The team, led by Susumu Arai, a professor of the department of materials chemistry and head of Division for Application of Carbon Materials at the Institute of Carbon Science and Technology at Shinshu University, used a type of magnesium salt capable of combining with lithium to stop the dendritic branching. While it worked, it is difficult to reverse, which is necessary in rechargable batteries.
Dendrites can grow when the cell is charged and discharged, creating short circuits that lead to thermal runaway and can lead to fires.
Now the researchers are studying the benefits of other types of magnesium salts, as well as working to improve the electrochemical stability of the salt combined with lithium to make reversal easier. The researchers hope to solve the issues with this plating technology and eventually achieve a compact and high-capacity battery that could give electric vehicles a range of over 500km.
"Lithium metal is inherently unsuitable for use in rechargeable batteries due to posing certain safety risks," said Arai. "Repeated lithium deposition/dissolution during charge/discharge can cause serious accidents due to the deposition of lithium dendrites that penetrate the separator and induce internal short-circuiting."
"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. "In contrast, our strategy of adding magnesium salt is extremely simple.""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 to run for 500 kilometers with full charge in electric vehicles."