초록 |
Interest in batteries, which is the most important factor determining the performance of electric vehicles, is increasing. In line with these demands, All-solid-state batteries (ASSB) with higher energy density and higher stability have recently begun to attract attention. The key of ASSB is high quality solid-state electrolyte. NASICON-type lithium aluminum germanium phosphate (Li1.5Al0.5Ge1.5(PO4)3, LAGP) is regarded as one of the most promising solid electrolyte due to good chemical stability with Li. However, a number of recent studies have raised the awareness behind the issues of mixed conducting interphase (MCI) forming between LAGP and Li interface due to the degradation of ionic conductivity and fracture of LAGP with volume change during cycling. In this study, we made dense LAGP ceramics via modified pressureless sintering; in addition, partially reacted LAGP powders were prepared to analyze the sintering kinetics. Subsequently, we prepared MoS2 coated LAGP composite with various fabrication methods including MoS2 polishing, arranging exfoliated MoS2 nano-sheet, and applying vertically-aligned MoS2 by CVD growth. Therefore, Li ions are effectively intercalated into MoS2 layers to form a lithiophilic interface, which prevents the formation of MCI. It is our goal to establish an approach of designing a lithiophilic interface with 2D materials for high performing all-solid-state lithium metal batteries. |