The researchers developed a 3D, cross-linked polymer sponge that attaches to the metal plating of a battery anode.
"This project aims to develop the next generation of metal batteries," said Professor Donghai Wang, the principal investigator of the project. "Lithium metal has been tried in batteries for decades, but there are some fundamental issues that inhibit their advancement."
Under additional strain, like in the fast-charging methods desired in electrical vehicles (EVs), lithium ion (Li) batteries are vulnerable to dendritic growth – needle-like formations that can reduce cycle life and potentially cause safety issues – including fires or explosions.
"Our approach was to use a polymer on the interface of Li metal," Prof. Wang explained. The material acts as a porous sponge that not only promotes ion transfer, but also inhibits deterioration.
"This allowed the metal plating to be free of dendrites, even at low temperatures and fast charge conditions," he said.
The researchers conducted modelling work to understand the improvement of Li metal anodes. The practical applications of this work could enable more powerful and stable metal battery technologies integral to everyday life, according to the team.
"In an EV, it could increase the range of a drive before needing a charge by hundreds of miles," said Prof. Wang. "It could also give smartphones a longer battery life."
Looking to the future, the team will explore the practical applications in a large-format battery cell to demonstrate its advantages and feasibility.