Lithium–sulfur batteries are widely seen as one of the most promising candidates for the next generation of energy storage, offering the potential for significantly higher energy density than today’s batteries while using abundant and inexpensive sulfur. However, several scientific and technological challenges still prevent their large-scale industrial deployment.
One key issue is the formation of soluble lithium polysulfides during battery operation, which can migrate inside the cell and lead to rapid capacity loss. Recent research suggests that a different reaction pathway, known as a “quasi-solid mechanism”, could limit this dissolution and significantly improve battery stability.
This PhD project aims to design and study lithium–sulfur pouch cells operating through this quasi-solid mechanism. The work will combine materials development, electrochemical testing, and advanced characterization techniques to better understand the processes governing battery performance and durability.
The project will focus on two complementary research directions:
1. Design of advanced sulfur cathodes
The first part of the work will involve developing optimized sulfur-based cathodes. This includes exploring different conductive host materials and tuning their structure and surface properties to better confine sulfur and reduce unwanted reactions.
2. Development of improved electrolytes
The second part of the project will focus on electrolyte formulations that reduce the solubility of polysulfides while maintaining good battery performance. Current solutions often rely on dense, fluorinated solvents that increase cost and environmental impact. This project will explore alternative solvent systems and investigate how salt composition and concentration influence cell behaviour.
To gain deeper insight into the quasi-solid reaction mechanism, the project may also involve operando or in-situ characterization techniques, such as Raman spectroscopy, X-ray diffraction, and high-resolution X-ray tomography.