Breakthrough in EV Battery Recycling and Solid-State Technology

Researchers are addressing critical obstacles in battery technology by concentrating on both the start and the end of a battery’s lifespan.

A team at Worcester Polytechnic Institute (WPI) in Massachusetts has enhanced battery performance and introduced an eco-friendly recycling approach.

Under the direction of Professor Yan Wang, the researchers concentrated on advancing solid-state batteries. These batteries are viewed as a safer, more stable alternative to traditional lithium-ion batteries.

Iron-doped material

The newly engineered iron-doped compound streamlines the architecture of next-generation solid-state batteries.

It tackles a significant problem with solid-state batteries: the mismatch between halide-based solid electrolytes and lithium-metal anodes.

That problem is typically addressed by adding protective interlayers, but those layers raise both the expense and the complexity of the batteries.

The team resolved this by doping lithium-indium chloride with iron.

This alteration produced a material that can form direct, stable contact with lithium-indium anodes, removing the necessity for an expensive and complicated protective interlayer.

Notably, the novel material preserved excellent ionic conductivity and exhibited remarkable long-term stability.

Complete battery cells employing this material managed over 300 charge-discharge cycles while still maintaining 80 percent of their original capacity. This is an important indicator of a battery’s durability.

Additionally, symmetric cells, which are used to evaluate the electrolyte’s own stability, ran for more than 500 hours with no signs of degradation.

The team states these outcomes are the “first such demonstration in the field” to illustrate this degree of long-term stability.

“This work establishes iron doping as an effective strategy to simplify solid-state battery design while enhancing stability and performance,” said Wang.

Recycling lithium anodes

The researchers also developed a safe, scalable technique for recycling highly reactive lithium-metal anodes.

By using a “self-driven” aldol condensation reaction with acetone, the team converted spent lithium anodes into valuable lithium carbonate (Li2CO3).

Importantly, the recovered material was extremely pure, achieving 99.79 percent purity, which surpasses specifications for materials used in new batteries.

The researchers demonstrated the practical viability of their recycling approach by using the reclaimed lithium carbonate to synthesize new cathode materials.

Those new cathodes were then evaluated and found to have electrochemical performance on par with commercial products.

The tests showed that the recycled material is high quality and can be fed back into the battery manufacturing cycle.

The advance offers a workable way to cut dependence on freshly mined lithium, which helps reduce production costs and accelerate the uptake of cleaner energy technologies.

“This method is an effective solution to one of the most pressing challenges in the battery industry,” said Wang.

“By turning a safety liability into a driving force for recovery, we’ve created a process that is both practical for industry adoption and critical for building a more sustainable energy future,” the author added.

It could lead to creating more powerful, safer, and sustainable lithium batteries for the future of electric vehicles and renewable energy storage.

The findings have been reported in two journals: Joule and Materials Today.