Synchronously Consolidating Li, Se, S, and C for Robust Li-SeS Batteries

Mengmeng Qian; Feng Wu; Junfan Zhang; Yun Li; Chongteng Wu; Duanyun Cao; Jing Wang; Tinglu Song; Longlong Fan; Yifei Yuan; Jia-Qi Huang; Guoqiang Tan

doi:10.1021/acs.nanolett.4c01388

Synchronously Consolidating Li, Se, S, and C for Robust Li-SeS Batteries

Nano Lett. 2024 Oct 2;24(39):12027-12035. doi: 10.1021/acs.nanolett.4c01388. Epub 2024 Sep 23.

Authors

Mengmeng Qian^{1

2}, Feng Wu^{1

2}, Junfan Zhang^{1

2}, Yun Li³, Chongteng Wu^{1

2}, Duanyun Cao^{1

2}, Jing Wang^{1

2}, Tinglu Song¹, Longlong Fan⁴, Yifei Yuan³, Jia-Qi Huang^{1

5}, Guoqiang Tan^{1

2}

Affiliations

¹ School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China.
² Chongqing Innovation Center, Beijing Institute of Technology, Chongqing 401120, China.
³ College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China.
⁴ Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100049, China.
⁵ Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China.

PMID: 39311392
DOI: 10.1021/acs.nanolett.4c01388

Abstract

S-redox involving solvated polysulfides is accompanied by volumetric change and structural decay of the S-based cathodes. Here, we propose a synchronous construction strategy for consolidating Li, Se, S, and C elements within a composite cathode via a paradigm reaction of 8Li+2Se+CS₂ = 2Li₄SeS+C. The obtained composite features crystalline Li₄SeS encapsulated in a carbon nanocage (Li₄SeS@C), exhibiting ultrahigh electrical conductivity, ultralow activation barrier, and excellent structural integrity, accordingly enabling large specific capacity (615 mAh g^-1) and high capacity retention (87.3% after 350 cycles) at 10 A g^-1. TOF-SIMS demonstrates its superior volumetric efficiency to a similar derivative SeS@C (2Se+CS₂ = 2SeS+C), and DFT reveals its lower activation barrier than Li₂S@C and Li₂Se@C. This consolidation design significantly improves the electrochemical performance of S-based cathodes, and the paradigm reaction guarantees structural diversity and flexibility. Moreover, employing a synchronous construction mechanism to maximize the synergistic effect between element consolidation and carbon encapsulation opens up a new approach for developing robust S or chalcogenide cathodes.

Keywords: Li−SeS battery; carbon encapsulation; element substitution; sulfur cathode; synchronous consolidation.