A Reversible Self-Assembling Solid-State Battery Electrolyte From MIT

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How many times have you read it here at CleanTechnica? The EV revolution is still in its earliest stages. Right now, it is about where the automobile was when the engines still had to be cranked by hand or you needed to wait for it to build a head of steam. Improvements came thick and fast, as clever minds found solutions to thorny hardware issues. The same will happen with battery-operated cars.

There are plenty of folks who like to bash EVs because…well, for any reason they can find. Just about everyone in the flailing federal government loathes them because the don’t waste exajoules of precious fossil fuel energy. The nerve of some people! But behind the scenes, researchers are diligently seeking solutions that will improve the EV experience the way the self starter and automatic transmission did for conventional cars.

One of the common complaints we hear is that EV batteries are hard to recycle. We don’t care about the billions of discarded rubber tires in the world or quadrillions of discarded single use plastics, because, hey, that’s just business. But batteries? That’s a scourge that must be stopped!

There are companies doing amazing things when it comes to recycling EV batteries. Redwood Materials, founded by former Tesla CTO JB Straubel is one. It claims it can recover 90% or more of the raw materials inside batteries at a purity that meets or exceeds original expectations.

But the pace of progress continues unabated and traditional lithium-ion batteries are now being chased hard by solid-state batteries that offer greater safety, higher energy density, and faster charging in all temperatures. They aren’t quite here yet, but the news is filled with promising reports from giants like CATL and startups like Quantumscape.

On August 28. 2025, researchers at MIT published a study in the journal Nature Chemistry in which they reveal a new process that creates a self-assembling electrolyte for solid-state batteries that can be broken down and reused in a simple, non-toxic liquid bath. How is that possible? Don’t ask me. I failed chemistry in college, but the abstract of that study says,

Performance often overshadows recyclability in contemporary battery designs, leading to sustainability challenges. Preemptive strategies integrating recyclable chemistry from the outset are thus increasingly critical for addressing the complexities in conventional recycling. Here we harness bio-inspired molecular self-assembly to create inherently recyclable battery materials.

We use aramid amphiphiles that self-assemble in water through strong, collective hydrogen bonding and π–π stacking, forming air-stable, high-aspect-ratio nanoribbons with gigapascal-level stiffness. When processed into bulk solid-state electrolytes, these nanoribbons retain their ordered molecular arrangement and exhibit total conductivities of 1.6 × 10−4 S cm−1 at 50 °C, Young’s moduli of 70 MPa and toughness values of 1 MJ m−3, despite being stabilized solely by reversible non-covalent bonds.

We further demonstrate clean separation of battery components by exposing used cells to an organic solvent, which disrupts the non-covalent cohesion and reverts all battery components to their original forms. This study underscores the potential of molecular self-assembly for specialized recyclable designs in energy storage applications.

Unpacking The Jargon

There’s some jargon in there that may be hard for those of us who did not major in chemistry to grasp, but an MIT News blog post the same day helped break it down so even ordinary clods like me can understand it. That post claims the researchers have developed “a new kind of self-assembling battery material that quickly breaks apart when submerged in a simple organic liquid…The material can work as the electrolyte in a functioning, solid-state battery cell and then revert back to its original molecular components in minutes.”

Well, that is certainly very cool stuff. Instead of shredding a battery into a mixed, hard-to-recycle mass, when the new material returns to its original molecular form, the entire battery disassembles to accelerate the recycling process.

“So far in the battery industry, we’ve focused on high-performing materials and designs, and only later tried to figure out how to recycle batteries made with complex structures and hard-to-recycle materials,” says the paper’s first author Yukio Cho. “Our approach is to start with easily recyclable materials and figure out how to make them battery-compatible. Designing batteries for recyclability from the beginning is a new approach.”

We never know where inspiration will come from. Cho says he was struck by a scene in a Harry Potter movie in which Professor Dumbledore repairs a dilapidated home with a magic incantation and the flick of his wrist. Later he attended a talk about engineering molecules so they could assemble into complex structures and then revert back to their original form, and wondered whether such a thing could work to make batteries more recyclable.

To simplify the recycling process, the researchers decided to make a new electrolyte using a class of molecules that self-assemble in water. They are called aramid amphiphiles and their chemical structure and stability mimic that of Kevlar. The added a polyethylene glycol molecule to each AA molecule and found they spontaneously form nano-ribbons with ion-conducting PEG surfaces and bases that imitate the robustness of Kevlar through tight hydrogen bonding when exposed to water. The result is a mechanically stable nano-ribbon structure that conducts ions across its surface.

“The material is composed of two parts,” Cho explains. “The first part is this flexible chain that gives us a nest, or host, for lithium ions to jump around. The second part is this strong organic material component that is used in the Kevlar, which is a bulletproof material. Those make the whole structure stable. Within five minutes of being added to water, the solution becomes gel-like, indicating there are so many nanofibers formed in the liquid that they start to entangle each other. What’s exciting is we can make this material at scale because of the self-assembly behavior.”

When the team tested the material’s strength and toughness, they found it could endure the stresses associated with making and running the battery. They also constructed a solid-state battery cell that used lithium iron phosphate for the cathode and lithium titanium oxide as the anode, both common materials in today’s batteries.

When the researchers immersed the prototype battery cell in organic solvents, the material immediately dissolved, with each part of the battery falling away for easier recycling. Cho compared the materials’ reaction to cotton candy being submerged in water. “The electrolyte holds the two battery electrodes together and provides the lithium-ion pathways. So, when you want to recycle the battery, the entire electrolyte layer can fall off naturally and you can recycle the electrodes separately.”

The Self-Assembling Battery Is Still A Dream

The nano-ribbons moved lithium ions successfully between the electrodes, but a side-effect known as polarization limited the movement of lithium ions into the battery’s electrodes during fast bouts of charging and discharging, hampering its performance compared to today’s best commercially available batteries. “The lithium ions moved along the nano-fiber all right, but getting the lithium ion from the nano-fibers to the metal oxide seems to be the most sluggish point of the process,” Cho said.

But he is not worried. He says the material is a proof of concept that demonstrates the recycle-first approach. “We don’t want to say we solved all the problems with this material. Our battery performance was not fantastic because we used only this material as the entire electrolyte for the paper, but what we’re picturing is using this material as one layer in the battery electrolyte. It doesn’t have to be the entire electrolyte to kick off the recycling process.”

The experiments in the lab will now shift to exploring ways to integrate these kinds of materials into existing battery designs as well as implementing the ideas into new battery chemistries. “It’s very challenging to convince existing vendors to do something very differently,” Cho says. “But with new battery materials that may come out in five or 10 years, it could be easier to integrate this into new designs in the beginning.”

Cho thinks this new approach could also help reshore lithium supplies by reusing materials from batteries that are already in the US. “People are starting to realize how important this is,” Cho says. “If we can start to recycle lithium-ion batteries from battery waste at scale, it’ll have the same effect as opening lithium mines in the US. Also, each battery requires a certain amount of lithium, so extrapolating out the growth of electric vehicles, we need to reuse this material to avoid massive lithium price spikes.”

The Future Of Battery Recycling

So what we have here is a glimmer of sunshine that points toward a future in which battery recycling is easier and less expensive — all of which should encourage the transition to electric transportation. That’s a very hopeful sign. But there is a cloud on the horizon. The research by Cho and his team was supported by the National Science Foundation and the US Department of Energy.

With fossil fuel extremist Chris “Gonzo” Wright now heading up the Energy Department, is there any guarantee that funding will continue? That seems unlikely, meaning this and similar critical research could be set back years by a government that relies on ideology more than science.