This award supports computational and theoretical research and education that addresses the potential use of solid, rather than liquid or polymer, electrolytes for battery design. Solid electrolytes are thought to be an efficacious alternative to the liquid and polymer electrolytes which may have a greater propensity toward over-heating. The research initially focuses upon well-characterized crystalline systems related to the LiPON electrolytes that have been experimentally developed. Knowledge garnered from these studies is essential for tackling the computationally more challenging task of modeling the glassy forms which have immediate commercial interest in batteries as well as in a number of related technologies. The second research track focuses on the further development of existing computational tools to better model the cathode materials which rely on multivalent transition metals. To address the intrinsic need for 100meV accuracy, the optimized effective potential method will be improved so that the spatial extent of the resulting wavefunctions are devoid of uncertainties associated with the self-interaction error that is intrinsic to standard approximations to the density-functional theory. Use of these wavefunctions in higher level theories improves prediction of energy differences which are directly related to battery power. This initiative is being carried out within a framework that efficiently connects to current efforts to include exact exchange and orbital-dependent approaches to correlation into computational theories that are algorithmically similar to that of density-functional codes. Developments are implemented into at least one standard shared general purpose electronic structure code that is widely used and is part of the cyberinfrastructure of the computational materials research community.
This research may lead to safer batteries with longer life and higher efficiency that are optimized with respect to power-weight ratios. The research will also provide general improvements to the state of computational materials science and aid in training the next generation of scientists through the educational initiatives.
NON-TECHNICAL SUMMARY:
This award supports computational and theoretical research and education that will apply computers and advanced theories and models of materials to aid in the detailed understanding of materials for battery technologies and in the discovery and design of new materials.
The need for portable rechargeable batteries is rapidly growing in a wide variety of applications and correspondingly, there is growing incentive to develop cost-effective and reliable battery technology. While economics, experiment and marketing continue to contribute to successful battery designs, such technological approaches can grow further from new insights gleaned from basic research resulting from previously unavailable computational methods. This initiative employs two research tracks with a goal toward enhancing basic understanding of materials related to modern rechargeable batteries through detailed computer simulation. The first research track uses a variety of computational techniques to study the structures, ionic conductivity, and stability of solid electrolyte materials. The second research track focuses on the further development of existing computational tools to better model the cathode materials which rely on multivalent transition metals
