We’re mostly familiar with the lithium ion battery, which can be recharged hundreds of times and is shown to work really well in devices such as mobile phones.
However, lithium is already costly and commodity prices will soar if electric vehicles powered with lithium ion batteries turn out to be as popular as is being predicted.
According to Reza Shahbazian Yassar, an associate professor of mechanical engineering-engineering mechanics at Michigan Technological University, sodium may be a good alternative.
“After lithium, it’s the most attractive element to be used in batteries,” Shahbazian-Yassar said.
“It’s also cheap and abundant; seawater is full of it. It has just one drawback: sodium atoms are big, about 70% larger in size than lithium atoms. When the atoms are too big, that’s problematic.”
This is because they can cause a battery’s electrodes to wear out faster.
“Imagine bringing an elephant through the door into my office. It’s going to break down the walls,” said Shahbazian-Yassar.
Before a long-lasting rechargeable sodium battery can be developed, scientists need to better understand these challenges and develop solutions.
With a $417,000 National Science Foundation grant, Shahbazian-Yassar is leading that effort at Michigan Tech.
“We have an opportunity to tackle some of the fundamental issues relating to charging and discharging of batteries right here,” he said. “We have a unique tool that lets us observe the inside of a battery.”
Using a transmission electron microscope, Shahbazian-Yassar and his team can peer inside and see how a battery is charging and discharging at the atomic level.
“We will study these fundamental reactions and find out what materials and electrodes will do a better job hosting the sodium.”
He suggests that sodium ion batteries would not have to be as good as lithium ion batteries to be competitive; they would just need to be good enough to satisfy the consumer.
“That way they could make electric cars more affordable, and thus more attractive,” said Shahbazian-Yassar.
“They could reduce our dependence on fossil fuels, particularly if the batteries were charged using renewable energy sources. That would lead to two laudable goals: greater energy independence and less pollution worldwide.”
