Ceramic–Salt Composite Electrolytes from Cold Sintering. (1st April 2019)

• Record Type: Journal Article
• Authors: Lee, Wonho; Lyon, Christopher K.; Seo, Joo‐Hwan; Lopez‐Hallman, Raymond; Leng, Yongjun; Wang, Chao‐Yang; Hickner, Michael A.; Randall, Clive A.; Gomez, Enrique D.
• Is Part Of: Advanced functional materials. Volume 29:Number 20(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-04-01
• Subjects: all solid state Li metal batteries -- ceramic electrolytes -- composite electrolytes -- ionic conductivity -- low temperature sintering; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201807872
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: The development of solid electrolytes with the combination of high ionic conductivity, electrochemical stability, and resistance to Li dendrites continues to be a challenge. A promising approach is to create inorganic–organic composites, where multiple components provide the needed properties, but the high sintering temperature of materials such as ceramics precludes close integration or co‐sintering. Here, new ceramic–salt composite electrolytes that are cold sintered at 130 °C are demonstrated. As a model system, composites of Li1.5 Al0.5 Ge1.5 (PO4 )3 (LAGP) or Li1+ x + y Al x Ti2− x Si y P3− y O12 (LATP) with bis(trifluoromethanesulfonyl)imide (LiTFSI) salts are cold sintered. The resulting LAGP–LiTFSI and LATP–LiTFSI composites exhibit high relative densities of about 90% and ionic conductivities in excess of 10 −4 S cm −1 at 20 °C, which are comparable with the values obtained from LAGP and LATP sintered above 800 °C. It is also demonstrated that cold sintered LAGP–LiTFSI is electrochemically stable in Li symmetric cells over 1800 h at 0.2 mAh cm −2 . Cold sintering provides a new approach for bridging the gap in processing temperatures of different materials, thereby enabling high‐performance composites for electrochemical systems. Abstract : Ceramic–salt composite solid electrolytes are fabricated through cold sintering at 130 °C. Cold sintering enables integration of bis(trifluoromethanesulfonyl)imide (LiTFSI) with ceramics to achieve ionic conductivities near 10 −4 S cm −1 and relative densities of ≈90%. Stable cycling over 1800 h in Li metal symmetric cells is also demonstrated.