Ultrasonic Non-Destructive Testing on Fast-Charging Lithium-Ion Battery's Capacity Fading

Fast charging technology provides a solution to the issue of charging time for power supplies with long life requirements. However, it will shorten the charging period while also hastening the power battery's capacity degradation, reducing its service life. The ultrasonic inspection technique has been widely used for the internal structure detection and reaction process characterisation of lithium-ion batteries because of its nondestructive testing properties. This paper presents a method for monitoring the capacity attenuation of a fast-charging battery by calculating the ultrasonic attenuation coefficient alpha. The experimental findings indicate that the battery's capacity is more vulnerable to lithium plating during high-rate charging. The parameter alpha can be employed to illustrate the energy dissipation characteristics of sound as it propagates through the electrode. Moreover, the inhomogeneous ageing of battery electrode material is observed and quantified based on the differences in acoustic signals, which provides new insights into battery health management and uneven ageing assessment. Acoustic response about temperature, charging rate, and number of cycles' effects on lithium deposition.Power function relationship between acoustic attenuation coefficient and capacity fading.Observation of inhomogeneous aging of cells using local acoustic signals.