3D, Cross-Linked Poymer Sponge Attaches to Battery Anode, Creates Improved Lithium Metal Batteries

Researchers at Penn State have developed a three-dimensional, cross-linked polymer sponge that attaches to the metal plating of a battery anode in order to create longer-lasting, faster-charging, and safer lithium metal batteries. The work was funded by the U.S Department of Energy and was recently published in Nature Energy.

“This project aims to develop the next generation of metal batteries,” said Donghai Wang, professor of mechanical engineering and 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.”

The fast-charging methods desired in electrical vehicles cause lithium ion (Li) batteries additional strain which can lead to dendritic growth — needle-like formations that can reduce cycle life and energy density and potentially cause safety issues — including fires or explosions.

“Our approach was to use a polymer on the interface of Li metal,” 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 condition.”

The project brought together researchers from different disciplines within the University.

“The collaboration in this cohort really helped drive this paper forward,” Wang explained. “It allowed us to examine the different aspects of this problem, from materials science, chemical engineering, chemistry, and mechanical engineering perspectives.”

According to the researchers, this work could enable more powerful and stable metal battery technologies integral to everyday life. The team also observed dendrite-free morphology in sodium and zinc anodes, which indicates a broader promise of the approach.

“In an electric vehicle, it could increase the range of a drive before needing a charge by hundreds of miles,” said Wang. “It could also give smartphones a longer battery life.”