Acoustic Response Characteristics of Lithium Cobaltate/Graphite Battery during Cycling

Lithium-ion battery (LIB) has become an essential part of various advanced energy storage products due to their excellent performance, but the research on battery degradation is always challenging. The technology of using ultrasound to characterise the state of LIBs has unique advantages compared with other non-destructive testing methods. However, there have only been a few studies on the analysis of battery cycle performance through acoustic response results. In this paper, from the perspective of electrochemical-acoustic field coupling, the ultrasonic count is introduced to characterise the battery state. The acoustic response characteristics of the LIB in the cycling are analysed combined with the conventional acoustic metrics. Based on the continuous fatigue damage model, the acoustic count can infer partial change evolution of the overall effective Young's modulus of the battery. This study shows that the characterisation of the battery state can provide further thinking for the mechanical evolution of the batteries.