Affordable electric car battery aims to end ‘range anxiety’

A new lithium iron phosphate battery for electric cars offers a range of 250 miles with the ability to recharge in 10 minutes.

It could make “range anxiety,” the fear of running out of power before being able to recharge an electric car, a thing of the past, researchers say.

“We developed a pretty clever battery for mass-market electric vehicles with cost parity with combustion engine vehicles,” says Chao-Yang Wang, chair of mechanical engineering, professor of chemical engineering, professor of materials science and engineering, and director of the Electrochemical Engine Center at Penn State. “There is no more range anxiety and this battery is affordable.”

The battery should be good for 2 million miles in its lifetime, researchers say.

As reported in Nature Energy, the key to long-life and rapid recharging is the battery’s ability to quickly heat up to 140 degrees Fahrenheit, for charge and discharge, and then cool down when the battery is not working.

“The very fast charge allows us to downsize the battery without incurring range anxiety,” says Wang.

The battery uses a self-heating approach previously developed in Wang’s center. The self-heating battery uses a thin nickel foil with one end attached to the negative terminal and the other extending outside the cell to create a third terminal.

Once electrons flow it rapidly heats up the nickel foil through resistance heating and warm the inside of the battery. Once the battery’s internal temperature is 140 degrees F, the switch opens and the battery is ready for rapid charge or discharge.

Wang’s team modeled the new battery using existing technologies and innovative approaches. They suggest that using this self-heating method, they can use low-cost materials for the battery’s cathode and anode and a safe, low-voltage electrolyte. The cathode is thermally stable lithium iron phosphate, which does not contain any of the expensive and critical materials like cobalt. The anode is made of very large particle graphite, a safe, light, and inexpensive material.

Because of the self-heating, the researchers say they don’t have to worry about uneven deposition of lithium on the anode, which can cause dangerous lithium spikes.

“This battery has reduced weight, volume, and cost,” says Wang. “I am very happy that we finally found a battery that will benefit the mainstream consumer mass market.”

The smaller batteries can produce a large amount of power upon heating—40 kilowatt hours and 300 kilowatts of power, according to Wang. An electric vehicle with this battery could go from zero to 60 miles per hour in 3 seconds and would drive like a Porsche, he says.

“This is how we are going to change the environment and not contribute to just the luxury cars,” says Wang. “Let everyone afford electric vehicles.”

The US Department of Energy’s Office of Energy Efficiency and Renewable Energy and the William E Diefenderfer Endowment supported the research.

Source: Penn State