Scientists at Sandia National Laboratories in the US have figured out how to use ordinary microwave technology to mine dead batteries. It sounds crazy, but it works. 

The team developed a microwave-based method to upcycle old lithium-ion battery cathodes. 

Interestingly, the microwave method slashes the time required to turn old lithium cobalt oxide powder into nanosheets from 7 days to just 2 hours.

Recycling cathodes

The development comes at an important time. Millions of early-generation electric vehicle batteries are reaching the end of their lifespans. Usually, the old vehicle parts head straight for the landfill. That is a massive waste of precious metals. 

Batteries use cathodes, which are packed with expensive, hard-to-find minerals like lithium and cobalt. Cobalt is especially problematic. The Democratic Republic of the Congo mines roughly 70 percent of the world’s supply, leaving global tech supply chains incredibly vulnerable to political disruption.

“Cobalt is a critical material for almost all consumer electronics,” said Clare Davis-Wheeler Chin, a Sandia nanomaterials chemist and an inventor of the method. 

“Since there’s only one main source of cobalt, it would be very easy for the cobalt supply chain to just disappear. We’re about to have an abundance of old EV batteries that are either going to go to the landfill or that we can mine to develop a domestic supply,” added Chin. 

Using an adjustable microwave reactor and a large positively charged chemical ion, researchers can break down old battery cathode powder.

Microwaves are known for uneven heating, a quirk that usually frustrates anyone trying to reheat leftovers. For battery chemists, however, that uneven hot-and-cold friction is a feature, not a bug. The localized heat spikes violently rip the stubborn lithium cobalt oxide cathode powder apart, unraveling it into microscopic layers called nanosheets.

The speed of the process is interesting. Standard methods of breaking down this material take a full week of high-temperature baking. The microwave method does it in just two hours.

It is also incredibly efficient. Previous laboratory attempts to create these nanosheets maxed out at a 60 percent yield, but Sandia’s microwave technique successfully converts 95 percent of the starting material.

“When you have nanosheets, ion exchange can access the entire sheet, and you can maximize the amount of critical materials that can be exchanged,” said Aliya Lapp, a Sandia electrochemist with expertise in galvanic ion exchange.

Economically beneficial

The flexibility of these ultra-thin nanosheets allows easy replacement of aged metal ions to keep pace with changing market trends. For example, substituting expensive cobalt with cheaper, higher-performing nickel to meet modern automotive standards. 

Interestingly, this method automatically heals microscopic defects and removes impurities accumulated over a decade of use. It eliminates the complex processing steps required by standard recycling. 

Furthermore, any extracted cobalt can be captured using a specialized molecular framework and reused, thereby allowing researchers to design two upgraded, industry-ready cathodes from the remains of a single dead battery.

Standard recycling centers operate like massive, energy-hogging blast furnaces. Sandia’s process keeps things cool, cheap, and fast. Preliminary economic modeling indicates the technique could boost battery recycling profits by a massive 30 percent compared to standard commercial methods. 

The tech is moving quickly out of the lab. The research team has already filed two patents and interviewed 80 industrial leaders to prep the technology for the commercial market.

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