allows researchers to monitor the internal health of a cell without opening the casing.
Advanced diagnostic tools use these temporal shifts to predict the onset of lithium plating or other degradation mechanisms. The data provides a non-invasive window into the electrochemical activity occurring inside the sealed unit.