Silver boosts ultra-long cycle life for metal sulfide lithium-ion battery anodes: Taking AgSbS2 nanowires as an example

Metal sulfide, being a high-capacity anode material, is a promising anode material for rechargeable lithium-ion batteries (LIBs). However, most research efforts have focused on improving their low cycling performance due to multiple combined factors, including low conductivity, huge volume changes, multistep conversion/alloying reactions, and redox shuttling effect, during the cycling process. Here, we report that by using AgSbS2 nanowires as LIB anode materials, a record-breaking long cycle life metal sulfide anode has been achieved through the silver synergistic electrochemical performance effect. We found that while the AgSbS2 nanowire anode is cycled, Ag precipitated out to form a nanocrystal tightly connected with Sb and S and plays a key role in highly-reversible electrochemical performance. Ag can effectively enhance the electrode conductivity, increase ion diffusion rate, serve a diluent huge volume changes during conversion-alloying reactions, improve the absorbability and catalytic ability towards LiPSs to reduce shutting effect of sulfur, and enhanced Li+ adsorption. As a result, AgSbS2 nanowire anodes maintain 90% capacity retention over 5000 and 7000 cycles at the current densities of 500 mA g(-1) and 2000 mA g-(1), respectively, whereas the capacities of Sb2S3 nanowire and Sb2S3/C nanowire anodes drop rapidly within 10 cycles. The ultra-stable cycle life is superior to the state-of-the-art metal sulfide anodes. Finally, using AgSbS2 nanowires as the anode combined with the cathode LiNi5Co3Mn2, a full battery after 480 cycles was assembled to verify that its stability (high retention rate of 99.5%) can be used in the current commercial battery architecture. This work solves multiple problems related to shuttling effects and complex reactions of metal sulfide anodes, and provides important progress for the future development of metal sulfide anodes for LIBs. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

By using AgSbS2 nanowires as anode materials, a record-breaking long cycle life for metal sulfide anodes has been achieved. The presence of Ag enhances the electrochemical performance by improving conductivity, ion diffusion rate, and adsorption capability, while reducing the shuttling effect of sulfur. This research has significant implications for the future development of metal sulfide anodes.