Understanding Lithium Storage in Graphite and Silicon Materials through Computer Simulations

EZEQUIEL P.M. LEIVA; S. CHAUQUE; P. VELEZ; G. LUQUE; A. A. FRANCO; L. URQUIZA; M. OTERO; E. PERASSI; E.M. GAVILÁN; O. CÁMARA; O.A. OVIEDO; D. BARRACO; F. OLIVA

La Haya

Congreso; The 67th Annual Meeting of the International Society of Electrochemistry; 2016

International Society of Electrochemistry

Ezequiel P.M. Leivaa, M. Oteroa, L. Urquizaa, S. Chauquea, E.M. Gavilána, E. Perassia, P. Velez, O.A. Oviedoa, O. Cámaraa, G. Luquea, F. Olivaa, D. Barracob, A. A. Francoca)INFIQC-Fac Ciencias Químicas-UNC-Córdoba-Argentinab) IFEG-FaMAF- UNC-Córdoba-Argentinac) LRCS (CNRS & UPJV, UMR 7314), Amiens, France; RS2E & ALISTORE ERIEze_eleiva@yahoo.com.arRechargeable lithium batteries have become of primary importance due to their technological application in portable electronic devices, and appear as the most promising alternative to drive transportation on the basis of sustainable electricity in the near future. Currently, the market of rechargeable batteries is primarily based on Li-ion batteries and the production is continually increasing. However, to extend their applicability for the future technology, their energy density and capacity must be improved. Therefore, in order to achieve this goal it is necessary to understand more deeply the physical and chemical mechanisms involved in the charge and discharge process and in the synthesis of the possible new materials for electrode. Depending on the problem to be addressed, it is useful to model the system at different scales. For example, while first-principles calculations may be useful to predict equilibrium potentials, semiempirical potentials along with molecular dynamics or Monte Carlo simulations may be applied to understand collective phenomena. In the present work we show in terms accessible to experimentalists how the use of different simulations tools may be useful to analyze different aspects of lithium storage materials. The topics to be addressed in the present talk are:?Use of first- principles calculations to optimize the stability of Si-Graphite nanostructures.?Application of Monte Carlo and Molecular Dynamics simulations to get thermodynamic and kinetic information on the storage of Li ions into carbon-based materials.?Optimization of Si-C composites using coarse-grained models.All the theoretical results will be discussed in the context of experimental results from the literature and from our own laboratory.The previous types of modeling are illustrated in the figure given below. Figure: Illustration of modeling for Li-ion battery materials at different scales. Left: electronic density differential plots by DFT. Center: snapshot of a Monte Carlo simulation of Li insertion into graphite. Right: coarse grained modeling of Si-C composites.