These scanning electron microscope images show how the HOS-PFM coating can significantly prevent aluminum-based electrodes from degrading during battery cycling while delivering high battery capacity over 300 cycles. Figures A and B show aluminum on a copper bilayer device before (A) and after (B) battery cycling. Figure C shows a copper tri-layer device with HOS-PFM coating after battery cycling. Image: Gao Liu/Berkeley Lab. Courtesy of Nature Energy.
These scanning electron microscope images show how the HOS-PFM coating can significantly prevent aluminum-based electrodes from degrading during battery cycling while delivering high battery capacity over 300 cycles. Figures A and B show aluminum on a copper bilayer device before (A) and after (B) battery cycling. Figure C shows a copper tri-layer device with HOS-PFM coating after battery cycling. Image: Gao Liu/Berkeley Lab. Courtesy of Nature Energy.

Scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a conductive polymer coating – called HOS-PFM – that could lead to longer lasting, more powerful lithium-ion batteries for electric vehicles (EVs).

“The advance opens up a new approach to developing EV batteries that are more affordable and easy to manufacture,” said Gao Liu, a senior scientist in Berkeley Lab’s Energy Technologies Area.

The HOS-PFM coating conducts both electrons and ions at the same time, thereby ensuring battery stability and high charge/discharge rates while enhancing battery life. The coating also shows promise as a battery adhesive that could extend the lifetime of a lithium-ion battery from an average of 10 years to about 15 years, Liu added.

To demonstrate HOS-PFM’s superior conductive and adhesive properties, Liu and his team coated aluminum and silicon electrodes with HOS-PFM and tested their performance in a lithium-ion battery setup.

Silicon and aluminum are promising electrode materials for lithium-ion batteries because of their potentially high energy-storage capacity and lightweight profiles. But these cheap and abundant materials quickly wear down after multiple charge/discharge cycles.

During experiments at Berkeley Lab’s Advanced Light Source and Molecular Foundry, the researchers demonstrated that the HOS-PFM coating can prevent silicon- and aluminum-based electrodes from degrading during battery cycling while delivering high battery capacity over 300 cycles. This is a performance rate that’s on par with today’s state-of-the-art electrodes.

The results are impressive, Liu said, because silicon-based lithium-ion cells typically last for a limited number of charge/discharge cycles and calendar life. The researchers report their findings in a paper in Nature Energy.

The HOS-PFM coating could allow electrodes containing as much as 80% silicon to be used in lithium-ion batteries, increasing their energy density by at least 30%, Liu said. And because silicon is cheaper than graphite, the standard material for electrodes today, cheaper batteries could significantly increase the availability of entry-level EVs, he added.

The team next plans to work with companies to scale up HOS-PFM for mass manufacturing.

This story is adapted from material from Lawrence Berkeley National Laboratory, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.