How Magnesium Makes For Safer Batteries

Scientists in Japan have found that adding a magnesium salt to lithium batteries makes them safer to use.

AsianScientist (Mar. 5, 2018) – A team of researchers from Shinshu University in Japan have found a new way to curb some of the potential dangers posed by lithium ion batteries. Their findings are published in Physical Chemistry Chemical Physics.

Lithium ion batteries are being adapted to power a multitude of devices, from smartphones to electric cars. However, lithium is inherently unsuitable for use in rechargeable batteries. The repeated lithium deposition/dissolution during charge/discharge can cause serious accidents due to the deposition of lithium dendrites, tiny protrusions that penetrate the separator and induce internal short-circuiting.

To overcome this problem, a research group led by Professor Susumu Arai at Shinshu University, introduced a type of magnesium salt—magnesium bis(trifluoromethanesulfonyl)amide—that is capable of combining with lithium to stop continued dendritic branching in the lithium metal.

“A number of approaches have been developed to prevent the growth of lithium dendrites… which are complicated and have some problems,” said Assistant Professor Masahrio Shimizu of Shinshu University, who is the first author of the paper. “In contrast, our strategy of adding magnesium salt is extremely simple.”

While magnesium bis(trifluoromethanesulfonyl)amide successfully prevented dendrite formation, the reaction was difficult to reverse. Hence, the researchers intend to explore the benefits of other types of magnesium salts, as well as improve the electrochemical stability of the salt combined with lithium, so that reversal of the reaction is easier. They also hope to eventually achieve a compact and high-capacity battery.

“We aim to show the significantly improved reversibility of lithium deposition/dissolution and to realize stable operation for at least 1,000 cycles,” said Arai. “The ultimate goal is to create batteries that can run for 500 kilometers on a full charge in electric vehicles.”

Such batteries could help society realize a low-carbon future, according the authors.

The article can be found at: Shimizu et al. (2018) Suppressing the Effect of Lithium Dendritic Growth by the Addition of Magnesium Bis(trifluoromethanesulfonyl)amide.


Source: Shinshu University; Photo: Shutterstock.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Asian Scientist Magazine is an award-winning science and technology magazine that highlights R&D news stories from Asia to a global audience. The magazine is published by Singapore-headquartered Wildtype Media Group.

Related Stories from Asian Scientist