Researchers have introduced a new lithium-ion battery design that could power longer-lasting electric vehicles.
Developed by researchers at the University of Surrey’s Advanced Technology Institute (ATI), the novel lithium-ion battery anode delivers some of the highest energy storage capacities reported for silicon–carbon nanotube systems, while maintaining stability over hundreds of charge cycles.
The team developed a new “Vertically Integrated Silicon–Carbon Nanotube” (VISiCNT) structure.
Design grows dense forests of carbon nanotubes
The design grows dense forests of carbon nanotubes directly onto copper foil and coats them with a thin layer of silicon, creating a flexible, conductive scaffold that can absorb expansion while maintaining performance.
The resulting anode can store a very large amount of energy for its weight. In laboratory tests, it stored more than 3500 milliampere-hours per gram – close to the maximum possible for silicon and far higher than the graphite (370 mAh/g) used in today’s batteries. It also demonstrated improved stability and performance over repeated charge cycles, according to a press release.
“There’s been a growing push for battery innovation, as many of today’s technologies are limited by how much energy batteries can store. Our VISiCNT design offers a practical route to harness silicon’s huge storage capability without sacrificing cycle life,” said Dr Muhammad Ahmad.
“This is a much-needed breakthrough, delivering very high capacity, fast charging and long-term durability, while bringing us closer to batteries that can power electric vehicles and everyday devices for much longer on a single charge.”
A key advantage of the new approach is that the carbon nanotubes are grown directly onto copper – the material already used in commercial batteries – using a scalable manufacturing process. This could make it easier to integrate the technology into existing industrial production lines, as per the release.
“This work is an important step towards bringing CNT-silicon anodes out of the lab and into real-world manufacturing,” said Professor Ravi Silva, Distinguished Professor, Interim Director – Institute for Sustainability (IfS), Director – Advanced Technology Institute (ATI).
“We can grow carbon nanotube structures directly onto copper foil at speed and tailor the silicon layer for stability, meaning this approach could be integrated into existing battery production lines with minimal disruption.”
Technology has clear potential not just for EVs, but also for grid storage
Silva also underlined that the technology has clear potential not just for electric vehicles, but also for grid storage and smaller batteries used in microelectronics.
“We are very proud to present yet another CNT technology following our initial research in delivering the world’s darkest material, VANTA-Black via the university spin-out Surrey NanoSystems Ltd., which is showing real-world impact of fundamental research funded by UKRI.”
