Clear advantage in glass batteries
The inventor of the lithium-ion battery is now trying to make it redundant.
Researchers at the University of Texas have unveiled a promising new lithium- or sodium-glass battery technology.
“I think we have the possibility of doing what we’ve been trying to do for the last 20 years,” says John Goodenough, coinventor of the lithium-ion battery and emeritus professor at the university.
“That is, to get an electric car that will be competitive in cost and convenience with the internal combustion engine.”
But Goodenough says the glass battery technology could be used at grid level to store solar and wind power.
New battery ideas emerge fairly rapidly in engineering labs around the world, but MIT materials science and engineering professor Donald Sadoway says this one seems different.
“When John Goodenough makes an announcement, I pay attention. He’s top in the field and really a fantastic scientist. So, his pronouncements are worth listening to,” he said.
The battery uses a form of glass imbued with reactive alkali metals like lithium or sodium as its electrolyte – which allows ions to travel from the cathode to electrode and back as the battery charges and discharges.
The team’s latest research paper suggests the doped glass electrolyte will be an exciting new medium for battery chemistry and physics.
A lithium- or sodium-glass battery should have about three times the energy storage capacity of a comparable lithium-ion battery, but is neither flammable nor volatile, and does not appear to build up the creeping ‘dendrites’ that affect lithium-ions and cause them to lose capacity and short out.
Lithium-glass battery co-developer Maria Helena Braga says the glass battery charges in “minutes rather than hours”, because it has a far greater capacity to store energy in the electric field.
Braga says early tests suggest the technology could run through thousands of charge-discharge cycles, and keep performing in both extremely cold and hot weather from -20º C to 60º C.
Additionally, the team says if the battery uses sodium instead of lithium, it could be produced more reliably and sustainably.
“Addressing the [battery] safety issue is, I think, a giant step forward,” Dr Sadoway said.
“People have been talking about solid-state electrolytes for 20 years. But I can’t point to a commercial product yet…. If he can give us an electrolyte that is devoid of these flammable, organic solvents, that’s salutary in my opinion.”
Dr Goodenough says the anode and electrolyte designs are essentially ready for commercial production, but it will need an improved cathode setup before it reaches the commercial marketplace.
“The next step is to verify that the cathode problem is solved,” Goodenough says.
“And when we do [that] we can scale up to large-scale cells. So far, we’ve made jelly-roll cells, and it looks like they’re working fairly well. So I’m fairly optimistic we’ll get there. But the development is going to be with the battery manufacturers. I don’t want to do development. I don’t want to be going into business. I’m 94. I don’t need the money.”