Ohio State scientists are researching new technology that would allow for a more powerful type of battery for electric cars. The batteries would last longer, charge quicker and prevent discharge.
Conventional batteries store ions in electrodes, which slows down the speed of charging down. The new battery, also called the radox transistor battery, stores ions in electrolytes.
Vishnu-Baba Sundaresan, an assistant professor of mechanical and aerospace engineering who is leading the study, said electrolytes can be pumped out and refilled, which is similar to adding gasoline to a car. This allows drivers to charge batteries quickly and repeatedly, which is not possible with conventional batteries.
“So, for example, let’s say that you are driving from (Columbus) to Chicago. You can stop somewhere, dump out the electrolytes that have already been used, and add new electrolytes in. You can keep driving,” Sundaresan said.
The technology is based on a “smart” membrane separator, a tiny plastic membrane that enables faster and safer charging by regulating ionic transportation in the battery. With an external voltage, the membrane can be turned on or off to allow or stop the flow of ions.
Sundaresan said one of the biggest issues with current batteries is that their charges run out quickly.
“It’s a revelation, for us, at least, to think about the fact that we are spending more time on the charging station than driving the vehicle itself,” Sundaresan said.
Traditional electric car batteries hit a performance limit of 0.4 miles per minute spent charging. This limitation is caused by slow charging, which happens because some stored energy gets lost when recharging.
Travis Hery, doctoral student of mechanical engineering and researcher involved with the study, sees the membrane as a great advantage.
“We can actively control the way in which ions are flowing across the membrane,” Hery said.
In conventional batteries, leaked energy transfers to heat, and overheating causes a battery to explode or stop functioning.
The control of ion flow would preserve the state of charge and prevent leakage between anode and cathode, an event called self-discharge. The smart membrane can also shut down ionic movement and stop batteries from catching fire.
Sundaresan and his team hope to have their own startup to change how batteries function for electric cars.
“The motivation for what we are doing is to develop a fundamentally different way of thinking about electrical batteries for vehicles,” Sundaresan said.