1, University of California, Riverside, Riverside, California, United States
3, University of California, Riverside, Riverside, California, United States
Lithium-ion batteries are promising for large-scale energy storage applications due to their high capacity and relatively lightweight compared with conventional Lead-acid batteries. Despite their high promise, current LIBs are limited with reliability and scalability because of the lack of an accurate model to show the real state of health the batteries. Herein, we compressively investigated the internal battery dynamics of bulk, interfaces throughout the frequency range in 18650 lithium-ion batteries by modeling and driving simulation. Specifically, we simulated daily driving situation that the battery experiences in real life by using driving simulation program. We also investigated the degradation of the battery dynamics by EIS spectroscopy, which has been proved to be validated for studying the interfacial dynamics for various electrochemical systems. Finally, we developed a model for battery interface dynamics by using COMSOL modeling techniques to further investigate the interface dynamics of the batteries during the daily driving and aging situations, Butler-Volmer equation for electrochemical kinetics at interfaces, Fick’s law of diffusion and other theories were used to build the model to simulate the experimental results. As a result, accurate SoH model was determined then we also discuss the possible strategies to develop the lifetime of the batteries. Our results provide a broader understanding of the state of health of 18650 lithium-ion battery in particular and lithium-ion batteries in general.