Reviewed by Lexie CornerApr 2 2025
Engineers from the University of Michigan have developed a modified manufacturing process for electric vehicle batteries that aims to enable fast charging in cold weather and improve long-range performance, addressing common concerns among potential EV buyers.
Engineering student Chloe Acosta plugs in an EV for charging in snowy weather on the University of Michigan’s North Campus. EV charging becomes less efficient in colder weather, but a new strategy for manufacturing battery electrodes could enable charging in 10 minutes in temperatures as cold as -10 ºC. Image credit: Marcin Szczepanski, Michigan Engineering
We envision this approach as something that EV battery manufacturers could adopt without major changes to existing factories. For the first time, we have shown a pathway to simultaneously achieve extremely fast charging at low temperatures, without sacrificing the energy density of the lithium-ion battery.
Neil Dasgupta, Associate Professor and Study Corresponding Author, Mechanical Engineering and Materials Science and Engineering, University of Michigan
At temperatures as low as 14 ºF (-10 ºC), lithium-ion EV batteries manufactured using this modified process can charge five times faster. The modified structure and coating prevent the formation of lithium plating on the battery's electrodes, which typically degrades performance.
As a result, these modified batteries retain 97 % of their capacity after 100 fast charges at extremely low temperatures.
Current EV batteries use a liquid electrolyte to transport lithium ions between electrodes for power storage and release. However, at lower temperatures, the movement of these ions slows, which reduces both battery power and charging speed.
To increase range, automobile manufacturers have thickened battery cell electrodes. While this provides longer driving distances between charges, some lithium becomes inaccessible, slowing charging and reducing power efficiency for the given battery weight.
Previously, Dasgupta's team improved battery charging capacity by creating pathways in the anode, the electrode that receives lithium ions during charging, with a size of about 40 µm. By using lasers to create these pathways in the graphite, lithium ions could more quickly locate spots to lodge, resulting in more consistent charging.
While this method greatly accelerated charging at room temperature, charging in cold conditions remained ineffective. The team identified that a chemical layer forms on the electrode surface from reactions with the electrolyte, which is the main issue.
Dasgupta compared the behavior to butter, noting that a knife can cut through it whether it is warm or cold, but is much harder to cut when cold. If you try to fast charge through that layer, lithium metal will build up on the anode like a traffic jam.
That plating prevents the entire electrode from being charged, once again reducing the battery’s energy capacity.
Manoj Jangid, Senior Research Fellow and Study Co-Author, Mechanical Engineering, University of Michigan
The team needed to prevent the formation of the surface layer. They accomplished this by applying a glassy, approximately 20 nm-thick layer of lithium borate-carbonate to the battery. This coating significantly improved cold charging, and when combined with the channels, the test cells charged five times faster in subfreezing temperatures.
By the synergy between the 3-D architectures and artificial interface, this work can simultaneously address the trilemma of fast charging at low temperature for long-range driving.
Tae Cho, Ph.D. Graduate and Study First Author, Mechanical Engineering, University of Michigan
As consumers increasingly seek environmentally friendly options, EVs have become more common on the roads over the past 20 years. However, a recent AAA survey suggests that sustaining this momentum is challenging. The percentage of American adults who said they would be “likely” or “very likely” to purchase a new or used EV dropped from 23 % in 2023 to 18 % in 2024.
Additionally, 63 % of respondents reported that they were “unlikely” or “very unlikely” to buy an EV as their next car. Concerns such as range reductions during winter and slower charging times, which were widely discussed during the January 2024 cold snap, are among the issues.
“Charging an EV battery takes 30 to 40 minutes even for aggressive fast charging, and that time increases to over an hour in the winter. This is the pain point we want to address,” Dasgupta said.
Follow-up efforts to create factory-ready processes are being funded by the Michigan Economic Development Corporation through the Michigan Translational Research and Commercialization (MTRAC) Advanced Transportation Innovation Hub.
The Michigan Center for Materials Characterization researched the devices, which were constructed in the U-M Battery Lab.
With assistance from U-M Innovation Partnerships, the team has applied for patent protection. The channel technology has been licensed by Arbor Battery Innovations, which is also working on its commercialization. Arbor Battery Innovations is financially owned by Dasgupta and the University of Michigan.
Journal Reference:
Cho, T. H., et al. (2025) Enabling 6C fast charging of Li-ion batteries at sub-zero temperatures via interface engineering and 3D architectures. Joule. doi.org/10.1016/j.joule.2025.101881.