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  • LiAlO2/LiAl5O8 thin films derived from flame synthesized nanopowders as a potential electro-lyte and coating materials for all solid-state batteries (ASSBs)
Title: LiAlO2/LiAl5O8 thin films derived from flame synthesized nanopowders as a potential electro-lyte and coating materials for all solid-state batteries (ASSBs)
Recently, γ-LiAlO2 has attracted considerable attention as a coating in Li-ion battery electrodes. However, its potential as a Li+ ceramic electrolyte is limited due to its poor ionic conductivity (<10−10 S cm−1). Here, we demonstrate an effective method of processing LiAlO2 membranes (<50 μm) using nanopowders (NPs) produced via liquid-feed flame spray pyrolysis(LF-FSP). Membranes consisting of selected mixtures of lithium aluminate polymorphs and Li contents were processed byconventional tape casting of NPs followed by thermocompressionof the green films (100 °C/10 kpsi/10 min). The sintered greenfilms (1100 °C/2 h/air) present a mixture of LiAlO2 (∼72 wt %)and LiAl5O8 (∼27 wt %) phases, offering ionic conductivities (>10−6 S cm−1) at ambient with an activation energy of 0.5 eV. This greatly increases their potential utility as ceramic electrolytes for all-solid-state batteries, which could simplify battery designs, significantly reduce costs, and increase their safety. Furthermore, a solid-state Li/Li3.1AlO2/Li symmetric cell was assembled and galvanostatically cycled at 0.375 mA cm−2 current density, exhibiting a transference number ≈ 1.  more » « less
Award ID(s):
1926199
NSF-PAR ID:
10230948
Author(s) / Creator(s):
Date Published:
Journal Name:
ACS applied materials interfaces
Volume:
12
ISSN:
1944-8252
Page Range / eLocation ID:
46119–46131
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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