A conductive polymer covering known as HOS-PFM, developed by Berkeley Lab researchers, may enable more potent, long-lasting lithium-ion batteries for electric vehicles.
Gao Liu, a senior scientist in Berkeley Lab’s Energy Technologies Area, said that the development “opens up a new approach to developing EV batteries that are more affordable and easy to manufacture”.
The HOS-PFM coating simultaneously conducts ions and electrons. This prolongs battery life and ensures high charge/discharge rates for the battery. According to Liu, the coating also shows promise as a battery adhesive that could increase a lithium-ion battery’s typical lifespan from 10 to about 15 years.
Liu and his team coated aluminum and silicon electrodes with HOS-PFM and then tested the electrodes’ performance in a lithium-ion battery configuration to show off the material’s superior conductive and adhesive properties.
Due to their potential for high energy storage capacity and lightweight profiles, silicon and aluminum are promising electrode materials for lithium-ion batteries. However, after numerous charge/discharge cycles, these inexpensive and plentiful materials quickly degrade.
In experiments at the Advanced Light Source and the Molecular Foundry, the researchers demonstrated that the HOS-PFM coating significantly prevents silicon- and aluminum-based electrodes from degrading during battery cycling while delivering high battery capacity over 300 cycles, a performance rate that’s on par with today’s state-of-the-art electrodes.
Because silicon-based lithium-ion cells typically only have a finite amount of charge/discharge cycles and calendar life, Liu said the results are remarkable. In the journal Nature Energy, the researchers recently published a description of these findings.
The HOS-PFM coating might enable the use of electrodes with up to 80% silicon content. According to Liu, such a high silicon content could boost lithium-ion batteries’ energy density by at least 30%. And since silicon is less expensive than graphite, which is currently the industry standard for electrode materials, more entry-level electric vehicles may be available in the future, he continued. The team will then collaborate with businesses to scale up HOS-PFM for mass production.
