A composite cathode with a three-dimensional ion/electron-conducting structure for all-solid-state lithium–sulfur batteries

• Published in: Communications materials Vol. 5; no. 1; pp. 105 - 14
• Main Authors: Jiang, Peilu, Zhou, Huangkai, Song, Subin, Suzuki, Kota, Watanabe, Kenta, Yamaguchi, Yumi, Matsui, Naoki, Hori, Satoshi, Kanno, Ryoji, Hirayama, Masaaki
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 20.06.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 639/4077/4079/891; 639/638/161/891; Carbon fibers; Cathodes; Chemistry and Materials Science; Discharge; Electrochemical analysis; Electrode materials; Insulation; Liquid phases; Lithium; Lithium sulfur batteries; Materials Science; Robustness (mathematics); Solid electrolytes; Solid state; Sulfur; Three dimensional composites
• ISSN: 2662-4443; 2662-4443
• DOI: 10.1038/s43246-024-00537-w

All-solid-state lithium–sulfur batteries exhibit high energy densities, operate safely, and suppress polysulfide shuttling. However, their electrochemical performance is restricted by the insulating nature of sulfur and Li 2 S, and by severe cathode-related volumetric changes during cycling. Here, we prepare a Li 2 S-based cathode composite with high mixed-conductivity and stability, by infiltrating a Li 2 S–LiI active material solution into a mesoporous carbon replica with ~10-nm-sized pores, followed by mixing with a liquid-phase-synthesized Li 6 PS 5 Br solid electrolyte and vapour-grown carbon fibres. Benefiting from a mechanically reinforced, three-dimensional ion/electron-conducting structure, the cathode exhibits high discharge capacity (1009 mAh g −1 , 20 cycles, 298 K, 0.05 C) and high reversible capacity (650 mAh g −1 , 100 cycles, 298 K, 0.1 C). These findings underscore the feasibility of developing high-performance all-solid-state lithium-sulfur batteries by designing three-dimensional mixed-conducting mechanically robust cathodes. New cathode materials are needed for all-solid-state lithiumsulfur batteries. Here a mechanically robust Li 2 S-based composite cathode with a three-dimensional structure is prepared based on liquid-phase methods, achieving a high discharge capacity and reversible capacity.