Li metal stability enhancement of Sn-doped Li2S-P2S5 glass-ceramics electrolyte. (10th September 2021)

• Record Type: Journal Article
• Authors: Park, Chanhwi; Lee, Sangsoo; Kim, Minhee; Min, Sanghyuk; Kim, Gideok; Park, Sangho; Shin, Dongwook
• Is Part Of: Electrochimica acta. Volume 390(2021)
• Publication Date: 2021-09-10
• Subjects: All-solid-state battery -- Sulfide solid electrolyte -- Glass-ceramics electrolyte -- Lithium metal anode -- Electrochemical stability -- Chemical stability; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2021.138808
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: The 80Li2 S-15P2 S5 -10SnS2 electrolyte enhanced chemical stability against Li metal. Without any other means to protect lithium dendrite growth, all-solid-state Li metal battery employing Sn-substituted electrolyte was successfully operated for extended period under 0.1C rate. Both the electrochemical stability and the mechanical properties of the sulfide electrolyte are indispensable for Li metal batteries. Abstract: All-solid-state lithium ion batteries (ASSLIBs) are very promising next-generation lithium ion batteries with high energy density and safety. Among the solid electrolytes that can be applied to ASSLIBs, sulfide glass-ceramics electrolytes are attracting attention because of their high ionic conductivity and good mechanical deformability. However, the lack of the chemical and electrochemical stability of the sulfide electrolytes under prolonged cycle operation has become a barrier limiting their practical use and commercialization. We investigated the effects of Sn substitution on the electrochemical and chemical stability enhancement of Li2 S-P2 S5 glass-ceramics electrolytes. Also, we analyzed the cause of the degradation by side reactions and lithium dendrite growth. For 80Li2 S-15P2 S5 -10SnS2 glass-ceramics electrolyte, only the redox current of the lithium deposition/dissolution was observed in cyclic voltammetry test with lithium metal. And the result of X-ray photoelectron spectroscopy analysis demonstrated a reduction in the amount of Li2 S and decomposition product from the sulfide solid electrolytes. ASSLIBs using 80Li2 S-15P2 S5 -10SnS2 as solid electrolytes with Li metal or Li-In anodes showed improved cycling performance compared to batteries employing 80Li2 S-20P2 S5 glass-ceramics. These results showed that Sn substitution is effective to improve the chemical and electrochemical stability of Li2 S-P2 S5 glass-ceramics electrolyte to lithium metal.