Cornell researchers, working with upstate New York battery company Charge CCCV, also known as C4V, have developed a real-time diagnostic approach to drastically improve one of the most expensive and time-consuming stages of lithium-ion battery manufacturing: forming the battery.
The approach can reduce formation time by more than half, free up factory floor space and reduce a manufacturer's overall power use by 10% to 15%, saving up to $100 million annually in large operations, the research team said.
The battery formation process involves a series of initial charge and discharge cycles that create protective layers and help determine how well a battery will perform over its lifetime. The process accounts for roughly one-third of production costs and a quarter of factory floor space.
Research published Oct. 28 in the journal Energy Storage Materials shows how researchers - including lead author and graduate student Jantakan Nedsaengtip, M.S. '25 - used real-time measurements to watch what happens inside batteries during formation. It's a view that manufacturers traditionally lack.
"Evaluating formation processes is typically very trial and error," said the paper's principal investigator Vibha Kalra, the Fred H. Rhodes Professor of Chemical Engineering in the Cornell Duffield College of Engineering. "It can take months to years to effectively evaluate long-term performance because you're letting the battery run for thousands of cycles."
Through the National Science Foundation's NSF Energy Storage Engine in Upstate New York program - based at Binghamton University with Cornell serving as a core partner for technology translation - Kalra's lab teamed up with C4V, which provided battery materials the company wanted to study at their operations in Binghamton, New York.
Kalra, who is also the Kathy Dwyer Marble and Curt Marble Faculty Director of the Cornell Atkinson Center for Sustainability, has spent more than a decade refining techniques and experimental designs that allow researchers to observe batteries while they are in operation. For the C4V collaboration, the team combined operando Raman spectroscopy with operando electrochemical impedance spectroscopy to monitor both the chemistry of the protective interfaces forming inside the battery and changes in their resistance, providing a real-time view of how those layers develop during formation.
The researchers found that a slower charging rate was key to creating a stable interface, producing more uniform, inorganic-rich protective layers. Additionally, they demonstrated evidence that the discharging rate could be increased to accelerate the overall process, with key resistance measurements stabilizing after just 1.5 cycles.
The researchers then translated those observations into two accelerated manufacturing protocols. Testing at C4V's facility showed that both maintained performance comparable to the company's conventional process while reducing formation time by up to about 60%.
"This work demonstrates why strong partnerships between research institutions and cell manufacturers are so important for moving the battery industry forward," said Shalabh Gupta, system engineering manager at C4V. "By combining state-of-the-art operando analytics with the constraints of large-scale manufacturing, we were able to translate fundamental research on solid electrolyte interphase formation into an actionable pathway that can reduce formation time by more than half."
That reduction could have significant implications for freeing up factory floor space and reducing work-in-progress inventory. Formation also accounts for roughly one quarter of a battery plant's electricity consumption, so cutting formation time in half or more could reduce overall power use by an estimated 10% to 15%, according to Gupta. For a factory consuming more than 10-gigawatt-hours annually, the reduction could result in up to $100 million in reduced cell formation costs.
"Academic-industry research projects allow research discoveries like that of Professor Kalra's group to have a much earlier impact," said Stan Whittingham, chief innovation officer for NSF Energy Storage Engine and a 2019 Nobel laureate for his contributions to the development of lithium-ion batteries. "NSF Engine can bring the best teams together as in this case. Formation time is a high-cost part of battery manufacturing, and this work of the Kalra group is a great step forward."
Syl Kacapyr is associate director of marketing and communications for Duffield Engineering.
