Solid electrolyte interphases for high-energy aqueous aluminum electrochemical cells.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30515458.
- Also identified by DOI 10.1126/sciadv.aau8131 and PMC identifier 6269156.
- Licence recorded as CC BY-NC.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Electrochemical cells based on aluminum (Al) are of long-standing interest because Al is earth abundant, low cost, and chemically inert. The trivalent Al<sup>3+</sup> ions also offer among the highest volume-specific charge storage capacities (8040 mAh cm<sup>-3</sup>), approximately four times larger than achievable for Li metal anodes. Rapid and irreversible formation of a high-electrical bandgap passivating Al<sub>2</sub>O<sub>3</sub> oxide film on Al have, to date, frustrated all efforts to create aqueous Al-based electrochemical cells with high reversibility. Here, we investigate the interphases formed on metallic Al in contact with ionic liquid (IL)-eutectic electrolytes and find that artificial solid electrolyte interphases (ASEIs) formed spontaneously on the metal permanently transform its interfacial chemistry. The resultant IL-ASEIs are further shown to enable aqueous Al electrochemical cells with unprecedented reversibility. As an illustration of the potential benefits of these interphases, we create simple Al||MnO<sub>2</sub> aqueous cells and report that they provide high specific energy (approximately 500 Wh/kg, based on MnO<sub>2</sub> mass in the cathode) and intrinsic safety features required for applications.