Researchers at the Korea Institute of Materials Science (KIMS), working with the Korea Electrotechnology Research Institute (KERI), have developed a dry electrode manufacturing technology that eliminates the need for polytetrafluoroethylene (PTFE), a material commonly used in existing dry battery production processes.
The research, published in Energy Storage Materials, could support the development of higher-energy-density batteries for electric vehicles (EVs) and energy storage systems while reducing manufacturing emissions and production costs.
New Electrode Design Eliminates PTFE
The research team, led by Jihee Yoon of KIMS and Insung Hwang of KERI, developed Korea’s first shape-controlled graphite granule-based dry electrode process using a carboxymethyl cellulose-styrene butadiene rubber (CMC-SBR) binder system instead of PTFE.
PTFE has traditionally been used as the primary binder in dry electrodes because it helps hold electrode materials together. However, it has been associated with performance limitations in battery anodes and growing environmental concerns related to fluorinated materials.
To overcome these challenges, the researchers redesigned the structure of graphite particles by producing composite graphite granules through a spray-drying process.
Rather than forming the highly aligned graphite structures typically seen in conventional electrodes, the new manufacturing method creates granules with a randomly oriented internal structure.
According to the researchers, this isotropic architecture allows lithium ions to move more efficiently in multiple directions, including through the thickness of the electrode, reducing transport limitations that can affect thick electrodes.
Laboratory testing showed the new dry anode delivered improved fast-charging capability and better long-term cycling stability than conventional slurry-based electrodes.
The researchers also reported enhanced lithium-ion diffusion under high-energy-density operating conditions, suggesting the technology could support thicker electrode designs capable of increasing battery capacity without sacrificing charging performance.
Potential for Large-Scale Manufacturing
Because the process uses the CMC-SBR binder system already widely employed in commercial wet-electrode manufacturing, the researchers said the technology could be integrated into existing battery production lines more readily than alternative approaches.
The dry manufacturing process also minimizes the use of organic solvents and reduces drying requirements, offering potential reductions in both production costs and carbon emissions.
Senior researcher Jihee Yoon said the technology could help address limitations associated with current dry electrode manufacturing.
“This technology presents a new approach capable of overcoming the limitations of conventional PTFE-based dry-electrode processes.”
“We expect it to be highly applicable to next-generation EV batteries that require both high energy density and fast-charging performance.”
The team said the technology could find applications in electric vehicles, energy storage systems and other next-generation battery technologies requiring high energy density and rapid charging capability.