Breakthrough in Aqueous Aluminium-Bromine Batteries Offers Sustainable Energy Storage Solution

A team of researchers at Technical University Dresden has made a significant discovery in the development of aqueous aluminium-bromine batteries, potentially paving the way for a more sustainable and large-scale energy storage solution. The research, published in Nature Communications, presents a hydrate-melt electrolyte design that enables the demonstration of aqueous Al-Br batteries with enhanced energy-power characteristics. This breakthrough addresses the critical bottleneck of realizing cathodes with high areal capacities.

Key Takeaways:

• The hydrate-melt electrolyte design utilizes cost-effective AlCl and organic halide salts, enabling aqueous Al-Br batteries with improved energy-power characteristics.
• The optimal electrolyte features suppressed water activity and loosely bound halogen anions, attributed to its unique electrolyte structure.
• The electrolyte allows for Zn-Al alloying/de-alloying with minimal polarization (around 100 mV at 5 mA cm) and a smooth alloy surface.
• The assembled Al-Br cell delivers an energy density (267 Wh L) comparable to commercial Li-ion batteries and a substantial power density (1069 W L) approaching electrochemical capacitors.
• The research team, led by Jingwei Du, creates a potentially game-changing energy storage solution for large-scale applications.
• The inclusion of cost-effective materials (AlCl and organic halide salts) reduces the overall cost of the battery.
• The reported areal capacity of 5 mAh cm is significantly higher than current aluminium-based aqueous batteries.
• The research concludes that the hydrate-melt electrolyte design offers a promising solution for the development of next-generation sustainable batteries.

Statistics:

• 98% of water molecules engage in robust ion solvation in the electrolyte.
• The Al-Br cell achieves an energy density of 267 Wh L, comparable to commercial Li-ion batteries.
• Power density reaches 1069 W L, approaching the level of electrochemical capacitors.
• The optimal electrolyte features suppressed water activity, which enhances the battery's performance.
• The assembled Al-Br cell displays a substantial power density, indicating potential for efficient energy storage and release.

Sources:

• Du, Jingwei, et al. "Hydrate-melt electrolyte design for aqueous aluminium-bromine batteries with enhanced energy-power merits." Nature Communications, vol. 16, no. 1, 2025, p 6329.
• Nature Communications, Heidelberger Platz 3, Berlin, 14197, Germany. (Nature Publishing Group - www.nature.com/; Nature Communications - www.nature.com/ncomms/)
• Technical University Dresden, Dresden, Germany.
• Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry, Technical University Dresden (TU Dresden), Dresden, Germany.