In the latest battery breakthrough claim of the week, researchers from the University of Waterloo released a new paper claiming a breakthrough involving the use of negative electrodes made of lithium metal.
They claim that it has the potential to “dramatically increase battery storage capacity,” which could triple the range of electric vehicles.
The main issue with Li-metal batteries is the quick degradation due to dendrites forming in the cells.
Quanquan Pang, who led the research while he was a PhD candidate at Waterloo (now a post-doctoral fellow at MIT), claims to have solve the issue by “adding a chemical compound made of phosphorus and sulfur elements to the electrolyte liquid that carries electrical charge within batteries.”
They claim that the compound reacts with the lithium metal electrode in an already assembled battery to “spontaneously coat it with an extremely thin protective layer.”
It enables them to use lithium metal electrodes in battery cells and take advantage of their greater storage capacity without the safety risks and faster degradation.
“This will mean cheap, safe, long-lasting batteries that give people much more range in their electric vehicles,”
He and his team published their findings in the journal Joule this week.
In the paper, they claim to have completed “over 400 cycles at 5-C rate” in prototype cells and that they have achieved a “close to 100% coulombic efficiency.”
As usual, we need to be careful with “battery breakthrough” claims. It’s relatively easy to make a battery capable of fast-charging or having a high energy density, or a battery that is inexpensive or durable, but it’s extremely hard to make a battery good at all those things, which is the holy grail of battery technology.
What this team at the University of Waterloo did is apparently make lithium metal electrodes work well in the lab, but will it ever turn into a viable commercial product? We don’t know.