EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

All solid-state batteries (ASSBs) are anticipated to be the next generation lithium ion batteries with their wider operating temperature range, higher energy density, and increase in safety performance compared to conventional liquid electrolyte-based batteries [1,2]. These advantages make them potential candidates for electric vehicles, but many processing and performance challenges must be addressed. Among various solid Li+ ion conducting electrolytes, the inorganic fluoride-based materials such as Li3MF6 and garnet-type Li3Na3M2F12 (M = Al, Sc, In) have attracted greater interest because of their high electrochemical stability, excellent mechanical properties, good interfacial compatibility and easy fabrication [3,4].
In this work, we synthesized fluoride lithium metal garnets, Li3Na3M2F12 (M = Al, Sc, In) by high-energy ball milling and the samples were structurally characterized by powder Rietveld refinement, scanning electron microscopy. The temperature-dependent ionic conductivity and real and imaginary part of the impedance (vs. frequency) were performed on pelletized fluoride garnets by AC impedance spectroscopy. The Li+ ionic conductivities of Li3Na3Al2F12, Li3Na3Sc2F12 and Li3Na3In2F12 found to be 1.7x10-6, 8.2x10-6 and 2.4x10-6 S/cm at 300 oC, and are retained about 1.2x10-10, 2.6x10-9 and 1.8x10-10 S/cm at 100 oC, respectively. The activation energies (Ea) for these materials are in the range of 0.83 to 0.97 eV.

References:
[1] S. A. Pervez, M. A. Cambaz, V. Thangadurai, M. Fichtner, ACS Appl. Mater. Interfaces 11 (2019) 2202922050.
[2] Umeshbabu Ediga, B. Zheng and Yong Yang (2019). Electrochem. Energy Rev. 2 (2019) 199–230.
[3] M. Feinauer, H. Euchner, M. Fichtner, M. Anji Reddy, ACS Appl. Energy Mater. 2 (2019) 71967203.
[4] Y. Takeda, M. Sone, Y. Suwa, M. Inagaky, S. Naka, J. Solid State Chem. 20 (1977) 261265.