A methodology for analyzing aging and performance of lithium-ion batteries: Consistent cycling application

Abstract Lithium-ion batteries are consistently cycled and characterized using the Degradation-Entropy Generation (DEG) methodology. Irregular and abusive cycling was recently published in the literature. Here, DEG capacity fade is compared to Coulomb-counted capacity fade, and DEG elements—DEG coefficients Bi, dissipation factor J, entropic efficiency ηS—are evaluated and interpreted for battery performance and degradation analyses. The effect of cycling rate (C-rate) on the DEG elements is discussed using measured data from three same-model lithium-ion batteries discharged at different C-rates. The results and features of the DEG methodology accord with established lithium-ion battery behaviors and the laws of thermodynamics, rendering the approach easily adaptable to battery analysis.