“Sweetening” to light weight Li-S Batteries

Batteries for Aviation: the new lithium-sulfur battery technology could store two to five times more energy. The Monash Energy Institute team (L-R): Mahdokht Shaibani, Mainak Majumder, Matthew Hill, Yingyi Huang. Credit: Monash Energy Institute

Sugar coating enables Lithium-Sulfur technology

“Simply by adding sugar, researchers from the Monash Energy Institute have created a longer-lasting, lighter, more sustainable rival to the lithium-ion batteries that are essential for aviation, electric vehicles and submarines.” states the key summation of the accomplishment on the Melbourne Monash University’s Monash Energy Institute (MEI) webpage. (A)

A MEI research group at has discovered what promises to be a path to light weight batteries with a heretofore unattainable power to weight ratio, lower costs, technically sufficient load cycles and a better sustainable material composition.

Lithium – Sulfur battery technology has been known for a while. It promises a factor five higher energy to weight ratio as compared to Lithium Ion battery technology. To date its main deterring factor was the inherent electrodes instability of the Li-S battery cells. 50 to 80 loading cycles seemed to be the limit for the technology. Now the Australian research team has announced their success in finding a solution to this problem.

Their laboratory pouch cell prototype batteries deliver at least 1000 loading cycles. At this providing an initial capacity at around 1200 mAh g-1. Already these batteries load cycle degrading is at to 1106 mAh g-1 at 500 cycles and at roughly 700 mAh g-1 at 1000 cycles. Details are published in the Nature Communications paper dated 10 September 2021 by Yingyi Huang, Mahdokht Shaibani, et al (B). Very encouraging results for alab prototype stage. The achieved power storage capacity far exceeds those of lithium-ion batteries.

The new batteries have additional sustainability enhancing characteristics. As stated by first author PhD student Yingyi Huang:

“…each charge lasts longer, extending the battery’s life, … and manufacturing the batteries doesn’t require exotic, toxic, and expensive materials”. (A)

However, further research is still needed to achieve the stage to full transfer into an industrial technology implementation. Dr Mahdokht Shaibani, second author and Monash researcher, says:

“While many of the challenges on the cathode side of the battery has been solved by our team, there is still need for further innovation into the protection of the lithium metal anode to enable large-scale uptake of this promising technology – innovations that may be right around the corner.” (A)

This development is the achievement of the Lithium-sulfur Battery Research Program at Monash University. It has been supported by the Commonwealth Government through the Australian Research Council and the Department of Industry, Innovation and Science. In addition, the work has also been supported by Cleanfuture Energy, Australia, an Australian subsidiary of the Enserv Group of Thailand. (A)

As MEI reports, Enserv Australia hopes to develop and manufacture the batteries in Australia. Australia is currently the world largest producer of lithium.

At this we might have to wait for the market availability of these Li-S batteries for another 5 to 10 years. Considering the industrial product development cycle most likely the longer when it comes to aviation applications with their necessary stringent safety and quality control requirements.

However, thanks to the creativity of the Australian researchers we, the aviation industry, finally seem to have a viable way to a future of sustainable electrically powered flight with battery technology. Very promissing initial expectations and predictions are given by the current research team on performance, production price and materials. If true, this could prove to be one of the most momentous development and material sciences discovery for the aviation industry this century.

While the Li-Ion technology is still improving both in price and load cycle achievements, it still has two major drawbacks regarding aviation:

  • its chemical volatility if exposed to air or water and
  • its low power to weight ratio.

Aviation therefore might provide the most interesting initial applications for the new sugar coated Li-S batteries.

It remains to be seen in further studies and developments how the comparative sustainable applications will fare.

Between Power-to-Liquid, Fuel Cell, and now Li-S batteries technologies the field of suitable propulsion and power technologies for aviation starts to reach a configuration to be confident about viable technical paths and solutions for a future sustainable aviation industry.

Author: Dr. Axel Laistner (IASA Journal)

Key Sources:

(A)         Monash Energy Institute, Media Releases, Sugar coating opens a path to low cost lithium sulfur batteries, 10 September 2021

(B)         Huang, Y., Shaibani, M., Gamot, T.D. et al. A saccharide-based binder for efficient polysulfide regulations in Li-S batteries. Nat Commun 12, 5375 (2021). https://doi.org/10.1038/s41467-021-25612-5