open access

https://hdl.handle.net/2115/72723

Preparation of sulfide solid electrolytes in the Li2S-P2S5 system by a liquid phase process

英語

2018-02

Royal Society of Chemistry

Inorganic Chemistry Frontiers

5(2)

501-508

Sulfide solid electrolytes in the Li2S-P2S5 system were synthesized by a liquid phase process under ultrasonic irradiation, and heat treatments at low temperatures. Crystal phase, structure, morphology and ionic conductivity of the sulfide electrolytes were examined after solvent removal at 180 degrees C and two different heat treatment temperatures, 220 degrees C and 250 degrees C. The study revealed that the ionic conductivities of the xLi(2)S center dot(100 - x)P2S5 sulfide electrolytes, in compositions with 70 <= x <= 75 mol%, are largely influenced by the local structure. The heat treatment at 220 degrees C was found to be an adequate temperature to promote crystallization of the high ionic conductive Li7P3S11 phase. Higher temperatures for heat treatment such as 250 degrees C lead to the formation of P2S64- (hypo-thiodiphosphate) units in the local structure of the sulfide electrolytes leading to a reduction of ionic conductivity. The formation and distribution of PS43- (orthothiophosphate), P2S74- (pyro-thiophosphate) and P2S64- units in the local structure were found to be key factors in achieving higher ionic conductivity (up to 10(-3)-10(-4) S cm(-1) at room temperature).

学術雑誌論文

Accepted Manuscript

2052-1553