Laser-induced transferred MnOx-CoOx-MoS₂@CC cathodes for lithium-sulfur battery

Abstract

Lithium-sulfur (Li-S) batteries have surfaced as a hopeful substitute for conventional lithium-ion batteries, presenting notably increased energy densities. The significance of Li-S batteries rests in their capacity to transform energy storage technologies, paving the way for extended and enhanced power reservoirs across diverse applications, from handheld gadgets to electric transportation. Harnessing the considerable theoretical energy density of sulfur, Lithium-Sulfur batteries possess the capability to address pivotal challenges in the transition towards sustainable energy infrastructures and the advancement of electrified transportation systems. Although holding great promise, the broad acceptance of Li-S batteries has been hindered by a range of obstacles, from intricate manufacturing processes to the fine-tuning of their operational features. The synthesis of the cathode material for Li-S batteries typically involves multiple steps. This encompasses synthesizing sulfur-based materials involving precise chemical reactions and tailored heat treatments, alongside the meticulous integration of conductive additives to enhance electronic conductivity. Through precise synthesis techniques that enhance the cathode design, scientists strive to fine-tune the electrochemical capabilities of Li-S batteries. This approach targets challenges like polysulfide dissolution, aiming to usher in cutting-edge energy storage innovations that offer extended lifespan and heightened environmental friendliness. In this study, I presented a novel approach that simplifies the production process of Li-S batteries, aiming to overcome existing complicated fabrication and accelerate the realization of their full potential in the energy storage landscape. The laser printing technique was used to synthesize the host and active materials to achieve single-step cathode fabrication. The laser printing technique was employed to synthesize both the host and active materials in a single-step process for the MnO_x-CoO_x-MoS₂-S@CC battery cathode. This innovative approach enabled the battery to showcase an impressive initial discharge capacity of 1195 mAh g^-1 over 100 cycles at a 0.2 C rate, indicating high charge storage capability and good cycling stability at a relatively slow discharge rate. Furthermore, the cathode material exhibited impressive resilience, retaining an initial discharge capacity of 733.5 mAh g^-1 across 1000 cycles at an accelerated 1 C rate. This underscores the batteries' outstanding long-term efficacy and durability in challenging operational environments.

Date of Award	2024
Original language	English
Awarding Institution	The Hong Kong University of Science and Technology
Supervisor	Mitch Li (Supervisor)