Understanding electrode processes in Li-Sulfur Batteries

Batteries that extend performance beyond the fundamental limits of Lithium-ion (Li-ion) technology are essential for the transition away from fossil fuels. Amongst the most mature of these 'beyond Li-ion' technologies are lithium sulfur (Li-S) batteries. Li-S cells replace the metal rich cathode of Li-ion cells with comparatively cheap and abundant elemental sulfur, a material which also offers a five-fold improvement in capacity for the same weight compared with materials widely used in Li-ion cells. By using sulfur, lightweight cells can be produced using more cost effective materials, while also reducing the environmental and social concerns surrounding the production of nickel and cobalt.

In spite of their intrinsic advantages, Li-S batteries suffer from relatively poor lifetime and volumetric energy density compared with incumbent Li-ion technologies: this is a key challenge which is being addressed in the LiSTAR programme, with which this studentship is aligned. To counter this, an improved understanding of the fundamental mechanisms of Li-S operation is required, this will be achived through the application of advanced electrochemical and materials characterisation tools to understand the polysulfide shuttle effect, the active mass utilisation and electrode inventory loss. Understanding gained from these experiments will be used to inform rational design of Li-S electrodes with enhanced performance and energy density.