Creating more sustainable batteries

5 Minute read

The Super Anode Project is led by Professor Amanda Ellis in the University’s Department of Chemical Engineering, and is funded by the Future Battery Industries Co-operative Research Centre, in partnership with CSIRO and the Queensland University of Technology. This project is working on how to make much more sustainable graphite anodes for lithium-ion batteries, without sacrificing the performance and stability that make these anodes so great.

Lithium-ion batteries are everywhere. We now have far more electronic devices than people, each with a battery. We use them in our electricity networks. And we are increasingly using them in our cars.

These batteries are, in principle, simple devices. They consist of an anode, an electrolyte that contains lithium, and a cathode. But there is an awful lot of science and innovation in each of these components, let alone how we put batteries together and use them.

Lithium-ion battery anodes are themselves a big business. Made from graphite, the performance of the anode helps determine the power and energy of a lithium-ion battery. The anode is particularly important because it’s where the lithium ions are ‘trapped’ when the battery is charged. So how many ions the anode can hold, and how fast they can be stored or released, determines many of the battery’s properties.

Graphite is cheap and abundant, and there is a wealth of knowledge of how we can process, functionalise and use it. While other materials such as tin and silicon can store more ions, none approach graphite’s useful lifetime.

However, graphite anodes also have a rather big problem - they are usually made using environmentally unsustainable practices. Graphite is naturally occurring and mined but is also made from coal tar and pet coke, the leftovers of crude oil refining. A large amount of energy is required to make this synthetic graphite. Its manufacture is also a significant source of air pollution.

Commercial anodes currently use a blend of natural and mostly synthetic graphite. With the booming lithium-ion battery industry, that can add up to a lot of emissions.

Natural graphite, in contrast, is a lot greener. There is therefore a big demand for natural graphite anodes that can match or even outperform blended or fully synthetic equivalents. Indeed, with our urgent need for much more renewable energy and the transition towards electric vehicles, it’s critical that lithium-ion batteries be more sustainable.

Professor Amanda Ellis leads a research group in the University’s Department of Chemical Engineering that is working on this challenge. Professor Ellis’ team is taking mined natural graphite from our industry partners and developing pathways for processing and device assembly, while benchmarking anode performance against leading commercial anode materials.

This Super Anode Project is funded by the Future Battery Industries Co-operative Research Centre and is in partnership with CSIRO and the Queensland University of Technology. An impressive team of postdoctoral research fellows and graduate students is exploring many different aspects of natural graphite anode development. Over the next four years, the capability to produce high performance natural graphite anodes in Australia will be developed.

If you would like to find out more about the Super Anode Project, Professor Ellis welcomes enquiries by email: amanda.ellis@unimelb.edu.au

This article was first published on 21 November 2021 by the Melbourne Energy Institute.