Ionic conductivity in solid electrolytes based on lithium aluminosilicate glass and glass-ceramic. [LiAlSiO/sub 4/;. beta. -eucryptite glass-ceramic;. beta. -spodumene]

Journal Article · Sat May 01 00:00:00 EDT 1976 · J. Electrochem. Soc.; (United States)

DOI:https://doi.org/10.1149/1.2132909· OSTI ID:7363494

Johnson, Jr, R T; Biefeld, R M; Knotek, M L; Morosin, B

Ionic conductivity measurements on LiAlSiO/sub 4/ glass and glass-ceramic showed these materials to be good lithium ion conducting solid electrolytes at high temperatures. This composition crystallizes in the ..beta..-eucryptite structure which is attractive for solid electrolyte applications because of its low thermal expansion. The glasses were prepared by quenching from the melt and were annealed to remove strain. The glass-ceramic (..beta..-eucryptite) samples were crystallized (aided by TiO/sub 2/ and ZrO/sub 2/ nucleating agents) by using a heat treatment determined through differential thermal analysis. The conductivity (sigma) was measured (to 650/sup 0/C) with a variety of techniques, including 2-terminal a.c., 3-terminal guarded a.c., 4-terminal a.c., 2-terminal d.c., and a pulsed method. Vapor-deposited Cr contacts were used. Different sample geometries, contact geometries, and measurement circuitries were employed. All results are in excellent agreement, and the a-c techniques appear to be the most versatile and accurate of the methods examined. In these materials the conductivity is thermally activated (sigma = sigma/sub 0/e/sup -E/kT/) with typical values of sigma/sub 0/ = 1.9 x 10/sup 2/ (ohm-cm)/sup -1/ and E approximately 0.68 eV for the glasses, and sigma/sub 0/ = 2.1 x 10/sup 4/ (ohm-cm)/sup -1/ and E approximately 1.05 eV for the glass-ceramics. The TiO/sub 2/ and ZrO/sub 2/ nucleating agents (concentrations up to 2.8 mole percent) did not appear to influence the ionic conductivity. Data were also taken on a (..beta..-eucryptite) glass-ceramic with a composition near the ..beta..-eucryptite/..beta..-spodumene phase boundary. The ionic conductivity of this material is lower than that of the LiAlSiO/sub 4/ materials. Data are also provided on ..beta..-spodumene material. 8 figures, 35 references. (auth)

• Research Organization: Sandia Labs., Albuquerque, NM
• OSTI ID: 7363494
• Journal Information: J. Electrochem. Soc.; (United States), Vol. 123:5
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM SILICATES
IONIC CONDUCTIVITY
ELECTROLYTES
LITHIUM SILICATES
CERAMICS
CRYSTALLIZATION
GLASS
MINERALS
ALKALI METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
LITHIUM COMPOUNDS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
SILICATES
SILICON COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties