Thermodynamic and kinetic modeling of lithium insertion in graphite-Comparison with experiment

LEIVA; GAVILÁN ARRIAZU, E. M.; ALEXIS PAZ; A. OVIEDO; OSCAR PINTO; MANUEL OTERO; BARRACO DÍAZ, D.E.

Durban

Congreso; 70th Annual Meeting of the International Society of Electrochemistry; 2019

International Society of Electrochemistry

Lithium-ion batteries are nowadays the most commonly used energy storage devices, with graphite being the material used preferably as an anode. During Li-ion loading and unloading in a graphite anode, it is well known the existence of stable structures called "stages", which can be observed by different types of experimental measurements. The lithium intercalation process in graphite it is still studied exhaustively, because some of its basic features are a matter of discussion. Besides refined experimental studies, theoretical simulations can provide answers to some of these questions. For example, although numerous experiments have been performed, the detailed features of Li ion diffusion in graphite cannot be unambiguously assessed. Something similar can be stated on the behavior of the partial molar entropy in these systems, for which modeling is relatively recent.In the present talk we address, by means of theoretical tools and computer simulations the thermodynamic and dynamic behavior of lithium storage in graphite, in close comparison with experiments. With this purpose, an effective Hamiltonian is proposed and Statistical Mechanics, Grand Canonical Monte Carlo and Kinetic Monte Carlo simulations are employed to obtain thermodynamic and dynamic information on this system.