New hybrid electrolyte enables fast charging of Li batteries without catching fire

A new hybrid electrolyte, developed by an international research team shows excellent performance when used in lithium batteries and will not catch fire at high temperatures. 

The research, by Deakin PhD student Urbi Pal, storEnergy researchers from Monash and Deakin Universities, and Professor Shirley Meng’s group at the University of California San Diego (UCSD), worked on the novel ionic liquid based electrolyte for Li-metal batteries. 

The conventional battery electrolyte utilises the lithium metal in these batteries very poorly, where often the accumulation of these unutilised or ‘dead’ Li leads to degradation of battery performance and short circuit.

Urbi’s studies have shown that the ionic liquid based hybrid electrolyte does not allow accumulation of this dead lithium, thus allowing stable cycling of the lithium battery for hundreds of cycles without risk of short circuiting and catching fire.

After developing the new electrolyte, Urbi had the chance to visit the world leading group at UCSD, with its specialised advanced characterisation facilities. These tests confirmed the electrolyte’s outstanding performance under a range of charge conditions.

Using cryogenic electron microscopy (a very rare instrument), the researchers found that the newly designed hybrid ionic liquid electrolyte was able to plate very dense lithium and forms less dead lithium, which is an advantage over existing state-of-the-art electrolytes. 

Urbi says this research will help towards making better, high performing lithium batteries with non-flammable components for use, e.g. in electric vehicles and large-scale energy storage.

After being awarded her PhD early this year, Urbi is now working as an associate research fellow at Deakin with storEnergy industry partner Calix Ltd, testing battery materials and developing new electrolytes.

Interphase control for high performance lithium metal batteries using ether aided ionic liquid electrolyte. Urbi Pal, Dmitrii Rakov, Baharak Sayahpour, Fangfang Chen, Binayak Roy, D.R. MacFarlane, M. Armand, P.C. Howlett, Ying Shirley Meng and Maria Forsyth. Energy & Environmental Science 2022