ORNL component reduces cost and supply chain constraints for fast-charging EV batteries
July 2, 2025
Researchers at the US Department of Energy’s Oak Ridge National Laboratory, Tennessee, have demonstrated how to manufacture a battery with both superior energy density and a lasting ability to handle extremely fast charging by integrating a new type of current collector. This enables restoring at least 80% of battery energy in 10 minutes.
ORNL’s study results, published in *Energy & Environmental Materials,* focus on the potential of the metal-polymer current collector to revolutionise the roll-to-roll battery manufacturing process and significantly advance the performance metrics of lithium-ion batteries in electric vehicle applications.
“This provides a significant savings on near-critical materials, because much less copper and aluminium are needed,” said lead researcher Georgios Polyzos. “At the same time, this will greatly enhance the energy density achievable with a ten-minute charge.”
A current collector conducts electricity from the active material within the battery to an external circuit. Current collectors are generally made of metal foil, with one at each pole of the electrode: copper for the anode and aluminium for the cathode. The metals add weight to the battery, increasing the overall weight of the car and the amount of energy required to move it.
The novel current collector, made by industry partner Soteria Battery Innovation Group, Greenville, South Carolina, is a polymer sandwiched between very thin layers of copper or aluminium. ORNL researchers reported that this new component can reduce current collector costs by 85%, pack in 27% more energy for longer trips, and maintain significant energy density after a thousand cycles, even under extreme fast charging conditions that can degrade battery materials more rapidly over time. The new current collector performs as well as its conventional counterpart at about a quarter of the weight, enabling an EV to travel farther on the same charge.
To ensure the technology could be scaled up for commercialisation, ORNL researchers made coin and pouch cell batteries using industry-standard processes at ORNL’s open-access Battery Manufacturing Facility. Polyzos said the team pinpointed parameters for successfully incorporating the thinner material into the roll-to-roll production process, despite its being more prone to wrinkling. Other experimental current collectors have generally required expensive and complex manufacturing processes that are incompatible with standard roll-to-roll methods.
Brian Morin, CEO of South Carolina-based Soteria, said ORNL has helped the company understand how to achieve rapid battery charging with the technology, despite increased physical resistance from the plastic film.
“We take 80% of the metal out, which makes it harder to do things quickly,” Morin said. “But they’ve shown that you can still get fast charge and discharge. Soteria’s testing has shown the polymer also makes the battery safer. If there is an internal short circuit that produces a brief rush of energy, it eats the plastic film, which pulls the metal away. Our current collector acts like a circuit breaker inside the battery and eliminates about 90% of lithium-ion battery fires caused by short circuits.”
The metalised polymer current collector research was funded through DOE’s Advanced Materials and Manufacturing Technologies Office (AMMTO). Other ORNL researchers involved in the project include Sergiy Kalnaus, Sabine Neumayer, Wheatley Steenman and Jaswinder Sharma.
‘Metalized Polymer Current Collector for High-Energy Lithium-Ion Batteries with Extreme Fast-Charging Capability’ is available here.
