SEARCH · Engineering Papers

Results for “NaAlCl4”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

3 records

All sources NASA NTRS DOE OSTI

DOE OSTI2020

A High-Performance Na-Al Battery Based on Reversible NaAlCl4 Catholyte

This work demonstrates a high-capacity and safe Na-Al battery pairing sodium metal anode and reversible NaAlCl4 catholyte for grid scale energy storage applications. The energy-rich sodium anode allows the full play of the aluminum cathode, resulting in a full-cell capacity of 308 mAh/g at a discharge voltage of 1.6 V. Benefiting from the use of ??-alumina solid electrolyte (BASE), molten sodium anode and reversible Al deposition/stripping from NaAlCl4 catholyte, the battery presents a stable Coulombic efficiency of 100% and energy efficiency of ~95%. At a rate of C/3 (6.77 mA/cm2), the cell maintains 282 mAh/g (447 Wh/kg) after 200 cycles with an excellent capacity retention of 97.6%. Moreover, we elucidate pathways to build sodium-anode-free cells from the discharged state under dry air, which further extends the feasibility of this battery for stationary storage applications. These findings are expected to provide a new platform for the development of practical Al batteries.

Zhan, Xiaowen↗

DOE OSTI2020

Materials Data on NaAlCl4 by Materials Project

NaAlCl4 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is three-dimensional. Na1+ is bonded in a 7-coordinate geometry to seven Cl1- atoms. There are a spread of Na–Cl bond distances ranging from 2.83–3.46 Å. Al3+ is bonded in a tetrahedral geometry to four Cl1- atoms. There are three shorter (2.16 Å) and one longer (2.17 Å) Al–Cl bond lengths. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one Al3+ atom. In the second Cl1- site, Cl1- is bonded in a bent 120 degrees geometry to one Na1+ and one Al3+ atom. In the third Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two equivalent Na1+ and one Al3+ atom. In the fourth Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two equivalent Na1+ and one Al3+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2021

In-situ anodic precipitation process for highly efficient separation of aluminum alloys

Electrorefining process has been widely used to separate and purify metals, but it is limited by deposition potential of the metal itself. Here we report in-situ anodic precipitation (IAP), a modified electrorefining process, to purify aluminium from contaminants that are more reactive. During IAP, the target metals that are more cathodic than aluminium are oxidized at the anode and forced to precipitate out in a low oxidation state. This strategy is fundamentally based on different solubilities of target metal chlorides in the NaAlCl4 molten salt rather than deposition potential of metals. The results suggest that IAP is able to efficiently and simply separate components of aluminum alloys with fast kinetics and high recovery yields, and it is also a valuable synthetic approach for metal chlorides in low oxidation states.

36 MATERIALS SCIENCE↗