Atomistic simulation methods for ion conduction in battery materials

This PhD project will apply highly accurate atomistic simulations on materials and interfaces involved in state-of-the-art battery technologies, to understand how the properties of these complex materials can be tailored to improve battery performance. Specifically, the ion transport properties and the link between material chemistry and battery performance will be explored in detail.
An essential tool for this task are quantum mechanical calculations from first principles which provide a very accurate description of materials. Conventionally such calculations have been limited to a few hundred atoms at most because the computational effort associated with first principles quantum methods such as Density Functional Theory (DFT) scales as the third power of the number of atoms and is computationally prohibitive. Recently this situation has started to change due to the ever-increasing power of supercomputers and new developments in theory such as linear-scaling DFT and in particular the ONETEP program for linear-scaling DFT which will be used for this project as it is capable of calculations with thousands of atoms and retains the near-complete basis set accuracy of conventional DFT.
A prominent role in this work will be played by recent and ongoing developments in ONETEP with novel highly accurate exchange correlation methods, advanced solvent models, and fast configuration sampling techniques. These quantum methods will be further developed and validated in test cases involving battery materials. Examples of areas critical for the understanding of battery functions where these methods can be used include the ion transport in the electrodes and the construction of models of the very complex Solid-Electrolyte Inter-phase (SEI) which is critical for the function of Li-ion batteries. As these are inherently multiscale problems the outputs from these simulations will be used to inform larger-scale models based on classical atomistic and continuum descriptions of materials. The pioneering applications of quantum methods during this PhD will be formulated into workflows that will provide robust generally applicable frameworks suitable for future simulations of batteries.
Dassault Systèmes will provide periods of placement in their research group in Cambridge where the PhD student will be able to get first-hand experience in industry standard multiscale simulation techniques applied to battery materials and in case studies from industry. The project will also involve close interaction with the Multiscale Modelling of Batteries consortium of the Faraday Institution, of which Southampton University is a founding partner.