Flash Sintering of Li-Ion Conducting Lithium Lanthanum Titanate for Li-Air Batteries
Abstract
The U.S. Army needs high energy density, lightweight batteries, which can reduce Soldier load by up to 14 lb. One potential method to reduce the load is to replace disposable, alkaline batteries with lithium (Li)-air batteries, which weigh less due to high energy density and a porous air cathode. Li-air battery performance is limited by the electrolytic membrane, which must have an extremely high Li-ion conductivity. Li0.33La0.55TiO3 (LLTO) is a promising electrolytic membrane material due to its high lattice conductivity; however, the total conductivity of LLTO is lowered by its grain-boundary properties. Previous work shows careful structural modification and processing can improve the grain-boundary conductivity. For the current work, flash sintering densifies LLTO at temperatures well below the conventional sintering temperature. Excessive volatilization of Li could be avoided by reducing the time of exposure to high temperatures to improve grain-boundary conductivity. X-ray diffraction of the flashed specimens showed no significant phase change among specimens processed by other methods. Electrochemical-impedance-spectroscopy measurements were taken and results modelled to understand the nature of conductivity within the flashed samples. The effects of flash sintering on the microstructure and conductivity in comparison with conventionally sintered samples are discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 18, 2018
- Accession Number
- AD1056612
Entities
People
- Aubrey L. Fry
- Jeffrey Wolfenstine
- Michael Kornecki
- Raymond E. Brennan
- Selva V. Raju
- Victoria L. Blair
Organizations
- United States Army Research Laboratory