How Battery Technology is Charging Ahead
Innovations in microchips and semiconductors keep pushing advances in mobile computing devices, yet the battery technology that helps power those same devices remains stagnated. By some accounts, lithium-ion batteries haven’t changed much over the past 15 years.
That could change soon with developments in next-generation solid-state batteries. Vacuum manufacturer Dyson’s recent investment in a solid-state battery research lab has raised the profile of the emerging technology. And academic researchers and industry heavyweights such as Samsung are working to develop better batteries.
Holding the promise of longer life and higher performance, solid-state batteries are designed to be unbreakable, operate in frigid temperatures and are safer than current lithium-ion batteries, which use flammable liquid electrolytes that can overheat and cause fires.
“Solid-state is one of the promising directions for current lithium-ion,” says Yan Wang, a senior postdoctoral associate at the Massachusetts Institute of Technology. “The main issue is finding the solid electrolytes that will replace the current use of liquid electrolytes.”
It's All About the Electrolytes
Potential improvement in power density of solid-state batteries over lithium-ion
SOURCE: Nature Materials, “Design Principles for Solid-State Lithium Superionic Conductors,” August 2015
Batteries have three parts: two terminals or electrodes — an anode (negative) and a cathode (positive) – made up of different chemicals; a separator; and the electrolyte, which is typically a liquid organic solvent that transports charged particles between the terminals during charging and discharging.
MIT and Samsung researchers recently had a breakthrough, identifying “suitable solid-state electrolytes with high ion conductivity,” Wang says. “The research found a structural descriptor for solid-state super-ionic conductors, and created a shortcut for discovery of new solid electrolyte materials,” he says.
The journal Nature Materials recently reported the results of the research, which was conducted by Wang, MIT visiting professor Gerbrand Ceder (currently at the University of California, Berkley and Lawrence Berkeley National Laboratory) and five other researchers.
The Future of Battery Tech is Unwritten
Lithium-ion batteries have led to revolutions in consumer electronics, electric vehicles and grid storage, but face limitations in cost and performance, according to Cosmin Laslau, an analyst with Lux Research in Boston. “Incremental improvements will extend their dominance into the next decade,” he says.
But the future belongs to technologies such as solid-state batteries, which will make inroads into the transportation arena and eventually dominate consumer electronics, including advanced smartphones, Internet of Things devices, tablets and wearable devices. The technology will find special niche use in military and medical institutions as well, though it isn’t likely to have a significant impact on society until 2020 and beyond, Laslau predicts.
“Now that we have the solid, work needs to be done on the interface between the electrolyte and the cathode and anode,” says Wang of efforts to make the battery more stable and ensure it can be used through hundreds of cycles.
Researchers are also working to find suitable ways to produce solid-state batteries on a large scale. These issues of interface design and manufacturing are complex problems that have to be addressed before there is full-scale production, Wang notes.
Laslau agrees. “We have definitely seen some acquisitions where companies are acquiring intellectual property, some interesting technologies and research teams,” he says. “But there aren’t mass production facilities set up yet, so a lot of work still needs to be done on fully scaling up this technology.”