Single-atom tailoring of Li2S to Form Li2S2 for building better lithium-sulfur batteries

Chenyang Zha, Shuo Wang, Chang Liu, Yuwei Zhao, Bingchen He, Chongguang Lyu, Junfeng Li, Shunping Ji, Shi Chen, Kwan San Hui, Kwun Nam Hui

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)

Abstract

The Li2S-based cathodes to couple with Li-free anodes are regarded as a commercially available approach to overcome the safety risk of lithium metal anodes. However, the passivated Li2S instinct leads to a high activation potential in the initial charging process, and the notorious shuttle effect of polysulfide is inevitable upon cell cycling. Here we create a single atom tailoring strategy by comproportionation reactions (Li2S + 1/8S8 = Li2S2) to form the Li2S2 materials without any complex manufacturing process or additives, where the Li2S2 cell enables a lower potential barrier and allows for the 3.0 V activation voltage without any other material modification. Meanwhile, the polar conducting material TaB2 is introduced to restrain the migration of polysulfides, and provide fast redox reaction kinetics. With those ingenious tailoring of cell designs, the Li2S2-TaB2 cell (Li2S2: 88 wt%) exhibits high areal capacity (4.6 mAh/cm2 at 6.0 mg/cm2 Li2S2 loading), excellent cycling stability (500 cycles at 1.6 mA/cm2).

Original languageEnglish
Pages (from-to)79-86
Number of pages8
JournalEnergy Storage Materials
Volume47
Early online date3 Feb 2022
DOIs
Publication statusPublished - May 2022

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