Achieving a circular economy in the battery industry demands a profound understanding of the degradation behavior of aged battery cells, especially for their potential use in second-life applications. Key to this is the prediction of their future performance and safety characteristics.
However, a significant challenge arises due to the intricate interplay of various degradation modes throughout a cell’s primary life [1][2]. To address this, electrochemical impedance spectroscopy (EIS) is used to deconvolute the complexities induced by early-life abusive conditions in the present study. The tested cells undergo predefined stresses, encompassing deep discharging, high-temperature cycling, and methodological combinations thereof. By utilizing EIS during successive cycling, the relationship of different degradation modes, provoked by specific overstress conditions, will be discussed.
The core objective is to determine if the cumulative degradation behaves as a multidimensional state function. Insights gained from this methodological approach are pivotal for comprehending the degradation dynamics of early-life overstressed batteries, paving the way to their successful incorporation into second-life applications.

Literature:
[1] R. Xiong, Yue Pan, W. Shen, H. Li, F. Sun, Lithium-ion battery aging mechanisms and diagnosis method for automotive applications: Recent advances and perspectives, Renewable and Sustainable Energy Reviews 131 (2020) 110048, https://doi.org/10.1016/j.rser.2020.110048
[2] E. Redondo-Iglesias, P. Venet, S. Pelissier, Calendar and cycling ageing combination of batteries in electric vehicles, Microelectronics Reliability 88-90 (2028) 1212-1215, https://doi.org/10.1016/j.microrel.2018.06.113