On the electrochemical properties of lithium-sulfur batteries

Author(s)

Santos, Erick A. ; Fernandes, Rodolfo C. ; Vicentini, Rafael ; Aguiar, Joao Pedro ; Da Silva, Leonardo M. ; Zanin, Hudson

• Document type: Journal article
• Source: JOURNAL OF ENERGY STORAGE; v. 71, p. 14-pg., 2023-11-01.

Abstract

We report in this work the electrochemical analysis of lithium-sulfur batteries (LSB) composed of sulfur and activated carbon (AC) as the positive electrode and lithium metallic as the negative electrode. Cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy (EIS) techniques were employed for the in-situ characterization of the coin cell battery device. Electrochemical studies were performed at different state-of-charge (SoC) in 5 %-steps, covering the 0 to 100 % range. Our major findings include a high specific capacity of 1044 mAh gsulfur- 1 , which decreased to 200 mAh g-1 after 150 cycles. At the same time, the coulombic efficiency increased during the discharge from 78 % to 99 % due to a progressive activation of the narrow pores present in AC structures. Galvanostatic EIS findings as a function of SoC helped us in predicting the SoC and state-of-health (SoH). A 1500-h self-discharge result was presented and analyzed, indicating the presence of a small leakage current of ca. 600 nA. All electrochemical findings were corroborated by a comprehensive exsitu materials characterization using Raman, scanning electron microscopy, X-ray photoelectron spectroscopy, and energy-dispersive X-ray spectrometry techniques. The electrochemical (in-situ) and ex-situ characterization of electrodes and coin cell devices allowed us to provide a critical discussion regarding the overall characteristic exhibited by LSBs. (AU)

• FAPESP's process: 18/02713-8 - Molecular dynamics of confined fluids: equilibrium and transport properties
• Grantee: Luís Fernando Mercier Franco
• Support Opportunities: Research Grants - Young Investigators Grants
• 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
• FAPESP's process: 20/04281-8 - Proposal for syntheses, characterization and application of electrodes for Li-S battery like capacitor
• Grantee: Érick Alves Santos
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 14/02163-7 - Development of supercapacitors devices from graphene, carbon nanotubes and diamonds
• Grantee: Hudson Giovani Zanin
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 16/25082-8 - Development of prototype of energy storer and supplier
• Grantee: Lenon Henrique da Costa
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 18/20756-6 - Pseudocapacitors from metal oxides and activated carbon composites
• Grantee: Willian Gonçalves Nunes
• Support Opportunities: Scholarships in Brazil - Doctorate