About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
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Materials and Chemistry for Molten Salt Systems
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Presentation Title |
Keep It Lewis-Basic: Stability of NaSICON Separators in AlCl3-NaI Catholytes for Molten Sodium Batteries |
Author(s) |
Adam Maraschky, Melissa L. Meyerson, Stephen J. Percival, Amanda S. Peretti, Erik D. Spoerke, Leo J. Small |
On-Site Speaker (Planned) |
Adam Maraschky |
Abstract Scope |
We examined sodium batteries with NaI-AlCl3-based molten salt catholytes of differing Lewis acidities. Batteries with AlCl3-rich (acidic) catholytes experienced a linear decline in energy efficiency during cycling, whereas NaI-rich (basic) catholytes maintained a steady > 95% energy efficiency for > 50 cycles. We developed a 3-electrode cell, which enabled identification of the NaSICON-catholyte interface as the source of increased battery impedance. XPS revealed a decrease in Na content in the NaSICON exposed to the acidic catholyte. Raman spectroscopy indicated that basic catholytes lack the dimer species found in acidic catholytes. The relative reactivity of chloroaluminate species with NaSICON’s constituent metal oxides was correlated based on thermodynamics. The mechanistic causes for NaSICON’s susceptibility to Lewis-acidic degradation will be discussed. Recent progress towards achieving high current densities through NaSICON in these molten salt systems will also be shared. |
Proceedings Inclusion? |
Planned: |
Keywords |
Energy Conversion and Storage, Ceramics, Characterization |