Low-Temperature Molten Salt Electrolytes for Membrane-Free Sodium Metal Batteries
Name
Sadoway_Low-temperature molten.pdf
Size
1.37 MB
Format
Adobe PDF
Checksum (MD5)
8179a01d499f4ea9a4b28d4a6cced3f7
Author(s)
Ouchi, Takanari
Lambotte, Guillaume
Burke, Paul J.
Sadoway, Donald Robert
Spatocco, Brian Leonard
Date Issued
October 2015
Journal
Journal of The Electrochemical Society
Publisher
Electrochemical Society
Citation
Spatocco, Brian L., Takanari Ouchi, Guillaume Lambotte, Paul J. Burke, and Donald R. Sadoway. “Low-Temperature Molten Salt Electrolytes for Membrane-Free Sodium Metal Batteries.” J. Electrochem. Soc. 162, no. 14 (2015): A2729–A2736.
Version
Final published version
Abstract
The liquid metal battery (LMB) is attractive due to its simple construction, its circumvention of solid-state failure mechanisms and resultantly long lifetimes, and its particularly low levelized cost of energy. Here, we provide a study of a unique binary electrolyte, NaOH-NaI, in order to pursue a low-cost and low-temperature sodium-based liquid metal battery (LMB) for grid-scale electricity storage. Thermodynamic studies have confirmed a low eutectic melting temperature (220°C) as well as provided data to complete the phase diagram of this system. X-ray diffraction has further supported the existence of a recently discovered compound, Na[subscript 7](OH)[subscript 5]I[subscript 2], as well as offered initial evidence toward a NaI-rich compound displaying Pm-3m symmetry. These phase equilibrium data have then been used to optimize parameters from a two-sublattice thermodynamic solution model to provide a starting point for study of higher order systems. Further, a detailed electrochemical study has identified the voltage window and related oxidation/reduction reactions and found greatly improved stability of the pure sodium electrode against the electrolyte. Finally, an Na|NaOH-NaI|Pb-Bi proof-of-concept cell was assembled. This cell achieved over 100 cycles and displayed leakage currents below 0.40 mA/cm[superscript 2]. These results highlight an exciting class of low-melting molten salt electrolytes that may enable low cost grid-scale storage.
MIT Department
Massachusetts Institute of Technology. Materials Processing Center
Massachusetts Institute of Technology. Department of Materials Science and Engineering
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1149/2.0441514jes
