A sulfur host based on silicon oxycarbide for advanced lithium-sulfur batteries

Author(s)

Amaral, Murilo M. ; Bin Mujib, Shakir ; Santos, Erick A. ; Ribeiro, Josimar ; Zanin, Hudson ; Singh, Gurpreet

• Document type: Journal article
• Source: JOURNAL OF ENERGY STORAGE; v. 72, p. 11-pg., 2023-11-25.

Abstract

Lithium-sulfur (Li-S) batteries are promising battery systems that provide high capacity and energy density using abundant materials, but they have a significant drawback known as the shuttle effect, which restricts their capacity, increases their internal resistance, and results in poor cyclability. Therefore, several efforts are being focused on overcoming this drawback, including the development of novel cathode materials based on carbonaceous hosts to adsorb lithium polysulfides (LiPS) and inhibit the shuttle effect, which is a challenging task. In this context, this study investigates the use of silicon oxycarbide (SiOC) as the sulfur host for Li-S systems with outstanding electrochemical performance. SiOC powder has been synthesized by pyrolysis process at 800 degrees C, using 1,3,5-trivinyl-1,1,3,5,5-pentamethyltrisiloxane (TPTS) as the precursor. The sulfur loading procedure consists of a melt-diffusion process conducted at 150 degrees C, which successfully diffused sulfur into the SiOC porous structure. Then, the S-SiOC composite material morphology and structure have been investigated by several techniques, which confirmed the efficacy of the sulfur loading process. The S-SiOC composite cathode provides a stable capacity, presenting a reversible charge capacity of 711 mAh gs  1 (& AP;50.3 % of its initial capacity) after 50 cycles at a current density of 83.75 mA gs  1 (0.05C, considering 1C = 1675 mA gs  1), indicating that this composite is a promising material for Li-S batteries. (AU)

• FAPESP's process: 21/09387-1 - In-situ FTIR and Raman spectroscopy of lithium-ion batteries and lithium-sulfur batteries
• Grantee: Murilo Machado Amaral
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 22/02222-0 - Development of prototype pouch cells of lithium-sulfur (Li-S) batteries in solid-liquid state with high stability and advanced scale of technological maturity
• Grantee: Érick Alves Santos
• Support Opportunities: Scholarships in Brazil - Doctorate