Scientists at Empa, the Swiss Federal Laboratory for Material Science and Technology, are developing graphene-based supercapacitors designed for industrial-scale production, aiming to deliver higher energy density and conductivity than current carbon-based devices. The project seeks to create printable electrodes suitable for roll-to-roll manufacturing for applications such as electric vehicles, renewable energy systems and industrial machinery.
Supercapacitors store energy electrostatically, enabling rapid charge and discharge cycles, but typically offer lower energy density than batteries. “Supercapacitors store energy electrostatically by depositing as many charged particles as possible on the surface of the electrode,” said Jakob Heier, head of Empa’s Functional Thin Film Solution Processing group. While most commercial designs use activated carbon for its high surface area, Empa said its low electrical conductivity and the use of binders in production reduce storage capacity and performance.
The Empa team uses two types of graphene with different structural properties to precisely control pore size and layer spacing, improving ion accessibility and conductivity. “If the pore size of the electrode is matched to the size of the ions in the electrolyte, the energy density of the supercapacitor increases dramatically,” said postdoctoral researcher Sina Azad. The graphene is produced using a proprietary exfoliation process from a previous project, resulting in a printable ink compatible with existing industrial processes.
The research, supported by Bridge, a joint programme of the Swiss National Science Foundation and Innosuisse, runs until 2028 and aims to produce working supercapacitor prototypes, optimise manufacturing steps and identify compatible electrolytes. “We want to develop a real, reliable product,” Azad said. “At the end of the project, we want to bring our technology to market, either with industrial partners or with our own spin-off.”