How to Efficiently Recycle Li-ion Batteries

A research team at Rice University is tackling the environmental issue of efficiently recycling Li-ion batteries amid their increasing use.

A research team at Rice University led by James Tour, the T.T. and W.F. Chao Professor of Chemistry and Professor of Materials Science and Nanoengineering, is tackling the environmental issue of efficiently recycling Li-ion batteries amid their increasing use.

The team has pioneered a new method to extract purified active materials from battery waste as detailed recently in the journal Nature Communications. Their findings have the potential to facilitate the effective separation and recycling of valuable battery materials at a minimal fee, contributing to a greener production of electric vehicles (EVs).

“With the surge in battery use, particularly in EVs, the need for developing sustainable recycling methods is pressing,” Tour said.

Conventional recycling techniques typically involve breaking down battery materials into their elemental forms through energy-intensive thermal or chemical processes that are costly and have significant environmental impacts.

The team proposed that magnetic properties could facilitate the separation and purification of spent battery materials.

Their innovation uses a method known as solvent-free flash Joule heating (FJH). This technique devised by Tour involves passing a current through a moderately resistive material to rapidly heat and transform it into other substances.

Using FJH, the researchers heated battery waste to 2,500 Kelvin within seconds, creating unique features with magnetic shells and stable core structures. The magnetic separation allowed for efficient purification.

During the process, the cobalt-based battery cathodes — typically used in EVs and associated with high financial, environmental, and social costs — unexpectedly showed magnetism in the outer spinel cobalt oxide layers, allowing for easy separation.

The researchers’ approach resulted in a high battery metal recovery yield of 98 percent with the value of battery structure maintained.

“Notably, the metal impurities were significantly reduced after separation while preserving the structure and functionality of the materials,” Tour said. “The bulk structure of battery materials remains stable and is ready to be reconstituted into new cathodes.”

The full article including an exclusive interview with co-author Weiyin Chen can be found at: How to Efficiently Recycle Li-ion Batteries - Tech Briefs