Stabilizing electrode/electrolyte interface in Li-S batteries using liquid/solid Li2S-P2S5 hybrid electrolyte

Abstract

Lithium-sulfur (Li-S) batteries using hybrid electrolytes, which are composed of solid-electrolyte separator and liquid-electrolyte wetting agent, can effectively eliminate the polysulfide shuttling issue. The cycling performance of these hybrid batteries is mainly limited by the interfacial stability between the solid and liquid electrolytes. This work detailly discusses the influence of the composition on the stability of a highly ionic conductive sulfide solid electrolyte, lithium thiophosphate xLi 2 S•(100-x)P 2 S 5 (70≤x≤75, SSEs), in hybrid Li-S batteries. It reveals that the solid electrolyte with low Li 2 S content favors the formation of a SEI layer containing Li 3 PS 4 and therefore improves the interfacial stability with Li anode, while the one with high Li 2 S content behaves more stable with the cathode. Using 75Li 2 S•25P 2 S 5 as the separator, a hybrid battery runs more than 400 cycles with a low capacity fading rate of 0.14%/cycle. This is benefited from the elimination of polysulfide shutting and especially the excellent compatibility of the sulfide solid electrolyte with both anode and cathode.Hybrid Li-S battery (x=75) yields 400 cycles due to its excellent compatibility with the electrodes.

MOFs Containing Solid‐State Electrolytes for Batteries

“…[ 48 ] Therefore, some attempts have been made to introduce MOFs into GPEs to make use of the high ionic conductivity of MOFs materials and the stability of the interface with electrodes. [ 49 ]…”

Stabilizing Interface between Li2S–P2S5 Glass-Ceramic Electrolyte and Ether Electrolyte by Tuning Solvation Reaction

“…They are widely used for Li−S batteries. 28−30 In previous work, 31,32 we observed that 75Li 2 S−25P 2 S 5 glass-ceramics can form stable SLEIs with a conventional ether-based electrolyte, 1 M LiN(CF 3 SO 2 ) 2 (LiTFSI) in 1,3-dioxolane/1,2-dimethoxyethane (DOL/DME, 50−50 vol %), owing to the formation of a dense DME-solvated Li 3 PS 4 layer at the interface. Consequently, hybrid Li−S batteries using Li 2 S−P 2 S 5 glassceramics as the separator show better cycling stability than those using certain oxide electrolyte separators.…”

“…Ether solvents exhibit strong ability to dissolve polysulfide and good compatibility with lithium anodes. They are widely used for Li–S batteries. − In previous work, , we observed that 75Li 2 S–25P 2 S 5 glass-ceramics can form stable SLEIs with a conventional ether-based electrolyte, 1 M LiN­(CF 3 SO 2 ) 2 (LiTFSI) in 1,3-dioxolane/1,2-dimethoxyethane (DOL/DME, 50–50 vol %), owing to the formation of a dense DME-solvated Li 3 PS 4 layer at the interface. Consequently, hybrid Li–S batteries using Li 2 S–P 2 S 5 glass-ceramics as the separator show better cycling stability than those using certain oxide electrolyte separators. , These results encourage us to systematically explore the properties of the SLEIs between Li 2 S–P 2 S 5 glass-ceramic SEs and ether-based electrolytes.…”

Organic–Inorganic Hybrid SEI Induced by a New Lithium Salt for High-Performance Metallic Lithium Anodes

“…This process will lead to a series of disadvantages, including low coulombic efficiency (CE), fast capacity fading, and severe self-discharging. 6 As for the anode, the rapid growth of lithium dendrites is also a serious problem. Dendrites provide preferential deposition sites for lithium, resulting in excessive consumption of electrolytes.…”

“…Over the entire procedure, the highly soluble LiPSs shuttle between the cathode and anode driven by the concentration gradient and electric field, resulting in the alleged “shuttle effect”. This process will lead to a series of disadvantages, including low coulombic efficiency (CE), fast capacity fading, and severe self-discharging . As for the anode, the rapid growth of lithium dendrites is also a serious problem.…”