Research into a battery with innovative lithium metal negative electrodes is being touted as having potential to triple the energy density of electric cars in coming years.
This could mean three-times the EV range from a battery of the same size as one today, according to work done at the University of Waterloo in Waterloo, Ontario, Canada, and led by Quanquan Pang, now a post-doctoral fellow at the Massachusetts Institute of Technology.
“This will mean cheap, safe, long-lasting batteries that give people much more range in their electric vehicles,” said Pang, who led the research while he was a PhD candidate at Waterloo.
To develop the technology, researchers and Pang along with supervisor Linda Nazar, a professor of chemistry and chemical engineering at Waterloo, had two challenges to overcome.
“The first challenge involved a risk of fires and explosions caused by microscopic structural changes to the lithium metal during repeated charge-discharge cycles,” said a statement issued by the university. “The second involved a reaction that creates corrosion and limits both how well the electrodes work and how long they last.”
Both problems were solved when researchers added a compound comprised of phosphorus and sulfur elements to the liquid electrolyte. This reacted with the lithium metal electrode to spontaneously coat it with an extremely thin protective layer
“We wanted a simple, scalable way to protect the lithium metal,” said Pang. “With this solution, we just add the compound and it works by itself.”
A paper on the research was published today in the journal Joule, but Pang did not predict time to market or commercialization readiness at this stage.
“This research is still in the early stage of research on lithium metal batteries,” said Pang in response to a query by HybridCars.com. “We have not gone through commercialization evaluation, but it still requires a couple of years before turning into a mature technology, as refining fabrication procedures and materials screening are necessary. To put a lithium metal electrode in an electrical car, we also need extreme care on the safety.”
Otherwise, the researchers say the novel approach is being developed without compromising safety or reducing lifespan with an eye on automotive applications.