Waterloo researchers make breakthrough in magnesium battery research with new electrolyte design
University of Waterloo researchers have made a key breakthrough in developing next-generation batteries that are made using magnesium instead of lithium.
When the idea to create batteries using magnesium was first shared in a seminal academic paper in 2000, that novel design didn’t provide enough voltage to compete with lithium-ion batteries, which are predominantly used in the marketplace. Magnesium is much more abundant and less costly than lithium, which would help further sustainable energy storage.
Now, the Waterloo team is one step closer to bringing magnesium batteries to reality, which could be more cost-friendly and sustainable than the lithium-ion versions currently available.
An example of a coin cell, which includes a magnesium-ion full battery with an organic cathode, magnesium metal anode, and the Waterloo-designed electrolyte. (University of Waterloo)
Linda Nazar, a professor in the Department of Chemistry and Canada Research Chair in Solid State Energy Materials, and Chang Li, a postdoctoral fellow in the Nazar Group, have designed an electrolyte that enables a highly-efficient magnesium anode. Li and Nazar collaborated with UC Berkeley and Sandia National Labs for this research.
Batteries have three main parts: a cathode (the positive side of the battery), an anode (the negative side of the battery), and a chemical solution known as an electrolyte that allows the flow of electrical charge between the cathode and anode.
Initial research on magnesium-based batteries generated one volt, less than what a standard AA battery operates at (1.5 volts). The electrolyte that Li and Nazar devised was found to operate at up to three volts with additional improvement expected to come with an even better cathode design.
“The electrolyte we developed allows us to deposit magnesium foils with extremely high efficiency and it is stable to a higher voltage than successfully tested before,” said Li. “All we need now is the right cathode to bring it all together.”
Placing an electrolyte-soaked glass fibre separator into a coin cell. (University of Waterloo)
While other researchers have had some success in this area, those studies used expensive materials that might be difficult to scale up for commercial use. Li and Nazar’s electrolyte design is inexpensive and could be scaled up quickly for the next-generation battery market. It is also non-corrosive and non-flammable, which were both problems with previous electrolyte iterations.
“This is another big step on the road towards commercializing a functional magnesium battery,” said Nazar. “We hope our work will open up a door for us, or someone else, to discover and develop the right positive electrode that will complete the magnesium battery puzzle.”
Their research, “A Dynamically Bare Metal Interface Enables Reversible Magnesium Electrodeposition at 50 mAh cm-2,” was published in Joule on Dec. 6. A copy of the research paper can be made available upon request.
