Missouri S&T’s chargers can power an EV in 10 minutes
Researchers from Missouri S&T and three private companies will combine their expertise to create charging stations for electric vehicles that could charge a car in less than 10 minutes – matching the time it takes to fill up a conventional vehicle with gasoline.
“The big problem with electric vehicles is range, and it’s not so much range as range anxiety. People are nervous about not being able to get where they’re going,” says Missouri S&T professor of electrical and computer engineering Dr. Jonathan Kimball. “With a conventional vehicle, you pull up, get gas, and in 10 minutes you’re back on the road.”
Kimball is leading a team that received a US$2.9-million grant from the US Department of Energy (DOE) to develop an extreme fast-charging system for EVs over the next three years.
Each organisation involved will provide matching funds equal to what they receive from the DOE. Missouri S&T will receive US$1.8 million and provide another US$1.8 million in cost-sharing. Three corporate partners will receive US$1.1 million and provide another US$1.1 million in cost sharing.
The project partners include Ameren, Missouri’s largest electric power provider; LG Chem Michigan, a global manufacturer of lithium-ion batteries; and Bitrode, a St. Louis-based maker of laboratory-grade battery testing equipment.
Kimball says the group hopes to make EVs more user-friendly by significantly reducing charging time. Most EV chargers on the market today require anywhere from a few hours to overnight to fully charge a vehicle. Even Tesla’s Supercharger stations take up to an hour to fully charge a car.
Kimball says there will be challenges to building these fast charging stations. The first challenge is whether or not the batteries can withstand such speedy charges. Overcharging a lithium battery could lead to overheating and fire, he says, and even if that scenario is avoided, the battery could still be damaged and wear out faster.
To address these challenges, the team will develop a model-based protocol for monitoring what researchers call the battery’s “state of charge” and “state of health.”
Quickly pulling large amounts of electricity from the power grid is another challenge for researchers, says Kimball. He estimates that charging a Li-ion car battery in 10 minutes will take about 300-400 kW, and adding several cars charging simultaneously could add up to more than 1 MW in needed power.
Dr. Rui Bo, S&T assistant professor of electrical and computer engineering, says the sudden high current needed for fast charging would affect the power quality from the utility provider. That means it could affect other customers that also need power.
Bo and Kimball hope to bypass that instant pull on the electric grid by first connecting to a charged battery and then ramping up to connecting directly to the 12-kV distribution network.