Solid-state lithium-ion batteries based on foil-based negative electrodes

From pv magazine global

When used in a conventional lithium-ion battery, aluminum fractures and fails within a few charge-discharge cycles, due to expansion and contraction as lithium travels in and out of the material. The material’s potential application in batteries was investigated in the past, but to no avail.

Now, researchers at the Georgia Institute of Technology in the United States have developed lab-scale lithium-ion battery cells with non-pre-lithiated aluminum-foil-based negative electrodes with improved energy density and stability.

“This is a story about a material that was known about for a long time, but was largely abandoned early on in battery development,” said Associate Professor Matthew McDowell. “But with new knowledge, combined with a new technology — the solid-state battery — we’ve figured out how we can rejuvenate the idea and achieve really promising performance.”

Instead of using pure aluminum in the foils, which would fail rapidly when tested in batteries, the research team added small amounts of other materials to the aluminum to create foils with particular “microstructures,” or arrangements of different materials. They tested over 100 different materials to understand how they would behave in batteries.

The new aluminum foil anode demonstrated markedly improved performance and stability when implemented in solid-state batteries, as opposed to conventional lithium-ion batteries. The lab-scale cells deliver hundreds of stable cycles with practically relevant areal capacities at high current densities (6.5 mA cm⁻²)

“One of the benefits of our aluminum anode that we’re excited about is that it enables performance improvements, but it also can be very cost-effective,” McDowell said. “On top of that, when using a foil directly as a battery component, we actually remove a lot of the manufacturing steps that would normally be required to produce a battery material.”

The project began as a collaboration between the Georgia Tech team and Atlanta-based aluminum manufacturer and recycler Novelis. The researchers are now working to scale up the size of the batteries to understand how size influences the behavior of aluminum.