Kameron Liao won the Best Presentation Award during The ECS – The Electrochemical Society 248th Meeting in Chicago.

Tuesday, 14 October 2025 
Abstract 

The development of next-generation energy storage technologies is crucial as the world shifts to renewable energy sources to address the climate crisis. While Li-ion batteries are mature and commercially successful, their energy density and costs are insufficient for future energy requirements. Lithium-sulfur (Li-S) batteries are a promising candidate due to their high theoretical energy density and the abundance of sulfur—an inexpensive and environmentally friendly substitute for the mined precious metals in conventional batteries. However, to achieve high energy densities, high sulfur loadings and minimized electrolyte-to-sulfur ratios are required. Such practical conditions often lead to low capacities and poor cycle life due to sluggish sulfur kinetics and accelerated electrode degradation.

This presentation focuses on how these challenges can be mitigated by optimizing the cathode microstructure. A scalable spray-drying process is employed to tailor the particle morphology of a sulfur/carbon composite, resulting in a cathode with uniform sulfur distribution and enhanced mechanical stability. Under stringent parameters, these electrodes deliver high capacities and improve the cycle life of a Li-S cell. The cell overpotential is further deconvoluted to identify key factors restricting faster rate performance. The typical kinetic barriers (activation polarization) are significantly alleviated at the potential-limiting Li2S nucleation step. Although diffusion limitations (concentration polarization) are also reduced, it emerges as the dominant contributor to the cell overpotential. Catalyst design alone can only mitigate the activation polarization, underscoring the need for continued optimization of the electrode microstructure to further reduce the concentration polarization. In all, this study highlights the critical role of electrode architecture design in advancing Li-S batteries toward commercial viability.