Lithium sulphur battery cathodes: New materials and advanced understanding

Li-S batteries offer high energy densities at low cost. Unfortunately fundamental challenges relating to their active materials limit their applicability. In particular, work must be done to combat irreversible capacity loss, electrode volume expansion and anode passivation due to lithium polysulphides (LiPSs). A combination of greater fundamental understanding of the properties of Li-S battery materials as they operate and new functional electrodes will enable industrial Li-S battery application. In this project we will develop high-throughput techniques to simultaneously detect LiPSs in solution and electrode mass/morphology/viscoelastic changes. We will also develop new functional hierarchical cathode materials to accommodate volume change promote efficient sulphur distribution. Objectives: 1) Develop instrumentation to combine generation-collection electrochemistry with electrochemical quartz crystal microbalance measurements, allowing simultaneous LiPS detection and material change analysis. 2) Create novel, highly efficient, high conductivity porous cathode hosts with LiPS trapping functionality and study their structure-operational function relationships in Li-S batteries. 3) Scale materials developed to pouch-cell level, enabling true industrial verification. Techniques to be learned include: Materials synthesis, electrochemical methods, x-ray computed tomography, small-angle x-ray scattering, electron microscopy, atomic force microscopy and spectroscopic techniques.