Tailoring the Spatial Distribution and Content of Inorganic Nitrides in Solid-Electrolyte Interphases for the Stable Li Anode in Li-S Batteries

Among the alternatives to lithium-ion batteries, lithium-sulfur (Li-S) batteries are considered as an attractive option because of their high theoretical energy density of 2570 Wh kg(-1). However, the application of the Li-S battery has been plagued by the rapid failure of the Li anode due to the Li dendrite growth and severe parasitic reactions between Li and lithium polysulfides. The physicochemical properties of the solid-electrolyte interphase have a profound impact on the performance of the Li anode. Herein, a lithium polyacrylic acid/lithium nitrate (LPL)-protective layer is developed to inhibit the dendrite Li growth and parasitic reactions by tailoring the spatial distribution and content of LiNxOy and Li3N at the SEI. The modified SEI is thoroughly investigated for compositions, ion transport properties, and Li plating/stripping kinetics. Consequently, the Li-S cell with a high S loading cathode (5.0 mg cm(-2)), LPL layer-protected thin Li anode (50 mu m), and 40 mu L electrolyte shows a long life span of 120 cycles. This work evokes the avenue for regulating the spatial distribution of inorganic nitride at the SEI to suppress the formation of Li dendrites and parasitic reactions in Li-S batteries and perhaps guiding the design of analogous battery systems.

Automated summary

A lithium polyacrylic acid/lithium nitrate (LPL) protective layer has been developed to inhibit dendrite Li growth and parasitic reactions in Li-S batteries by tailoring the spatial distribution and content of LiNxOy and Li3N at the solid-electrolyte interface (SEI). Through thorough investigation, the modified SEI layer has shown improved compositions, ion transport properties, and Li plating/stripping kinetics.