The Chicken-and-Egg Conundrum we talk about in reference to electric vehicles (EVs) around here might be a thing of the past if battery technology developed at Oak Ridge National Laboratory in East Tennessee finds its way into electrified autos.
According to an article in Txchnologist, scientist Chengdu Liang and his team have been working on ways to improve battery storage capacity since 2007. What they found was that elemental sulfur– an industrial byproduct– in conjunction with lithium could allow batteries to store four times more energy than conventional lithium-ion batteries.
Liang said, “Our battery is the next generation of energy storage. The materials we developed will be the foundation for batteries for the next 30 to 50 years. It will make a big impact.”
Conventional battery-building uses liquid electrolytes– like the stuff in most traditional car batteries– to conduct electricity between cathodes and anodes. Unable to figure out how to successfully increase battery storage using such traditional liquid-only methods, Liang and the scientists at ORNL reportedly began looking into all-solid batteries that use lithium- and sulfur-rich compounds. Says the article:
It was an approach that had been investigated before but never advanced because of technical problems. So the group designed new molecules that grew crystal structures allowing better conductivity and energy storage throughout the battery. “Our approach is a complete change from the current battery concept of two electrodes joined by a liquid electrolyte, which has been used over the last 150 to 200 years,” he says.
Liang added, “Sulfur is practically free. Not only does it store much more energy than the metallic compounds used in lithium-ion battery cathodes, but a lithium-sulfur device could help recycle a waste product into a useful technology.”
So not only would it give us greater driving range, in theory, but it would be a cleaner technology that wasn’t as reliant on heavy metals.
If you want to really dig into Liang’s work, a study was published here. In layman’s terms, the article laid it out for us:
The researchers demonstrated that their device could maintain a capacity of 1,200 milliamp-hours (mAh) per gram through 300 charge-discharge cycles at 140 degrees Fahrenheit. Traditional lithium-ion batteries, in comparison, have capacities between 140-170 mAh/g.
They explained in a lab release that because lithium-sulfur batteries deliver about half the voltage of lithium-ion versions, this eight-fold increase in capacity demonstrated in their new battery translates into four times the gravimetric energy density of lithium-ion technologies. “Our battery design has real potential to reduce cost, increase energy density and improve safety compared with existing lithium-ion technologies,” he says.
Beyond the energy storage capacity boost, the sulfur-containing battery could be much safer than current liquid-filled batteries, including those that caused brand-new Boeing 787 airliners to be grounded recently.
Liang said, “That liquid electrolyte solution is highly flammable. That’s why we are looking to develop materials that are resistant to fire. We realized that if we used a good solid, then we could get the same or better performance in terms of safety along with performance.”
The new battery technology “still needs major work,” the article said, but fans of EVs that we are, we hope it comes to fruition sooner than later.