"Multiscale Capabilities for Exploring Transport Phenomena in Batteries": Ab Initio Calculations on Defective LiFePO 4
We have began the project “Multiscale Capability for Exploring Transport Phenomena in Battery”, which is sponsored by Laboratory Directed Research and Development Program at Lawrence Livermore National Laboratory in February 2012 as the subcontract was approved. We have been performing first-principles quantum-mechanical calculations to first establish the general modeling framework. It was found that it is essential to employ advanced Density Functional Theory (DFT) calculations with Hubbard U correction, in order to describe the battery material, in particular, LiFePO4 (Figure 1). The presence of localized d-electrons at Fe ion sites requires the better treatment of non-local correlation beyond that of standard DFT. As our aim was to first identify and investigate key transport/reaction mechanisms affecting the performance of Lithium-ion based batteries, we have began out work by characterizing the standard structures and how the defects influence the important electronic structure.