Toward robust lithium-sulfur batteries advancing LiS deposition

• Published in: Chemical science (Cambridge) Vol. 15; no. 21; pp. 7949 - 7964
• Main Authors: Jiao, Xun, Tang, Xiaoxia, Li, Jinrui, Xiang, Yujiao, Li, Cunpu, Tong, Cheng, Shao, Minhua, Wei, Zidong
• Format: Journal Article
• Published: 29.05.2024
• ISSN: 2041-6520; 2041-6539
• DOI: 10.1039/d4sc02420f

Lithium-sulfur batteries (LSBs) with two typical platforms during discharge are prone to the formation of soluble lithium polysulfides (LiPS), leading to a decrease in the cycling life of the battery. Under practical working conditions, the transformation of S 8 into Li 2 S is cross-executed rather than a stepwise reaction, where the liquid LiPS to solid Li 2 S conversion can occur at a high state of charge (SOC) to maintain the current requirement. Therefore, advancing Li 2 S deposition can effectively reduce the accumulation of LiPSs and ultimately improve the reaction kinetics. Herein, a "butterfly material" GeS 2 -MoS 2 /rGO is used as a sulfur host. Rich catalytic heterointerfaces can be obtained via the abundant S-S bonds formed between GeS 2 and MoS 2 . MoS 2 (left wing) can enhance LiPS adsorption, while the lattice-matching nature of Fdd 2 GeS 2 (right wing) and Fm 3&cmb.macr; m Li 2 S can induce multiple nucleation and regulate the 3D growth of Li 2 S. Li 2 S deposition can be advanced to occur at 80% SOC, thereby effectively inhibiting the accumulation of soluble LiPSs. Attributed to the synergistic effect of catalytic and lattice-matching properties, robust coin and pouch LSBs can be achieved. The GeS 2 -MoS 2 /rGO heterostructure is designed as a sulfur host to facilitate the conversion of polysulfides and advance the deposition of Li 2 S synergistically by strengthening the hybrid current during cycling.