Title: Structural, Thermodynamic and Kinetic Modeling of Materials for Energy Storage

Speaker: Gopi Krishna "Phani" Dathar, University of Texas at Austin

Date/Time: Wednesday, September 15, 2010, 9:00 am Mountain Time       

Location: CSRI/90 SNL/NM - Videoconferenced to 940/1103 SNL/CA

Brief Abstract: One of the most important challenges faced by our community is to find viable and pragmatic means for renewable energy storage. Current proposed materials to store energy suffer from the unfavorable properties making the transition from lab to market not feasible. Engineering the material properties requires a solid fundamental understanding at the atomistic level, of the structure and reactivity of the materials. Understanding of the kinetics of mass and charge transfer in the bulk, at the surfaces, and interfaces, opens up the possibility of engineering the transport properties of the materials to suit the present day needs and to achieve the intended performance.

My present research addresses the Li ion transport in cathode and anode materials for lithium ion batteries. We focus on developing a micro-kinetic model based on inputs from first principles calculations to understand the charge/discharge kinetics in olivine phosphate (FePO4) and potassium pentaniobate. Methods beyond density functional theory (DFT) are employed to factor in the effects of localized electrons at the transition metal centers in FePO4. Grand canonical montecarlo is used to model the behavior of lithium adsorption at the surface of the material. The standard kinetic monte carlo (KMC) algorithm is implemented to study the behavior of Li ion transport as a function of time and chemical potential sweep. Charge orderings in the lattice, structural arrangements of Li and the pathways for Li ion diffusion are emphasized to describe the charge and mass transport in the materials. My past research includes working on metal hydrides for hydrogen storage with emphasis on predicting the effects of transition metal dopants on the hydrogen binding in the material and computing the favorable thermodynamic and kinetic pathways for hydrogen desorption.

Extending application of theoretical methods in terms of time and length scales increases the accessible phases between experiments and theory, thereby providing a better understanding of design and development of novel materials. The approach in my research interests is to construct micro/macro models with the information derived from atomistic/molecular levels. Emphasis of my research would be to apply computational techniques towards investigating kinetics of mass/charge transfer in electrode materials, nanocomposites, metal-oxides, and across heterogeneous interfaces.

CSRI POC: John Aidun, 505-844-1209, and Rick Muller, 505-284-3669