The problem with lithium is that it’s an extremely limited resource, making up less than 0.002 percent of the Earth’s crust. Lithium’s scarcity makes it expensive, and the price will probably go even higher as the global demand for storage keeps rising.
Enter sodium. One of the two elements in ordinary salt, sodium is as cheap as (salted) chips and has a near-unlimited supply. And thanks to a team of talented researchers from the University of Wollongong (UOW), inexpensive and reliable sodium-ion batteries are only a few years away.
Supported by $2.7 million of ARENA funding, the $10.6 million battery project will develop modular, expandable sodium-ion batteries optimized for renewable energy applications.
The researchers are currently working out the sodium-ion chemistry that is best suited to large-scale applications. They have partnered with leading Chinese manufacturers to develop the sodium-ion cells and make them into 5 kilowatt-hours (kWh) packs that can be stacked together to create any size battery.
“Sodium-ion batteries are a field receiving intense research interest,” says Professor Shi Xue Dou, Project Leader and Director at UOW’s Institute for Superconducting and Electronic Materials (ISEM). “However, much of the work has been on the lab-scale development of materials.
“This is one of the first projects to focus on scaling up the production of sodium-ion materials and establishing the production capacity to manufacture sodium-ion battery cells at a commercial scale.
“We’ve had to develop a number of innovative approaches to address the issues that arise in scaling up this cutting-edge storage technology.”
The battery packs will get their first proper test at the Illawarra Flame House, an award-winning sustainable home on UOW’s Innovation Campus.
“We’ll be testing a single module in a residential-type application,” says Project Manager Jon Knott. “The Flame House can be hired out, so it’s often full of people.
“That means we can get usage patterns and start to see how the battery charges and discharges, and what sort of degradation we can expect to see in real-world batteries.”